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Ramkumar R, Edge-Partington M, Terstege DJ, Adigun K, Ren Y, Khan NS, Rouhi N, Jamani NF, Tsutsui M, Epp JR, Sargin D. Long-Term Impact of Early-Life Stress on Serotonin Connectivity. Biol Psychiatry 2024; 96:287-299. [PMID: 38316332 DOI: 10.1016/j.biopsych.2024.01.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 01/04/2024] [Accepted: 01/19/2024] [Indexed: 02/07/2024]
Abstract
BACKGROUND Chronic childhood stress is a prominent risk factor for developing affective disorders, yet mechanisms underlying this association remain unclear. Maintenance of optimal serotonin (5-HT) levels during early postnatal development is critical for the maturation of brain circuits. Understanding the long-lasting effects of early-life stress (ELS) on serotonin-modulated brain connectivity is crucial to develop treatments for affective disorders arising from childhood stress. METHODS Using a mouse model of chronic developmental stress, we determined the long-lasting consequences of ELS on 5-HT circuits and behavior in females and males. Using FosTRAP mice, we cross-correlated regional c-Fos density to determine brain-wide functional connectivity of the raphe nucleus. We next performed in vivo fiber photometry to establish ELS-induced deficits in 5-HT dynamics and optogenetics to stimulate 5-HT release to improve behavior. RESULTS Adult female and male mice exposed to ELS showed heightened anxiety-like behavior. ELS further enhanced susceptibility to acute stress by disrupting the brain-wide functional connectivity of the raphe nucleus and the activity of 5-HT neuron population, in conjunction with increased orbitofrontal cortex (OFC) activity and disrupted 5-HT release in medial OFC. Optogenetic stimulation of 5-HT terminals in the medial OFC elicited an anxiolytic effect in ELS mice in a sex-dependent manner. CONCLUSIONS These findings suggest a significant disruption in 5-HT-modulated brain connectivity in response to ELS, with implications for sex-dependent vulnerability. The anxiolytic effect of the raphe-medial OFC circuit stimulation has potential implications for developing targeted stimulation-based treatments for affective disorders that arise from early life adversities.
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Affiliation(s)
- Raksha Ramkumar
- Department of Psychology, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Moriah Edge-Partington
- Department of Psychology, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Dylan J Terstege
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta, Canada; Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Kabirat Adigun
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta, Canada; Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Yi Ren
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta, Canada; Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Nazmus S Khan
- Department of Psychology, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Nahid Rouhi
- Department of Psychology, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Naila F Jamani
- Department of Psychology, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Mio Tsutsui
- Department of Psychology, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
| | - Jonathan R Epp
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta, Canada; Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Derya Sargin
- Department of Psychology, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada; Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada.
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Corradetti D, Bernardi A, Corradetti R. Deep learning models for atypical serotonergic cells recognition. J Neurosci Methods 2024; 407:110158. [PMID: 38703797 DOI: 10.1016/j.jneumeth.2024.110158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2024] [Revised: 04/15/2024] [Accepted: 04/28/2024] [Indexed: 05/06/2024]
Abstract
BACKGROUND The serotonergic system modulates brain processes via functionally distinct subpopulations of neurons with heterogeneous properties, including their electrophysiological activity. In extracellular recordings, serotonergic neurons to be investigated for their functional properties are commonly identified on the basis of "typical" features of their activity, i.e. slow regular firing and relatively long duration of action potentials. Thus, due to the lack of equally robust criteria for discriminating serotonergic neurons with "atypical" features from non-serotonergic cells, the physiological relevance of the diversity of serotonergic neuron activities results largely understudied. NEW METHODS We propose deep learning models capable of discriminating typical and atypical serotonergic neurons from non-serotonergic cells with high accuracy. The research utilized electrophysiological in vitro recordings from serotonergic neurons identified by the expression of fluorescent proteins specific to the serotonergic system and non-serotonergic cells. These recordings formed the basis of the training, validation, and testing data for the deep learning models. The study employed convolutional neural networks (CNNs), known for their efficiency in pattern recognition, to classify neurons based on the specific characteristics of their action potentials. RESULTS The models were trained on a dataset comprising 27,108 original action potential samples, alongside an extensive set of 12 million synthetic action potential samples, designed to mitigate the risk of overfitting the background noise in the recordings, a potential source of bias. Results show that the models achieved high accuracy and were further validated on "non-homogeneous" data, i.e., data unknown to the model and collected on different days from those used for the training of the model, to confirm their robustness and reliability in real-world experimental conditions. COMPARISON WITH EXISTING METHODS Conventional methods for identifying serotonergic neurons allow recognition of serotonergic neurons defined as typical. Our model based on the analysis of the sole action potential reliably recognizes over 94% of serotonergic neurons including those with atypical features of spike and activity. CONCLUSION The model is ready for use in experiments conducted with the here described recording parameters. We release the codes and procedures allowing to adapt the model to different acquisition parameters or for identification of other classes of spontaneously active neurons.
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Affiliation(s)
- Daniele Corradetti
- Grupo de Fisica Matematica, Instituto Superior Tecnico, Av. Rovisco Pais, Lisboa, 1049-001, Portugal; Departamento de Matematica, Universidade do Algarve, Campus de Gambelas, Faro, 8005-139, Faro, Portugal.
| | | | - Renato Corradetti
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Viale G. Pieraccini 6, Firenze, 50139, Toscana, Italy.
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Costello H, Husain M, Roiser JP. Apathy and Motivation: Biological Basis and Drug Treatment. Annu Rev Pharmacol Toxicol 2024; 64:313-338. [PMID: 37585659 DOI: 10.1146/annurev-pharmtox-022423-014645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/18/2023]
Abstract
Apathy is a disabling syndrome associated with poor functional outcomes that is common across a broad range of neurological and psychiatric conditions. Currently, there are no established therapies specifically for the condition, and safe and effective treatments are urgently needed. Advances in the understanding of motivation and goal-directed behavior in humans and animals have shed light on the cognitive and neurobiological mechanisms contributing to apathy, providing an important foundation for the development of new treatments. Here, we review the cognitive components, neural circuitry, and pharmacology of apathy and motivation, highlighting converging evidence of shared transdiagnostic mechanisms. Though no pharmacological treatments have yet been licensed, we summarize trials of existing and novel compounds to date, identifying several promising candidates for clinical use and avenues of future drug development.
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Affiliation(s)
- Harry Costello
- Institute of Cognitive Neuroscience, University College London, London, United Kingdom;
| | - Masud Husain
- Nuffield Department of Clinical Neurosciences and Department of Experimental Psychology, Oxford University, Oxford, United Kingdom
| | - Jonathan P Roiser
- Institute of Cognitive Neuroscience, University College London, London, United Kingdom;
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4
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Chi HC, Ma LZ, Wang ZB, Sheng ZH, Liu JY, Mi YC, Fu Y, Huang YM, Han SL, Gao PY, Tan L, Yu JT. Associations of Frailty with Neuropsychiatric Symptoms of Alzheimer's Disease: A Longitudinal Study. J Alzheimers Dis 2024; 98:629-642. [PMID: 38427482 DOI: 10.3233/jad-231111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2024]
Abstract
Background Frailty is a vulnerability state increasing the risk of many adverse health outcomes, but little is known about the effects of frailty on neuropsychiatric health. Objective To explore the associations between frailty and the risk of neuropsychiatric symptoms (NPSs) in Alzheimer's disease (AD), especially in its different clinical stages. Methods We included 2,155 individuals assessed using modified frailty index-11 (mFI-11), Neuropsychiatric Inventory (NPI) and Neuropsychiatric Inventory Questionnaire (NPI-Q) in the Alzheimer's Disease Neuroimaging Initiative (ADNI). The relationships between frailty and NPSs were explored with logistic regression models and Cox proportional hazard regression models. Causal mediation analyses were conducted to explore the mediation factors between frailty and NPSs. Results Among mild cognitive impairment (MCI) participants, frailty was cross-sectionally associated with an increased risk of apathy, and longitudinally associated with increased risk of depression and apathy. Among AD participants, frailty was cross-sectionally associated with increased risk of depression and anxiety, and longitudinally associated with an increased risk of apathy. Among participants with cognitive progression, frailty was associated with increased risk of depression and apathy. In MCI participants, the influence of frailty on NPSs was partially mediated by hippocampus volume, whole brain volume, and monocytes, with mediating proportions ranging from 8.40% to 9.29%. Conclusions Frailty was associated with NPSs such as depression, anxiety, and apathy among MCI, AD, and cognitive progression participants. Atrophy of the hippocampus and whole brain, as well as peripheral immunity may be involved in the potential mechanisms underlying the above associations.
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Affiliation(s)
- Hao-Chen Chi
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Ling-Zhi Ma
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Zhi-Bo Wang
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Ze-Hu Sheng
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Jia-Yao Liu
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Yin-Chu Mi
- Department of Neurology, Qingdao Municipal Hospital, Dalian Medical University, Dalian, China
| | - Yan Fu
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Yi-Ming Huang
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Shuang-Ling Han
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Pei-Yang Gao
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Lan Tan
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Jin-Tai Yu
- Department of Neurology and National Center for Neurological Disorders, Huashan Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Shanghai Medical College, Fudan University, Shanghai, China
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Carvalheiro J, Philiastides MG. Distinct spatiotemporal brainstem pathways of outcome valence during reward- and punishment-based learning. Cell Rep 2023; 42:113589. [PMID: 38100353 DOI: 10.1016/j.celrep.2023.113589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 10/05/2023] [Accepted: 11/30/2023] [Indexed: 12/17/2023] Open
Abstract
Learning to seek rewards and avoid punishments, based on positive and negative choice outcomes, is essential for human survival. Yet, the neural underpinnings of outcome valence in the human brainstem and the extent to which they differ in reward and punishment learning contexts remain largely elusive. Here, using simultaneously acquired electroencephalography and functional magnetic resonance imaging data, we show that during reward learning the substantia nigra (SN)/ventral tegmental area (VTA) and locus coeruleus are initially activated following negative outcomes, while the VTA subsequently re-engages exhibiting greater responses for positive than negative outcomes, consistent with an early arousal/avoidance response and a later value-updating process, respectively. During punishment learning, we show that distinct raphe nucleus and SN subregions are activated only by negative outcomes with a sustained post-outcome activity across time, supporting the involvement of these brainstem subregions in avoidance behavior. Finally, we demonstrate that the coupling of these brainstem structures with other subcortical and cortical areas helps to shape participants' serial choice behavior in each context.
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Affiliation(s)
- Joana Carvalheiro
- School of Psychology and Neuroscience, University of Glasgow, Glasgow G12 8QB, UK; Centre for Cognitive Neuroimaging, University of Glasgow, Glasgow G12 8QB, UK.
| | - Marios G Philiastides
- School of Psychology and Neuroscience, University of Glasgow, Glasgow G12 8QB, UK; Centre for Cognitive Neuroimaging, University of Glasgow, Glasgow G12 8QB, UK.
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Bîlc MI, Iacob A, Szekely-Copîndean RD, Kiss B, Ștefan MG, Mureșan RC, Pop CF, Pițur S, Szentágotai-Tătar A, Vulturar R, MacLeod C, Miu AC. Serotonin and emotion regulation: the impact of tryptophan depletion on emotional experience, neural and autonomic activity. COGNITIVE, AFFECTIVE & BEHAVIORAL NEUROSCIENCE 2023; 23:1414-1427. [PMID: 37430145 DOI: 10.3758/s13415-023-01116-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/09/2023] [Indexed: 07/12/2023]
Abstract
The involvement of serotonin in emotion and psychopathology has been extensively examined. Studies using acute tryptophan depletion (ATD) have found limited effects on mood and aggression, and one of the explanations suggests that serotonin may be involved in higher-order functions, such as emotion regulation. However, there is very limited evidence for this hypothesis. The present study investigated the impact of ATD on emotion regulation in a double-blind, placebo-controlled, crossover design. A sample of psychiatrically healthy men (N = 28) completed a cognitive task assessing reappraisal ability (i.e., the success of using reappraisal, an emotion regulation strategy, to modulate emotional responses), following ATD and placebo. EEG frontal activity and asymmetry, as well as heart-rate variability (HRV), also were assessed in the reappraisal task. Both frequentist and Bayesian methods were employed for statistical analysis. Results indicated that ATD reduced plasma tryptophan, and reappraisal was effective in modulating emotional experience in the emotion regulation task. However, ATD had no significant effect on reappraisal ability, frontal activity, and HRV. These results offer direct and compelling evidence that decreasing serotonin synthesis through ATD does not alter an emotion regulation ability that is considered crucial in mood and aggression and has been linked with transdiagnostic risk of psychopathology.
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Affiliation(s)
- Mirela I Bîlc
- Cognitive Neuroscience Laboratory, Department of Psychology, Babeș-Bolyai University, 37 Republicii Street, Cluj-Napoca, 400015, Cluj-Napoca, Romania
- Institute of Medical Psychology, Medical Faculty, Otto-von-Guericke University of Magdeburg, Magdeburg, Germany
| | - Alexandra Iacob
- Cognitive Neuroscience Laboratory, Department of Psychology, Babeș-Bolyai University, 37 Republicii Street, Cluj-Napoca, 400015, Cluj-Napoca, Romania
| | - Raluca D Szekely-Copîndean
- Cognitive Neuroscience Laboratory, Department of Psychology, Babeș-Bolyai University, 37 Republicii Street, Cluj-Napoca, 400015, Cluj-Napoca, Romania
- Department of Social and Human Research, Romanian Academy, Cluj-Napoca, Romania
| | - Béla Kiss
- Department of Toxicology, Faculty of Pharmacy, "Iuliu Hațieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Maria-Georgia Ștefan
- Department of Toxicology, Faculty of Pharmacy, "Iuliu Hațieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Raul C Mureșan
- Department of Experimental and Theoretical Neuroscience, Transylvanian Institute of Neuroscience, Cluj-Napoca, Romania
- STAR-UBB Institute, Babeș-Bolyai University, Cluj-Napoca, Romania
| | - Claudia Felicia Pop
- Nursing Discipline, Department Mother and Child, "Iuliu Hațieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Simina Pițur
- Cognitive Neuroscience Laboratory, Department of Psychology, Babeș-Bolyai University, 37 Republicii Street, Cluj-Napoca, 400015, Cluj-Napoca, Romania
| | - Aurora Szentágotai-Tătar
- Department of Clinical Psychology and Psychotherapy, Babeș-Bolyai University, Cluj-Napoca, Romania
| | - Romana Vulturar
- Cognitive Neuroscience Laboratory, Department of Psychology, Babeș-Bolyai University, 37 Republicii Street, Cluj-Napoca, 400015, Cluj-Napoca, Romania.
- Department of Molecular Sciences, "Iuliu Hațieganu" University of Medicine and Pharmacy, 6 Pasteur Street, 400349, Cluj-Napoca, Romania.
| | - Colin MacLeod
- Cognitive Neuroscience Laboratory, Department of Psychology, Babeș-Bolyai University, 37 Republicii Street, Cluj-Napoca, 400015, Cluj-Napoca, Romania
- Centre for the Advancement of Research on Emotion, School of Psychological Science, The University of Western Australia, Crawley, Australia
| | - Andrei C Miu
- Cognitive Neuroscience Laboratory, Department of Psychology, Babeș-Bolyai University, 37 Republicii Street, Cluj-Napoca, 400015, Cluj-Napoca, Romania.
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Steding J, Ritschel F, Boehm I, Geisler D, King JA, Roessner V, Smolka MN, Zepf FD, Ehrlich S. The effects of acute tryptophan depletion on instrumental reward learning in anorexia nervosa - an fMRI study. Psychol Med 2023; 53:3426-3436. [PMID: 35343412 PMCID: PMC10277771 DOI: 10.1017/s0033291721005493] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 10/15/2021] [Accepted: 12/20/2021] [Indexed: 11/07/2022]
Abstract
BACKGROUND The serotonin (5-HT) hypothesis of anorexia nervosa (AN) posits that individuals predisposed toward or recovered from AN (recAN) have a central nervous hyperserotonergic state and therefore restrict food intake as a means to reduce 5-HT availability (via diminished tryptophan-derived precursor supply) and alleviate associated negative mood states. Importantly, the 5-HT system has also been generally implicated in reward processing, which has also been shown to be altered in AN. METHODS In this double-blind crossover study, 22 individuals recAN and 25 healthy control participants (HC) underwent functional magnetic resonance imaging (fMRI) while performing an established instrumental reward learning paradigm during acute tryptophan depletion (ATD; a dietary intervention that lowers central nervous 5-HT availability) as well as a sham depletion. RESULTS On a behavioral level, the main effects of reward and ATD were evident, but no group differences were found. fMRI analyses revealed a group × ATD × reward level interaction in the ventral anterior insula during reward anticipation as well as in the medial orbitofrontal cortex during reward consumption. DISCUSSION The precise pattern of results is suggestive of a 'normalization' of reward-related neural responses during ATD in recAN compared to HC. Our results lend further evidence to the 5-HT hypothesis of AN. Decreasing central nervous 5-HT synthesis and availability during ATD and possibly also by dieting may be a means to normalize 5-HT availability and associated brain processes.
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Affiliation(s)
- Julius Steding
- Translational Developmental Neuroscience Section, Division of Psychological and Social Medicine and Developmental Neurosciences, Faculty of Medicine, TU Dresden, Dresden, Germany
| | - Franziska Ritschel
- Translational Developmental Neuroscience Section, Division of Psychological and Social Medicine and Developmental Neurosciences, Faculty of Medicine, TU Dresden, Dresden, Germany
| | - Ilka Boehm
- Translational Developmental Neuroscience Section, Division of Psychological and Social Medicine and Developmental Neurosciences, Faculty of Medicine, TU Dresden, Dresden, Germany
| | - Daniel Geisler
- Translational Developmental Neuroscience Section, Division of Psychological and Social Medicine and Developmental Neurosciences, Faculty of Medicine, TU Dresden, Dresden, Germany
| | - Joseph A. King
- Translational Developmental Neuroscience Section, Division of Psychological and Social Medicine and Developmental Neurosciences, Faculty of Medicine, TU Dresden, Dresden, Germany
| | - Veit Roessner
- Department of Child and Adolescent Psychiatry, Faculty of Medicine, University Hospital C. G. Carus, Technische Universität Dresden, Dresden, Germany
| | - Michael N. Smolka
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Florian Daniel Zepf
- Department of Child and Adolescent Psychiatry, Psychosomatic Medicine and Psychotherapy, Jena University Hospital, Friedrich Schiller University, Jena, Germany
| | - Stefan Ehrlich
- Translational Developmental Neuroscience Section, Division of Psychological and Social Medicine and Developmental Neurosciences, Faculty of Medicine, TU Dresden, Dresden, Germany
- Eating Disorder Treatment and Research Center, Department of Child and Adolescent Psychiatry, Faculty of Medicine, Technische Universität Dresden, Dresden, Germany
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Griebsch NI, Kern J, Hansen J, Rullmann M, Luthardt J, Helfmeyer S, Dekorsy FJ, Soeder M, Hankir MK, Zientek F, Becker GA, Patt M, Meyer PM, Dietrich A, Blüher M, Ding YS, Hilbert A, Sabri O, Hesse S. Central Serotonin/Noradrenaline Transporter Availability and Treatment Success in Patients with Obesity. Brain Sci 2022; 12:brainsci12111437. [PMID: 36358364 PMCID: PMC9688491 DOI: 10.3390/brainsci12111437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 09/30/2022] [Accepted: 10/13/2022] [Indexed: 12/04/2022] Open
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) as well as noradrenaline (NA) are key modulators of various fundamental brain functions including the control of appetite. While manipulations that alter brain serotoninergic signaling clearly affect body weight, studies implicating 5-HT transporters and NA transporters (5-HTT and NAT, respectively) as a main drug treatment target for human obesity have not been conclusive. The aim of this positron emission tomography (PET) study was to investigate how these central transporters are associated with changes of body weight after 6 months of dietary intervention or Roux-en-Y gastric bypass (RYGB) surgery in order to assess whether 5-HTT as well as NAT availability can predict weight loss and consequently treatment success. The study population consisted of two study cohorts using either the 5-HTT-selective radiotracer [11C]DASB to measure 5-HTT availability or the NAT-selective radiotracer [11C]MRB to assess NAT availability. Each group included non-obesity healthy participants, patients with severe obesity (body mass index, BMI, >35 kg/m2) following a conservative dietary program (diet) and patients undergoing RYGB surgery within a 6-month follow-up. Overall, changes in BMI were not associated with changes of both 5-HTT and NAT availability, while 5-HTT availability in the dorsal raphe nucleus (DRN) prior to intervention was associated with substantial BMI reduction after RYGB surgery and inversely related with modest BMI reduction after diet. Taken together, the data of our study indicate that 5-HTT and NAT are involved in the pathomechanism of obesity and have the potential to serve as predictors of treatment outcomes.
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Affiliation(s)
| | - Johanna Kern
- Department of Nuclear Medicine, University of Leipzig, 04103 Leipzig, Germany
| | - Jonas Hansen
- Integrated Research and Treatment Center Adiposity Diseases, 04103 Leipzig, Germany
- Department of Pneumology, Jena University Hospital, University of Jena, 07747 Jena, Germany
| | - Michael Rullmann
- Department of Nuclear Medicine, University of Leipzig, 04103 Leipzig, Germany
| | - Julia Luthardt
- Department of Nuclear Medicine, University of Leipzig, 04103 Leipzig, Germany
| | - Stephanie Helfmeyer
- Integrated Research and Treatment Center Adiposity Diseases, 04103 Leipzig, Germany
- Institute of Nutritional Sciences, Friedrich-Schiller-Universität Jena, 07743 Jena, Germany
| | - Franziska J. Dekorsy
- Department of Nuclear Medicine, University Hospital, Ludwig Maximilian University of Munich, 81377 Munich, Germany
| | - Marvin Soeder
- Integrated Research and Treatment Center Adiposity Diseases, 04103 Leipzig, Germany
| | - Mohammed K. Hankir
- Department of Experimental Surgery, University Hospital Würzburg, 97080 Würzburg, Germany
| | - Franziska Zientek
- Department of Nuclear Medicine, University of Leipzig, 04103 Leipzig, Germany
- Integrated Research and Treatment Center Adiposity Diseases, 04103 Leipzig, Germany
| | | | - Marianne Patt
- Department of Nuclear Medicine, University of Leipzig, 04103 Leipzig, Germany
| | - Philipp M. Meyer
- Department of Nuclear Medicine, University of Leipzig, 04103 Leipzig, Germany
- Integrated Research and Treatment Center Adiposity Diseases, 04103 Leipzig, Germany
| | - Arne Dietrich
- Integrated Research and Treatment Center Adiposity Diseases, 04103 Leipzig, Germany
- Department of Abdominal, Transplant, Thoracic and Vascular Surgery, University Hospital Leipzig, 04103 Leipzig, Germany
| | - Matthias Blüher
- Medical Department III-Endocrinology, Nephrology, Rheumatology, University of Leipzig Medical Center, Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig, 04103 Leipzig, Germany
| | - Yu-Shin Ding
- Departments of Radiology and Psychiatry, New York University School of Medicine, New York, NY 10016, USA
| | - Anja Hilbert
- Integrated Research and Treatment Center Adiposity Diseases, 04103 Leipzig, Germany
- Behavioral Medicine Research Unit, Department of Psychosomatic Medicine and Psychotherapy, 04103 Leipzig, Germany
| | - Osama Sabri
- Department of Nuclear Medicine, University of Leipzig, 04103 Leipzig, Germany
| | - Swen Hesse
- Department of Nuclear Medicine, University of Leipzig, 04103 Leipzig, Germany
- Integrated Research and Treatment Center Adiposity Diseases, 04103 Leipzig, Germany
- Correspondence:
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Michely J, Eldar E, Erdman A, Martin IM, Dolan RJ. Serotonin modulates asymmetric learning from reward and punishment in healthy human volunteers. Commun Biol 2022; 5:812. [PMID: 35962142 PMCID: PMC9374781 DOI: 10.1038/s42003-022-03690-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 07/08/2022] [Indexed: 11/15/2022] Open
Abstract
Instrumental learning is driven by a history of outcome success and failure. Here, we examined the impact of serotonin on learning from positive and negative outcomes. Healthy human volunteers were assessed twice, once after acute (single-dose), and once after prolonged (week-long) daily administration of the SSRI citalopram or placebo. Using computational modelling, we show that prolonged boosting of serotonin enhances learning from punishment and reduces learning from reward. This valence-dependent learning asymmetry increases subjects' tendency to avoid actions as a function of cumulative failure without leading to detrimental, or advantageous, outcomes. By contrast, no significant modulation of learning was observed following acute SSRI administration. However, differences between the effects of acute and prolonged administration were not significant. Overall, these findings may help explain how serotonergic agents impact on mood disorders.
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Affiliation(s)
- Jochen Michely
- Department of Psychiatry and Neurosciences, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.
- Berlin Institute of Health at Charité - Universitätsmedizin Berlin, BIH Charité Clinician Scientist Program, Berlin, Germany.
- Max Planck UCL Centre for Computational Psychiatry and Ageing Research, University College London, London, UK.
- Wellcome Centre for Human Neuroimaging, University College London, London, UK.
| | - Eran Eldar
- Psychology and Cognitive Sciences Departments, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Alon Erdman
- Psychology and Cognitive Sciences Departments, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Ingrid M Martin
- Wellcome Centre for Human Neuroimaging, University College London, London, UK
- Institute of Cognitive Neuroscience, University College London, London, UK
| | - Raymond J Dolan
- Max Planck UCL Centre for Computational Psychiatry and Ageing Research, University College London, London, UK
- Wellcome Centre for Human Neuroimaging, University College London, London, UK
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10
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Kanen JW, Robbins TW, Trofimova IN. Harnessing temperament to elucidate the complexities of serotonin function. Curr Opin Behav Sci 2022. [DOI: 10.1016/j.cobeha.2022.101108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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11
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Gilbert JR, Wusinich C, Zarate CA. A Predictive Coding Framework for Understanding Major Depression. Front Hum Neurosci 2022; 16:787495. [PMID: 35308621 PMCID: PMC8927302 DOI: 10.3389/fnhum.2022.787495] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 02/14/2022] [Indexed: 12/17/2022] Open
Abstract
Predictive coding models of brain processing propose that top-down cortical signals promote efficient neural signaling by carrying predictions about incoming sensory information. These "priors" serve to constrain bottom-up signal propagation where prediction errors are carried via feedforward mechanisms. Depression, traditionally viewed as a disorder characterized by negative cognitive biases, is associated with disrupted reward prediction error encoding and signaling. Accumulating evidence also suggests that depression is characterized by impaired local and long-range prediction signaling across multiple sensory domains. This review highlights the electrophysiological and neuroimaging evidence for disrupted predictive processing in depression. The discussion is framed around the manner in which disrupted generative predictions about the sensorium could lead to depressive symptomatology, including anhedonia and negative bias. In particular, the review focuses on studies of sensory deviance detection and reward processing, highlighting research evidence for both disrupted generative predictions and prediction error signaling in depression. The role of the monoaminergic and glutamatergic systems in predictive coding processes is also discussed. This review provides a novel framework for understanding depression using predictive coding principles and establishes a foundational roadmap for potential future research.
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Affiliation(s)
- Jessica R. Gilbert
- Experimental Therapeutics and Pathophysiology Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, United States
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12
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Yee DM, Leng X, Shenhav A, Braver TS. Aversive motivation and cognitive control. Neurosci Biobehav Rev 2022; 133:104493. [PMID: 34910931 PMCID: PMC8792354 DOI: 10.1016/j.neubiorev.2021.12.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 11/12/2021] [Accepted: 12/09/2021] [Indexed: 02/03/2023]
Abstract
Aversive motivation plays a prominent role in driving individuals to exert cognitive control. However, the complexity of behavioral responses attributed to aversive incentives creates significant challenges for developing a clear understanding of the neural mechanisms of this motivation-control interaction. We review the animal learning, systems neuroscience, and computational literatures to highlight the importance of experimental paradigms that incorporate both motivational context manipulations and mixed motivational components (e.g., bundling of appetitive and aversive incentives). Specifically, we postulate that to understand aversive incentive effects on cognitive control allocation, a critical contextual factor is whether such incentives are associated with negative reinforcement or punishment. We further illustrate how the inclusion of mixed motivational components in experimental paradigms enables increased precision in the measurement of aversive influences on cognitive control. A sharpened experimental and theoretical focus regarding the manipulation and assessment of distinct motivational dimensions promises to advance understanding of the neural, monoaminergic, and computational mechanisms that underlie the interaction of motivation and cognitive control.
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Affiliation(s)
- Debbie M Yee
- Cognitive, Linguistic, and Psychological Sciences, Brown University, USA; Carney Institute for Brain Science, Brown University, USA; Department of Psychological and Brain Sciences, Washington University in Saint Louis, USA.
| | - Xiamin Leng
- Cognitive, Linguistic, and Psychological Sciences, Brown University, USA; Carney Institute for Brain Science, Brown University, USA
| | - Amitai Shenhav
- Cognitive, Linguistic, and Psychological Sciences, Brown University, USA; Carney Institute for Brain Science, Brown University, USA
| | - Todd S Braver
- Department of Psychological and Brain Sciences, Washington University in Saint Louis, USA
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13
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Courtiol E, Menezes EC, Teixeira CM. Serotonergic regulation of the dopaminergic system: Implications for reward-related functions. Neurosci Biobehav Rev 2021; 128:282-293. [PMID: 34139249 PMCID: PMC8335358 DOI: 10.1016/j.neubiorev.2021.06.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 05/11/2021] [Accepted: 06/10/2021] [Indexed: 12/17/2022]
Abstract
Serotonin is a critical neuromodulator involved in development and behavior. Its role in reward is however still debated. Here, we first review classical studies involving electrical stimulation protocols and pharmacological approaches. Contradictory results on the serotonergic' involvement in reward emerge from these studies. These differences might be ascribable to either the diversity of cellular types within the raphe nuclei or/and the specific projection pathways of serotonergic neurons. We continue to review more recent work, using optogenetic approaches to activate serotonergic cells in the Raphe to VTA pathway. From these studies, it appears that activation of this pathway can lead to reinforcement learning mediated through the excitation of dopaminergic neurons by serotonergic neurons co-transmitting glutamate. Finally, given the importance of serotonin during development on adult emotion, the effect of abnormal early-life levels of serotonin on the dopaminergic system will also be discussed. Understanding the interaction between the serotonergic and dopaminergic systems during development and adulthood is critical to gain insight into the specific facets of neuropsychiatric disorders.
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Affiliation(s)
- Emmanuelle Courtiol
- Lyon Neuroscience Research Center, UMR 5292- INSERM U1028- Université Lyon 1, 69675 Bron Cedex, France
| | - Edenia C Menezes
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, United States
| | - Catia M Teixeira
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY 10962, United States; Department of Child and Adolescent Psychiatry, New York University Grossman School of Medicine, New York, NY 10016, United States.
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14
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Reed MB, Vanicek T, Seiger R, Klöbl M, Spurny B, Handschuh P, Ritter V, Unterholzner J, Godbersen GM, Gryglewski G, Kraus C, Winkler D, Hahn A, Lanzenberger R. Neuroplastic effects of a selective serotonin reuptake inhibitor in relearning and retrieval. Neuroimage 2021; 236:118039. [PMID: 33852940 PMCID: PMC7610799 DOI: 10.1016/j.neuroimage.2021.118039] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 02/19/2021] [Accepted: 04/02/2021] [Indexed: 12/17/2022] Open
Abstract
Animal studies using selective serotonin reuptake inhibitors (SSRIs) and learning paradigms have demonstrated that serotonin is important for flexibility in executive functions and learning. SSRIs might facilitate relearning through neuroplastic processes and thus exert their clinical effects in psychiatric diseases where cognitive functioning is affected. However, translation of these mechanisms to humans is missing. In this randomized placebo-controlled trial, we assessed functional brain activation during learning and memory retrieval in healthy volunteers performing associative learning tasks aiming to translate facilitated relearning by SSRIs. To this extent, seventy-six participants underwent three MRI scanning sessions: (1) at baseline, (2) after three weeks of daily associative learning and subsequent retrieval (face-matching or Chinese character–noun matching) and (3) after three weeks of relearning under escitalopram (10 mg/day) or placebo. Associative learning and retrieval tasks were performed during each functional MRI (fMRI) session. Statistical modeling was done using a repeated-measures ANOVA, to test for content-by-treatment-by-time interaction effects. During the learning task, a significant substance-by-time interaction was found in the right insula showing a greater deactivation in the SSRI cohort after 21 days of relearning compared to the learning phase. In the retrieval task, there was a significant content-by-time interaction in the left angular gyrus (AG) with an increased activation in face-matching compared to Chinese-character matching for both learning and relearning phases. A further substance-by-time interaction was found in task performance after 21 days of relearning, indicating a greater decrease of performance in the placebo group. Our findings that escitalopram modulate insula activation demonstrates successful translation of relearning as a mechanism of SSRIs in human. Furthermore, we show that the left AG is an active component of correct memory retrieval, which coincides with previous literature. We extend the function of this region by demonstrating its activation is not only stimulus dependent but also time constrained. Finally, we were able to show that escitalopram aids in relearning, irrespective of content.
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Affiliation(s)
- M B Reed
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - T Vanicek
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - R Seiger
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - M Klöbl
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - B Spurny
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - P Handschuh
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - V Ritter
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - J Unterholzner
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - G M Godbersen
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - G Gryglewski
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - C Kraus
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - D Winkler
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - A Hahn
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria
| | - R Lanzenberger
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria.
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15
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Carneiro-Nascimento S, Powell W, Uebel M, Buerge M, Sigrist H, Patterson M, Pryce CR, Opacka-Juffry J. Region- and receptor-specific effects of chronic social stress on the central serotonergic system in mice. IBRO Neurosci Rep 2021; 10:8-16. [PMID: 33861815 PMCID: PMC8019833 DOI: 10.1016/j.ibneur.2020.11.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 11/27/2020] [Indexed: 10/25/2022] Open
Abstract
Serotonin (5-HT), via its receptors expressed in discrete brain regions, modulates aversion and reward processing and is implicated in various psychiatric disorders including depression. Stressful experiences affect central serotonergic activity and act as a risk factor for depression; this can be modelled preclinically. In adult male C57BL/6J mice, 15-day chronic social stress (CSS) leads to depression-relevant behavioural states, including increased aversion and reduced reward sensitivity. Based on this evidence, here we investigated CSS effects on 5-HT1A, 5-HT2A, and 5-HT2C receptor binding in discrete brain regions using in vitro quantitative autoradiography with selective radioligands. In addition, mRNA expression of Htr1a, 2a, 2c and Slc6a4 (5-HT transporter) was measured by quantitative PCR. Relative to controls, the following effects were observed in CSS mice: 5-HT1A receptor binding was markedly increased in the dorsal raphe nucleus (136%); Htr1a mRNA expression was increased in raphe nuclei (19%), medial prefrontal cortex (35%), and hypothalamic para- and periventricular nuclei (21%) and ventral medial nucleus (38%). 5-HT2A receptor binding was decreased in the amygdala (48%) and ventral tegmental area (60%); Htr2a mRNA expression was increased in the baso-lateral amygdala (116%). 5-HT2C receptor binding was decreased in the dorsal raphe nucleus (42%). Slc6a4 mRNA expression was increased in the raphe (59%). The present findings add to the translational evidence that chronic social stress impacts on the central serotonergic system in a region- and receptor-specific manner, and that this altered state of the serotonergic system contributes to stress-induced dysfunctions in emotional processing.
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Affiliation(s)
| | - William Powell
- Department of Life Sciences, University of Roehampton, London SW15 4JD, UK
| | - Michaela Uebel
- Department of Life Sciences, University of Roehampton, London SW15 4JD, UK
| | - Michaela Buerge
- Preclinical Laboratory for Translational Research into Affective Disorders, Department of Psychiatry, Psychotherapy & Psychosomatics, University of Zurich, Zurich, Switzerland
| | - Hannes Sigrist
- Preclinical Laboratory for Translational Research into Affective Disorders, Department of Psychiatry, Psychotherapy & Psychosomatics, University of Zurich, Zurich, Switzerland
| | - Michael Patterson
- Department of Life Sciences, University of Roehampton, London SW15 4JD, UK
| | - Christopher R Pryce
- Preclinical Laboratory for Translational Research into Affective Disorders, Department of Psychiatry, Psychotherapy & Psychosomatics, University of Zurich, Zurich, Switzerland
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16
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Abstract
This paper introduces a new construct, the 'pivotal mental state', which is defined as a hyper-plastic state aiding rapid and deep learning that can mediate psychological transformation. We believe this new construct bears relevance to a broad range of psychological and psychiatric phenomena. We argue that pivotal mental states serve an important evolutionary function, that is, to aid psychological transformation when actual or perceived environmental pressures demand this. We cite evidence that chronic stress and neurotic traits are primers for a pivotal mental state, whereas acute stress can be a trigger. Inspired by research with serotonin 2A receptor agonist psychedelics, we highlight how activity at this particular receptor can robustly and reliably induce pivotal mental states, but we argue that the capacity for pivotal mental states is an inherent property of the human brain itself. Moreover, we hypothesize that serotonergic psychedelics hijack a system that has evolved to mediate rapid and deep learning when its need is sensed. We cite a breadth of evidences linking stress via a variety of inducers, with an upregulated serotonin 2A receptor system (e.g. upregulated availability of and/or binding to the receptor) and acute stress with 5-HT release, which we argue can activate this primed system to induce a pivotal mental state. The pivotal mental state model is multi-level, linking a specific molecular gateway (increased serotonin 2A receptor signaling) with the inception of a hyper-plastic brain and mind state, enhanced rate of associative learning and the potential mediation of a psychological transformation.
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Affiliation(s)
- Ari Brouwer
- Centre for Psychedelic Research, Imperial College London, London, United Kingdom
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17
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Liu L, Artigas SO, Ulrich A, Tardu J, Mohr PNC, Wilms B, Koletzko B, Schmid SM, Park SQ. Eating to dare - Nutrition impacts human risky decision and related brain function. Neuroimage 2021; 233:117951. [PMID: 33722669 DOI: 10.1016/j.neuroimage.2021.117951] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 03/02/2021] [Accepted: 03/06/2021] [Indexed: 10/21/2022] Open
Abstract
Macronutrient composition modulates plasma amino acids that are precursors of neurotransmitters and can impact brain function and decisions. Neurotransmitter serotonin has been shown to regulate not only food intake, but also economic decisions. We investigated whether an acute nutrition-manipulation inducing plasma tryptophan fluctuation affects brain function, thereby affecting risky decisions. Breakfasts differing in carbohydrate/protein ratios were offered to test changes in risky decision-making while metabolic and neural dynamics were tracked. We identified that a high-carbohydrate/protein breakfast increased plasma tryptophan/LNAA (large neutral amino acids) ratio which mapped to individual risk propensity changes. The nutrition-manipulation and tryptophan/LNAA fluctuation effects on risk propensity changes were further modulated by individual differences in body fat mass. Using fMRI, we further identified activation in the parietal lobule during risk-processing, of which activities 1) were sensitive to the tryptophan/LNAA fluctuation, 2) were modulated by individual's body fat mass, and 3) predicted the risk propensity changes in decision-making. Our results provide evidence for a personalized nutrition-driven modulation on human risky decision and its metabolic and neural mechanisms.
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Affiliation(s)
- Lu Liu
- Department of Decision Neuroscience & Nutrition, German Institute of Human Nutrition (DIfE), Nuthetal, Germany; Department of Psychology, University of Lübeck, Lübeck, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany.
| | | | - Anja Ulrich
- Institute for Endocrinology & Diabetes, University of Lübeck, Lübeck, Germany
| | - Jeremy Tardu
- Institute for Endocrinology & Diabetes, University of Lübeck, Lübeck, Germany
| | - Peter N C Mohr
- School of Business and Economics, Freie Universität Berlin, Germany; WZB Berlin Social Science Center, Berlin, Germany; Center for Cognitive Neuroscience Berlin, Freie Universität Berlin, Berlin, Germany
| | - Britta Wilms
- German Center for Diabetes Research (DZD), Neuherberg, Germany; Institute for Endocrinology & Diabetes, University of Lübeck, Lübeck, Germany
| | - Berthold Koletzko
- Dr. von Hauner Children's Hospital, University of Munich Medical Center, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Sebastian M Schmid
- German Center for Diabetes Research (DZD), Neuherberg, Germany; Institute for Endocrinology & Diabetes, University of Lübeck, Lübeck, Germany
| | - Soyoung Q Park
- Department of Decision Neuroscience & Nutrition, German Institute of Human Nutrition (DIfE), Nuthetal, Germany; Department of Psychology, University of Lübeck, Lübeck, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany; Neuroscience Research Center, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Neuroscience Research Center, Berlin, Germany.
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18
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Serotonin depletion impairs both Pavlovian and instrumental reversal learning in healthy humans. Mol Psychiatry 2021; 26:7200-7210. [PMID: 34429517 PMCID: PMC8873011 DOI: 10.1038/s41380-021-01240-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 07/03/2021] [Accepted: 07/09/2021] [Indexed: 02/07/2023]
Abstract
Serotonin is involved in updating responses to changing environmental circumstances. Optimising behaviour to maximise reward and minimise punishment may require shifting strategies upon encountering new situations. Likewise, autonomic responses to threats are critical for survival yet must be modified as danger shifts from one source to another. Whilst numerous psychiatric disorders are characterised by behavioural and autonomic inflexibility, few studies have examined the contribution of serotonin in humans. We modelled both processes, respectively, in two independent experiments (N = 97). Experiment 1 assessed instrumental (stimulus-response-outcome) reversal learning whereby individuals learned through trial and error which action was most optimal for obtaining reward or avoiding punishment initially, and the contingencies subsequently reversed serially. Experiment 2 examined Pavlovian (stimulus-outcome) reversal learning assessed by the skin conductance response: one innately threatening stimulus predicted receipt of an uncomfortable electric shock and another did not; these contingencies swapped in a reversal phase. Upon depleting the serotonin precursor tryptophan-in a double-blind randomised placebo-controlled design-healthy volunteers showed impairments in updating both actions and autonomic responses to reflect changing contingencies. Reversal deficits in each domain, furthermore, were correlated with the extent of tryptophan depletion. Initial Pavlovian conditioning, moreover, which involved innately threatening stimuli, was potentiated by depletion. These results translate findings in experimental animals to humans and have implications for the neurochemical basis of cognitive inflexibility.
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19
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The Emerging Role of LHb CaMKII in the Comorbidity of Depressive and Alcohol Use Disorders. Int J Mol Sci 2020; 21:ijms21218123. [PMID: 33143210 PMCID: PMC7663385 DOI: 10.3390/ijms21218123] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 10/22/2020] [Accepted: 10/26/2020] [Indexed: 01/05/2023] Open
Abstract
Depressive disorders and alcohol use disorders are widespread among the general population and are significant public health and economic burdens. Alcohol use disorders often co-occur with other psychiatric conditions and this dual diagnosis is called comorbidity. Depressive disorders invariably contribute to the development and worsening of alcohol use disorders, and vice versa. The mechanisms underlying these disorders and their comorbidities remain unclear. Recently, interest in the lateral habenula, a small epithalamic brain structure, has increased because it becomes hyperactive in depression and alcohol use disorders, and can inhibit dopamine and serotonin neurons in the midbrain reward center, the hypofunction of which is believed to be a critical contributor to the etiology of depressive disorders and alcohol use disorders as well as their comorbidities. Additionally, calcium/calmodulin-dependent protein kinase II (CaMKII) in the lateral habenula has emerged as a critical player in the etiology of these comorbidities. This review analyzes the interplay of CaMKII signaling in the lateral habenula associated with depressive disorders and alcohol use disorders, in addition to the often-comorbid nature of these disorders. Although most of the CaMKII signaling pathway's core components have been discovered, much remains to be learned about the biochemical events that propagate and link between depression and alcohol abuse. As the field rapidly advances, it is expected that further understanding of the pathology involved will allow for targeted treatments.
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20
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Abstract
The brain serotonin systems participate in numerous aspects of reward processing, although it remains elusive how exactly serotonin signals regulate neural computation and reward-related behavior. The application of optogenetics and imaging techniques during the last decade has provided many insights. Here, we review recent progress on the organization and physiology of the dorsal raphe serotonin neurons and the relationships between their activity and behavioral functions in the context of reward processing. We also discuss several interesting theories on serotonin's function and how these theories may be reconciled by the possibility that serotonin, acting in synergy with coreleased glutamate, tracks and calculates the so-called beneficialness of the current state to guide an animal's behavior in dynamic environments.
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Affiliation(s)
- Zhixiang Liu
- National Institute of Biological Sciences, Beijing 102206, China
| | - Rui Lin
- National Institute of Biological Sciences, Beijing 102206, China
| | - Minmin Luo
- National Institute of Biological Sciences, Beijing 102206, China
- School of Life Sciences, Tsinghua University, Beijing 100081, China
- Chinese Institute for Brain Research, Beijing 102206, China
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21
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Naturalistic operant responses in deer mice (Peromyscus maniculatus bairdii) and its response to outcome manipulation and serotonergic intervention. Behav Pharmacol 2020; 31:343-358. [DOI: 10.1097/fbp.0000000000000536] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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22
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Gondré-Lewis MC, Bassey R, Blum K. Pre-clinical models of reward deficiency syndrome: A behavioral octopus. Neurosci Biobehav Rev 2020; 115:164-188. [PMID: 32360413 DOI: 10.1016/j.neubiorev.2020.04.021] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 04/08/2020] [Accepted: 04/20/2020] [Indexed: 12/15/2022]
Abstract
Individuals with mood disorders or with addiction, impulsivity and some personality disorders can share in common a dysfunction in how the brain perceives reward, where processing of natural endorphins or the response to exogenous dopamine stimulants is impaired. Reward Deficiency Syndrome (RDS) is a polygenic trait with implications that suggest cross-talk between different neurological systems that include the known reward pathway, neuroendocrine systems, and motivational systems. In this review we evaluate well-characterized animal models for their construct validity and as potential models for RDS. Animal models used to study substance use disorder, major depressive disorder (MDD), early life stress, immune dysregulation, attention deficit hyperactivity disorder (ADHD), post traumatic stress disorder (PTSD), compulsive gambling and compulsive eating disorders are discussed. These disorders recruit underlying reward deficiency mechanisms in multiple brain centers. Because of the widespread and remarkable array of associated/overlapping behavioral manifestations with a common root of hypodopaminergia, the basic endophenotype recognized as RDS is indeed likened to a behavioral octopus. We conclude this review with a look ahead on how these models can be used to investigate potential therapeutics that target the underlying common deficiency.
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Affiliation(s)
- Marjorie C Gondré-Lewis
- Department of Anatomy, Howard University College of Medicine, 520 W Street, NW, Washington D.C., 20059, United States; Developmental Neuropsychopharmacology Laboratory, Howard University College of Medicine, 520 W Street, NW, Washington D.C., 20059, United States.
| | - Rosemary Bassey
- Developmental Neuropsychopharmacology Laboratory, Howard University College of Medicine, 520 W Street, NW, Washington D.C., 20059, United States; Department of Science Education, Donald and Barbara Zucker School of Medicine at Hofstra/ Northwell, 500 Hofstra University, Hempstead, NY 11549, United States
| | - Kenneth Blum
- Western University Health Sciences, Graduate College of Biomedical Sciences, Pomona, California, United States
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23
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Das S, Ooi FK, Cruz Corchado J, Fuller LC, Weiner JA, Prahlad V. Serotonin signaling by maternal neurons upon stress ensures progeny survival. eLife 2020; 9:e55246. [PMID: 32324136 PMCID: PMC7237211 DOI: 10.7554/elife.55246] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 04/22/2020] [Indexed: 01/03/2023] Open
Abstract
Germ cells are vulnerable to stress. Therefore, how organisms protect their future progeny from damage in a fluctuating environment is a fundamental question in biology. We show that in Caenorhabditis elegans, serotonin released by maternal neurons during stress ensures the viability and stress resilience of future offspring. Serotonin acts through a signal transduction pathway conserved between C. elegans and mammalian cells to enable the transcription factor HSF1 to alter chromatin in soon-to-be fertilized germ cells by recruiting the histone chaperone FACT, displacing histones, and initiating protective gene expression. Without serotonin release by maternal neurons, FACT is not recruited by HSF1 in germ cells, transcription occurs but is delayed, and progeny of stressed C. elegans mothers fail to complete development. These studies uncover a novel mechanism by which stress sensing by neurons is coupled to transcription response times of germ cells to protect future offspring.
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Affiliation(s)
- Srijit Das
- Department of Biology, Aging Mind and Brain InitiativeIowa CityUnited States
| | - Felicia K Ooi
- Department of Biology, Aging Mind and Brain InitiativeIowa CityUnited States
| | | | | | - Joshua A Weiner
- Department of BiologyIowa CityUnited States
- Iowa Neuroscience InstituteIowa CityUnited States
| | - Veena Prahlad
- Department of Biology, Aging Mind and Brain InitiativeIowa CityUnited States
- Department of BiologyIowa CityUnited States
- Iowa Neuroscience InstituteIowa CityUnited States
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24
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Cruz-Corchado J, Ooi FK, Das S, Prahlad V. Global Transcriptome Changes That Accompany Alterations in Serotonin Levels in Caenorhabditis elegans. G3 (BETHESDA, MD.) 2020; 10:1225-1246. [PMID: 31996358 PMCID: PMC7144078 DOI: 10.1534/g3.120.401088] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 01/25/2020] [Indexed: 11/18/2022]
Abstract
Serotonin (5-hydroxytryptamine, 5-HT), is a phylogenetically ancient molecule best characterized as a neurotransmitter that modulates multiple aspects of mood and social cognition. The roles that 5-HT plays in normal and abnormal behavior are not fully understood but have been posited to be due to its common function as a 'defense signal'. However, 5-HT levels also systemically impact cell physiology, modulating cell division, migration, apoptosis, mitochondrial biogenesis, cellular metabolism and differentiation. Whether these diverse cellular effects of 5-HT also share a common basis is unclear. C. elegans provides an ideal system to interrogate the systemic effects of 5-HT, since lacking a blood-brain barrier, 5-HT synthesized and released by neurons permeates the organism to modulate neuronal as well as non-neuronal cells throughout the body. Here we used RNA-Seq to characterize the systemic changes in gene expression that occur in C. elegans upon altering 5-HT levels, and compared the transcriptomes to published datasets. We find that an acute increase in 5-HT is accompanied by a global decrease in gene expression levels, upregulation of genes involved in stress pathways, changes that significantly correlate with the published transcriptomes of animals that have activated defense and immune responses, and an increase in levels of phosphorylated eukaryotic initiation factor, eIF2α. In 5-HT deficient animals lacking tryptophan hydroxylase (tph-1(mg280)II) there is a net increase in gene expression, with an overrepresentation of genes related to development and chromatin. Surprisingly, the transcriptomes of animals with acute increases in 5-HT levels, and 5-HT deficiency do not overlap with transcriptomes of mutants with whom they share striking physiological resemblance. These studies are the first to catalog systemic transcriptome changes that occur upon alterations in 5-HT levels. They further show that in C. elegans changes in gene expression upon altering 5-HT levels, and changes in physiology, are not directly correlated.
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Affiliation(s)
- Johnny Cruz-Corchado
- Department of Biology, Aging Mind and Brain Initiative, Iowa Neuroscience Institute, 143 Biology Building, Iowa City, IA 52242-1324
| | - Felicia K Ooi
- Department of Biology, Aging Mind and Brain Initiative, Iowa Neuroscience Institute, 143 Biology Building, Iowa City, IA 52242-1324
| | - Srijit Das
- Department of Biology, Aging Mind and Brain Initiative, Iowa Neuroscience Institute, 143 Biology Building, Iowa City, IA 52242-1324
| | - Veena Prahlad
- Department of Biology, Aging Mind and Brain Initiative, Iowa Neuroscience Institute, 143 Biology Building, Iowa City, IA 52242-1324
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25
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van Staden C, de Brouwer G, Botha TL, Finger-Baier K, Brand SJ, Wolmarans D. Dopaminergic and serotonergic modulation of social reward appraisal in zebrafish (Danio rerio) under circumstances of motivational conflict: Towards a screening test for anti-compulsive drug action. Behav Brain Res 2020; 379:112393. [PMID: 31785362 DOI: 10.1016/j.bbr.2019.112393] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 11/26/2019] [Accepted: 11/26/2019] [Indexed: 01/04/2023]
Abstract
Cognitive flexibility, shown to be impaired in patients presenting with compulsions, is dependent on balanced dopaminergic and serotonergic interaction. Towards the development of a zebrafish (Danio rerio) screening test for anti-compulsive drug action, we manipulated social reward appraisal under different contexts by means of dopaminergic (apomorphine) and serotonergic (escitalopram) intervention. Seven groups of zebrafish (n = 6 per group) were exposed for 24 days (1 h per day) to either control (normal tank water), apomorphine (50 or 100 μg/L), escitalopram (500 or 1000 μg/L) or a combination (A100/E500 or A100/E1000 μg/L). Contextual reward appraisal was assessed over three phases i.e. Phase 1 (contingency association), Phase 2 (dissociative testing), and Phase 3 (re-associative testing). We demonstrate that 1) sight of social conspecifics is an inadequate motivational reinforcer under circumstances of motivational conflict, 2) dopaminergic and serotonergic intervention lessens the importance of an aversive stimulus, increasing the motivational valence of social reward, 3) while serotoninergic intervention maintains reward directed behavior, high-dose dopaminergic intervention bolsters cue-directed responses and 4) high-dose escitalopram reversed apomorphine-induced behavioral inflexibility. The results reported here are supportive of current dopamine-serotonin opponency theories and confirm the zebrafish as a potentially useful species in which to investigate compulsive-like behaviors.
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Affiliation(s)
- C van Staden
- Centre of Excellence for Pharmaceutical Sciences, Department of Pharmacology, North-West University, Potchefstroom, South Africa
| | - G de Brouwer
- Centre of Excellence for Pharmaceutical Sciences, Department of Pharmacology, North-West University, Potchefstroom, South Africa
| | - T L Botha
- Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - K Finger-Baier
- Department Genes - Circuits - Behavior, Max Planck Institute of Neurobiology, Martinsried, Germany
| | - S J Brand
- Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - D Wolmarans
- Centre of Excellence for Pharmaceutical Sciences, Department of Pharmacology, North-West University, Potchefstroom, South Africa.
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26
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Skandali N, Rowe JB, Voon V, Deakin JB, Cardinal RN, Cormack F, Passamonti L, Bevan-Jones WR, Regenthal R, Chamberlain SR, Robbins TW, Sahakian BJ. Dissociable effects of acute SSRI (escitalopram) on executive, learning and emotional functions in healthy humans. Neuropsychopharmacology 2018; 43:2645-2651. [PMID: 30305705 PMCID: PMC6224451 DOI: 10.1038/s41386-018-0229-z] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 08/24/2018] [Accepted: 09/16/2018] [Indexed: 02/02/2023]
Abstract
Serotonin is implicated in multiple executive functions including goal-directed learning, cognitive flexibility, response inhibition and emotional regulation. These functions are impaired in several psychiatric disorders, such as depression and obsessive-compulsive disorder. We tested the cognitive effects of the selective serotonin reuptake inhibitor escitalopram, using an acute and clinically relevant dose (20 mg), in 66 healthy male and female volunteers in a double-blind, placebo-controlled study. Participants performed a cognitive test battery including a probabilistic and reversal learning task, the CANTAB intra-dimensional/extra-dimensional shift test of cognitive flexibility, a response inhibition task with interleaved stop-signal and No-Go trials and tasks measuring emotional processing. We showed that acute escitalopram administration impaired learning and cognitive flexibility, but improved the ability to inhibit responses in stop-signal trials while leaving unaffected acute emotional processing. Our findings suggest a dissociation of effects of acute escitalopram on cognitive functions, possibly mediated by differential modulation of brain serotonin levels in distinct functional neural circuits.
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Affiliation(s)
- Nikolina Skandali
- Department of Psychiatry, University of Cambridge, Cambridge, UK.
- Medical Research Council/Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK.
- Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK.
| | - James B Rowe
- Medical Research Council/Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Valerie Voon
- Department of Psychiatry, University of Cambridge, Cambridge, UK
- Medical Research Council/Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
- Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK
| | - Julia B Deakin
- Department of Psychiatry, University of Cambridge, Cambridge, UK
- Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK
| | - Rudolf N Cardinal
- Department of Psychiatry, University of Cambridge, Cambridge, UK
- Medical Research Council/Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
- Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK
| | | | - Luca Passamonti
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | | | - Ralf Regenthal
- Division of Clinical Pharmacology, Rudolf-Boehm-Institute of Pharmacology and Toxicology, Leipzig University, Medical Faculty, Leipzig, Germany
| | - Samuel R Chamberlain
- Department of Psychiatry, University of Cambridge, Cambridge, UK
- Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK
| | - Trevor W Robbins
- Medical Research Council/Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
- Department of Psychology, University of Cambridge, Cambridge, UK
| | - Barbara J Sahakian
- Department of Psychiatry, University of Cambridge, Cambridge, UK
- Medical Research Council/Wellcome Trust Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
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McNaughton N, Smillie LD. Some Metatheoretical Principles for Personality Neuroscience. PERSONALITY NEUROSCIENCE 2018; 1:e11. [PMID: 32435730 PMCID: PMC7219693 DOI: 10.1017/pen.2018.9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Accepted: 03/05/2018] [Indexed: 12/20/2022]
Abstract
Theories in personality neuroscience must aim to be consistent with several levels of explanation. If we view personality traits as constructs located only at the psychological level, we must still make their explanations compatible with observations and theories at lower levels, particularly with what we know at the neural level. If we view personality traits as constructs located only at the neural level, we will still need to predict their emergent effects at the psychological level. Personality theory at present treats traits as psychological-level constructs, with even the recent neurally oriented Cybernetic Big Five Theory specified in terms of a "conceptual nervous system" and not requiring complete or immediate translation into neural mechanisms. Here, we argue for the existence of phylogenetically old, neural-level traits that are substantially conserved across many vertebrate species. We first ask what known mechanisms control trait-like properties of neural systems: Focusing on hormones, the GABAA receptor, and amine neurotransmitter systems. We derive from what we know about these sources of neuronal modulation some metatheoretical principles to guide the future development of those aspects of personality theory, starting with neural-level trait constructs and drawing implications for higher-level trait psychology observations. Current descriptive approaches such as the Big Five are an essential precursor to personality neuroscience, but may not map one-to-one to the mechanisms and constructs of a neuroscience-based approach to traits.
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Affiliation(s)
- Neil McNaughton
- Department of Psychology and Brain Health Research Centre, University of Otago, Dunedin, New Zealand
| | - Luke D. Smillie
- Melbourne School of Psychological Sciences, The University of Melbourne, Melbourne, Australia
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Abstract
Apathy and anhedonia are common syndromes of motivation that are associated with a wide range of brain disorders and have no established therapies. Research using animal models suggests that a useful framework for understanding motivated behaviour lies in effort-based decision making for reward. The neurobiological mechanisms underpinning such decisions have now begun to be determined in individuals with apathy or anhedonia, providing an important foundation for developing new treatments. The findings suggest that there might be some shared mechanisms between both syndromes. A transdiagnostic approach that cuts across traditional disease boundaries provides a potentially useful means for understanding these conditions.
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Affiliation(s)
- Masud Husain
- Nuffield Department of Clinical Neurosciences and Department of Experimental Psychology, University of Oxford. John Radcliffe Hospital, Oxford, UK.
| | - Jonathan P Roiser
- Institute of Cognitive Neuroscience, University College London, London, UK
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29
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Yang KC, Takano A, Halldin C, Farde L, Finnema SJ. Serotonin concentration enhancers at clinically relevant doses reduce [ 11C]AZ10419369 binding to the 5-HT 1B receptors in the nonhuman primate brain. Transl Psychiatry 2018; 8:132. [PMID: 30013068 PMCID: PMC6048172 DOI: 10.1038/s41398-018-0178-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 02/14/2018] [Accepted: 04/03/2018] [Indexed: 12/25/2022] Open
Abstract
The serotonin (5-HT) system plays an important role in the pathophysiology and treatment of several major psychiatric disorders. Currently, no suitable positron emission tomography (PET) imaging paradigm is available to assess 5-HT release in the living human brain. [11C]AZ10419369 binds to 5-HT1B receptors and is one of the most 5-HT-sensitive radioligands available. This study applied 5-HT concentration enhancers which can be safely studied in humans, and examined their effect on [11C]AZ10419369 binding at clinically relevant doses, including amphetamine (1 mg/kg), 3,4-methylenedioxymethamphetamine (MDMA; 1 mg/kg) or 5-hydroxy-L-tryptophan (5-HTP; 5 mg/kg). Twenty-six PET measurements (14 for amphetamine, 6 for MDMA and 6 for 5-HTP) using a bolus and constant infusion protocol were performed in four cynomolgus monkeys before or after drug administration. Binding potential (BPND) values were determined with the equilibrium method (integral interval: 63-123 min) using cerebellum as the reference region. BPND values were significantly decreased in several examined brain regions after administration of amphetamine (range: 19-31%), MDMA (16-25%) or 5-HTP (13-31%). Reductions in [11C]AZ10419369 binding were greater in striatum than cortical regions after administration of 5-HTP, while no prominent regional differences were found for amphetamine and MDMA. In conclusion, [11C]AZ10419369 binding is sensitive to changes in 5-HT concentration induced by amphetamine, MDMA or 5-HTP. The robust changes in BPND, following pretreatment drugs administered at clinically relevant doses, indicate that the applied PET imaging paradigms hold promise to be successfully used in future human studies.
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Affiliation(s)
- Kai-Chun Yang
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
| | - Akihiro Takano
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Christer Halldin
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Lars Farde
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
- Personalized Health Care and Biomarkers, AstraZeneca PET Science Center at Karolinska Institutet, Stockholm, Sweden
| | - Sjoerd J Finnema
- Department of Clinical Neuroscience, Center for Psychiatric Research, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, USA
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30
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Jean-Richard-Dit-Bressel P, Killcross S, McNally GP. Behavioral and neurobiological mechanisms of punishment: implications for psychiatric disorders. Neuropsychopharmacology 2018; 43:1639-1650. [PMID: 29703994 PMCID: PMC6006171 DOI: 10.1038/s41386-018-0047-3] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 02/27/2018] [Accepted: 03/05/2018] [Indexed: 02/08/2023]
Abstract
Punishment involves learning about the relationship between behavior and its adverse consequences. Punishment is fundamental to reinforcement learning, decision-making and choice, and is disrupted in psychiatric disorders such as addiction, depression, and psychopathy. However, little is known about the brain mechanisms of punishment and much of what is known is derived from study of superficially similar, but fundamentally distinct, forms of aversive learning such as fear conditioning and avoidance learning. Here we outline the unique conditions that support punishment, the contents of its learning, and its behavioral consequences. We consider evidence implicating GABA and monoamine neurotransmitter systems, as well as corticostriatal, amygdala, and dopamine circuits in punishment. We show how maladaptive punishment processes are implicated in addictions, impulse control disorders, psychopathy, anxiety, and depression and argue that a better understanding of the cellular, circuit, and cognitive mechanisms of punishment will make important contributions to next generation therapeutic approaches.
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31
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Neukam PT, Kroemer NB, Deza Araujo YI, Hellrung L, Pooseh S, Rietschel M, Witt SH, Schwarzenbolz U, Henle T, Smolka MN. Risk-seeking for losses is associated with 5-HTTLPR, but not with transient changes in 5-HT levels. Psychopharmacology (Berl) 2018; 235:2151-2165. [PMID: 29730700 DOI: 10.1007/s00213-018-4913-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 04/17/2018] [Indexed: 10/17/2022]
Abstract
RATIONALE Serotonin (5-HT) plays a key role in different aspects of value-based decision-making. A recent framework proposed that tonic 5-HT (together with dopamine, DA) codes future average reward expectations, providing a baseline against which possible choice outcomes are compared to guide decision-making. OBJECTIVES To test whether high 5-HT levels decrease loss aversion, risk-seeking for gains, and risk-seeking for losses. METHODS In a first session, 611 participants were genotyped for 5-HTTLPR and performed a mixed gambles (MGA) task and two probability discounting tasks for gains and losses, respectively (PDG/PDL). Afterwards, a subsample of 105 participants (44 with S/S, 6 with S/L, 55 with L/L genotype) completed the pharmacological study using a crossover design with tryptophan depletion (ATD), loading (ATL), and balanced (BAL) conditions. The same decision constructs were assessed. RESULTS We found increased risk-seeking for losses in S/S compared to L/L individuals at the first visit (p = 0.002). Neither tryptophan depletion nor loading affected decision-making, nor did we observe an interaction between intervention and 5-HTTLPR genotype. CONCLUSION Our data do not support the idea that transient changes of tonic 5-HT affect value-based decision-making. We provide evidence for an association of 5-HTTLPR with risk-seeking for losses, independent of acute 5-HT levels. This indicates that the association of 5-HTTLPR and risk-seeking for losses is mediated via other mechanisms, possibly by differences in the structural development of neural circuits of the 5-HT system during early life phases.
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Affiliation(s)
- Philipp T Neukam
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Nils B Kroemer
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany.,Department of Psychiatry and Psychotherapy, University of Tübingen, Tübingen, Germany
| | - Yacila I Deza Araujo
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Lydia Hellrung
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany.,Department of Economics, University of Zürich, Zürich, Switzerland
| | - Shakoor Pooseh
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany
| | - Marcella Rietschel
- Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Stephanie H Witt
- Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Uwe Schwarzenbolz
- Institute of Food Chemistry, Technische Universität Dresden, Dresden, Germany
| | - Thomas Henle
- Institute of Food Chemistry, Technische Universität Dresden, Dresden, Germany
| | - Michael N Smolka
- Department of Psychiatry and Neuroimaging Center, Technische Universität Dresden, Dresden, Germany.
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32
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Faulkner P, Ghahremani DG, Tyndale RF, Hellemann G, London ED. Functional Connectivity of the Raphe Nuclei: Link to Tobacco Withdrawal in Smokers. Int J Neuropsychopharmacol 2018; 21:800-808. [PMID: 29924326 PMCID: PMC6119292 DOI: 10.1093/ijnp/pyy054] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 06/18/2018] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Although nicotine alters serotonergic neurochemistry, clinical trials of serotonergic medications for smoking cessation have provided mixed results. Understanding the role of serotonergic dysfunction in tobacco use disorder may advance development of novel pharmacotherapies. METHODS Functional magnetic resonance imaging was used to measure resting-state functional connectivity of the raphe nuclei as an indicator of serotonergic function. Connectivity of the dorsal and median raphe nuclei was compared between 18 young smokers (briefly abstinent, ~40 minutes post-smoking) and 19 young nonsmokers (16-21 years old); connectivity was also examined in a separate sample of overnight-abstinent smokers (18-25 years old), before and after smoking the first cigarette of the day. Relationships between connectivity of the raphe nuclei with psychological withdrawal and craving were tested in smokers. RESULTS Connectivity of the median raphe nucleus with the right hippocampal complex was weaker in smokers than in nonsmokers and was negatively correlated with psychological withdrawal in smokers. In overnight-abstinent smokers, smoking increased connectivity of the median raphe nucleus with the right hippocampal complex, and the increase was positively correlated with the decrease in psychological withdrawal. CONCLUSIONS Relief of withdrawal due to smoking is potentially linked to the serotonergic pathway that includes the median raphe nucleus and hippocampal complex. These results suggest that serotonergic medications may be especially beneficial for smokers who endorse strong psychological withdrawal during abstinence from smoking.
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Affiliation(s)
- Paul Faulkner
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, California
| | - Dara G Ghahremani
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, California
| | - Rachel F Tyndale
- Department of Pharmacology and Toxicology, and Department of Psychiatry, University of Toronto, Toronto, ON, Canada,Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Gerhard Hellemann
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, California
| | - Edythe D London
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, California,Department of Molecular and Medical Pharmacology, University of California, Los Angeles, California,The Brain Research Institute, University of California, Los Angeles, California,Correspondence: Edythe D. London, PhD, Semel Institute, University of California, Los Angeles, 760 Westwood Plaza, Los Angeles, CA 90095 ()
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33
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Shah R, Courtiol E, Castellanos FX, Teixeira CM. Abnormal Serotonin Levels During Perinatal Development Lead to Behavioral Deficits in Adulthood. Front Behav Neurosci 2018; 12:114. [PMID: 29928194 PMCID: PMC5997829 DOI: 10.3389/fnbeh.2018.00114] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 05/17/2018] [Indexed: 11/18/2022] Open
Abstract
Serotonin (5-HT) is one of the best-studied modulatory neurotransmitters with ubiquitous presynaptic release and postsynaptic reception. 5-HT has been implicated in a wide variety of brain functions, ranging from autonomic regulation, sensory perception, feeding and motor function to emotional regulation and cognition. The role of this neuromodulator in neuropsychiatric diseases is unquestionable with important neuropsychiatric medications, e.g., most antidepressants, targeting this system. Importantly, 5-HT modulates neurodevelopment and changes in its levels during development can have life-long consequences. In this mini-review, we highlight that exposure to both low and high serotonin levels during the perinatal period can lead to behavioral deficits in adulthood. We focus on three exogenous factors that can change 5-HT levels during the critical perinatal period: dietary tryptophan depletion, exposure to serotonin-selective-reuptake-inhibitors (SSRIs) and poor early life care. We discuss the effects of each of these on behavioral deficits in adulthood.
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Affiliation(s)
- Relish Shah
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, United States
| | - Emmanuelle Courtiol
- CNRS UMR 5292 - INSERM U1028, Lyon Neuroscience Research Center, Université Lyon 1, Lyon, France
| | - Francisco X Castellanos
- Department of Child and Adolescent Psychiatry, Hassenfeld Children's Hospital at NYU Langone, New York, NY, United States.,Division of Clinical Research, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, United States
| | - Catia M Teixeira
- Emotional Brain Institute, Nathan Kline Institute for Psychiatric Research, Orangeburg, NY, United States.,Department of Child and Adolescent Psychiatry, Hassenfeld Children's Hospital at NYU Langone, New York, NY, United States
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34
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Fakhoury M. The dorsal diencephalic conduction system in reward processing: Spotlight on the anatomy and functions of the habenular complex. Behav Brain Res 2018; 348:115-126. [PMID: 29684476 DOI: 10.1016/j.bbr.2018.04.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Revised: 03/16/2018] [Accepted: 04/13/2018] [Indexed: 12/21/2022]
Abstract
The dorsal diencephalic conduction system (DDC) is a highly conserved pathway in vertebrates that provides a route for the neural information to flow from forebrain to midbrain structures. It contains the bilaterally paired habenular nuclei along with two fiber tracts, the stria medullaris and the fasciculus retroflexus. The habenula is the principal player in mediating the dialogue between forebrain and midbrain regions, and functional abnormalities in this structure have often been attributed to pathologies like mood disorders and substance use disorder. Following Matsumoto and Hikosaka seminal work on the lateral habenula as a source of negative reward signals, the last decade has witnessed a great surge of interest in the role of the DDC in reward-related processes. However, despite significant progress in research, much work remains to unfold the behavioral functions of this intriguing, yet complex, pathway. This review describes the current state of knowledge on the DDC with respect to its anatomy, connectivity, and functions in reward and aversion processes.
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Affiliation(s)
- Marc Fakhoury
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, Quebec, H3C3J7, Canada.
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35
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Rincón-Pérez I, Sánchez-Carmona AJ, Albert J, Hinojosa JA. The association of monoamine-related gene polymorphisms with behavioural correlates of response inhibition: A meta-analytic review. Neurosci Biobehav Rev 2018; 84:49-62. [DOI: 10.1016/j.neubiorev.2017.11.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 10/05/2017] [Accepted: 11/15/2017] [Indexed: 12/23/2022]
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36
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Higgs S, Spetter MS, Thomas JM, Rotshtein P, Lee M, Hallschmid M, Dourish CT. Interactions between metabolic, reward and cognitive processes in appetite control: Implications for novel weight management therapies. J Psychopharmacol 2017; 31:1460-1474. [PMID: 29072515 PMCID: PMC5700796 DOI: 10.1177/0269881117736917] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Traditional models of appetite control have emphasised the role of parallel homeostatic and hedonic systems, but more recently the distinction between independent homeostatic and hedonic systems has been abandoned in favour of a framework that emphasises the cross talk between the neurochemical substrates of the two systems. In addition, evidence has emerged more recently, that higher level cognitive functions such as learning, memory and attention play an important role in everyday appetite control and that homeostatic signals also play a role in cognition. Here, we review this evidence and present a comprehensive model of the control of appetite that integrates cognitive, homeostatic and reward mechanisms. We discuss the implications of this model for understanding the factors that may contribute to disordered patterns of eating and suggest opportunities for developing more effective treatment approaches for eating disorders and weight management.
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Affiliation(s)
- Suzanne Higgs
- 1 School of Psychology, University of Birmingham, Birmingham, UK
| | | | - Jason M Thomas
- 2 Department of Psychology, Aston University, Birmingham, UK
| | - Pia Rotshtein
- 1 School of Psychology, University of Birmingham, Birmingham, UK
| | - Michelle Lee
- 3 Department of Psychology, Swansea University, Swansea, UK
| | - Manfred Hallschmid
- 4 Institute for Medical Psychology and Behavioural Neurobiology, University Tübingen, Tübingen, Germany
- 6 Institute for Diabetes Research and Metabolic Diseases, University of Tübingen, Tübingen, Germany
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da Cunha-Bang S, Hjordt LV, Dam VH, Stenbæk DS, Sestoft D, Knudsen GM. Anterior cingulate serotonin 1B receptor binding is associated with emotional response inhibition. J Psychiatr Res 2017; 92:199-204. [PMID: 28502766 DOI: 10.1016/j.jpsychires.2017.05.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Revised: 05/02/2017] [Accepted: 05/05/2017] [Indexed: 01/10/2023]
Abstract
Serotonin has a well-established role in emotional processing and is a key neurotransmitter in impulsive aggression, presumably by facilitating response inhibition and regulating subcortical reactivity to aversive stimuli. In this study 44 men, of whom 19 were violent offenders and 25 were non-offender controls, completed an emotional Go/NoGo task requiring inhibition of prepotent motor responses to emotional facial expressions. We also measured cerebral serotonin 1B receptor (5-HT1BR) binding with [11C]AZ10419369 positron emission tomography within regions of the frontal cortex. We hypothesized that 5-HT1BR would be positively associated with false alarms (failures to inhibit nogo responses) in the context of aversive (angry and fearful) facial expressions. Across groups, we found that frontal cortex 5-HT1BR binding was positively correlated with false alarms when angry faces were go stimuli and neutral faces were nogo stimuli (p = 0.05, corrected alpha = 0.0125), but not with false alarms for non-emotional stimuli (failures to inhibit geometric figures). A posthoc analysis revealed the strongest association in anterior cingulate cortex (p = 0.006). In summary, 5-HT1BRs in the anterior cingulate are involved in withholding a prepotent response in the context of angry faces. Our findings suggest that serotonin modulates response inhibition in the context of certain emotional stimuli.
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Affiliation(s)
- Sofi da Cunha-Bang
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, DK-2100, Denmark
| | - Liv Vadskjær Hjordt
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, DK-2100, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen, Denmark
| | - Vibeke Høyrup Dam
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, DK-2100, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen, Denmark
| | - Dea Siggaard Stenbæk
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, DK-2100, Denmark
| | - Dorte Sestoft
- Ministry of Justice, Clinic of Forensic Psychiatry, Blegdamsvej 6B, DK-2200 Copenhagen, Denmark
| | - Gitte M Knudsen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, DK-2100, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen, Denmark.
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Dalkner N, Platzer M, Bengesser SA, Birner A, Fellendorf FT, Queissner R, Painold A, Mangge H, Fuchs D, Reininghaus B, Kapfhammer HP, Holasek SJ, Reininghaus EZ. The role of tryptophan metabolism and food craving in the relationship between obesity and bipolar disorder. Clin Nutr 2017; 37:1744-1751. [PMID: 28712531 DOI: 10.1016/j.clnu.2017.06.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 06/22/2017] [Accepted: 06/25/2017] [Indexed: 10/19/2022]
Abstract
BACKGROUND & AIMS Individuals with bipolar disorder (BD) have a significantly increased risk of obesity-related conditions. The imbalance between food intake and energy expenditure is assumed to be a major risk factor for obesity in BD. This study analyzed food craving in relation to anthropometric, metabolic, and neurobiological parameters in a well-characterized cohort of euthymic individuals with BD. METHODS One-hundred-thirty-five patients completed the Food-Craving Inventory assessing four categories of food craving (fat, fast-food, sweets and carbohydrate craving). Additionally, clinical, metabolic and anthropometric parameters were assessed. RESULTS Higher levels of fat craving were observed in males, versus females, with BD. High levels of carbohydrate craving positively correlated with kynurenine and the kynurenine-to-tryptophan ratio. Higher serum nitrite and neopterin levels were related to fat craving. Parameters of fat metabolism (triglycerides, high-density lipoprotein) were associated with fat and fast-food craving. Anthropometric measures of obesity (e.g. body mass index, waist-to-hip-ratio) were not related to food craving. CONCLUSIONS Overweight/obese individuals with BD show an increased driving of tryptophan down the kynurenine pathways, as indicated by an increase in the serum kynurenine-to-tryptophan ratio. The driving of tryptophan down the kynurenine pathway is mediated by immune-inflammatory activity and stress. The correlation of increased kynurenine with food craving, especially carbohydrate craving, probably indicates a regulatory deficit in the maintenance of chronic inflammatory processes in obesity and BD. Food craving seems to be of clinical importance in the treatment of metabolic disturbances in BD, although not associated with anthropometric measures of obesity. Rather, food craving correlates with blood metabolic parameters and an increased activation of the kynurenine pathway, both of which are linked to higher affective symptomatology and the development of cardiovascular diseases.
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Affiliation(s)
- N Dalkner
- Department of Psychiatry, Medical University Graz, Austria
| | - M Platzer
- Department of Psychiatry, Medical University Graz, Austria.
| | - S A Bengesser
- Department of Psychiatry, Medical University Graz, Austria
| | - A Birner
- Department of Psychiatry, Medical University Graz, Austria
| | - F T Fellendorf
- Department of Psychiatry, Medical University Graz, Austria
| | - R Queissner
- Department of Psychiatry, Medical University Graz, Austria
| | - A Painold
- Department of Psychiatry, Medical University Graz, Austria
| | - H Mangge
- Research Unit on Lifestyle and Inflammation-associated Risk Biomarkers, Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University Graz, Austria
| | - D Fuchs
- Division of Biological Chemistry, Biocenter, Medical University of Innsbruck, Austria
| | - B Reininghaus
- Therapiezentrum Justuspark, Versicherungsanstalt öffentlich Bediensteter, Bad Hall, Austria
| | - H P Kapfhammer
- Department of Psychiatry, Medical University Graz, Austria
| | - S J Holasek
- Department of Pathophysiology and Immunology, Medical University Graz, Austria
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Tryptophan depletion affects compulsive behaviour in rats: strain dependent effects and associated neuromechanisms. Psychopharmacology (Berl) 2017; 234:1223-1236. [PMID: 28280881 PMCID: PMC5362668 DOI: 10.1007/s00213-017-4561-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Accepted: 02/02/2017] [Indexed: 02/02/2023]
Abstract
RATIONALE Compulsive behaviour, present in different psychiatric disorders, such as obsessive-compulsive disorder, schizophrenia and drug abuse, is associated with altered levels of monoamines, particularly serotonin (5-hydroxytryptamine) and its receptor system. OBJECTIVES The present study investigated whether 5-HT manipulation, through a tryptophan (TRP) depletion by diet in Wistar and Lister Hooded rats, modulates compulsive drinking in schedule-induced polydipsia (SIP) and locomotor activity in the open-field test. The levels of dopamine, noradrenaline, serotonin and its metabolite were evaluated, as well as the 5-HT2A and 5-HT1A receptor binding, in different brain regions. METHODS Wistar rats were selected as high (HD) or low (LD) drinkers according to their SIP behaviour, while Lister hooded rats did not show SIP acquisition. Both strains were fed for 14 days with either a TRP-free diet (T-) or a TRP-supplemented diet (T+) RESULTS: The TRP depletion diet effectively reduced 5-HT levels in the frontal cortex, amygdala and hippocampus in both strains of rats. The TRP-depleted HD Wistar rats were more sensitive to 5-HT manipulation, exhibiting more licks on SIP than did the non-depleted HD Wistar rats, while the LD Wistar and the Lister Hooded rats did not exhibit differences in SIP. In contrast, the TRP-depleted Lister Hooded rats increased locomotor activity compared to the non-depleted rats, while no differences were found in the Wistar rats. Serotonin 2A receptor binding in the striatum was significantly reduced in the TRP-depleted HD Wistar rats. CONCLUSIONS These results suggest that alterations of the serotonergic system could be involved in compulsive behaviour in vulnerable populations.
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Meyniel F, Goodwin GM, Deakin JW, Klinge C, MacFadyen C, Milligan H, Mullings E, Pessiglione M, Gaillard R. A specific role for serotonin in overcoming effort cost. eLife 2016; 5. [PMID: 27824554 PMCID: PMC5100997 DOI: 10.7554/elife.17282] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 10/05/2016] [Indexed: 02/06/2023] Open
Abstract
Serotonin is implicated in many aspects of behavioral regulation. Theoretical attempts to unify the multiple roles assigned to serotonin proposed that it regulates the impact of costs, such as delay or punishment, on action selection. Here, we show that serotonin also regulates other types of action costs such as effort. We compared behavioral performance in 58 healthy humans treated during 8 weeks with either placebo or the selective serotonin reuptake inhibitor escitalopram. The task involved trading handgrip force production against monetary benefits. Participants in the escitalopram group produced more effort and thereby achieved a higher payoff. Crucially, our computational analysis showed that this effect was underpinned by a specific reduction of effort cost, and not by any change in the weight of monetary incentives. This specific computational effect sheds new light on the physiological role of serotonin in behavioral regulation and on the clinical effect of drugs for depression. CLINICAL TRIAL REGISTRATION ISRCTN75872983.
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Affiliation(s)
- Florent Meyniel
- Motivation, Brain and Behavior team, Institut du Cerveau et de la Moelle épinière, Groupe Hospitalier Pitié-Salpêtrière, Paris, France.,INSERM UMRS 1127, CNRS UMR 7225, Université Pierre et Marie Curie (UPMC-P6), Paris, France.,Cognitive Neuroimaging Unit, NeuroSpin Center, INSERM U992, Institut d'Imagerie Biomédicale, Direction de la recherche fondamentale, Commissariat à l'énergie atomique et aux énergies alternatives, Gif-sur-Yvette, France
| | - Guy M Goodwin
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom.,Warneford Hospital, University of Oxford, Oxford, United Kingdom
| | - Jf William Deakin
- Neuroscience and Psychiatry Unit, The University of Manchester, Manchester, United Kingdom
| | - Corinna Klinge
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom.,Warneford Hospital, University of Oxford, Oxford, United Kingdom
| | - Christine MacFadyen
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom.,Warneford Hospital, University of Oxford, Oxford, United Kingdom
| | - Holly Milligan
- Neuroscience and Psychiatry Unit, The University of Manchester, Manchester, United Kingdom
| | - Emma Mullings
- Neuroscience and Psychiatry Unit, The University of Manchester, Manchester, United Kingdom
| | - Mathias Pessiglione
- Motivation, Brain and Behavior team, Institut du Cerveau et de la Moelle épinière, Groupe Hospitalier Pitié-Salpêtrière, Paris, France.,INSERM UMRS 1127, CNRS UMR 7225, Université Pierre et Marie Curie (UPMC-P6), Paris, France
| | - Raphaël Gaillard
- Centre Hospitalier Sainte-Anne, Service de Psychiatrie, Paris, France.,Faculté de Médecine Paris Descartes, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Laboratoire de Physiopathologie des maladies Psychiatriques, Centre de Psychiatrie et Neurosciences, INSERM U894, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Human Histopathology and Animal Models, Department of Infection and Epidemiology, Institut Pasteur, Paris, France
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Tchenio A, Valentinova K, Mameli M. Can the Lateral Habenula Crack the Serotonin Code? Front Synaptic Neurosci 2016; 8:34. [PMID: 27822183 PMCID: PMC5075531 DOI: 10.3389/fnsyn.2016.00034] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 10/04/2016] [Indexed: 11/13/2022] Open
Abstract
The lateral habenula (LHb) and the serotonergic system both contribute to motivational states by encoding rewarding and aversive signals. Converging evidence suggests that perturbation of these systems is critical for the pathophysiology of mood disorders. Anatomical and functional studies indicate that the serotonergic system and the LHb are interconnected in a forward-feedback loop. However, how serotonin release modifies the synaptic and cellular properties of LHb neurons and whether this has any behavioral repercussions remain poorly investigated. In this review article, we discuss insights gained from rodents and humans regarding the implications of the serotonin system and the LHb in aversion encoding and related disorders. We then describe the type, properties and pharmacology of serotonergic receptors expressed throughout the LHb. Finally, we discuss physiological data reporting how serotonergic signaling modifies synaptic transmission and neuronal activity within the LHb. Altogether, we combine a mechanistic- and circuit-level knowledge to provide an overview on how the LHb integrates serotonergic signals, a process potentially contributing to LHb-dependent encoding of valenced external stimuli.
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Affiliation(s)
- Anna Tchenio
- Institut du Fer à MoulinParis, France; Institut National de la Santé et de la Recherche Médicale (INSERM), UMR-S 839Paris, France; Université Pierre et Marie CurieParis, France
| | - Kristina Valentinova
- Institut du Fer à MoulinParis, France; Institut National de la Santé et de la Recherche Médicale (INSERM), UMR-S 839Paris, France; Université Pierre et Marie CurieParis, France
| | - Manuel Mameli
- Institut du Fer à MoulinParis, France; Institut National de la Santé et de la Recherche Médicale (INSERM), UMR-S 839Paris, France; Université Pierre et Marie CurieParis, France
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42
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Faulkner P, Mancinelli F, Lockwood PL, Matarin M, Dolan RJ, Wood NW, Dayan P, Roiser JP. Peripheral Serotonin 1B Receptor Transcription Predicts the Effect of Acute Tryptophan Depletion on Risky Decision-Making. Int J Neuropsychopharmacol 2016; 20:58-66. [PMID: 27638901 PMCID: PMC5480594 DOI: 10.1093/ijnp/pyw075] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 08/13/2016] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The effects of acute tryptophan depletion on human decision-making suggest that serotonin modulates the processing of rewards and punishments. However, few studies have assessed which of the many types of serotonin receptors are responsible. METHODS Using a within-subject, double-blind, sham-controlled design in 26 subjects, we examined whether individual differences in serotonin system gene transcription, measured in peripheral blood, predicted the effect of acute tryptophan depletion on decision-making. Participants performed a task in which they chose between successive pairs of fixed, lower-stakes (control) and variable, higher-stakes (experimental) gambles, each involving wins or losses. In 21 participants, mRNA from 9 serotonin system genes was measured in whole blood prior to acute tryptophan depletion: 5-HT1B, 5-HT1F, 5-HT2A, 5-HT2B, 5-HT3A, 5-HT3E, 5-HT7 (serotonin receptors), 5-HTT (the serotonin transporter), and tryptophan hydroxylase 1. RESULTS Acute tryptophan depletion did not significantly influence participants' sensitivity to probability, wins, or losses, although there was a trend for a lower tendency to choose experimental gambles overall following depletion. Significant positive correlations, which survived correction for multiple comparisons, were detected between baseline 5-HT1B mRNA levels and acute tryptophan depletion-induced increases in both the overall tendency to choose the experimental gamble and sensitivity to wins. No significant relationship was observed with any other peripheral serotonin system markers. Computational analyses of decision-making data provided results consistent with these findings. CONCLUSIONS These results suggest that the 5-HT1B receptor may modulate the effects of acute tryptophan depletion on risky decision-making. Peripheral levels of serotonin markers may predict response to treatments that act upon the serotonin system, such as selective serotonin reuptake inhibitors.
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Affiliation(s)
- Paul Faulkner
- Institute of Cognitive Neuroscience, University College London, London, United Kingdom (Drs Faulkner and Roiser); Psychiatry and Biobehavioral Sciences, Semel Institute, University of California, Los Angeles, California (Dr Faulkner);,Correspondence: Paul Faulkner, PhD, Semel Institute, 760 Westwood Boulevard, University of California, Los Angeles, CA 90025 ()
| | - Federico Mancinelli
- Institute of Cognitive Neuroscience, University College London, London, United Kingdom (Drs Faulkner and Roiser); Psychiatry and Biobehavioral Sciences, Semel Institute, University of California, Los Angeles, California (Dr Faulkner)
| | - Patricia L Lockwood
- Institute of Cognitive Neuroscience, University College London, London, United Kingdom (Drs Faulkner and Roiser); Psychiatry and Biobehavioral Sciences, Semel Institute, University of California, Los Angeles, California (Dr Faulkner)
| | - Mar Matarin
- Institute of Cognitive Neuroscience, University College London, London, United Kingdom (Drs Faulkner and Roiser); Psychiatry and Biobehavioral Sciences, Semel Institute, University of California, Los Angeles, California (Dr Faulkner)
| | - Raymond J Dolan
- Institute of Cognitive Neuroscience, University College London, London, United Kingdom (Drs Faulkner and Roiser); Psychiatry and Biobehavioral Sciences, Semel Institute, University of California, Los Angeles, California (Dr Faulkner)
| | - Nick W Wood
- Institute of Cognitive Neuroscience, University College London, London, United Kingdom (Drs Faulkner and Roiser); Psychiatry and Biobehavioral Sciences, Semel Institute, University of California, Los Angeles, California (Dr Faulkner)
| | - Peter Dayan
- Institute of Cognitive Neuroscience, University College London, London, United Kingdom (Drs Faulkner and Roiser); Psychiatry and Biobehavioral Sciences, Semel Institute, University of California, Los Angeles, California (Dr Faulkner)
| | - Jonathan P Roiser
- Gatsby Computational Neuroscience Unit (Mr Mancinelli and Dr Dayan), and CoMPLEX Centre for Mathematics, Physics and Engineering in the Life Sciences and Experimental Biology (Mr Mancinelli), University College London, London, United Kingdom; Experimental Psychology, University of Oxford, Oxford, United Kingdom (Dr Lockwood); Clinical and Experimental Epilepsy, Institute of Neurology (Dr Matarin), and Wellcome Trust Centre for Neuroimaging (Dr Dolan), University College London, London, United Kingdom; Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, United Kingdom (Dr Wood)
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43
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Gillan CM, Robbins TW, Sahakian BJ, van den Heuvel OA, van Wingen G. The role of habit in compulsivity. Eur Neuropsychopharmacol 2016; 26:828-40. [PMID: 26774661 PMCID: PMC4894125 DOI: 10.1016/j.euroneuro.2015.12.033] [Citation(s) in RCA: 134] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 12/17/2015] [Accepted: 12/20/2015] [Indexed: 11/22/2022]
Abstract
Compulsivity has been recently characterized as a manifestation of an imbalance between the brain׳s goal-directed and habit-learning systems. Habits are perhaps the most fundamental building block of animal learning, and it is therefore unsurprising that there are multiple ways in which the development and execution of habits can be promoted/discouraged. Delineating these neurocognitive routes may be critical to understanding if and how habits contribute to the many faces of compulsivity observed across a range of psychiatric disorders. In this review, we distinguish the contribution of excessive stimulus-response habit learning from that of deficient goal-directed control over action and response inhibition, and discuss the role of stress and anxiety as likely contributors to the transition from goal-directed action to habit. To this end, behavioural, pharmacological, neurobiological and clinical evidence are synthesised and a hypothesis is formulated to capture how habits fit into a model of compulsivity as a trans-diagnostic psychiatric trait.
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Affiliation(s)
- Claire M Gillan
- Department of Psychology, New York University, 6 Washington Place, New York, NY 10003, USA; Department of Psychology, University of Cambridge, Cambridge, United Kingdom; Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, United Kingdom.
| | - Trevor W Robbins
- Department of Psychology, University of Cambridge, Cambridge, United Kingdom; Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, United Kingdom
| | - Barbara J Sahakian
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, United Kingdom; Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom
| | - Odile A van den Heuvel
- Department of Psychiatry, VU University Medical Center, Amsterdam, The Netherlands; Department of Anatomy & Neurosciences, VU University Medical Center, Amsterdam, The Netherlands; The OCD Team, Haukeland University Hospital, Bergen, Norway
| | - Guido van Wingen
- Department of Psychiatry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Lochner C, Chamberlain SR, Kidd M, Fineberg NA, Stein DJ. Altered cognitive response to serotonin challenge as a candidate endophenotype for obsessive-compulsive disorder. Psychopharmacology (Berl) 2016; 233:883-91. [PMID: 26645225 DOI: 10.1007/s00213-015-4172-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 11/21/2015] [Indexed: 11/26/2022]
Abstract
RATIONALE Obsessive-compulsive disorder (OCD) implicates dysfunction of orbitofrontal and insula-related circuitry and of the serotonin system. There is an on-going search in psychiatry for intermediate biological markers, termed 'endophenotypes', that exist not only in patients with a given disorder but also in their clinically unaffected first-degree relatives. OBJECTIVE Pharmacological challenge is recognized as a means of eliciting an endophenotype, but this strategy has yet to be used in OCD. METHODS Twenty-three OCD patients without comorbidities (12 [52.2 %] female), 13 clinically asymptomatic first-degree relatives of OCD patients (11 [84.6 %] female) and 27 healthy controls (16 [59.3 %] female) received single-dose escitalopram (20 mg) and placebo in a randomized double-blind crossover design. Effects of treatment on decision-making were quantified using the Cambridge Gamble Task (CGT) in conjunction with a mixed model analysis of covariance (ANCOVA). RESULTS There was a significant interaction between serotonergic challenge and group for risk adjustment on the CGT (F = 4.1406; p = 0.02). Only controls showed a significant placebo-drug change in risk adjustment (p = 0.02; versus p > 0.10). Numerically, escitalopram was associated with increase in risk adjustment in controls and reductions in the other groups. Change in risk adjustment was similar in OCD patients and relatives (p = 0.806) and differed significantly from controls (p = 0.007; p = 0.041, respectively). CONCLUSIONS Individuals with OCD, and first-degree relatives, showed an altered cognitive response to serotonin challenge. This is the first demonstration of a candidate pharmacological challenge endophenotype for the disorder. Future work should confirm these findings in a larger sample size and ideally extend them to other cognitive paradigms, utilizing functional neuroimaging.
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Affiliation(s)
- Christine Lochner
- US/UCT MRC Unit on Anxiety & Stress Disorders, Department of Psychiatry, University of Stellenbosch, PO Box 241, Cape Town, 8000, South Africa.
| | - Samuel R Chamberlain
- Department of Psychiatry, University of Cambridge School of Clinical Medicine and Cambridge and Peterborough NHS Foundation Trust (CPFT), Cambridge, UK
| | - Martin Kidd
- Centre for Statistical Consultation, Department of Statistics and Actuarial Sciences, University of Stellenbosch, Stellenbosch, South Africa
| | - Naomi A Fineberg
- Department of Psychiatry, University of Cambridge School of Clinical Medicine and Cambridge and Peterborough NHS Foundation Trust (CPFT), Cambridge, UK
- Hertfordshire Partnership University NHS Foundation Trust and University Of Hertfordshire, Hatfield, UK
| | - Dan J Stein
- US/UCT MRC Unit on Anxiety & Stress Disorders, Department of Psychiatry and Mental Health, University of Cape Town, Cape Town, South Africa
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Miendlarzewska EA, Bavelier D, Schwartz S. Influence of reward motivation on human declarative memory. Neurosci Biobehav Rev 2016; 61:156-76. [DOI: 10.1016/j.neubiorev.2015.11.015] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 10/13/2015] [Accepted: 11/28/2015] [Indexed: 12/13/2022]
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Johnston BA, Tolomeo S, Gradin V, Christmas D, Matthews K, Steele JD. Failure of hippocampal deactivation during loss events in treatment-resistant depression. Brain 2015; 138:2766-76. [PMID: 26133661 DOI: 10.1093/brain/awv177] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 04/21/2015] [Indexed: 12/18/2022] Open
Abstract
Major depressive disorder is characterized by anhedonia, cognitive biases, ruminations, hopelessness and increased anxiety. Blunted responses to rewards have been reported in a number of recent neuroimaging and behavioural studies of major depressive disorder. In contrast, neural responses to aversive events remain an under-studied area. While selective serotonergic reuptake inhibitors are often effective in treating major depressive disorder, their mechanism of action remains unclear. Following a series of animal model investigations of depressive illness and serotonergic function, Deakin and Graeff predicted that brain activity in patients with major depressive disorder is associated with an overactive dorsal raphe nucleus with overactive projections to the amygdala, periaqueductal grey and striatum, and an underactive median raphe nucleus with underactive projections to the hippocampus. Here we describe an instrumental loss-avoidance and win-gain reinforcement learning functional magnetic resonance imaging study with 40 patients with highly treatment-resistant major depressive disorder and never-depressed controls. The dorsal raphe nucleus/ periaqueductal grey region of the midbrain and hippocampus were found to be overactive in major depressive disorder during unsuccessful loss-avoidance although the median raphe nucleus was not found to be underactive. Hippocampal overactivity was due to a failure to deactivate during loss events in comparison to controls, and hippocampal over-activity correlated with depression severity, self-report 'hopelessness' and anxiety. Deakin and Graeff argued that the median raphe nucleus normally acts to inhibit consolidation of aversive memories via the hippocampus and this system is underactive in major depressive disorder, facilitating the development of ruminations, while the dorsal raphe nucleus system is engaged by distal cues predictive of threats and is overactive in major depressive disorder. During win events the striatum was underactive in major depressive disorder. We tested individual patient consistency of these findings using within-study replication. Abnormal hippocampal activity correctly predicted individual patient diagnostic status in 97% (sensitivity 95%, specificity 100%) of subjects, and abnormal striatal activity predicted diagnostic status in 84% (sensitivity 79%, specificity 89%) of subjects. We conclude that the neuroimaging findings were largely consistent with Deaken and Graeff's predictions, abnormally increased hippocampal activity during loss events was an especially consistent abnormality, and brainstem serotonergic nuclei merit further study in depressive illness.
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Affiliation(s)
- Blair A Johnston
- 1 Division of Neuroscience, Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, U.K, DD1 9SY
| | - Serenella Tolomeo
- 1 Division of Neuroscience, Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, U.K, DD1 9SY
| | - Victoria Gradin
- 2 CIBPsi, Faculty of Psychology, Universidad de al República, Montevideo, Uruguay
| | - David Christmas
- 3 Advanced Interventions Service, Area 7, Level 6, South Block, Ninewells Hospital and Medical School, Dundee, UK
| | - Keith Matthews
- 1 Division of Neuroscience, Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, U.K, DD1 9SY 3 Advanced Interventions Service, Area 7, Level 6, South Block, Ninewells Hospital and Medical School, Dundee, UK
| | - J Douglas Steele
- 1 Division of Neuroscience, Medical Research Institute, Ninewells Hospital and Medical School, University of Dundee, U.K, DD1 9SY 3 Advanced Interventions Service, Area 7, Level 6, South Block, Ninewells Hospital and Medical School, Dundee, UK
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