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Ranieri V, Gordon C, Kamboj SK, Edwards SJ. Pandemic lockdowns: who feels coerced and why? - a study on perceived coercion, perceived pressures and procedural justice during the UK COVID-19 lockdowns. BMC Public Health 2024; 24:793. [PMID: 38481190 PMCID: PMC10938678 DOI: 10.1186/s12889-024-17985-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 02/04/2024] [Indexed: 03/17/2024] Open
Abstract
BACKGROUND This study examined perceptions of coercion, pressures and procedural injustice and how such perceptions influenced psychological well-being in those who experienced a UK COVID-19 lockdown, with a view to preparing for the possibility of future lockdowns. METHODS 40 individuals categorised as perceiving the lockdown(s) as either highly or lowly coercive took part in one of six asynchronous virtual focus groups (AVFGs). RESULTS Using thematic analysis, the following key themes were identified in participants' discussions: (1) Choice, control and freedom; (2) threats; (3) fairness; (4) circumstantial factors; and (5) psychological factors. CONCLUSIONS As the first qualitative study to investigate the psychological construct of perceived coercion in relation to COVID-19 lockdowns, its findings suggest that the extent to which individuals perceived pandemic-related lockdowns as coercive may have been linked to their acceptance of restrictions. Preparing for future pandemics should include consideration of perceptions of coercion and efforts to combat this, particularly in relation to differences in equity, in addition to clarity of public health messaging and public engagement.
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Affiliation(s)
- V Ranieri
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK.
- Department of Science, Technology, Engineering and Public Policy (STEaPP), University College London, London, UK.
| | - C Gordon
- Department of Science, Technology, Engineering and Public Policy (STEaPP), University College London, London, UK
| | - S K Kamboj
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - S J Edwards
- Department of Science, Technology, Engineering and Public Policy (STEaPP), University College London, London, UK.
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McAlpine RG, Sacchet MD, Simonsson O, Khan M, Krajnovic K, Morometescu L, Kamboj SK. Development of a digital intervention for psychedelic preparation (DIPP). Sci Rep 2024; 14:4072. [PMID: 38374177 PMCID: PMC10876638 DOI: 10.1038/s41598-024-54642-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 02/14/2024] [Indexed: 02/21/2024] Open
Abstract
Psychedelic substances induce profound alterations in consciousness. Careful preparation is therefore essential to limit adverse reactions, enhance therapeutic benefits, and maintain user safety. This paper describes the development of a self-directed, digital intervention for psychedelic preparation. Drawing on elements from the UK Medical Research Council (MRC) framework for developing complex interventions, the design was informed by a four-factor model of psychedelic preparedness, using a person-centred approach. Our mixed-methods investigation consisted of two studies. The first involved interviews with 19 participants who had previously attended a 'high-dose' psilocybin retreat, systematically exploring their preparation behaviours and perspectives on the proposed intervention. The second study engaged 28 attendees of an ongoing psilocybin retreat in co-design workshops, refining the intervention protocol using insights from the initial interviews. The outcome is a co-produced 21-day digital course (Digital Intervention for Psychedelic Preparation (DIPP)), that is organised into four modules: Knowledge-Expectation, Psychophysical-Readiness, Safety-Planning, and Intention-Preparation. Fundamental components of the course include daily meditation practice, supplementary exercises tied to the weekly modules, and mood tracking. DIPP provides a comprehensive and scalable solution to enhance psychedelic preparedness, aligning with the broader shift towards digital mental health interventions.
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Affiliation(s)
- Rosalind G McAlpine
- Clinical Psychopharmacology Unit, Clinical, Educational and Health Psychology, University College London, London, UK.
| | - Matthew D Sacchet
- Meditation Research Program, Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, USA
| | - Otto Simonsson
- Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Solna, Sweden
| | - Maisha Khan
- Clinical Psychopharmacology Unit, Clinical, Educational and Health Psychology, University College London, London, UK
| | - Katarina Krajnovic
- Clinical Psychopharmacology Unit, Clinical, Educational and Health Psychology, University College London, London, UK
| | - Larisa Morometescu
- Clinical Psychopharmacology Unit, Clinical, Educational and Health Psychology, University College London, London, UK
| | - Sunjeev K Kamboj
- Clinical Psychopharmacology Unit, Clinical, Educational and Health Psychology, University College London, London, UK
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McAlpine RG, Blackburne G, Kamboj SK. Development and psychometric validation of a novel scale for measuring 'psychedelic preparedness'. Sci Rep 2024; 14:3280. [PMID: 38332334 PMCID: PMC10853197 DOI: 10.1038/s41598-024-53829-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 02/05/2024] [Indexed: 02/10/2024] Open
Abstract
Preparing participants for psychedelic experiences is crucial for ensuring these experiences are safe and, potentially beneficial. However, there is currently no validated measure to assess the extent to which participants are well-prepared for such experiences. Our study aimed to address this gap by developing, validating, and testing the Psychedelic Preparedness Scale (PPS). Using a novel iterative Delphi-focus group methodology ('DelFo'), followed by qualitative pre-test interviews, we incorporated the perspectives of expert clinicians/researchers and of psychedelic users to generate items for the scale. Psychometric validation of the PPS was carried out in two large online samples of psychedelic users (N = 516; N = 716), and the scale was also administered to a group of participants before and after a 5-7-day psilocybin retreat (N = 46). Exploratory and confirmatory factor analysis identified four factors from the 20-item PPS: Knowledge-Expectations, Intention-Preparation, Psychophysical-Readiness, and Support-Planning. The PPS demonstrated excellent reliability (ω = 0.954) and evidence supporting convergent, divergent and discriminant validity was also obtained. Significant differences between those scoring high and low (on psychedelic preparedness) before the psychedelic experience were found on measures of mental health/wellbeing outcomes assessed after the experience, suggesting that the scale has predictive utility. By prospectively measuring modifiable pre-treatment preparatory behaviours and attitudes using the PPS, it may be possible to determine whether a participant has generated the appropriate mental 'set' and is therefore likely to benefit from a psychedelic experience, or at least, less likely to be harmed.
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Affiliation(s)
- Rosalind G McAlpine
- Clinical Psychopharmacology Unit, Clinical, Educational and Health Psychology, University College London, London, UK.
| | - George Blackburne
- Clinical Psychopharmacology Unit, Clinical, Educational and Health Psychology, University College London, London, UK
- Experimental Psychology, University College London, London, UK
| | - Sunjeev K Kamboj
- Clinical Psychopharmacology Unit, Clinical, Educational and Health Psychology, University College London, London, UK
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Raihani NJ, Kamboj SK, Peniket MJ, Norman J, Ozturk OC, Iskandar G, Bell V. The effects of paranoia and dopamine on perception of cohesion and conspiracy: a pre-registered, double-blind, placebo-controlled experiment. Psychopharmacology (Berl) 2024; 241:195-205. [PMID: 37848635 PMCID: PMC10774203 DOI: 10.1007/s00213-023-06476-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 10/02/2023] [Indexed: 10/19/2023]
Abstract
Paranoia is a common symptom of psychotic disorders but is also present on a spectrum of severity in the general population. Although paranoia is associated with an increased tendency to perceive cohesion and conspiracy within groups, the mechanistic basis of this variation remains unclear. One potential avenue involves the brain's dopaminergic system, which is known to be altered in psychosis. In this study, we used large-N online samples to establish the association between trait paranoia and perceptions of cohesion and conspiracy. We further evaluated the role of dopamine on perceptions of cohesion and conspiracy using a double-blind, placebo-controlled laboratory experiment where participants received levodopa or a placebo control. Our results were mixed: group perceptions and perceptions of cohesion were higher among more paranoid individuals but were not altered under dopamine administration. We outline the potential reasons for these discrepancies and the broader implications for understanding paranoia in terms of dopamine dysregulation.
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Affiliation(s)
- N J Raihani
- Department of Experimental Psychology, University College London, 26 Bedford Way, London, WC1H 0AP, UK.
- School of Psychology, University of Auckland, Auckland, New Zealand.
| | - S K Kamboj
- Clinical Psychopharmacology Unit, Department of Clinical, Educational & Health Psychology, University College London, 1-19 Torrington Place, WC1E 7HB, London, UK
| | - M J Peniket
- Clinical Psychopharmacology Unit, Department of Clinical, Educational & Health Psychology, University College London, 1-19 Torrington Place, WC1E 7HB, London, UK
| | - J Norman
- Department of Clinical, Educational & Health Psychology, University College London, 1-19 Torrington Place, WC1E 7HB, London, UK
| | - O C Ozturk
- Department of Experimental Psychology, University College London, 26 Bedford Way, London, WC1H 0AP, UK
| | - G Iskandar
- Department of Anaesthesia and Perioperative Medicine, UCLH, London, UK
| | - V Bell
- Department of Clinical, Educational & Health Psychology, University College London, 1-19 Torrington Place, WC1E 7HB, London, UK
- South London & Maudsley NHS Foundation Trust, London, UK
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Lorenzetti V, Gaillard A, Beyer E, Kowalczyk M, Kamboj SK, Manning V, Gleeson J. Do mindfulness-based interventions change brain function in people with substance dependence? A systematic review of the fMRI evidence. BMC Psychiatry 2023; 23:407. [PMID: 37286936 DOI: 10.1186/s12888-023-04789-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 04/14/2023] [Indexed: 06/09/2023] Open
Abstract
BACKGROUND Substance use disorders (SUDs) affect ~ 35 million people globally and are associated with strong cravings, stress, and brain alterations. Mindfulness-based interventions (MBIs) can mitigate the adverse psychosocial outcomes of SUDs, but the underlying neurobiology is unclear. Emerging findings were systematically synthesised from fMRI studies about MBI-associated changes in brain function in SUDs and their associations with mindfulness, drug quantity, and craving. METHODS PsycINFO, Medline, CINAHL, PubMed, Scopus, and Web of Science were searched. Seven studies met inclusion criteria. RESULTS Group by time effects indicated that MBIs in SUDs (6 tobacco and 1 opioid) were associated with changes in the function of brain pathways implicated in mindfulness and addiction (e.g., anterior cingulate cortex and striatum), which correlated with greater mindfulness, lower craving and drug quantity. CONCLUSIONS The evidence for fMRI-related changes with MBI in SUD is currently limited. More fMRI studies are required to identify how MBIs mitigate and facilitate recovery from aberrant brain functioning in SUDs.
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Affiliation(s)
- Valentina Lorenzetti
- Neuroscience of Addiction and Mental Health Program, Healthy Brain and Mind Research Centre, School of Behavioural and Health Sciences, Faculty of Health Sciences, Australian Catholic University, Level 5 Daniel Mannix Building, 115 Victoria Parade, Fitzroy, VIC, 3065, Australia.
| | - Alexandra Gaillard
- Neuroscience of Addiction and Mental Health Program, Healthy Brain and Mind Research Centre, School of Behavioural and Health Sciences, Faculty of Health Sciences, Australian Catholic University, Level 5 Daniel Mannix Building, 115 Victoria Parade, Fitzroy, VIC, 3065, Australia
- Centre for Mental Health, Swinburne University of Technology, Hawthorn, Australia
| | - Emillie Beyer
- Neuroscience of Addiction and Mental Health Program, Healthy Brain and Mind Research Centre, School of Behavioural and Health Sciences, Faculty of Health Sciences, Australian Catholic University, Level 5 Daniel Mannix Building, 115 Victoria Parade, Fitzroy, VIC, 3065, Australia
| | - Magdalena Kowalczyk
- Neuroscience of Addiction and Mental Health Program, Healthy Brain and Mind Research Centre, School of Behavioural and Health Sciences, Faculty of Health Sciences, Australian Catholic University, Level 5 Daniel Mannix Building, 115 Victoria Parade, Fitzroy, VIC, 3065, Australia
| | - Sunjeev K Kamboj
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Victoria Manning
- Monash Addiction Research Centre, Eastern Health Clinical School, Monash University, Melbourne, Australia
- Turning Point, Eastern Health, Monash University, Melbourne, Australia
| | - John Gleeson
- Digital Innovations in Mental Health and Well-being Program, Healthy Brain and Mind Research Centre, School of Behavioural and Health Sciences, Australian Catholic University, Melbourne, VIC, Australia
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Ranieri V, Kamboj SK, Edwards SJL. Perceived coercion, perceived pressures and procedural justice arising from global lockdowns during the COVID-19 pandemic: A scoping review. PLOS Glob Public Health 2023; 3:e0001250. [PMID: 36962987 PMCID: PMC10019622 DOI: 10.1371/journal.pgph.0001250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 02/08/2023] [Indexed: 03/18/2023]
Abstract
This aim of this scoping review is to map what is known about perceived coercion, perceived pressures and procedural justice within the context of the general population's experience of 'lockdowns' imposed by governments worldwide in response to the increased transmission of COVID-19. Arksey & O'Malley's (2005) framework for conducting scoping reviews was chosen. A sensitive search strategy was devised and conducted using PubMed, Scopus, and Web of Science using the following search terms: (adherence OR acceptance OR agreement OR trust OR distrust OR compliance OR willing*) OR (perceived coerc* OR percept* coerc* OR pressure OR force OR influence OR control OR threat OR justice) AND (lockdown) AND (COVID OR SARS-CoV-2 OR COVID-19). The database search initially produced 41,628 articles to screen. A total of 40 articles were included in this review and the following five themes were identified from the studies: perceived acceptability and willingness to adhere to lockdown; perceived control during lockdown; perceived pressures arising from lockdown; perceived threat of sanction from others and the procedural (in)justice of lockdown. Our synthesis suggests that i) individuals experienced an initial willingness and tolerance of lockdown that lessened over time as perceptions of personal control decreased; ii) that social influences may pressure individuals to follow or break lockdown rules; and iii) that justifiability and proportionality together with individuals' perceptions of harm from COVID-19 may impact the extent to which individuals adhere to lockdown. Furthermore, the review found an absence of information regarding specific individual characteristics and circumstances that increase the likelihood of experiencing perceived coercion and its related constructs and highlights a need for a better understanding of the cultural and socioeconomic factors affecting perceptions of, and adherence to, lockdown.
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Affiliation(s)
- Veronica Ranieri
- Research Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
- Department of Science, Technology, Engineering and Public Policy (STEaPP), University College London, London, United Kingdom
- * E-mail:
| | - Sunjeev K. Kamboj
- Research Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
| | - Sarah J. L. Edwards
- Department of Science, Technology, Engineering and Public Policy (STEaPP), University College London, London, United Kingdom
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Kamboj SK, Peniket M, Simeonov L. A bioelectronic route to compassion: Rationale and study protocol for combining transcutaneous vagus nerve stimulation (tVNS) with compassionate mental imagery. PLoS One 2023; 18:e0282861. [PMID: 36913378 PMCID: PMC10010509 DOI: 10.1371/journal.pone.0282861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 02/19/2023] [Indexed: 03/14/2023] Open
Abstract
BACKGROUND The vagus nerve (VN) is a neural nexus between the brain and body, enabling bidirectional regulation of mental functioning and peripheral physiology. Some limited correlational findings suggest an association between VN activation and a particular form of self-regulation: compassionate responding. Interventions that are geared towards strengthening self-compassion in particular, can serve as an antidote to toxic shame and self-criticism and improve psychological health. OBJECTIVE We describe a protocol for examining the role of VN activation on 'state' self-compassion, self-criticism, and related outcomes. By combining transcutaneous vagus nerve stimulation (tVNS) with a brief imagery-based self-compassion intervention, we aim to preliminarily test additivity versus synergy between these distinct bottom-up and top-down methods for putatively regulating vagal activity. We also test whether the effects of VN stimulation accumulate with daily stimulation and daily compassionate imagery practice. METHODS Using a randomized 2 x 2 factorial (stimulation x imagery condition) design, healthy volunteers (n = 120) receive active (tragus) or sham (earlobe) tVNS plus standardized (audio-recorded) self-compassionate or sham mental imagery instructions. These interventions are delivered in a university-based psychological laboratory in two sessions, one week apart, as well as being self-administered between sessions by participants at home. Pre-stimulation, peri-stimulation and post-imagery measures of state self-compassion, self-criticism and related self-report outcomes are assessed in two lab sessions, separated by a week (Days 1 and 8). Heart rate variability is used as a physiological metric of vagal activity and an eye-tracking task assesses attentional bias to compassionate faces during the two lab sessions. On Days 2-7, participants continue their randomly assigned stimulation and imagery tasks at home, and complete state measures at the end of each remote session. DISCUSSION Demonstrating modulation of compassionate responding using tVNS would support a causal link between VN activation and compassion. This would provide a basis for future studies of bioelectronic approaches to augmenting therapeutic contemplative techniques. CLINICAL TRIALS REGISTRATION ClinicalTrials.gov, Identifier: NCT05441774 (Date: July 1st 2022). OSF REGISTRATION https://osf.io/4t9ha.
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Affiliation(s)
- Sunjeev K. Kamboj
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
- * E-mail:
| | - Matthew Peniket
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
| | - Louise Simeonov
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
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Azmoodeh K, Thomas E, Kamboj SK. Meditation trips: A thematic analysis of the combined naturalistic use of psychedelics with meditation practices. Exp Clin Psychopharmacol 2022; 31:756-767. [PMID: 36534415 DOI: 10.1037/pha0000617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Similarities between meditative and psychedelic states have long been recognized. Recently, parallels in the psychological mechanisms mediating the beneficial effects of mindfulness and psychedelic treatments-as well as their potential therapeutic complementarity-have been noted. However, empirical research in this area remains limited. Here, we explore the naturalistic use of meditation practices among psychedelic users recruited outside of treatment/retreat or research settings. Participants with ≥ 1 psychedelic drug experience(s) were included in an online survey. The majority (n = 875; 66.5%) indicated that they engaged in meditation, 39.4% (n = 345) of whom had combined psychedelic use with meditation practices on ≥ 1 occasion. The majority (74.2%; n = 256) provided written accounts describing their experiences of "psychedelic-meditation," which were the basis for the present thematic analytic study. Six overarching themes were identified: (1) Compatibility Between Psychedelic and Meditative States; (2) Enhancement of the Meditative and Psychedelic Experience; (3) Beneficial Changes in Relating to the Internal and External World (encompassing acceptance, connection, peacefulness, and transformation); (4) Negative Effects of Combined Use; (5) Meditation as a Preparatory and Navigational Tool; and (6) Contextual Considerations (including reflections upon, and practical advice about, combining meditation and psychedelics). Participants' experiences appear to support recent empirical and theoretical work on the parallels and complementarity between psychedelic drug effects and meditation. The findings identify facilitating conditions for combining psychedelics with meditation, which may have implications for their combined therapeutic use. For example, the use of meditation techniques might represent a "psychedelic-sparing" strategy, potentially enabling therapeutically important psychedelic effects to emerge at lower doses. (PsycInfo Database Record (c) 2022 APA, all rights reserved).
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Affiliation(s)
- Kiana Azmoodeh
- Research Department Clinical, Educational and Health Psychology
| | - Emily Thomas
- Research Department Clinical, Educational and Health Psychology
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Cawley E, Piazza G, Das RK, Kamboj SK. A systematic review of the pharmacological modulation of autobiographical memory specificity. Front Psychol 2022; 13:1045217. [PMID: 36452391 PMCID: PMC9703074 DOI: 10.3389/fpsyg.2022.1045217] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 10/27/2022] [Indexed: 08/31/2023] Open
Abstract
Background Over-general autobiographical memory (AM) retrieval is proposed to have a causal role in the maintenance of psychological disorders like depression and PTSD. As such, the identification of drugs that modulate AM specificity may open up new avenues of research on pharmacological modeling and treatment of psychological disorders. Aim The current review summarizes randomized, placebo-controlled studies of acute pharmacological modulation of AM specificity. Method A systematic search was conducted of studies that examined the acute effects of pharmacological interventions on AM specificity in human volunteers (healthy and clinical participants) measured using the Autobiographical Memory Test. Results Seventeen studies were identified (986 total participants), of which 16 were judged to have low risk of bias. The presence and direction of effects varied across drugs and diagnostic status of participants (clinical vs. healthy volunteers). The most commonly studied drug-hydrocortisone-produced an overall impairment in AM specificity in healthy volunteers [g = -0.28, CI (-0.53, -0.03), p = 0.03], although improvements were reported in two studies of clinical participants. In general, studies of monoamine modulators reported no effect on specificity. Conclusion Pharmacological enhancement of AM specificity is inconsistent, although monaminergic modulators show little promise in this regard. Drugs that reduce AM specificity in healthy volunteers may be useful experimental-pharmacological tools that mimic an important transdiagnostic impairment in psychological disorders. Systematic review registration PROSPERO, identifier CRD42020199076, https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020199076.
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Affiliation(s)
- Emma Cawley
- Research Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
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Piazza GG, Iskandar G, Hennessy V, Zhao H, Walsh K, McDonnell J, Terhune DB, Das RK, Kamboj SK. Pharmacological modelling of dissociation and psychosis: an evaluation of the Clinician Administered Dissociative States Scale and Psychotomimetic States Inventory during nitrous oxide ('laughing gas')-induced anomalous states. Psychopharmacology (Berl) 2022; 239:2317-2329. [PMID: 35348804 PMCID: PMC9205822 DOI: 10.1007/s00213-022-06121-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 03/15/2022] [Indexed: 12/13/2022]
Abstract
RATIONALE A significant obstacle to an improved understanding of pathological dissociative and psychosis-like states is the lack of readily implemented pharmacological models of these experiences. Ketamine has dissociative and psychotomimetic effects but can be difficult to use outside of medical and clinical-research facilities. Alternatively, nitrous oxide (N2O) - like ketamine, a dissociative anaesthetic and NMDAR antagonist - has numerous properties that make it an attractive alternative for modelling dissociation and psychosis. However, development and testing of such pharmacological models relies on well-characterized measurement instruments. OBJECTIVES To examine the factor structures of the Clinician Administered Dissociative States Scale (CADSS) and Psychotomimetic States Inventory (PSI) administered during N2O inhalation in healthy volunteers. METHODS Secondary analyses of data pooled from three previous N2O studies with healthy volunteers. RESULTS Effect sizes for N2O-induced dissociation and psychotomimesis were comparable to effects reported in experimental studies with sub-anaesthetic ketamine in healthy volunteers. Although, like ketamine, a three-factor representation of N2O-induced dissociation was confirmed, and a more parsimonious two-factor model might be more appropriate. Bayesian exploratory factor analysis suggested that N2O-induced psychosis-like symptoms were adequately represented by two negative and two positive symptom factors. Hierarchical cluster analysis indicated minimal item overlap between the CADSS and PSI. CONCLUSION N2O and ketamine produce psychometrically similar dissociative states, although parallels in their psychosis-like effects remain to be determined. The CADSS and PSI tap largely non-overlapping experiences under N2O and we propose the use of both measures (or similar instruments) to comprehensively assess anomalous subjective states produced by dissociative NMDAR antagonists.
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Affiliation(s)
- Giulia G. Piazza
- grid.83440.3b0000000121901201Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Georges Iskandar
- grid.83440.3b0000000121901201Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, UK ,grid.439749.40000 0004 0612 2754Department of Anaesthesia and Perioperative Medicine, University College London Hospital, London, UK
| | - Vanessa Hennessy
- grid.83440.3b0000000121901201Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Hannah Zhao
- grid.83440.3b0000000121901201Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Katie Walsh
- grid.83440.3b0000000121901201Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Jeffrey McDonnell
- grid.83440.3b0000000121901201Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Devin B. Terhune
- grid.4464.20000 0001 2161 2573Department of Psychology, Goldsmiths, University of London, London, UK
| | - Ravi K. Das
- grid.83440.3b0000000121901201Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Sunjeev K. Kamboj
- grid.83440.3b0000000121901201Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
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Gale G, Walsh K, Hennessy VE, Stemerding LE, Ni KS, Thomas E, Kamboj SK, Das RK. Long-term behavioural rewriting of maladaptive drinking memories via reconsolidation-update mechanisms. Psychol Med 2021; 51:2875-2885. [PMID: 32539883 DOI: 10.1017/s0033291720001531] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Alcohol use disorders can be conceptualised as a learned pattern of maladaptive alcohol-consumption behaviours. The memories encoding these behaviours centrally contribute to long-term excessive alcohol consumption and are therefore an important therapeutic target. The transient period of memory instability sparked during memory reconsolidation offers a therapeutic window to directly rewrite these memories using targeted behavioural interventions. However, clinically-relevant demonstrations of the efficacy of this approach are few. We examined key retrieval parameters for destabilising naturalistic drinking memories and the ability of subsequent counterconditioning to effect long-term reductions in drinking. METHODS Hazardous/harmful beer-drinking volunteers (N = 120) were factorially randomised to retrieve (RET) or not retrieve (No RET) alcohol reward memories with (PE) or without (No PE) alcohol reward prediction error. All participants subsequently underwent disgust-based counterconditioning of drinking cues. Acute responses to alcohol were assessed pre- and post-manipulation and drinking levels were assessed up to 9 months. RESULTS Greater long-term reductions in drinking were found when counterconditioning was conducted following retrieval (with and without PE), despite a lack of short-term group differences in motivational responding to acute alcohol. Large variability in acute levels of learning during counterconditioning was noted. 'Responsiveness' to counterconditioning predicted subsequent responses to acute alcohol in RET + PE only, consistent with reconsolidation-update mechanisms. CONCLUSIONS The longevity of behavioural interventions designed to reduce problematic drinking levels may be enhanced by leveraging reconsolidation-update mechanisms to rewrite maladaptive memory. However, inter-individual variability in levels of corrective learning is likely to determine the efficacy of reconsolidation-updating interventions and should be considered when designing and assessing interventions.
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Affiliation(s)
- Grace Gale
- Clinical, Educational and Health Psychology, UCL, 26 Bedford Way, LondonWC1H 0AP, UK
| | - Katie Walsh
- Clinical, Educational and Health Psychology, UCL, 26 Bedford Way, LondonWC1H 0AP, UK
| | - Vanessa E Hennessy
- Clinical, Educational and Health Psychology, UCL, 26 Bedford Way, LondonWC1H 0AP, UK
| | - L E Stemerding
- Clinical, Educational and Health Psychology, UCL, 26 Bedford Way, LondonWC1H 0AP, UK
| | - Koa Sher Ni
- Clinical, Educational and Health Psychology, UCL, 26 Bedford Way, LondonWC1H 0AP, UK
| | - Emily Thomas
- Clinical, Educational and Health Psychology, UCL, 26 Bedford Way, LondonWC1H 0AP, UK
| | - Sunjeev K Kamboj
- Clinical, Educational and Health Psychology, UCL, 26 Bedford Way, LondonWC1H 0AP, UK
| | - Ravi K Das
- Clinical, Educational and Health Psychology, UCL, 26 Bedford Way, LondonWC1H 0AP, UK
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12
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Thomas EM, Freeman TP, Poplutz P, Howden K, Hindocha C, Bloomfield M, Kamboj SK. Stimulating meditation: a pre-registered randomised controlled experiment combining a single dose of the cognitive enhancer, modafinil, with brief mindfulness training. J Psychopharmacol 2021; 35:621-630. [PMID: 33645313 PMCID: PMC8278547 DOI: 10.1177/0269881121991835] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Mindfulness-meditation has a variety of benefits on well-being. However, individuals with primary attentional impairments (e.g. attention deficit disorder) or attentional symptoms secondary to anxiety, depression or addiction, may be less likely to benefit, and require additional mindfulness-augmenting strategies. AIMS To determine whether a single dose of the cognitive enhancer, modafinil, acutely increases subjective and behavioural indices of mindfulness, and augments brief mindfulness training. METHODS A randomised, double-blind, placebo-controlled, 2 (drug: placebo, modafinil) × 2 (strategy: mindfulness, relaxation control) experiment was conducted. Seventy-nine meditation-naïve participants were assigned to: placebo-relaxation, placebo-mindfulness, modafinil-relaxation or modafinil-mindfulness. Pre-drug, post-drug and post-strategy state mindfulness, affect and autonomic activity, along with post-strategy sustained attention and mind-wandering were assessed within a single lab session. After the session, participants were instructed to practice their assigned behavioural strategy daily for one week, with no further drug administration, after which, follow-up measures were taken. RESULTS As predicted, modafinil acutely increased state mindfulness and improved sustained attention. Differential acute strategy effects were found following mindfulness on autonomic activity but not state mindfulness. There were no strategy or drug effects on mind-wandering. However, exploratory analyses indicated that participants receiving modafinil engaged in more strategy practice across strategy conditions during follow-up. CONCLUSIONS Modafinil acutely mimicked the effects of brief mindfulness training on state mindfulness but did not enhance the effects of this training. Limitations of the current study, and recommendations for future research examining modafinil as an adjunct to mindfulness- (or relaxation-) based treatments are discussed.
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Affiliation(s)
- Emily M Thomas
- Clinical Psychopharmacology Unit, University College London, London, UK
| | - Tom P Freeman
- Clinical Psychopharmacology Unit, University College London, London, UK,Addiction and Mental Health Group (AIM), University of Bath, Bath, UK
| | - Patrick Poplutz
- Clinical Psychopharmacology Unit, University College London, London, UK
| | - Kane Howden
- Clinical Psychopharmacology Unit, University College London, London, UK
| | - Chandni Hindocha
- Clinical Psychopharmacology Unit, University College London, London, UK,Translational Psychiatry Research Group, University College London, London, UK
| | - Michael Bloomfield
- Clinical Psychopharmacology Unit, University College London, London, UK,Translational Psychiatry Research Group, University College London, London, UK
| | - Sunjeev K Kamboj
- Clinical Psychopharmacology Unit, University College London, London, UK,Sunjeev K Kamboj, Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, Gower St, London, WC1E 6BT, UK.
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13
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Kamboj SK, Zhao H, Troebinger L, Piazza G, Cawley E, Hennessy V, Iskandar G, Das RK. Rewarding Subjective Effects of the NMDAR Antagonist Nitrous Oxide (Laughing Gas) Are Moderated by Impulsivity and Depressive Symptoms in Healthy Volunteers. Int J Neuropsychopharmacol 2021; 24:551-561. [PMID: 33667308 PMCID: PMC8299821 DOI: 10.1093/ijnp/pyab009] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 02/02/2021] [Accepted: 02/23/2021] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Nitrous oxide (N2O) is an anesthetic gas with both therapeutic and abuse potential. Because N2O is an NMDA receptor (NMDAR) antagonist, its effects are expected to resemble those of the prototypical NMDAR antagonist, ketamine. In this study, we examined the subjective rewarding effects of N2O using measures previously employed in studies of ketamine. We also tested for moderation of these effects by bipolar phenotype, depressive symptoms, and impulsivity. METHODS Healthy volunteers were randomly assigned to either 50% N2O (n = 40) or medical air (n = 40). Self-reported rewarding (liking and wanting), and alcohol-like effects were assessed pre-, peri- and post inhalation. RESULTS Effect sizes for the various rewarding/alcohol-like effects of N2O were generally similar to those reported in studies of moderate-dose ketamine. Impulsivity moderated the subjective reinforcing (liking) effects of inhaled gas, while depressive symptoms moderated motivational (wanting [more]) effects. However, depression and impulsivity had opposite directional influences, such that higher impulsivity was associated with higher N2O liking, and higher depression, with lower N2O wanting. CONCLUSION To the extent that static (versus longitudinal) subjective rewarding effects are a reliable indicator of future problematic drug use, our findings suggests that impulsivity and depression may predispose and protect, respectively, against N2O abuse. Future studies should examine if these moderators are relevant for other NMDAR antagonists, including ketamine, and novel ketamine-like therapeutic and recreational drugs. Similarities between moderate-dose N2O and moderate-dose ketamine in the intensity of certain subjective effects suggest that N2O may, at least to some extent, serve as substitute for ketamine as a safe and easily implemented experimental tool for probing reward-related NMDAR function and dysfunction in humans.
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Affiliation(s)
- Sunjeev K Kamboj
- Clinical Psychopharmacology Unit, Research Department Clinical Educational and Health Psychology, University College London, London, United Kingdom,Correspondence: Sunjeev K. Kamboj, DClinPsy, PhD, ()
| | - Hannah Zhao
- Clinical Psychopharmacology Unit, Research Department Clinical Educational and Health Psychology, University College London, London, United Kingdom
| | - Luzia Troebinger
- Clinical Psychopharmacology Unit, Research Department Clinical Educational and Health Psychology, University College London, London, United Kingdom
| | - Giulia Piazza
- Clinical Psychopharmacology Unit, Research Department Clinical Educational and Health Psychology, University College London, London, United Kingdom
| | - Emma Cawley
- Clinical Psychopharmacology Unit, Research Department Clinical Educational and Health Psychology, University College London, London, United Kingdom
| | - Vanessa Hennessy
- Clinical Psychopharmacology Unit, Research Department Clinical Educational and Health Psychology, University College London, London, United Kingdom
| | - Georges Iskandar
- Department of Anaesthesia and Perioperative Medicine, University College London Hospital, London, United Kingdom
| | - Ravi K Das
- Clinical Psychopharmacology Unit, Research Department Clinical Educational and Health Psychology, University College London, London, United Kingdom
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14
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Walsh K, Iskandar G, Kamboj SK, Das RK. An assessment of rapamycin for weakening binge-eating memories via reconsolidation: a pre-registered, double-blind randomised placebo-controlled experimental study. Psychol Med 2021; 51:158-167. [PMID: 31736460 DOI: 10.1017/s003329171900312x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Maladaptive learning linking environmental food cues to high-palatability food reward plays a central role in overconsumption in obesity and binge eating disorders. The process of memory reconsolidation offers a mechanism to weaken such learning, potentially ameliorating over-eating behaviour. Here we investigated whether putatively interfering with synaptic plasticity using the mammalian target of rapamycin (mTOR) inhibitor, rapamycin, could weaken retrieved chocolate reward memories through blockade of reconsolidation. METHODS Seventy five healthy volunteers with a tendency to binge eat chocolate were randomised to retrieve chocolate reward memory under 10 mg rapamycin (RET + RAP, active condition), or placebo (RET + PBO), or they received 10 mg rapamycin without subsequent retrieval (NO RET + RAP). Indices of chocolate reward memory strength were assessed one week pre and post manipulation and at one month follow-up. RESULTS Contrary to hypotheses, the RET + RAP group did not show any greater reduction than control groups on indices of motivational salience of chocolate cues, motivation to consume chocolate or liking of chocolate. Mild evidence of improvement in the RET + RAP group was found, but this was limited to reduced chocolate binge episodes and improved healthy food choices. CONCLUSIONS We did not find convincing evidence of comprehensive naturalistic chocolate reward memory reconsolidation blockade by rapamycin. The effects on chocolate bingeing and food choices may warrant further investigation. These limited positive findings may be attributable to insufficient interference with mTOR signalling with 10 mg rapamycin, or failure to destabilise chocolate memories during retrieval.
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Affiliation(s)
- Katie Walsh
- Clinical, Educational and Health Psychology, University College London, Gower Street, London, WC1E 6BT
| | - Georges Iskandar
- University College Hospital and University College Hospital at Westmoreland Street, London, UK
| | - Sunjeev K Kamboj
- Clinical, Educational and Health Psychology, University College London, Gower Street, London, WC1E 6BT
| | - Ravi K Das
- Clinical, Educational and Health Psychology, University College London, Gower Street, London, WC1E 6BT
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15
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Das RK, Gale G, Walsh K, Hennessy VE, Iskandar G, Mordecai LA, Brandner B, Kindt M, Curran HV, Kamboj SK. Author Correction: Ketamine can reduce harmful drinking by pharmacologically rewriting drinking memories. Nat Commun 2020; 11:3065. [PMID: 32528103 PMCID: PMC7289858 DOI: 10.1038/s41467-020-16762-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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16
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Kamboj SK, Gong AT, Sim Z, Rashid AA, Baba A, Iskandar G, Das RK, Curran HV. Reduction in the occurrence of distressing involuntary memories following propranolol or hydrocortisone in healthy women. Psychol Med 2020; 50:1148-1155. [PMID: 31084640 DOI: 10.1017/s0033291719001028] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Pharmacological treatments targeting the neuroendocrine stress response may hold special promise in secondary prevention of posttraumatic stress disorder (PTSD). However, findings from clinical trials have been inconsistent and the efficacy of specific drugs, their temporal window of efficacy, effective doses and the characteristics of likely treatment responders remain unclear. METHOD Using an experimental human model of distressing involuntary memory formation, we compare the effects of two drugs that have theoretical or empirical support as secondary preventive agents in PTSD. Eighty-eight healthy women (average age: 23.5 years) received oral propranolol (80 mg), hydrocortisone (30 mg), or matched placebo immediately after viewing a 'trauma film'. They then completed daily, time-stamped intrusion diaries for 1 week, at the end of which, voluntary memory was tested. RESULTS While neither drug affected voluntary memory for the trauma narrative, propranolol treatment was associated with 42% fewer, and hydrocortisone with 55% fewer intrusions across the week, relative to placebo. Additionally, propranolol reduced general trauma-like symptoms, and post-drug cortisol levels were negatively correlated with intrusion frequency in the hydrocortisone group. CONCLUSIONS Overall, this study shows substantial reductions in intrusive memories and preserved voluntary narrative-declarative memory following either propranolol or hydrocortisone in an experimental model of psychological trauma. As such, despite some inconsistencies in clinical trials, our findings support continued investigation of propranolol and hydrocortisone as secondary preventive agents for re-experiencing symptoms of PTSD. The findings also suggest that it is critical for future research to identify the conditions governing the preventive efficacy of these drugs in PTSD.
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Affiliation(s)
| | - An Tong Gong
- Clinical Psychopharmacology Unit, UCL, LondonWC1E 6BT, UK
| | - ZhiHui Sim
- Clinical Psychopharmacology Unit, UCL, LondonWC1E 6BT, UK
| | | | - Ami Baba
- Clinical Psychopharmacology Unit, UCL, LondonWC1E 6BT, UK
| | - Georges Iskandar
- Department of Anaesthesia and Perioperative Medicine, UCLH, London, UK
| | - Ravi K Das
- Clinical Psychopharmacology Unit, UCL, LondonWC1E 6BT, UK
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17
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Serpell L, Amey R, Kamboj SK. The role of self-compassion and self-criticism in binge eating behaviour. Appetite 2020; 144:104470. [PMID: 31586596 DOI: 10.1016/j.appet.2019.104470] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 09/23/2019] [Accepted: 09/23/2019] [Indexed: 11/25/2022]
Abstract
Self-criticism and low self-compassion are implicated in the development and maintenance of binge eating. However, the association between these self-attitudes and binge eating symptoms remains unclear. Women with symptoms of Bulimia Nervosa (BN) or Binge Eating Disorder (BED) were randomised to either a self-compassion (n = 30) or self-critical rumination (n = 30) strategy following a negative mood induction. Responses to food cues (cue reactivity and affect) and calorie consumption in a 'taste test' were assessed. The self-compassion strategy was associated with a greater improvement in positive and negative affect following the negative mood induction. Despite the differential effects on mood, self-compassion and self-critical rumination led to similar self-reported food cravings and physiological reactivity to cues. However, participants in the self-compassion condition consumed significantly fewer calories, rated the consumed food as less pleasurable, and reported less desire to continue eating. The findings suggest that therapeutic strategies for cultivating self-compassion are associated with improved food-related self-regulation in the context of negative mood.
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Affiliation(s)
- Lucy Serpell
- Eating Disorder Service, North East London Foundation Trust, Essex, UK; Research Dept of Clinical, Educational & Health Psychology, University College London, UK.
| | - Rebecca Amey
- Research Dept of Clinical, Educational & Health Psychology, University College London, UK
| | - Sunjeev K Kamboj
- Research Dept of Clinical, Educational & Health Psychology, University College London, UK
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Paulus DJ, Kamboj SK, Das RK, Saladin ME. Prospects for reconsolidation-focused treatments of substance use and anxiety-related disorders. Curr Opin Psychol 2019; 30:80-86. [PMID: 30986617 DOI: 10.1016/j.copsyc.2019.03.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 02/12/2019] [Accepted: 03/05/2019] [Indexed: 11/19/2022]
Abstract
Memories are often conceptualized as permanent entities; however, retrieval of memories via stimulus prompts can return them to an active state, which initiates a period of lability before the memories are reconsolidated into long-term storage. Importantly, during this period, memories can be disrupted/altered. A growing body of work has focused on translating animal and experimental science into reconsolidation-based interventions for clinical disorders maintained by maladaptive memories. Interventions targeting reward-based and fear-based memories undergirding substance use and anxiety-related disorders, respectively, have shown significant potential. There are several promising pharmacological agents and behavioral approaches that have been used to therapeutically target memory reconsolidation. Here, we discuss the current state of science with special emphasis on the clinical utility of these approaches.
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Affiliation(s)
- Daniel J Paulus
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA; Department of Psychology, University of Houston, Houston, TX, USA
| | - Sunjeev K Kamboj
- Clinical Psychopharamacology Unit, Research Department of Clinical, Educational, and Health Psychology, University College London, London, UK
| | - Ravi K Das
- Clinical Psychopharamacology Unit, Research Department of Clinical, Educational, and Health Psychology, University College London, London, UK
| | - Michael E Saladin
- Department of Psychiatry and Behavioral Sciences, Medical University of South Carolina, Charleston, SC, USA; Department of Health Sciences and Research, College of Health Professions, Medical University of South Carolina Charleston, SC, USA.
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19
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Falconer CJ, Lobmaier JS, Christoforou M, Kamboj SK, King JA, Gilbert P, Brewin CR. Compassionate faces: Evidence for distinctive facial expressions associated with specific prosocial motivations. PLoS One 2019; 14:e0210283. [PMID: 30673735 PMCID: PMC6343863 DOI: 10.1371/journal.pone.0210283] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 12/19/2018] [Indexed: 01/18/2023] Open
Abstract
Compassion is a complex cognitive, emotional and behavioural process that has important real-world consequences for the self and others. Considering this, it is important to understand how compassion is communicated. The current research investigated the expression and perception of compassion via the face. We generated exemplar images of two compassionate facial expressions induced from two mental imagery tasks with different compassionate motivations (Study 1). Our kind- and empathic compassion faces were perceived differently and the empathic-compassion expression was perceived as best depicting the general definition of compassion (Study 2). Our two composite faces differed in their perceived happiness, kindness, sadness, fear and concern, which speak to their underling motivation and emotional resonance. Finally, both faces were accurately discriminated when presented along a compassion continuum (Study 3). Our results demonstrate two perceptually and functionally distinct facial expressions of compassion, with potentially different consequences for the suffering of others.
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Affiliation(s)
- Caroline J. Falconer
- Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
| | | | - Marina Christoforou
- Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
| | - Sunjeev K. Kamboj
- Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
| | - John A. King
- Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
| | - Paul Gilbert
- Mental Health Research Unit, University of Derby, Derby, United Kingdom
| | - Chris R. Brewin
- Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
- * E-mail:
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20
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Platt B, O'Driscoll C, Curran VH, Rendell PG, Kamboj SK. The effects of licit and illicit recreational drugs on prospective memory: a meta-analytic review. Psychopharmacology (Berl) 2019; 236:1131-1143. [PMID: 31093722 PMCID: PMC6591206 DOI: 10.1007/s00213-019-05245-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 04/09/2019] [Indexed: 11/25/2022]
Abstract
RATIONALE There are no recent reports summarising the magnitude of prospective memory (PM) impairments in recreational drug users. OBJECTIVE We performed a meta-analysis of studies (with a parallel group design) examining PM performance in users of common recreational drugs (including alcohol and tobacco) who were not intoxicated during testing. Studies were also evaluated for the presence of methodological bias. METHODS Twenty-seven studies were included in the meta-analysis following literature searches of MEDLINE, EMBASE and PsycINFO. Effect sizes (standardised mean difference; SMD) were calculated separately for the effects of alcohol, cannabis, ecstasy, methamphetamine and tobacco use. The influences of drug use and study characteristics on effect sizes were explored using meta-regressions. Sources of study bias were also assessed. RESULTS Heavy drinkers and regular drug users tended to perform worse than controls on event and time-based PM tasks. Effect sizes (standardised mean differences; SMDs) for event-based PM impairment across the different drug-using groups/heavy drinkers ranged between - 1.10 and - 0.49, with no 95% CI crossing 0.00. SMDs for time-based PM ranged between - 0.98 and - 0.70. Except for the CIs associated with the ES for smokers' time-based PM performance, no CIs crossed 0.00. CONCLUSIONS Although all drug-using groups showed moderate-large impairments in event and time-based PM, effect sizes had low precision and moderate-high levels of heterogeneity. In addition, several methodological and reporting issues were identified in the majority of studies. As such, considerable uncertainty remains regarding the role of confounds and the magnitude of PM impairments in non-intoxicated recreational drug users.
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Affiliation(s)
- Bradley Platt
- Clinical Psychopharmacology Unit, University College London, London, UK.
| | - Ciarán O'Driscoll
- Institute of Cognitive Neuroscience, University College London, London, UK
| | - Valerie H Curran
- Clinical Psychopharmacology Unit, University College London, London, UK
| | - Peter G Rendell
- Cognition and Emotion Research Centre, Australian Catholic University, Melbourne, Australia
| | - Sunjeev K Kamboj
- Clinical Psychopharmacology Unit, University College London, London, UK
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Gong AT, Kamboj SK, Curran HV. Post-traumatic Stress Disorder in Victims of Sexual Assault With Pre-assault Substance Consumption: A Systematic Review. Front Psychiatry 2019; 10:92. [PMID: 30918487 PMCID: PMC6424881 DOI: 10.3389/fpsyt.2019.00092] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Accepted: 02/08/2019] [Indexed: 11/13/2022] Open
Abstract
Background: Post-traumatic stress disorder (PTSD) and substance consumption commonly co-occur in victims of sexual assault. Substance consumption can occur pre- andi/or post-assault. Pre-assault substance consumption may have an impact on the subsequent development of PTSD. This review aims to provide an overview of current understanding of the effects of acute substance intoxication and chronic pre-assault problematic substance use on symptoms of PTSD amongst individuals who were victims of sexual assault. Methods: PsycINFO, EMBASE, and MEDLINE were searched using terms related to PTSD, sexual assault, and substance consumption. These yielded 2,121 articles, 268 of which were retrieved for more detailed evaluation and 13 of these met inclusion criteria and were appraised in full. Results: Overall, the reviewed papers supported our hypothesis that acute substance intoxication and chronic pre-assault problematic substance use are associated with fewer initial PTSD symptoms but less improvement over time, resulting in slower overall PTSD recovery. They also highlighted post-assault characterological self-blame and negative social reactions as mediators of recovery in the context of pre-assault substance consumption. Conclusions: Acute substance intoxication and chronic pre-assault problematic substance use appear to have an impact on the development of PTSD symptoms amongst victims of sexual assault. The importance of developing early interventions and routine screening and assessment for PTSD and pre-assault substance consumption is emphasized. The limited research on male victims and on substances other than alcohol is highlighted.
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Affiliation(s)
- An Tong Gong
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
| | - Sunjeev K Kamboj
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
| | - Helen Valerie Curran
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
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Walsh KH, Das RK, Saladin ME, Kamboj SK. Modulation of naturalistic maladaptive memories using behavioural and pharmacological reconsolidation-interfering strategies: a systematic review and meta-analysis of clinical and 'sub-clinical' studies. Psychopharmacology (Berl) 2018; 235:2507-2527. [PMID: 30091003 PMCID: PMC6132663 DOI: 10.1007/s00213-018-4983-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 07/23/2018] [Indexed: 12/13/2022]
Abstract
BACKGROUND Consolidated memories can undergo enduring modification through retrieval-dependent treatments that modulate reconsolidation. This represents a potentially transformative strategy for weakening or overwriting the maladaptive memories that underlie substance use and anxiety/trauma-related disorders. However, modulation of naturalistic maladaptive memories may be limited by 'boundary conditions' imposed on the reconsolidation process by the nature of these memories. METHODS We conducted a systematic review and meta-analyses of behavioural and pharmacological studies examining retrieval-dependent modulation of reward- and threat-related memories in (sub) clinical substance use and anxiety/trauma, respectively. RESULTS Of 4938 publications assessed for eligibility, 8 studies of substance use and 10 of anxiety (phobia)- and trauma-related symptoms were included in the meta-analyses. Overall, the findings were in the predicted direction, with most studies favouring the 'retrieval + treatment' condition. However, the magnitude of effects was dependent upon the nature of treatment, with pharmacological interventions showing a medium-sized effect (g = 0.59, p = 0.03) and behavioural treatments, a relatively small effect (g = 0.32, p = 0.10) in studies of phobia/trauma. Among studies of substance use, post-retrieval behavioural interventions yielded a larger effect (g = 0.60, p < 0.001) relative to pharmacological treatments (g = - 0.03, p = 0.91), with treatment type being a statistically significant moderator (χ2(1) = 4.20, p = 0.04). CONCLUSION Modification of naturalistic maladaptive memories during reconsolidation appears to be a viable treatment strategy for substance use and phobias/trauma disorders. However, high levels of heterogeneity and methodological variation limit the strength of conclusions that can be drawn from the reviewed studies at this stage.
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Affiliation(s)
- Katie H Walsh
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Ravi K Das
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Michael E Saladin
- Department of Health Sciences and Research, College of Health Professions, Medical University of South Carolina, Charleston, USA
| | - Sunjeev K Kamboj
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, Gower Street, London, WC1E 6BT, UK.
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Kamboj SK, Walldén YSE, Falconer CJ, Alotaibi MR, Blagbrough IS, Husbands SM, Freeman TP. Additive Effects of 3,4-Methylenedioxymethamphetamine (MDMA) and Compassionate Imagery on Self-Compassion in Recreational Users of Ecstasy. Mindfulness (N Y) 2018; 9:1134-1145. [PMID: 30100932 PMCID: PMC6061231 DOI: 10.1007/s12671-017-0849-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
3,4-Methylenedioxymethylamphetamine (MDMA;‘ecstasy’) produces prosocial subjective effects that may extend to affiliative feelings towards the self. Behavioural techniques can produce similar self-directed affiliation. For example, compassionate imagery (CI) and ecstasy reduce self-criticism and increase self-compassion to a similar extent, with the effects of CI enhanced in the presence of ecstasy. Here, we examine self-compassion and self-criticism in recreational users who consumed chemically verified MDMA in a within-subjects crossover study. In a naturalistic setting, polydrug-using participants performed a self-focused CI exercise on two occasions separated by ≥6 days: once having consumed self-sourced MDMA and once not. Effects on state self-criticism, self-compassion and emotional empathy were assessed before and after MDMA use (or over an extended baseline period on the occasion that MDMA was not consumed) and reassessed after CI. In participants (n = 20; 8 women) whose ecstasy contained MDMA and no other drug, CI and MDMA appeared to separately increase emotional empathy (to critical facial expressions) and self-compassion. The effects of CI and MDMA on self-compassion also appeared to be additive. Establishing the observed effects in controlled studies will be critical for determining the combined utility of these approaches in fostering adaptive self-attitudes in a therapeutic context.
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Affiliation(s)
- Sunjeev K Kamboj
- 1Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, Gower St., London, WC1E 6BT UK
| | - Ylva S E Walldén
- 1Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, Gower St., London, WC1E 6BT UK
| | - Caroline J Falconer
- 1Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, Gower St., London, WC1E 6BT UK
| | - Majdah Raji Alotaibi
- 2Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Bath, BA2 7AY UK
| | - Ian S Blagbrough
- 2Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Bath, BA2 7AY UK
| | - Stephen M Husbands
- 2Medicinal Chemistry, Department of Pharmacy and Pharmacology, University of Bath, Bath, BA2 7AY UK
| | - Tom P Freeman
- 1Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, Gower St., London, WC1E 6BT UK.,3Present Address: National Addiction Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 4 Windsor Walk, London, SE5 8BB UK
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Das RK, Walsh K, Hannaford J, Lazzarino AI, Kamboj SK. Nitrous oxide may interfere with the reconsolidation of drinking memories in hazardous drinkers in a prediction-error-dependent manner. Eur Neuropsychopharmacol 2018; 28:828-840. [PMID: 29887289 DOI: 10.1016/j.euroneuro.2018.05.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 01/29/2018] [Accepted: 05/17/2018] [Indexed: 12/16/2022]
Abstract
Weakening drinking-related reward memories by blocking their reconsolidation is a potential novel strategy for treating alcohol use disorders. However, few viable pharmacological options exist for reconsolidation interference in humans. We therefore examined whether the NMDA receptor antagonising gas, Nitrous Oxide (N2O) could reduce drinking by preventing the post-retrieval restabilisation of alcohol memories in a group of hazardous drinkers. Critically, we focussed on whether prediction error (PE; a key determinant of reconsolidation) was experienced at retrieval. Sixty hazardous drinkers were randomised to one of three groups that retrieved alcohol memories either with negative PE (Retrieval + PE), no PE (Retrieval no PE) or non-alcohol memory retrieval with PE (No-retrieval +PE). All participants then inhaled 50% N2O for 30 min. The primary outcome was change in beer consumption and alcohol cue-driven urge to drink from the week preceding manipulation (baseline) to the week following manipulation (test). The manipulation did not affect drinking following the intended retrieval+/- PE conditions However, a manipulation check, using a measure of subjective surprise, revealed that the group-level manipulation did not achieve the intended differences in PE at retrieval. Assessment of outcomes according to whether alcohol-relevant PE was actually experienced at retrieval, showed N2O produced reductions in drinking in a retrieval and PE-dependent fashion. These preliminary findings highlight the importance of directly testing assumptions about memory reactivation procedures in reconsolidation research and suggest that N2O should be further investigated as a potential reconsolidation-blocking agent.
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Affiliation(s)
- R K Das
- Clinical Psychopharmacology Unit, University College London, 1-19 Torrington Place, London WC1E 7HB, United Kingdom; Educational Psychology, Clinical, Educational and Health Psychology, University College London, 26 Bedford Way, London WC1H 0AP, United Kingdom.
| | - K Walsh
- Clinical Psychopharmacology Unit, University College London, 1-19 Torrington Place, London WC1E 7HB, United Kingdom
| | - J Hannaford
- Clinical Psychopharmacology Unit, University College London, 1-19 Torrington Place, London WC1E 7HB, United Kingdom
| | - A I Lazzarino
- Department of Epidemiology and Public Health, UCL, 1-19 Torrington Place, London WC1E 7HB, United Kingdom
| | - S K Kamboj
- Clinical Psychopharmacology Unit, University College London, 1-19 Torrington Place, London WC1E 7HB, United Kingdom
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Das RK, Gale G, Hennessy V, Kamboj SK. A Prediction Error-driven Retrieval Procedure for Destabilizing and Rewriting Maladaptive Reward Memories in Hazardous Drinkers. J Vis Exp 2018. [PMID: 29364255 PMCID: PMC5908434 DOI: 10.3791/56097] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Maladaptive reward memories (MRMs) can become unstable following retrieval under certain conditions, allowing their modification by subsequent new learning. However, robust (well-rehearsed) and chronologically old MRMs, such as those underlying substance use disorders, do not destabilize easily when retrieved. A key determinate of memory destabilization during retrieval is prediction error (PE). We describe a retrieval procedure for alcohol MRMs in hazardous drinkers that specifically aims to maximize the generation of PE and therefore the likelihood of MRM destabilization. The procedure requires explicitly generating the expectancy of alcohol consumption and then violating this expectancy (withholding alcohol) following the presentation of a brief set of prototypical alcohol cue images (retrieval + PE). Control procedures involve presenting the same cue images, but allow alcohol to be consumed, generating minimal PE (retrieval-no PE) or generate PE without retrieval of alcohol MRMs, by presenting orange juice cues (no retrieval + PE). Subsequently, we describe a multisensory disgust-based counterconditioning procedure to probe MRM destabilization by re-writing alcohol cue-reward associations prior to reconsolidation. This procedure pairs alcohol cues with images invoking pathogen disgust and an extremely bitter-tasting solution (denatonium benzoate), generating gustatory disgust. Following retrieval + PE, but not no retrieval + PE or retrieval-no PE, counterconditioning produces evidence of MRM rewriting as indexed by lasting reductions in alcohol cue valuation, attentional capture, and alcohol craving.
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Affiliation(s)
- Ravi K Das
- Clinical Psychopharmacology Unit, University College London;
| | - Grace Gale
- Clinical Psychopharmacology Unit, University College London
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Braidwood R, Mansell S, Waldron J, Rendell PG, Kamboj SK, Curran HV. Non-Dependent and Dependent Daily Cannabis Users Differ in Mental Health but Not Prospective Memory Ability. Front Psychiatry 2018; 9:97. [PMID: 29636705 PMCID: PMC5880932 DOI: 10.3389/fpsyt.2018.00097] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 03/09/2018] [Indexed: 11/13/2022] Open
Abstract
Research suggests that daily cannabis users have impaired memory for past events, but it is not clear whether they are also impaired in prospective memory (PM) for future events. The present study examined PM in daily cannabis users who were either dependent (n = 18) or non-dependent (n = 18), and compared them with non-using controls (n = 18). The effect of future event simulation (FES) on PM performance was also examined. Participants were matched across groups on age, gender, and highest level of education. The virtual week (VW) was used to objectively assess PM abilities, both at baseline and following FES. Other measures used were: cannabis use variables, immediate and delayed prose recall, phonemic and category fluency, spot-the-word test (premorbid intelligence), Beck Depression Inventory, Beck Anxiety Inventory, and a measure of schizotypy (Oxford-Liverpool Inventory of Feelings and Experiences: unusual experiences subscale). No group differences were found in PM performance on the VW, and FES did not improve PM performance in any group. Dependent cannabis users scored higher on depression, anxiety, and schizotypy than both other groups with non-dependent cannabis users scoring at a similar level to controls. There were no group differences in alcohol use. Findings suggest that when carefully matched on baseline variables, and not differing in premorbid IQ or alcohol use, young, near-daily cannabis users do not differ from non-using controls in PM performance.
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Affiliation(s)
- Ruth Braidwood
- Clinical Psychopharmacology Unit (CPU), University College London, London, United Kingdom
| | - Samantha Mansell
- Clinical Psychopharmacology Unit (CPU), University College London, London, United Kingdom
| | - Jon Waldron
- Clinical Psychopharmacology Unit (CPU), University College London, London, United Kingdom
| | - Peter G Rendell
- Cognition and Emotion Research Centre, Australian Catholic University, Melbourne, VIC, Australia
| | - Sunjeev K Kamboj
- Clinical Psychopharmacology Unit (CPU), University College London, London, United Kingdom
| | - H Valerie Curran
- Clinical Psychopharmacology Unit (CPU), University College London, London, United Kingdom
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Kamboj SK, Irez D, Serfaty S, Thomas E, Das RK, Freeman TP. Ultra-Brief Mindfulness Training Reduces Alcohol Consumption in At-Risk Drinkers: A Randomized Double-Blind Active-Controlled Experiment. Int J Neuropsychopharmacol 2017; 20:936-947. [PMID: 29016995 PMCID: PMC5737497 DOI: 10.1093/ijnp/pyx064] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2017] [Revised: 07/18/2017] [Accepted: 07/28/2017] [Indexed: 02/04/2023] Open
Abstract
Background Like other complex psychosocial interventions, mindfulness-based treatments comprise various modality-specific components as well as nonspecific therapeutic ingredients that collectively contribute to efficacy. Consequently, the isolated effects of mindfulness strategies per se remain unclear. Methods Using a randomized double-blind design, we compared the isolated effects of 11-minutes of "supervised" mindfulness instruction against a closely matched active control (relaxation) on subjective, physiological, and behavioral indices of maladaptive alcohol responding in drinkers at risk of harm from alcohol use (n = 68). Simple follow-up instructions on strategy use were provided, but practice was unsupervised and not formally monitored. Results Both groups showed acute reductions in craving after training, although a trend group x time interaction (P = .056) suggested that this reduction was greater in the relaxation group (d = 0.722 P < .001) compared with the mindfulness group (d = 0.317, P = .004). Furthermore, upregulation of parasympathetic activity was found after relaxation (d = 0.562; P < .001) but not mindfulness instructions (d = 0.08; P > .1; group x time interaction: P = .009). By contrast, only the mindfulness group showed a reduction in past-week alcohol consumption at 7-day follow-up (-9.31 units, d = 0.593, P < .001), whereas no significant reduction was seen in the relaxation group (-3.00 units, d = 0.268, P > .1; group x time interaction: P = .026). Conclusion Very brief mindfulness practice can significantly reduce alcohol consumption among at-risk drinkers, even with minimal encouragement to use this strategy outside of the experimental context. The effects on consumption may therefore represent a lower bound of efficacy of "ultra-brief" mindfulness instructions in hazardous drinkers, at least at short follow-up intervals.
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Affiliation(s)
- Sunjeev K Kamboj
- Clinical Psychopharmacology Unit (Dr Kamboj, Ms Thomas, and Drs Das and Freeman); Research Department of Clinical, Educational and Health Psychology (Drs Kamboj, Irez, and Serfaty, Ms Thomas, and Drs Das and Freeman), University College London, United Kingdom
| | - Damla Irez
- Clinical Psychopharmacology Unit (Dr Kamboj, Ms Thomas, and Drs Das and Freeman); Research Department of Clinical, Educational and Health Psychology (Drs Kamboj, Irez, and Serfaty, Ms Thomas, and Drs Das and Freeman), University College London, United Kingdom
| | - Shirley Serfaty
- Clinical Psychopharmacology Unit (Dr Kamboj, Ms Thomas, and Drs Das and Freeman); Research Department of Clinical, Educational and Health Psychology (Drs Kamboj, Irez, and Serfaty, Ms Thomas, and Drs Das and Freeman), University College London, United Kingdom
| | - Emily Thomas
- Clinical Psychopharmacology Unit (Dr Kamboj, Ms Thomas, and Drs Das and Freeman); Research Department of Clinical, Educational and Health Psychology (Drs Kamboj, Irez, and Serfaty, Ms Thomas, and Drs Das and Freeman), University College London, United Kingdom
| | - Ravi K Das
- Clinical Psychopharmacology Unit (Dr Kamboj, Ms Thomas, and Drs Das and Freeman); Research Department of Clinical, Educational and Health Psychology (Drs Kamboj, Irez, and Serfaty, Ms Thomas, and Drs Das and Freeman), University College London, United Kingdom
| | - Tom P Freeman
- Clinical Psychopharmacology Unit (Dr Kamboj, Ms Thomas, and Drs Das and Freeman); Research Department of Clinical, Educational and Health Psychology (Drs Kamboj, Irez, and Serfaty, Ms Thomas, and Drs Das and Freeman), University College London, United Kingdom
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Abstract
The psychological flexibility model (PFM) provides a framework for understanding and treating behavioural dysregulation in addictions. Rather than modulating the intensity of subjective experience, interventions based on, or consistent with, the PFM (PFM interventions) seek to alter the individual's relationship to internal states, such as craving, negative affect and drug-related thoughts, using mindfulness, acceptance and related strategies. Experimental (non-clinical) studies in smokers have examined the effects of specific isolated strategies informed by or consistent with the PFM (PFM strategies). Here, we systematically review these studies and determine the extent to which they conform to methodological standards indicative of high levels of internal validity. Eligible studies were identified through electronic database searches and assessed for the presence of specific methodological features. Provisional aggregate effect sizes were determined depending on availability of data. Of 1499 screened publications, 12 met the criteria. All examined aspects of private subjective experience relevant to abstinence (craving n = 12; negative affect n = 10), demonstrating effects favouring PFM strategies relative to inactive control conditions. However, only six assessed outcome domains consistent with the PFM and provided no consistent evidence favouring PFM strategies. Overall, most studies had methodological limitations. As such, high-quality experimental studies continue to be needed to improve our understanding of necessary and/or sufficient constituents of PFM-guided smoking cessation interventions. Recommendations for future research are discussed.
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Affiliation(s)
- Shirley Serfaty
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Grace Gale
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Matthew Beadman
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Brett Froeliger
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC USA
| | - Sunjeev K Kamboj
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
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Kamboj SK, Das RK. Behavioral and Pharmacological Strategies for Weakening Maladaptive Reward Memories: A New Approach to Treating a Core Disease Mechanism in Tobacco Use Disorder. JAMA Psychiatry 2017; 74:209-211. [PMID: 28146262 DOI: 10.1001/jamapsychiatry.2016.3937] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Sunjeev K Kamboj
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, England
| | - Ravi K Das
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, England
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Wallace-Hadrill SMA, Kamboj SK. The Impact of Perspective Change As a Cognitive Reappraisal Strategy on Affect: A Systematic Review. Front Psychol 2016; 7:1715. [PMID: 27867366 PMCID: PMC5095639 DOI: 10.3389/fpsyg.2016.01715] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 10/18/2016] [Indexed: 11/13/2022] Open
Abstract
The strategic or deliberate adoption of a cognitively distanced, third-person perspective is proposed to adaptively regulate emotions. However, studies of psychological disorders suggest spontaneous adoption of a third-person perspective reflects counter-productive avoidance. Here, we review studies that investigate the deliberate adoption of a third- or first-person vantage perspective and its impact on affect in healthy people, “sub-clinical” populations and those with psychological disorders. A systematic search was conducted across four databases. After exclusion criteria were applied, 38 studies were identified that investigated the impact of both imagery and verbal instructions designed to encourage adoption of a third-person perspective on self-reported affect. The identified studies examined a variety of outcomes related to recalling memories, imagining scenarios and mood induction. These were associated with specific negative emotions or mood states (dysphoria/sadness, anxiety, anger), mixed or neutral affect autobiographical memories, and self-conscious affect (e.g., guilt). Engaging a third-person perspective was generally associated with a reduction in the intensity of positive and negative affect. Studies that included measures of semantic change, suggested that this is a key mediator in reduction of affect following perspective change. Strategically adopting a “distanced,” third-person perspective is linked to a reduction in affect intensity across valence, but in addition has the potential to introduce new information that regulates emotion via semantic change. Such reappraisal distinguishes deliberate adoption of a distanced perspective from the habitual and/or spontaneous shift in perspective that occurs in psychopathology.
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Affiliation(s)
- Sophie M A Wallace-Hadrill
- East London National Health Service Foundation TrustLondon, UK; Research Department of Clinical, Educational and Health Psychology, University College LondonLondon, UK
| | - Sunjeev K Kamboj
- Research Department of Clinical, Educational and Health Psychology, University College London London, UK
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Moss A, Curran HV, Bloomfield MAP, Kamboj SK, Blackwell SE, Freeman TP. Bringing together pharmacological and psychological approaches to mental health research. Lancet Psychiatry 2016; 3:700-702. [PMID: 27475758 DOI: 10.1016/s2215-0366(16)30080-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 04/22/2016] [Accepted: 04/22/2016] [Indexed: 11/27/2022]
Affiliation(s)
- Abigail Moss
- Clinical Psychopharmacology Unit, University College London, WC1E 6BT, UK
| | - H Valerie Curran
- Clinical Psychopharmacology Unit, University College London, WC1E 6BT, UK
| | - Michael A P Bloomfield
- Division of Psychiatry, University College London, UK; Psychiatric Imaging Group, MRC Clinical Sciences Centre, London, UK
| | - Sunjeev K Kamboj
- Clinical Psychopharmacology Unit, University College London, WC1E 6BT, UK
| | - Simon E Blackwell
- MRC Cognition & Brain Sciences Unit, Cambridge, UK; Mental Health Research and Treatment Centre, Department of Psychology, Ruhr-Universität Bochum, Germany
| | - Tom P Freeman
- Clinical Psychopharmacology Unit, University College London, WC1E 6BT, UK.
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Walsh K, Das RK, Kamboj SK. The Subjective Response to Nitrous Oxide is a Potential Pharmaco-Endophenotype for Alcohol Use Disorder: A Preliminary Study with Heavy Drinkers. Int J Neuropsychopharmacol 2016; 20:346-350. [PMID: 27401180 PMCID: PMC5409036 DOI: 10.1093/ijnp/pyw063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 07/07/2016] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND Healthy people with a family history of alcohol problems show a pattern of subjective responses to alcohol that resemble those of affected probands. Studies on ketamine suggest that up-regulation of N-methyl-D-aspartate receptors (NMDARs) underlies these effects, and point to a pharmacologically-responsive endophenotype reflecting enhanced risk for alcohol-use disorders. METHODS Subjective stimulant and sedative effects were assessed before and during nitrous oxide (N2O; 50%) inhalation in heavy drinkers who were otherwise healthy. RESULTS Participants with an ostensible family history of alcohol-use disorders (n = 23) were distinguishable from those without such familial risk (n = 37) by an enhanced stimulation-to-sedation ratio during N2O inhalation. CONCLUSION The pattern of subjective effects of N2O according to familial risk is remarkably similar to that previously seen with ketamine, supporting the idea of a common, NMDAR-mediated mechanism of action. N2O may prove to be a safe and accessible alternative to ketamine for probing heritable NMDAR dysregulation in neuropsychiatric disorders.
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Affiliation(s)
- Katie Walsh
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, Gower Street, London
| | - Ravi K Das
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, Gower Street, London
| | - Sunjeev K Kamboj
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, Gower Street, London
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Das RK, Tamman A, Nikolova V, Freeman TP, Bisby JA, Lazzarino AI, Kamboj SK. Nitrous oxide speeds the reduction of distressing intrusive memories in an experimental model of psychological trauma. Psychol Med 2016; 46:1749-1759. [PMID: 26937942 DOI: 10.1017/s003329171600026x] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND Post-traumatic stress disorder (PTSD) involves maladaptive long-term memory formation which underlies involuntary intrusive thoughts about the trauma. Preventing the development of such maladaptive memory is a key aim in preventing the development of PTSD. We examined whether the N-methyl d-aspartate receptor (NMDAR) antagonist gas nitrous oxide (N2O) could reduce the frequency of intrusive memories by inhibiting NMDAR-dependent memory consolidation in a laboratory analogue of psychological trauma. METHOD Participants were randomized to inhale N2O (N = 25) or medical air (N = 25) after viewing a negatively valenced emotional film clip ('trauma film'). Participants subsequently completed a daily diary assessing frequency of intrusive thoughts relating to the film clip. A week later, participants completed an explicit memory recall task related to the film. RESULTS Post-encoding N2O sped the reduction in intrusive memory frequency, with a significant reduction by the next day in the N2O group compared to 4 days later in the air group. N2O also interacted with post-film dissociation, producing increased intrusion frequency in those who were highly dissociated at baseline. Sleep length and quality the night after viewing the film did not differ between the groups. CONCLUSION N2O speeds the reduction of intrusive analogue trauma memory in a time-dependent manner, consistent with sleep-dependent long-term consolidation disruption. Further research with this drug is warranted to determine its potential to inoculate against enduring effects of psychological trauma; however, caution is also urged in dissociated individuals where N2O may aggravate PTSD-like symptomatology.
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Affiliation(s)
- R K Das
- Clinical Psychopharmacology Unit,UCL,London,UK
| | - A Tamman
- Clinical Psychopharmacology Unit,UCL,London,UK
| | - V Nikolova
- Clinical Psychopharmacology Unit,UCL,London,UK
| | - T P Freeman
- Clinical Psychopharmacology Unit,UCL,London,UK
| | - J A Bisby
- Institute of Cognitive Neuroscience,UCL,London,UK
| | - A I Lazzarino
- London School of Hygiene & Tropical Medicine,London,UK
| | - S K Kamboj
- Clinical Psychopharmacology Unit,UCL,London,UK
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Kamboj SK, Place H, Barton JA, Linke S, Curran HV, Harris PR. Processing of Alcohol-Related Health Threat in At-Risk Drinkers: An Online Study of Gender-Related Self-Affirmation Effects. Alcohol Alcohol 2016; 51:756-762. [PMID: 26993737 DOI: 10.1093/alcalc/agw013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Accepted: 02/23/2016] [Indexed: 01/06/2023] Open
Abstract
AIMS Defensiveness in response to threatening health information related to excessive alcohol consumption prevents appropriate behaviour change. Alternatively, self-affirmation may improve cognitive-affective processing of threatening information, thus contributing to successful self-regulation. METHODS Effects of an online self-affirmation procedure were examined in at-risk university student drinkers. Participants were randomly assigned to a self-affirmation (writing about personally relevant values) or control task (writing about values relevant to another person) prior to presentation of alcohol-related threatening information. Assessment of prosocial feelings (e.g. 'love') after the task served as a manipulation check. Generic and personalized information regarding the link between alcohol use and cancer was presented, followed by assessment of perceived threat, message avoidance and derogation. Page dwell-times served as indirect indices of message engagement. Alcohol consumption and intention to drink less were assessed during the first online session and at 1-week and 1-month follow-up. RESULTS Although self-affirmation resulted in higher levels of prosocial feelings immediately after the task, there was no effect on behaviour in the self-affirmation group. Effects on intention were moderated by gender, such that men showed lower intention immediately after self-affirmation, but this increased at 1-week follow-up. Women's intention to reduce consumption in the self-affirmation group reduced over time. Trend-level effects on indices of derogation and message acceptance were in the predicted direction only in men. CONCLUSION It is feasible to perform self-affirmation procedures in an online environment with at-risk drinkers. However, use of internet-based procedures with this population may give rise to (gender-dependent) effects that are substantially diluted compared with lab-based experiments.
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Affiliation(s)
- Sunjeev K Kamboj
- Research Department of Clinical Educational and Health Psychology, University College London, London, UK
| | - Hannah Place
- Research Department of Clinical Educational and Health Psychology, University College London, London, UK
| | - Jessica A Barton
- Research Department of Clinical Educational and Health Psychology, University College London, London, UK
| | - Stuart Linke
- eHealth Unit, Research Department of Primary Care and Population Health, University College London, London, UK
| | - H Valerie Curran
- Research Department of Clinical Educational and Health Psychology, University College London, London, UK
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Hon T, Das RK, Kamboj SK. The effects of cognitive reappraisal following retrieval-procedures designed to destabilize alcohol memories in high-risk drinkers. Psychopharmacology (Berl) 2016; 233:851-61. [PMID: 26667478 PMCID: PMC4751186 DOI: 10.1007/s00213-015-4164-y] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 11/18/2015] [Indexed: 10/25/2022]
Abstract
RATIONALE Addiction is a disorder of motivational learning and memory. Maladaptive motivational memories linking drug-associated stimuli to drug seeking are formed over hundreds of reinforcement trials and accompanied by aberrant neuroadaptation in the mesocorticolimbic reward system. Such memories are resistant to extinction. However, the discovery of retrieval-dependent memory plasticity has opened up the possibility of permanent modification of established (long-term) memories during 'reconsolidation'. OBJECTIVES Here, we investigate whether reappraisal of maladaptive alcohol cognitions performed after procedures designed to destabilize alcohol memory networks affected subsequent alcohol memory, craving, drinking and attentional bias. METHODS Forty-seven at-risk drinkers attended two sessions. On the first lab session, participants underwent one of two prediction error-generating procedures in which outcome expectancies were violated while retrieving alcohol memories (omission and value prediction error groups). Participants in a control group retrieved non-alcohol memories. Participants then reappraised personally relevant maladaptive alcohol memories and completed measures of reappraisal recall, alcohol verbal fluency and craving. Seven days later, they repeated these measures along with attentional bias assessment. RESULTS Omission prediction error (being unexpectedly prevented from drinking beer), but not a value prediction error (drinking unexpectedly bitter-tasting beer) or control procedure (drinking unexpectedly bitter orange juice), was associated with significant reductions in verbal fluency for positive alcohol-related words. No other statistically robust outcomes were detected. CONCLUSIONS This study provides partial preliminary support for the idea that a common psychotherapeutic strategy used in the context of putative memory retrieval-destabilization can alter accessibility of alcohol semantic networks. Further research delineating the necessary and sufficient requirements for producing alterations in alcohol memory performance based on memory destabilization is still required.
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Affiliation(s)
- Tiffany Hon
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, WC1E 6BT UK
| | - Ravi K. Das
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, WC1E 6BT UK
| | - Sunjeev K. Kamboj
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, London, WC1E 6BT UK
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Kamboj SK, Kilford EJ, Minchin S, Moss A, Lawn W, Das RK, Falconer CJ, Gilbert P, Curran HV, Freeman TP. Recreational 3,4-methylenedioxy-N-methylamphetamine (MDMA) or 'ecstasy' and self-focused compassion: Preliminary steps in the development of a therapeutic psychopharmacology of contemplative practices. J Psychopharmacol 2015; 29:961-70. [PMID: 25990558 DOI: 10.1177/0269881115587143] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
3,4-methylenedioxy-N-methylamphetamine (MDMA) produces diverse pro-social effects. Cognitive training methods rooted in Eastern contemplative practices also produce these effects through the development of a compassionate mindset. Given this similarity, we propose that one potential mechanism of action of MDMA in psychotherapy is through enhancing effects on intrapersonal attitudes (i.e. pro-social attitudes towards the self). We provide a preliminary test of this idea. Recreational MDMA (ecstasy) users were tested on two occasions, having consumed or not consumed ecstasy. Self-critical and self-compassionate responses to self-threatening scenarios were assessed before (T1) and after (T2) ecstasy use (or non-use), and then after compassionate imagery (T3). Moderating roles of dispositional self-criticism and avoidant attachment were examined. Separately, compassionate imagery and ecstasy produced similar sociotropic effects, as well as increases in self-compassion and reductions in self-criticism. Higher attachment-related avoidance was associated with additive effects of compassionate imagery and ecstasy on self-compassion. Findings were in line with MDMA's neuropharmacological profile, its phenomenological effects and its proposed adjunctive use in psychotherapy. However, although conditions were balanced, the experiment was non-blind and MDMA dose/purity was not determined. Controlled studies with pharmaceutically pure MDMA are still needed to test these effects rigorously.
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Affiliation(s)
- Sunjeev K Kamboj
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Emma J Kilford
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Stephanie Minchin
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Abigail Moss
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Will Lawn
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Ravi K Das
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Caroline J Falconer
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Paul Gilbert
- Mental Health Research Unit, University of Derby, Derby, UK
| | - H Valerie Curran
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
| | - Tom P Freeman
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
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Beadman M, Das RK, Freeman TP, Scragg P, West R, Kamboj SK. A comparison of emotion regulation strategies in response to craving cognitions: Effects on smoking behaviour, craving and affect in dependent smokers. Behav Res Ther 2015; 69:29-39. [DOI: 10.1016/j.brat.2015.03.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 03/26/2015] [Accepted: 03/30/2015] [Indexed: 10/23/2022]
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Kamboj SK, Krol KM, Curran HV. A specific association between facial disgust recognition and estradiol levels in naturally cycling women. PLoS One 2015; 10:e0122311. [PMID: 25874795 PMCID: PMC4398500 DOI: 10.1371/journal.pone.0122311] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 02/19/2015] [Indexed: 11/23/2022] Open
Abstract
Subtle changes in social cognition are associated with naturalistic fluctuations in estrogens and progesterone over the course of the menstrual cycle. Using a dynamic emotion recognition task we aimed to provide a comprehensive description of the association between ovarian hormone levels and emotion recognition performance using a variety of performance metrics. Naturally cycling, psychiatrically healthy women attended a single experimental session during a follicular (days 7–13; n = 16), early luteal (days 15–19; n = 14) or late luteal phase (days 22–27; n = 14) of their menstrual cycle. Correct responses and reaction times to dynamic facial expressions were recorded and a two-high threshold analysis was used to assess discrimination and response bias. Salivary progesterone and estradiol were assayed and subjective measures of premenstrual symptoms, anxiety and positive and negative affect assessed. There was no interaction between cycle phase (follicular, early luteal, late luteal) and facial expression (sad, happy, fearful, angry, neutral and disgusted) on any of the recognition performance metrics. However, across the sample as a whole, progesterone levels were positively correlated with reaction times to a variety of facial expressions (anger, happiness, sadness and neutral expressions). In contrast, estradiol levels were specifically correlated with disgust processing on three performance indices (correct responses, response bias and discrimination). Premenstrual symptoms, anxiety and positive and negative affect were not associated with emotion recognition indices or hormone levels. The study highlights the role of naturalistic variations in ovarian hormone levels in modulating emotion recognition. In particular, progesterone seems to have a general slowing effect on facial expression processing. Our findings also provide the first behavioural evidence of a specific role for estrogens in the processing of disgust in humans.
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Affiliation(s)
- Sunjeev K. Kamboj
- Research Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
- * E-mail:
| | - Kathleen M. Krol
- Research Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
| | - H. Valerie Curran
- Research Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
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Das RK, Hindocha C, Freeman TP, Lazzarino AI, Curran HV, Kamboj SK. Assessing the translational feasibility of pharmacological drug memory reconsolidation blockade with memantine in quitting smokers. Psychopharmacology (Berl) 2015; 232:3363-74. [PMID: 26093656 PMCID: PMC4537501 DOI: 10.1007/s00213-015-3990-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 06/01/2015] [Indexed: 11/28/2022]
Abstract
RATIONALE Preclinical reconsolidation research offers the first realistic opportunity to pharmacologically weaken the maladaptive memory structures that support relapse in drug addicts. N-methyl D-aspartate receptor (NMDAR) antagonism is a highly effective means of blocking drug memory reconsolidation. However, no research using this approach exists in human addicts. OBJECTIVES The objective of this study was to assess the potential and clinical outcomes of blocking the reconsolidation of cue-smoking memories with memantine in quitting smokers. METHODS Fifty-nine dependent and motivated to quit smokers were randomised to one of three groups receiving the following: (1) memantine with or (2) without reactivation of associative cue-smoking memories or (3) reactivation with placebo on their target quit day in a double-blind manner. Participants aimed to abstain from smoking for as long as possible. Levels of smoking and FTND score were assessed prior to intervention and up to a year later. Primary outcome was latency to relapse. Subjective craving measures and attentional bias to smoking cues were assessed in-lab. RESULTS All study groups successfully reduced their smoking up to 3 months. Memantine in combination with smoking memory reactivation did not affect any measure of smoking outcome, reactivity or attention capture to smoking cues. CONCLUSIONS Brief exposure to smoking cues with memantine did not appear to weaken these memory traces. These findings could be due to insufficient reconsolidation blockade by memantine or failure of exposure to smoking stimuli to destabilise smoking memories. Research assessing the treatment potential of reconsolidation blockade in human addicts should focus on identification of tolerable drugs that reliably block reward memory reconsolidation and retrieval procedures that reliably destabilise strongly trained memories.
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Affiliation(s)
- Ravi K Das
- Clinical Psychopharmacology Unit, University College London, 1-19 Torrington Place, London, WC1E 6BT, UK,
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Kamboj SK, Oldfield L, Loewenberger A, Das RK, Bisby J, Brewin CR. Voluntary and involuntary emotional memory following an analogue traumatic stressor: the differential effects of communality in men and women. J Behav Ther Exp Psychiatry 2014; 45:421-6. [PMID: 24929781 DOI: 10.1016/j.jbtep.2014.05.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 05/05/2014] [Accepted: 05/06/2014] [Indexed: 10/25/2022]
Abstract
BACKGROUND Men and women show differences in performance on emotional processing tasks. Sex also interacts with personality traits to affect information processing. Here we examine effects of sex, and two personality traits that are differentially expressed in men and women - instrumentality and communality - on voluntary and involuntary memory for distressing video-footage. METHODS On session one, participants (n = 39 men; 40 women) completed the Bem Sex-Role Inventory, which assesses communal and instrumental traits. After viewing film-footage of death/serious injury, participants recorded daily involuntary memories (intrusions) relating to the footage on an online diary for seven days, returning on day eight for a second session to perform a voluntary memory task relating to the film. RESULTS Communality interacted with sex such that men with higher levels of communality reported more frequent involuntary memories. Alternatively, a communality × sex interaction reflected a tendency for women with high levels of communality to perform more poorly on the voluntary recognition memory task. LIMITATIONS The study involved healthy volunteers with no history of significant psychological disorder. Future research with clinical populations will help to determine the generalizability of the current findings. CONCLUSION Communality has separate effects on voluntary and involuntary emotional memory. We suggest that high levels of communality in men and women may confer vulnerability to the negative effects of stressful events either through the over-encoding of sensory/perceptual-information in men or the reduced encoding of contextualised, verbally-based, voluntarily accessible representations in women.
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Affiliation(s)
- Sunjeev K Kamboj
- Research Department of Clinical, Educational and Health Psychology, University College London, Gower Street, London WC1E 6BT, UK.
| | - Lucy Oldfield
- Research Department of Clinical, Educational and Health Psychology, University College London, Gower Street, London WC1E 6BT, UK
| | - Alana Loewenberger
- Research Department of Clinical, Educational and Health Psychology, University College London, Gower Street, London WC1E 6BT, UK
| | - Ravi K Das
- Research Department of Clinical, Educational and Health Psychology, University College London, Gower Street, London WC1E 6BT, UK
| | - James Bisby
- Research Department of Clinical, Educational and Health Psychology, University College London, Gower Street, London WC1E 6BT, UK
| | - Chris R Brewin
- Research Department of Clinical, Educational and Health Psychology, University College London, Gower Street, London WC1E 6BT, UK
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Freeman TP, Das RK, Kamboj SK, Curran HV. Dopamine, urges to smoke, and the relative salience of drug versus non-drug reward. Soc Cogn Affect Neurosci 2014; 10:85-92. [PMID: 24526184 DOI: 10.1093/scan/nsu026] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
When addicted individuals are exposed to drug-related stimuli, dopamine release is thought to mediate incentive salience attribution, increasing attentional bias, craving and drug seeking. It is unclear whether dopamine acts specifically on drug cues versus other rewards, and if these effects correspond with craving and other forms of cognitive bias. Here, we administered the dopamine D2/D3 agonist pramipexole (0.5 mg) to 16 tobacco smokers in a double-blind placebo-controlled crossover design. Visual fixations on smoking and money images were recorded alongside smoking urges and fluency tasks. Pramipexole attenuated a marked bias in initial orienting towards smoking relative to money but did not alter a maintained attentional bias towards smoking. Pramipexole decreased urges to smoke retrospectively after the task but not on a state scale. Fewer smoking words were generated after pramipexole but phonological and semantic fluency were preserved. Although these treatment effects did not correlate with each other, changes in initial orienting towards smoking and money were inversely related to baseline scores. In conclusion, pramipexole can reduce the salience of an addictive drug compared with other rewards and elicit corresponding changes in smoking urges and cognitive bias. These reward-specific and baseline-dependent effects support an 'inverted-U' shaped profile of dopamine in addiction.
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Affiliation(s)
- Tom P Freeman
- Clinical Psychopharmacology Unit, University College London, Gower St, London WC1E 6BT, United Kingdom
| | - Ravi K Das
- Clinical Psychopharmacology Unit, University College London, Gower St, London WC1E 6BT, United Kingdom
| | - Sunjeev K Kamboj
- Clinical Psychopharmacology Unit, University College London, Gower St, London WC1E 6BT, United Kingdom
| | - H Valerie Curran
- Clinical Psychopharmacology Unit, University College London, Gower St, London WC1E 6BT, United Kingdom
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Pajak R, Kamboj SK. Experimental single-session imagery rescripting of distressing memories in bowel/bladder-control anxiety: a case series. Front Psychiatry 2014; 5:182. [PMID: 25566101 PMCID: PMC4265982 DOI: 10.3389/fpsyt.2014.00182] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 12/02/2014] [Indexed: 11/16/2022] Open
Abstract
Bowel and bladder obsession [bowel/bladder-control anxiety (BBCA)] is a viscerally centered phobic syndrome involving a specific concern about losing control of bowel or bladder functioning in a public place. Like other anxiety disorders, BBCA is characterized by intrusive imagery. We have previously described the nature of intrusive mental imagery in BBCA and found imagery themes to be linked to actual experiences of loss of control or to "near misses." A causal role for imagery in symptom maintenance can be inferred by examining the effects of imagery rescripting. Moreover, successful rescripting may point to a potentially efficacious avenue for treatment development. Three cases of imagery rescripting are described here with pre-, post-, and follow-up (1-week) data reported. After rescripting, two participants experienced pronounced reductions in imagery vividness, distress, shame, disgust, and belief conviction. Most importantly, all three participants experienced a reduction in fear-associated bladder and/or bowel sensations. The results support a causal role for mental imagery in bowel-bladder-control anxiety and suggest that rescripting of distressing intrusive memories linked to recurrent images may be a useful avenue for development of cognitive-behavioral treatments of bladder/bowel-control anxiety.
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Affiliation(s)
- Rosanna Pajak
- Research Department of Clinical, Educational and Health Psychology, University College London , London , UK
| | - Sunjeev K Kamboj
- Research Department of Clinical, Educational and Health Psychology, University College London , London , UK
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Morgan CJA, Das RK, Joye A, Curran HV, Kamboj SK. Cannabidiol reduces cigarette consumption in tobacco smokers: preliminary findings. Addict Behav 2013; 38:2433-6. [PMID: 23685330 DOI: 10.1016/j.addbeh.2013.03.011] [Citation(s) in RCA: 118] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Revised: 01/29/2013] [Accepted: 03/25/2013] [Indexed: 11/19/2022]
Abstract
The role of the endocannabinoid system in nicotine addiction is being increasingly acknowledged. We conducted a pilot, randomised double blind placebo controlled study set out to assess the impact of the ad-hoc use of cannabidiol (CBD) in smokers who wished to stop smoking. 24 smokers were randomised to receive an inhaler of CBD (n=12) or placebo (n=12) for one week, they were instructed to use the inhaler when they felt the urge to smoke. Over the treatment week, placebo treated smokers showed no differences in number of cigarettes smoked. In contrast, those treated with CBD significantly reduced the number of cigarettes smoked by ~40% during treatment. Results also indicated some maintenance of this effect at follow-up. These preliminary data, combined with the strong preclinical rationale for use of this compound, suggest CBD to be a potential treatment for nicotine addiction that warrants further exploration.
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Affiliation(s)
- Celia J A Morgan
- Clinical Psychopharmacology Unit, University College London, London, UK.
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Pajak R, Lackner J, Kamboj SK. A systematic review of minimal-contact psychological treatments for symptom management in irritable bowel syndrome. J Psychosom Res 2013; 75:103-12. [PMID: 23915765 DOI: 10.1016/j.jpsychores.2013.05.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 05/13/2013] [Accepted: 05/14/2013] [Indexed: 12/19/2022]
Abstract
OBJECTIVE Psychological treatments are effective in alleviating symptoms of IBS but are not widely available. The need for wider dissemination of treatments has encouraged the development of 'minimal-contact' therapies requiring fewer resources than existing psychological treatments which rely on face-to-face contact. METHOD Using comprehensive search terms, the Embase, Medline and PsychInfo databases (all years) were searched. RESULTS Twelve studies--nine RCTs and three non-controlled preliminary studies - meeting inclusion criteria were reviewed and assessed for quality using objective criteria. Apart from one study of expressive writing, all interventions were based on cognitive (and/or) behavioural principles or hypnosis and tended to be adaptations of existing therapist-led interventions. Compared to control conditions, minimal-contact interventions were efficacious, the majority of studies showing statistically significant improvements by the end of treatment. For cognitive-behaviour-therapy-based interventions effects sizes were large. The two studies that compared minimal-contact with therapist-delivered interventions broadly suggest comparable outcomes between these modalities. CONCLUSIONS Minimal-contact cognitive-behavioural interventions show promise in the treatment of IBS. Because of the lower quality of studies of hypnosis and those involving interventions delivered entirely remotely, further support is needed before such approaches can be recommended for widespread use. More generally, future research should use representative samples, active control conditions, and intention to treat analysis. Nonetheless, existing high quality studies suggest that minimal-contact therapies may be a safe, effective means of achieving scaleability of psychological treatments for IBS.
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Affiliation(s)
- Rosanna Pajak
- Research Department of Clinical, Educational and Health Psychology, University College London, London, UK
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Soni M, Curran VH, Kamboj SK. Identification of a narrow post-ovulatory window of vulnerability to distressing involuntary memories in healthy women. Neurobiol Learn Mem 2013; 104:32-8. [PMID: 23611942 DOI: 10.1016/j.nlm.2013.04.003] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 04/05/2013] [Indexed: 10/26/2022]
Abstract
Psychological disorders characterised by intrusive memories are more prevalent in women than men. The biological, social and cognitive processes underlying this gender-difference have yet to be fully elucidated. Some evidence suggests that (fluctuations in) ovarian hormone levels are responsible for altered sensitivity to emotional stimuli during certain phases in the menstrual-cycle and this may form the basis of a specific vulnerability to psychological disorders in women. The post-ovulatory (luteal) phase has been identified as a period of particular vulnerability to the development of post-traumatic stress disorder (PTSD). Using an experimental model of PTSD, we examine whether differences are detectable between discrete phases in the menstrual-cycle in the experience of intrusive memories. Women (18-35 years-old) in one of three tightly-defined periods within the menstrual cycle--mid-follicular (n=15), early-luteal (n=15) and late-luteal (n=11)--provided saliva samples for ovarian-hormone assay and watched a distressing film. Subsequent intrusive memories, assessed using a daily online-diary, occurred significantly more frequently in the early-luteal group compared to mid-follicular and late-luteal groups. Intrusion frequency was negatively correlated with the estradiol-to-progesterone ratio, but not estradiol or progesterone alone, suggesting that the interactive effect of low estradiol and high progesterone at encoding contributes to the observed effect. Our results support the need for further research in a clinical context with naturally-cycling women who experience a traumatic event, since assessment of days-since-last-menses and ovarian hormone levels may help to identify those at greatest risk of developing re-experiencing symptoms akin to those seen in psychological disorder such as depression and PTSD.
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Affiliation(s)
- Mira Soni
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, Gower Street, London WC1E 6BT, UK
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Das RK, Kamboj SK. Maintaining clinical relevance: considerations for the future of research into D-cycloserine and cue exposure therapy for addiction. Biol Psychiatry 2012; 72:e29-30; author reply e31-2. [PMID: 22748617 DOI: 10.1016/j.biopsych.2012.05.030] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 05/28/2012] [Accepted: 05/30/2012] [Indexed: 10/28/2022]
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Abstract
BACKGROUND Emotional dysfunction is a core feature of psychotic disorders. One expression of such dysfunction is a reduction of the emotion-induced enhancement of memory which is normally found in healthy individuals. Less severe disruption of emotional processing may also be present in individuals prone to 'unusual' psychosis-like experiences. In this study we investigate voluntary declarative (i.e. explicit or episodic) emotional memory performance, primarily in relation to positive schizotypy (as measured by the unusual experiences scale of the O-LIFE). The effect of negative schizotypy (introvertive anhedonia scale of the O-LIFE) was also explored. We hypothesized that schizotypal individuals (scoring highly on Unusual Experiences) would show reduced memory enhancement. METHODS One hundred and two healthy participants viewed a narrated slide-show containing neutral and negative emotional content. They rated the story on a number of affective dimensions and completed a variety of trait measures, including a multi-dimensional measure of schizotypy. Seven days later, a memory test was performed and frequency of involuntary memories related to the slide-show assessed. RESULTS The voluntary declarative emotional memory advantage in recall seen in low scorers (25%ile) on unusual experiences was absent in high scorers (75%ile), despite greater subjective fearfulness and emotionality in that group. However, the high scoring group did report experiencing more involuntary memories related to the story. There was no effect of negative schizotypy on declarative emotional memory. CONCLUSIONS The emotional memory difficulties seen in studies of schizophrenia may extend to those with a vulnerability to positive psychosis-like experiences. This vulnerability may be expressed in both voluntary declarative - as well as involuntary - emotional memory performance.
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Affiliation(s)
- Rosa Hoshi
- Research Department of Clinical Educational and Health Psychology, University College London, Gower Street, London, WC1E 6BT, UK
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Kamboj SK, Massey-Chase R, Rodney L, Das R, Almahdi B, Curran HV, Morgan CJA. Changes in cue reactivity and attentional bias following experimental cue exposure and response prevention: a laboratory study of the effects of D-cycloserine in heavy drinkers. Psychopharmacology (Berl) 2011; 217:25-37. [PMID: 21455709 DOI: 10.1007/s00213-011-2254-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2010] [Accepted: 03/01/2011] [Indexed: 11/28/2022]
Abstract
RATIONALE The effects of D-cycloserine (DCS) in animal models of anxiety disorders and addiction indicate a role for N-methyl D-aspartate (NMDA) receptors in extinction learning. Exposure/response prevention treatments for anxiety disorders in humans are enhanced by DCS, suggesting a promising co-therapy regime, mediated by NMDA receptors. Exposure/response prevention may also be effective in problematic drinkers, and DCS might enhance habituation to cues in these individuals. Since heavy drinkers show ostensible conditioned responses to alcohol cues, habituation following exposure/response prevention should be evident in these drinkers, with DCS enhancing this effect. OBJECTIVES The objective of this study is to investigate the effect of DCS on exposure/response prevention in heavy drinkers. METHODS In a randomised, double-blind, placebo-controlled study, heavy social drinkers recruited from the community received either DCS (125 mg; n = 19) or placebo (n = 17) 1 h prior to each of two sessions of exposure/response prevention. Cue reactivity and attentional bias were assessed during these two sessions and at a third follow-up session. Between-session drinking behaviour was recorded. RESULTS Robust cue reactivity and attentional bias to alcohol cues was evident, as expected of heavy drinkers. Within- and between-session habituation of cue reactivity, as well as a reduction in attentional bias to alcohol cues over time was found. However, there was no evidence of greater habituation in the DCS group. Subtle stimulant effects (increased subjective contentedness and euphoria) which were unrelated to exposure/response prevention were found following DCS. CONCLUSIONS DCS does not appear to enhance habituation of alcohol cue reactivity in heavy non-dependent drinkers. Its utility in enhancing treatments based on exposure/response prevention in dependent drinkers or drug users remains open.
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Affiliation(s)
- Sunjeev K Kamboj
- Clinical Psychopharmacology Unit, Research Department of Clinical, Educational and Health Psychology, University College London, Gower Street, London WC1E6BT, UK.
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Carroll EMA, Kamboj SK, Conroy L, Tookman A, Williams ACDC, Jones L, Morgan CJA, Curran HV. Facial affect processing in patients receiving opioid treatment in palliative care: preferential processing of threat in pain catastrophizers. J Pain Symptom Manage 2011; 41:975-85. [PMID: 21251795 DOI: 10.1016/j.jpainsymman.2010.08.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Revised: 08/28/2010] [Accepted: 09/03/2010] [Indexed: 11/20/2022]
Abstract
CONTEXT As a multidimensional phenomenon, pain is influenced by various psychological factors. One such factor is catastrophizing, which is associated with higher pain intensity and emotional distress in cancer and noncancer pain. One possibility is that catastrophizing represents a general cognitive style that preferentially supports the processing of negative affective stimuli. Such preferential processing of threat--toward negative facial expressions, for example--is seen in emotional disorders and is sensitive to pharmacological treatment. Whether pharmacological (analgesic) treatment might also influence the processing of threat in pain patients is currently unclear. OBJECTIVES This study investigates the effects catastrophizing on processing of facial affect in those receiving an acute opioid dose. METHODS In a double-blind crossover design, the performance of 20 palliative care patients after their usual dose of immediate-release opioid was compared with their performance following matched-placebo administration on a facial affect recognition (i.e., speed and accuracy) and threat-pain estimation task (i.e., ratings of pain intensity). The influence of catastrophizing was examined by splitting the sample according to their score on the Pain Catastrophizing Scale (PCS). RESULTS Opioid administration had no effect on facial affect processing compared with placebo. However, the main finding was that enhanced processing of fear, sadness, and disgust was found only in patients who scored highly on the PCS. There was no difference in performance between the two PCS groups on the other emotions (i.e., happiness, surprise, and anger). CONCLUSION These findings suggest that catastrophizing is associated with an affective information-processing bias in patients with severe pain conditions.
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Affiliation(s)
- Erin M A Carroll
- Research Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
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Winfield H, Kamboj SK. Schizotypy and mental time travel. Conscious Cogn 2010; 19:321-7. [DOI: 10.1016/j.concog.2009.11.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2009] [Revised: 11/25/2009] [Accepted: 11/28/2009] [Indexed: 11/25/2022]
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