1
|
Norbury A, Seeley SH, Perez-Rodriguez MM, Feder A. Functional neuroimaging of resilience to trauma: convergent evidence and challenges for future research. Psychol Med 2023; 53:3293-3305. [PMID: 37264949 DOI: 10.1017/s0033291723001162] [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] [Indexed: 06/03/2023]
Abstract
Resilience is broadly defined as the ability to adapt successfully following stressful life events. Here, we review functional MRI studies that investigated key psychological factors that have been consistently linked to resilience to severe adversity and trauma exposure. These domains include emotion regulation (including cognitive reappraisal), reward responsivity, and cognitive control. Further, we briefly review functional imaging evidence related to emerging areas of study that may potentially facilitate resilience: namely social cognition, active coping, and successful fear extinction. Finally, we also touch upon ongoing issues in neuroimaging study design that will need to be addressed to enable us to harness insight from such studies to improve treatments for - or, ideally, guard against the development of - debilitating post-traumatic stress syndromes.
Collapse
Affiliation(s)
- Agnes Norbury
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Queen Square Institute of Neurology and Mental Health Neuroscience Department, Applied Computational Psychiatry Lab, Max Planck Centre for Computational Psychiatry and Ageing Research, University College London, London, UK
| | - Saren H Seeley
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | - Adriana Feder
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| |
Collapse
|
2
|
Norbury A, Rutter SB, Collins AB, Costi S, Jha MK, Horn SR, Kautz M, Corniquel M, Collins KA, Glasgow AM, Brallier J, Shin LM, Charney DS, Murrough JW, Feder A. Neuroimaging correlates and predictors of response to repeated-dose intravenous ketamine in PTSD: preliminary evidence. Neuropsychopharmacology 2021; 46:2266-2277. [PMID: 34333555 PMCID: PMC8580962 DOI: 10.1038/s41386-021-01104-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 06/15/2021] [Accepted: 07/07/2021] [Indexed: 02/06/2023]
Abstract
Promising initial data indicate that the glutamate N-methyl-D-aspartate (NMDA) receptor antagonist ketamine may be beneficial in post-traumatic stress disorder (PTSD). Here, we explore the neural correlates of ketamine-related changes in PTSD symptoms, using a rich battery of functional imaging data (two emotion-processing tasks and one task-free scan), collected from a subset of participants of a randomized clinical trial of repeated-dose intravenous ketamine vs midazolam (total N = 21). In a pre-registered analysis, we tested whether changes in an a priori set of imaging measures from a target neural circuit were predictive of improvement in PTSD symptoms, using leave-one-out cross-validated elastic-net regression models (regions of interest in the target circuit consisted of the dorsal and rostral anterior cingulate cortex, ventromedial prefrontal cortex, anterior hippocampus, anterior insula, and amygdala). Improvements in PTSD severity were associated with increased functional connectivity between the ventromedial prefrontal cortex (vmPFC) and amygdala during emotional face-viewing (change score retained in model with minimum predictive error in left-out subjects, standardized regression coefficient [β] = 2.90). This effect was stronger in participants who received ketamine compared to midazolam (interaction β = 0.86), and persisted following inclusion of concomitant change in depressive symptoms in the analysis model (β = 0.69). Improvement following ketamine was also predicted by decreased dorsal anterior cingulate activity during emotional conflict regulation, and increased task-free connectivity between the vmPFC and anterior insula (βs = -2.82, 0.60). Exploratory follow-up analysis via dynamic causal modelling revealed that whilst improvement in PTSD symptoms following either drug was associated with decreased excitatory modulation of amygdala→vmPFC connectivity during emotional face-viewing, increased top-down inhibition of the amygdala by the vmPFC was only observed in participants who improved under ketamine. Individuals with low prefrontal inhibition of amygdala responses to faces at baseline also showed greater improvements following ketamine treatment. These preliminary findings suggest that, specifically under ketamine, improvements in PTSD symptoms are accompanied by normalization of hypofrontal control over amygdala responses to social signals of threat.
Collapse
Affiliation(s)
- Agnes Norbury
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Sarah B Rutter
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Abigail B Collins
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Sara Costi
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Manish K Jha
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Sarah R Horn
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Marin Kautz
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Morgan Corniquel
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Katherine A Collins
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, USA
| | - Andrew M Glasgow
- Department of Anesthesiology, Perioperative and Pain Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Jess Brallier
- Department of Anesthesiology, Perioperative and Pain Medicine, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Lisa M Shin
- Department of Psychology, Tufts University, Medford, MA, USA
- Department of Psychiatry, Massachusetts General Hospital/Harvard Medical School, Boston, MA, USA
| | - Dennis S Charney
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - James W Murrough
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Adriana Feder
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| |
Collapse
|
3
|
Ryu J, Sükei E, Norbury A, H Liu S, Campaña-Montes JJ, Baca-Garcia E, Artés A, Perez-Rodriguez MM. Shift in Social Media App Usage During COVID-19 Lockdown and Clinical Anxiety Symptoms: Machine Learning-Based Ecological Momentary Assessment Study. JMIR Ment Health 2021; 8:e30833. [PMID: 34524091 PMCID: PMC8448085 DOI: 10.2196/30833] [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] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 07/22/2021] [Accepted: 07/29/2021] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Anxiety symptoms during public health crises are associated with adverse psychiatric outcomes and impaired health decision-making. The interaction between real-time social media use patterns and clinical anxiety during infectious disease outbreaks is underexplored. OBJECTIVE We aimed to evaluate the usage pattern of 2 types of social media apps (communication and social networking) among patients in outpatient psychiatric treatment during the COVID-19 surge and lockdown in Madrid, Spain and their short-term anxiety symptoms (7-item General Anxiety Disorder scale) at clinical follow-up. METHODS The individual-level shifts in median social media usage behavior from February 1 through May 3, 2020 were summarized using repeated measures analysis of variance that accounted for the fixed effects of the lockdown (prelockdown versus postlockdown), group (clinical anxiety group versus nonclinical anxiety group), the interaction of lockdown and group, and random effects of users. A machine learning-based approach that combined a hidden Markov model and logistic regression was applied to predict clinical anxiety (n=44) and nonclinical anxiety (n=51), based on longitudinal time-series data that comprised communication and social networking app usage (in seconds) as well as anxiety-associated clinical survey variables, including the presence of an essential worker in the household, worries about life instability, changes in social interaction frequency during the lockdown, cohabitation status, and health status. RESULTS Individual-level analysis of daily social media usage showed that the increase in communication app usage from prelockdown to lockdown period was significantly smaller in the clinical anxiety group than that in the nonclinical anxiety group (F1,72=3.84, P=.05). The machine learning model achieved a mean accuracy of 62.30% (SD 16%) and area under the receiver operating curve 0.70 (SD 0.19) in 10-fold cross-validation in identifying the clinical anxiety group. CONCLUSIONS Patients who reported severe anxiety symptoms were less active in communication apps after the mandated lockdown and more engaged in social networking apps in the overall period, which suggested that there was a different pattern of digital social behavior for adapting to the crisis. Predictive modeling using digital biomarkers-passive-sensing of shifts in category-based social media app usage during the lockdown-can identify individuals at risk for psychiatric sequelae.
Collapse
Affiliation(s)
- Jihan Ryu
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Emese Sükei
- Department of Signal Theory and Communications, Universidad Carlos III de Madrid, Madrid, Spain
| | - Agnes Norbury
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Shelley H Liu
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | | | - Enrique Baca-Garcia
- Evidence Based Behavior, Madrid, Spain.,Department of Psychiatry, University Hospital Jimenez Diaz Foundation, Madrid, Spain
| | - Antonio Artés
- Department of Signal Theory and Communications, Universidad Carlos III de Madrid, Madrid, Spain.,Evidence Based Behavior, Madrid, Spain.,Gregorio Marañón Health Research Institute, Madrid, Spain
| | | |
Collapse
|
4
|
Sükei E, Norbury A, Perez-Rodriguez MM, Olmos PM, Artés A. Predicting Emotional States Using Behavioral Markers Derived From Passively Sensed Data: Data-Driven Machine Learning Approach. JMIR Mhealth Uhealth 2021; 9:e24465. [PMID: 33749612 PMCID: PMC8088855 DOI: 10.2196/24465] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 01/29/2021] [Accepted: 02/15/2021] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Mental health disorders affect multiple aspects of patients' lives, including mood, cognition, and behavior. eHealth and mobile health (mHealth) technologies enable rich sets of information to be collected noninvasively, representing a promising opportunity to construct behavioral markers of mental health. Combining such data with self-reported information about psychological symptoms may provide a more comprehensive and contextualized view of a patient's mental state than questionnaire data alone. However, mobile sensed data are usually noisy and incomplete, with significant amounts of missing observations. Therefore, recognizing the clinical potential of mHealth tools depends critically on developing methods to cope with such data issues. OBJECTIVE This study aims to present a machine learning-based approach for emotional state prediction that uses passively collected data from mobile phones and wearable devices and self-reported emotions. The proposed methods must cope with high-dimensional and heterogeneous time-series data with a large percentage of missing observations. METHODS Passively sensed behavior and self-reported emotional state data from a cohort of 943 individuals (outpatients recruited from community clinics) were available for analysis. All patients had at least 30 days' worth of naturally occurring behavior observations, including information about physical activity, geolocation, sleep, and smartphone app use. These regularly sampled but frequently missing and heterogeneous time series were analyzed with the following probabilistic latent variable models for data averaging and feature extraction: mixture model (MM) and hidden Markov model (HMM). The extracted features were then combined with a classifier to predict emotional state. A variety of classical machine learning methods and recurrent neural networks were compared. Finally, a personalized Bayesian model was proposed to improve performance by considering the individual differences in the data and applying a different classifier bias term for each patient. RESULTS Probabilistic generative models proved to be good preprocessing and feature extractor tools for data with large percentages of missing observations. Models that took into account the posterior probabilities of the MM and HMM latent states outperformed those that did not by more than 20%, suggesting that the underlying behavioral patterns identified were meaningful for individuals' overall emotional state. The best performing generalized models achieved a 0.81 area under the curve of the receiver operating characteristic and 0.71 area under the precision-recall curve when predicting self-reported emotional valence from behavior in held-out test data. Moreover, the proposed personalized models demonstrated that accounting for individual differences through a simple hierarchical model can substantially improve emotional state prediction performance without relying on previous days' data. CONCLUSIONS These findings demonstrate the feasibility of designing machine learning models for predicting emotional states from mobile sensing data capable of dealing with heterogeneous data with large numbers of missing observations. Such models may represent valuable tools for clinicians to monitor patients' mood states.
Collapse
Affiliation(s)
- Emese Sükei
- Signal Theory and Communications Department, Universidad Carlos III de Madrid, Leganés, Spain
| | - Agnes Norbury
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | | | - Pablo M Olmos
- Signal Theory and Communications Department, Universidad Carlos III de Madrid, Leganés, Spain
- Gregorio Marañón Health Research Institute, Madrid, Spain
| | - Antonio Artés
- Signal Theory and Communications Department, Universidad Carlos III de Madrid, Leganés, Spain
- Gregorio Marañón Health Research Institute, Madrid, Spain
| |
Collapse
|
5
|
Norbury A, Brinkman H, Kowalchyk M, Monti E, Pietrzak RH, Schiller D, Feder A. Latent cause inference during extinction learning in trauma-exposed individuals with and without PTSD. Psychol Med 2021; 52:1-12. [PMID: 33682653 DOI: 10.1017/s0033291721000647] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Problems in learning that sights, sounds, or situations that were once associated with danger have become safe (extinction learning) may explain why some individuals suffer prolonged psychological distress following traumatic experiences. Although simple learning models have been unable to provide a convincing account of why this learning fails, it has recently been proposed that this may be explained by individual differences in beliefs about the causal structure of the environment. METHODS Here, we tested two competing hypotheses as to how differences in causal inference might be related to trauma-related psychopathology, using extinction learning data collected from clinically well-characterised individuals with varying degrees of post-traumatic stress (N = 56). Model parameters describing individual differences in causal inference were related to multiple post-traumatic stress disorder (PTSD) and depression symptom dimensions via network analysis. RESULTS Individuals with more severe PTSD were more likely to assign observations from conditioning and extinction stages to a single underlying cause. Specifically, greater re-experiencing symptom severity was associated with a lower likelihood of inferring that multiple causes were active in the environment. CONCLUSIONS We interpret these results as providing evidence of a primary deficit in discriminative learning in participants with more severe PTSD. Specifically, a tendency to attribute a greater diversity of stimulus configurations to the same underlying cause resulted in greater uncertainty about stimulus-outcome associations, impeding learning both that certain stimuli were safe, and that certain stimuli were no longer dangerous. In the future, better understanding of the role of causal inference in trauma-related psychopathology may help refine cognitive therapies for these disorders.
Collapse
Affiliation(s)
- Agnes Norbury
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Hannah Brinkman
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Mary Kowalchyk
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Elisa Monti
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Robert H Pietrzak
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- United States Department of Veterans Affairs, National Center for Posttraumatic Stress Disorder, Clinical Neurosciences Division, VA Connecticut Healthcare System, West Haven, CT, USA
| | - Daniela Schiller
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Adriana Feder
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| |
Collapse
|
6
|
Norbury A, Liu SH, Campaña-Montes JJ, Romero-Medrano L, Barrigón ML, Smith E, Artés-Rodríguez A, Baca-García E, Perez-Rodriguez MM. Social media and smartphone app use predicts maintenance of physical activity during Covid-19 enforced isolation in psychiatric outpatients. Mol Psychiatry 2021; 26:3920-3930. [PMID: 33318619 PMCID: PMC7734389 DOI: 10.1038/s41380-020-00963-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [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: 07/13/2020] [Revised: 11/05/2020] [Accepted: 11/16/2020] [Indexed: 02/06/2023]
Abstract
There is growing concern that the social and physical distancing measures implemented in response to the Covid-19 pandemic may negatively impact health in other areas, via both decreased physical activity and increased social isolation. Here, we investigated whether increased engagement with digital social tools may help mitigate effects of enforced isolation on physical activity and mood, in a naturalistic study of at-risk individuals. Passively sensed smartphone app use and actigraphy data were collected from a group of psychiatric outpatients before and during imposition of strict Covid-19 lockdown measures. Data were analysed using Gaussian graphical models: a form of network analysis which gives insight into the predictive relationships between measures across timepoints. Within-individuals, we found evidence of a positive predictive path between digital social engagement, general smartphone use, and physical activity-selectively under lockdown conditions (N = 127 individual users, M = 6201 daily observations). Further, we observed a positive relationship between social media use and total daily steps across individuals during (but not prior to) lockdown. Although there are important limitations on the validity of drawing causal conclusions from observational data, a plausible explanation for our findings is that, during lockdown, individuals use their smartphones to access social support, which may help guard against negative effects of in-person social deprivation and other pandemic-related stress. Importantly, passive monitoring of smartphone app usage is low burden and non-intrusive. Given appropriate consent, this could help identify people who are failing to engage in usual patterns of digital social interaction, providing a route to early intervention.
Collapse
Affiliation(s)
- Agnes Norbury
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
| | - Shelley H. Liu
- grid.59734.3c0000 0001 0670 2351Department of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai, New York, NY USA
| | - Juan José Campaña-Montes
- Evidence-Based Behavior, Madrid, Spain ,grid.7840.b0000 0001 2168 9183Department of Signal Theory and Communications, Universidad Carlos III de Madrid, Madrid, Spain
| | - Lorena Romero-Medrano
- Evidence-Based Behavior, Madrid, Spain ,grid.7840.b0000 0001 2168 9183Department of Signal Theory and Communications, Universidad Carlos III de Madrid, Madrid, Spain
| | - María Luisa Barrigón
- grid.419651.e0000 0000 9538 1950Department of Psychiatry, University Hospital Jimenez Diaz Foundation, Madrid, Spain
| | - Emma Smith
- grid.59734.3c0000 0001 0670 2351Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY USA
| | | | - Antonio Artés-Rodríguez
- Evidence-Based Behavior, Madrid, Spain ,grid.7840.b0000 0001 2168 9183Department of Signal Theory and Communications, Universidad Carlos III de Madrid, Madrid, Spain ,Instituto de Investigaciones Sanitarias Gregorio Marañón, Madrid, Spain ,grid.469673.90000 0004 5901 7501CIBERSAM, Carlos III Institute of Health, Madrid, Spain
| | - Enrique Baca-García
- grid.419651.e0000 0000 9538 1950Department of Psychiatry, University Hospital Jimenez Diaz Foundation, Madrid, Spain ,grid.5515.40000000119578126Department of Psychiatry, Madrid Autonomous University, Madrid, Spain ,grid.459654.fDepartment of Psychiatry, University Hospital Rey Juan Carlos, Mostoles, Spain ,Department of Psychiatry, General Hospital of Villalba, Madrid, Spain ,grid.411171.30000 0004 0425 3881Department of Psychiatry, University Hospital Infanta Elena, Valdemoro, Spain ,grid.5515.40000000119578126Department of Psychiatry, Madrid Autonomous University, Madrid, Spain ,grid.411964.f0000 0001 2224 0804Universidad Catolica del Maule, Talca, Chile ,grid.411165.60000 0004 0593 8241Department of Psychiatry, Centre Hospitalier Universitaire de Nîmes, Nîmes, France
| | - M. Mercedes Perez-Rodriguez
- grid.59734.3c0000 0001 0670 2351Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY USA
| |
Collapse
|
7
|
Morris LS, Norbury A, Smith DA, Harrison NA, Voon V, Murrough JW. Dissociating self-generated volition from externally-generated motivation. PLoS One 2020; 15:e0232949. [PMID: 32428020 PMCID: PMC7236980 DOI: 10.1371/journal.pone.0232949] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [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: 11/05/2019] [Accepted: 04/24/2020] [Indexed: 12/21/2022] Open
Abstract
Insight into motivational processes may be gained by examining measures of willingness to exert effort for rewards, which have been linked to neuropsychiatric symptoms of anhedonia and apathy. However, while much work has focused on the development of models of motivation based on classic tasks of externally-generated levels of effort for reward, there has been less focus on the question of self-generated motivation or volition. We developed a task that aims to capture separate measures of self-generated and externally-generated motivation, with two task variants for physical and cognitive effort, and sought to test and validate this measure in two populations of healthy volunteers (N = 27 and N = 28). Similar to previous reports, a sigmoid function represented a better overall fit to the effort-reward data than a linear or Weibull model. Individual sigmoid function shapes were governed by two free parameters: bias (the amount of reward needed for effort initiation) and reward insensitivity (the amount of increase in reward needed to accelerate effort expenditure). For both physical and cognitive effort, bias was higher in the self-generated condition, indicating reduced self-generated volitional effort initiation, compared to externally-generated effort initiation, across effort domains. Bias against initial effort initiation in the self-generated condition was related to a specific dimensional measure of anticipatory anhedonia. For physical effort only, reward insensitivity was also higher in the self-generated condition compared to the externally-generated motivation condition, indicating lower self-generated effort acceleration. This work provides a novel objective measure of self-generated motivation that may provide insights into mechanisms of anhedonia and related symptoms.
Collapse
Affiliation(s)
- Laurel S. Morris
- Department of Psychiatry, Depression and Anxiety Center for Discovery and Treatment, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Agnes Norbury
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Derek A. Smith
- Department of Radiology, BioMedical Engineering and Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Neil A. Harrison
- Division of Psychological Medicine and Clinical Neuroscience, Cardiff University, Cardiff, United Kingdom
- Department of Neuroscience, Brighton and Sussex Medical School, University of Sussex, Brighton, United Kingdom
| | - Valerie Voon
- Department of Psychiatry, University of Cambridge, Addenbrooke’s Hospital, Cambridge, United Kingdom
| | - James W. Murrough
- Department of Psychiatry, Depression and Anxiety Center for Discovery and Treatment, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| |
Collapse
|
8
|
Abstract
Response rates to available treatments for psychological and chronic pain disorders are poor, and there is a considerable burden of suffering and disability for patients, who often cycle through several rounds of ineffective treatment. As individuals presenting to the clinic with symptoms of these disorders are likely to be heterogeneous, there is considerable interest in the possibility that different constellations of signs could be used to identify subgroups of patients that might preferentially benefit from particular kinds of treatment. To this end, there has been a recent focus on the application of machine learning methods to attempt to identify sets of predictor variables (demographic, genetic, etc.) that could be used to target individuals towards treatments that are more likely to work for them in the first instance. Importantly, the training of such models generally relies on datasets where groups of individual predictor variables are labelled with a binary outcome category - usually 'responder' or 'non-responder' (to a particular treatment). However, as previously highlighted in other areas of medicine, there is a basic statistical problem in classifying individuals as 'responding' to a particular treatment on the basis of data from conventional randomized controlled trials. Specifically, insufficient information on the partition of variance components in individual symptom changes mean that it is inappropriate to consider data from the active treatment arm alone in this way. This may be particularly problematic in the case of psychiatric and chronic pain symptom data, where both within-subject variability and measurement error are likely to be high. Here, we outline some possible solutions to this problem in terms of dataset design and machine learning methodology, and conclude that it is important to carefully consider the kind of inferences that particular training data are able to afford, especially in arenas where the potential clinical benefit is so large.
Collapse
Affiliation(s)
- Agnes Norbury
- Computational and Biological Learning Laboratory, Department of Engineering, University of Cambridge, Cambridge, CB2 1PZ, UK
| | - Ben Seymour
- Computational and Biological Learning Laboratory, Department of Engineering, University of Cambridge, Cambridge, CB2 1PZ, UK
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, Osaka, 565-0871, Japan
| |
Collapse
|
9
|
Abstract
Response rates to available treatments for psychological and chronic pain disorders are poor, and there is a substantial burden of suffering and disability for patients, who often cycle through several rounds of ineffective treatment. As individuals presenting to the clinic with symptoms of these disorders are likely to be heterogeneous, there is considerable interest in the possibility that different constellations of signs could be used to identify subgroups of patients that might preferentially benefit from particular kinds of treatment. To this end, there has been a recent focus on the application of machine learning methods to attempt to identify sets of predictor variables (demographic, genetic, etc.) that could be used to target individuals towards treatments that are more likely to work for them in the first instance. Importantly, the training of such models generally relies on datasets where groups of individual predictor variables are labelled with a binary outcome category - usually 'responder' or 'non-responder' (to a particular treatment). However, as previously highlighted in other areas of medicine, there is a basic statistical problem in classifying individuals as 'responding' to a particular treatment on the basis of data from conventional randomized controlled trials. Specifically, insufficient information on the partition of variance components in individual symptom changes mean that it is inappropriate to consider data from the active treatment arm alone in this way. This may be particularly problematic in the case of psychiatric and chronic pain symptom data, where both within-subject variability and measurement error are likely to be high. Here, we outline some possible solutions to this problem in terms of dataset design and machine learning methodology, and conclude that it is important to carefully consider the kind of inferences that particular training data are able to afford, especially in arenas where the potential clinical benefit is so large.
Collapse
Affiliation(s)
- Agnes Norbury
- Computational and Biological Learning Laboratory, Department of Engineering, University of Cambridge, Cambridge, CB2 1PZ, UK
| | - Ben Seymour
- Computational and Biological Learning Laboratory, Department of Engineering, University of Cambridge, Cambridge, CB2 1PZ, UK
- Center for Information and Neural Networks, National Institute of Information and Communications Technology, Osaka, 565-0871, Japan
| |
Collapse
|
10
|
Abstract
Generalization during aversive decision-making allows us to avoid a broad range of potential threats following experience with a limited set of exemplars. However, over-generalization, resulting in excessive and inappropriate avoidance, has been implicated in a variety of psychological disorders. Here, we use reinforcement learning modelling to dissect out different contributions to the generalization of instrumental avoidance in two groups of human volunteers (N = 26, N = 482). We found that generalization of avoidance could be parsed into perceptual and value-based processes, and further, that value-based generalization could be subdivided into that relating to aversive and neutral feedback - with corresponding circuits including primary sensory cortex, anterior insula, amygdala and ventromedial prefrontal cortex. Further, generalization from aversive, but not neutral, feedback was associated with self-reported anxiety and intrusive thoughts. These results reveal a set of distinct mechanisms that mediate generalization in avoidance learning, and show how specific individual differences within them can yield anxiety.
Collapse
Affiliation(s)
- Agnes Norbury
- Computational and Biological Learning Laboratory, Department of EngineeringUniversity of CambridgeCambridgeUnited Kingdom
| | - Trevor W Robbins
- Department of PsychologyUniversity of CambridgeCambridgeUnited Kingdom,Behavioural and Clinical Neuroscience InstituteUniversity of CambridgeCambridgeUnited Kingdom
| | - Ben Seymour
- Computational and Biological Learning Laboratory, Department of EngineeringUniversity of CambridgeCambridgeUnited Kingdom,Center for Information and Neural NetworksNational Institute of Information and Communications TechnologySuita CityJapan
| |
Collapse
|
11
|
Fallon SJ, Zokaei N, Norbury A, Manohar SG, Husain M. Dopamine Alters the Fidelity of Working Memory Representations according to Attentional Demands. J Cogn Neurosci 2016; 29:728-738. [PMID: 27897674 PMCID: PMC5889096 DOI: 10.1162/jocn_a_01073] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [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: 11/17/2022]
Abstract
Capacity limitations in working memory (WM) necessitate the need to
effectively control its contents. Here, we examined the effect of cabergoline, a
dopamine D2 receptor agonist, on WM using a continuous report
paradigm that allowed us to assess the fidelity with which items are stored. We
assessed recall performance under three different gating conditions: remembering
only one item, being cued to remember one target among distractors, and having
to remember all items. Cabergoline had differential effects on recall
performance according to whether distractors had to be ignored and whether
mnemonic resources could be deployed exclusively to the target. Compared with
placebo, cabergoline improved mnemonic performance when there were no
distractors but significantly reduced performance when distractors were
presented in a precue condition. No significant difference in performance was
observed under cabergoline when all items had to be remembered. By applying a
stochastic model of response selection, we established that the causes of
drug-induced changes in performance were due to changes in the precision with
which items were stored in WM. However, there was no change in the extent to
which distractors were mistaken for targets. Thus, D2 agonism causes
changes in the fidelity of mnemonic representations without altering
interference between memoranda.
Collapse
Affiliation(s)
| | | | | | | | - Masud Husain
- University of Oxford.,John Radcliffe Hospital, Oxford, UK
| |
Collapse
|
12
|
Norbury A, Husain M. Sensation-seeking: Dopaminergic modulation and risk for psychopathology. Behav Brain Res 2015; 288:79-93. [DOI: 10.1016/j.bbr.2015.04.015] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 04/06/2015] [Accepted: 04/10/2015] [Indexed: 12/22/2022]
|
13
|
Norbury A, Kurth-Nelson Z, Winston JS, Roiser JP, Husain M. Dopamine Regulates Approach-Avoidance in Human Sensation-Seeking. Int J Neuropsychopharmacol 2015; 18:pyv041. [PMID: 25857822 PMCID: PMC4648156 DOI: 10.1093/ijnp/pyv041] [Citation(s) in RCA: 16] [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: 12/10/2014] [Accepted: 04/03/2015] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Sensation-seeking is a trait that constitutes an important vulnerability factor for a variety of psychopathologies with high social cost. However, little is understood either about the mechanisms underlying motivation for intense sensory experiences or their neuropharmacological modulation in humans. METHODS Here, we first evaluate a novel paradigm to investigate sensation-seeking in humans. This test probes the extent to which participants choose either to avoid or self-administer an intense tactile stimulus (mild electric stimulation) orthogonal to performance on a simple economic decision-making task. Next we investigate in a different set of participants whether this behavior is sensitive to manipulation of dopamine D2 receptors using a within-subjects, placebo-controlled, double-blind design. RESULTS In both samples, individuals with higher self-reported sensation-seeking chose a greater proportion of mild electric stimulation-associated stimuli, even when this involved sacrifice of monetary gain. Computational modelling analysis determined that people who assigned an additional positive economic value to mild electric stimulation-associated stimuli exhibited speeding of responses when choosing these stimuli. In contrast, those who assigned a negative value exhibited slowed responses. These findings are consistent with involvement of low-level, approach-avoidance processes. Furthermore, the D2 antagonist haloperidol selectively decreased the additional economic value assigned to mild electric stimulation-associated stimuli in individuals who showed approach reactions to these stimuli under normal conditions (behavioral high-sensation seekers). CONCLUSIONS These findings provide the first direct evidence of sensation-seeking behavior being driven by an approach-avoidance-like mechanism, modulated by dopamine, in humans. They provide a framework for investigation of psychopathologies for which extreme sensation-seeking constitutes a vulnerability factor.
Collapse
Affiliation(s)
- Agnes Norbury
- Institute of Cognitive Neuroscience (Ms Norbury and Drs Winston and Roiser), Wellcome Trust Centre for Neuroimaging (Drs Kurth-Nelson and Winston), Max Plank-UCL Centre for Computational Psychiatry and Ageing (Dr Kurth-Nelson), University College London, London, United Kingdom; Department of Experimental Psychology and Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom (Professor Husain).
| | | | | | | | | |
Collapse
|
14
|
Molander AC, Mar A, Norbury A, Steventon S, Moreno M, Caprioli D, Theobald DEH, Belin D, Everitt BJ, Robbins TW, Dalley JW. High impulsivity predicting vulnerability to cocaine addiction in rats: some relationship with novelty preference but not novelty reactivity, anxiety or stress. Psychopharmacology (Berl) 2011; 215:721-31. [PMID: 21274702 DOI: 10.1007/s00213-011-2167-x] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Accepted: 01/05/2011] [Indexed: 11/25/2022]
Abstract
RATIONALE Impulsivity is a vulnerability marker for drug addiction in which other behavioural traits such as anxiety and novelty seeking ('sensation seeking') are also widely present. However, inter-relationships between impulsivity, novelty seeking and anxiety traits are poorly understood. OBJECTIVE The objective of this paper was to investigate the contribution of novelty seeking and anxiety traits to the expression of behavioural impulsivity in rats. METHODS Rats were screened on the five-choice serial reaction time task (5-CSRTT) for spontaneously high impulsivity (SHI) and low impulsivity (SLI) and subsequently tested for novelty reactivity and preference, assessed by open-field locomotor activity (OF), novelty place preference (NPP), and novel object recognition (OR). Anxiety was assessed on the elevated plus maze (EPM) both prior to and following the administration of the anxiolytic drug diazepam, and by blood corticosterone levels following forced novelty exposure. Finally, the effects of diazepam on impulsivity and visual attention were assessed in SHI and SLI rats. RESULTS SHI rats were significantly faster to enter an open arm on the EPM and exhibited preference for novelty in the OR and NPP tests, unlike SLI rats. However, there was no dimensional relationship between impulsivity and either novelty-seeking behaviour, anxiety levels, OF activity or novelty-induced changes in blood corticosterone levels. By contrast, diazepam (0.3-3 mg/kg), whilst not significantly increasing or decreasing impulsivity in SHI and SLI rats, did reduce the contrast in impulsivity between these two groups of animals. CONCLUSIONS This investigation indicates that behavioural impulsivity in rats on the 5-CSRTT, which predicts vulnerability for cocaine addiction, is distinct from anxiety, novelty reactivity and novelty-induced stress responses, and thus has relevance for the aetiology of drug addiction.
Collapse
Affiliation(s)
- Anna C Molander
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Downing Street, Cambridge, CB2 3EB, UK
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
15
|
Norbury A, Rocke AD, Brock-Utne JG, Mackenzie R, Welsh N, Downing JW. Balanced total intravenous anaesthesia and intraocular pressure. Anaesth Intensive Care 1981; 9:255-9. [PMID: 7283122 DOI: 10.1177/0310057x8100900308] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Twenty patients, aged 21 to 48 years and rated ASA physical status I, were studied during ophthalmic surgery. Ten subjects (Group I) received thiopentone, halothane and nitrous oxide in oxygen, and ten (Group II) received total intravenous anaesthesia, using flunitrazepam and ketamine. Ventilation was controlled mechanically with the aid of a muscle relaxant. Both anaesthetic techniques caused a significant decrease in intraocular pressure. After an initial decline in systolic arterial pressure and an increase in heart rate, cardiovascular status was well maintained in the two series. Side effects were uncommon with both techniques. Balanced total intravenous anaesthesia with flunitrazepam, ketamine and relaxant appears to offer a safe alternative to conventional inhalation narcosis for intraocular surgery.
Collapse
|