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Madanlal D, Guinard C, Nuñez VP, Becker S, Garnham J, Khayachi A, Léger S, O'Donovan C, Singh S, Stern S, Slaney C, Trappenberg T, Alda M, Nunes A. A pilot study examining the impact of lithium treatment and responsiveness on mnemonic discrimination in bipolar disorder. J Affect Disord 2024; 351:49-57. [PMID: 38280568 DOI: 10.1016/j.jad.2024.01.146] [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: 11/20/2023] [Revised: 01/09/2024] [Accepted: 01/14/2024] [Indexed: 01/29/2024]
Abstract
INTRODUCTION Mnemonic discrimination (MD), the ability to discriminate new stimuli from similar memories, putatively involves dentate gyrus pattern separation. Since lithium may normalize dentate gyrus functioning in lithium-responsive bipolar disorder (BD), we hypothesized that lithium treatment would be associated with better MD in lithium-responsive BD patients. METHODS BD patients (N = 69; NResponders = 16 [23 %]) performed the Continuous Visual Memory Test (CVMT), which requires discriminating between novel and previously seen images. Before testing, all patients had prophylactic lithium responsiveness assessed over ≥1 year of therapy (with the Alda Score), although only thirty-eight patients were actively prescribed lithium at time of testing (55 %; 12/16 responders, 26/53 nonresponders). We then used computational modelling to extract patient-specific MD indices. Linear models were used to test how (A) lithium treatment, (B) lithium responsiveness via the continuous Alda score, and (C) their interaction, affected MD. RESULTS Superior MD performance was associated with lithium treatment exclusively in lithium-responsive patients (Lithium x AldaScore β = 0.257 [SE 0.078], p = 0.002). Consistent with prior literature, increased age was associated with worse MD (β = -0.03 [SE 0.01], p = 0.005). LIMITATIONS Secondary pilot analysis of retrospectively collected data in a cross-sectional design limits generalizability. CONCLUSION Our study is the first to examine MD performance in BD. Lithium is associated with better MD performance only in lithium responders, potentially due to lithium's effects on dentate gyrus granule cell excitability. Our results may influence the development of behavioural probes for dentate gyrus neuronal hyperexcitability in BD.
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Affiliation(s)
- Dhanyaasri Madanlal
- Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Christian Guinard
- Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada; Faculty of Computer Science, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Vanessa Pardo Nuñez
- Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Suzanna Becker
- Department of Psychology, Neuroscience & Behaviour, McMaster University, Hamilton, Ontario, Canada
| | - Julie Garnham
- Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Anouar Khayachi
- Montreal Neurological Institute, Department of Neurology & Neurosurgery, McGill University, Montreal, Quebec, Canada
| | - Simon Léger
- Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Claire O'Donovan
- Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Selena Singh
- Department of Psychology, Neuroscience & Behaviour, McMaster University, Hamilton, Ontario, Canada
| | - Shani Stern
- Sagol Department of Neurobiology, Faculty of Natural Sciences, University of Haifa, Israel
| | - Claire Slaney
- Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Thomas Trappenberg
- Faculty of Computer Science, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Martin Alda
- Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Abraham Nunes
- Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada; Faculty of Computer Science, Dalhousie University, Halifax, Nova Scotia, Canada.
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Chang WL, Hen R. Adult Neurogenesis, Context Encoding, and Pattern Separation: A Pathway for Treating Overgeneralization. ADVANCES IN NEUROBIOLOGY 2024; 38:163-193. [PMID: 39008016 DOI: 10.1007/978-3-031-62983-9_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
In mammals, the subgranular zone of the dentate gyrus is one of two brain regions (with the subventricular zone of the olfactory bulb) that continues to generate new neurons throughout adulthood, a phenomenon known as adult hippocampal neurogenesis (AHN) (Eriksson et al., Nat Med 4:1313-1317, 1998; García-Verdugo et al., J Neurobiol 36:234-248, 1998). The integration of these new neurons into the dentate gyrus (DG) has implications for memory encoding, with unique firing and wiring properties of immature neurons that affect how the hippocampal network encodes and stores attributes of memory. In this chapter, we will describe the process of AHN and properties of adult-born cells as they integrate into the hippocampal circuit and mature. Then, we will discuss some methodological considerations before we review evidence for the role of AHN in two major processes supporting memory that are performed by the DG. First, we will discuss encoding of contextual information for episodic memories and how this is facilitated by AHN. Second, will discuss pattern separation, a major role of the DG that reduces interference for the formation of new memories. Finally, we will review clinical and translational considerations, suggesting that stimulation of AHN may help decrease overgeneralization-a common endophenotype of mood, anxiety, trauma-related, and age-related disorders.
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Affiliation(s)
- Wei-Li Chang
- Departments of Psychiatry and Neuroscience, Columbia University, New York, NY, USA
- Division of Systems Neuroscience, New York State Psychiatric Institute, New York, NY, USA
| | - Rene Hen
- Departments of Psychiatry and Neuroscience, Columbia University, New York, NY, USA.
- Division of Systems Neuroscience, New York State Psychiatric Institute, New York, NY, USA.
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Yun S, Soler I, Tran FH, Haas HA, Shi R, Bancroft GL, Suarez M, de Santis CR, Reynolds RP, Eisch AJ. Behavioral pattern separation and cognitive flexibility are enhanced in a mouse model of increased lateral entorhinal cortex-dentate gyrus circuit activity. Front Behav Neurosci 2023; 17:1151877. [PMID: 37324519 PMCID: PMC10267474 DOI: 10.3389/fnbeh.2023.1151877] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 04/26/2023] [Indexed: 06/17/2023] Open
Abstract
Behavioral pattern separation and cognitive flexibility are essential cognitive abilities that are disrupted in many brain disorders. A better understanding of the neural circuitry involved in these abilities will open paths to treatment. In humans and mice, discrimination and adaptation rely on the integrity of the hippocampal dentate gyrus (DG) which receives glutamatergic input from the entorhinal cortex (EC), including the lateral EC (LEC). An inducible increase of EC-DG circuit activity improves simple hippocampal-dependent associative learning and increases DG neurogenesis. Here, we asked if the activity of LEC fan cells that directly project to the DG (LEC → DG neurons) regulates the relatively more complex hippocampal-dependent abilities of behavioral pattern separation or cognitive flexibility. C57BL/6J male mice received bilateral LEC infusions of a virus expressing shRNA TRIP8b, an auxiliary protein of an HCN channel or a control virus (SCR shRNA). Prior work shows that 4 weeks post-surgery, TRIP8b mice have more DG neurogenesis and greater activity of LEC → DG neurons compared to SCR shRNA mice. Here, 4 weeks post-surgery, the mice underwent testing for behavioral pattern separation and reversal learning (touchscreen-based location discrimination reversal [LDR]) and innate fear of open spaces (elevated plus maze [EPM]) followed by quantification of new DG neurons (doublecortin-immunoreactive cells [DCX+] cells). There was no effect of treatment (SCR shRNA vs. TRIP8b) on performance during general touchscreen training, LDR training, or the 1st days of LDR testing. However, in the last days of LDR testing, the TRIP8b shRNA mice had improved pattern separation (reached the first reversal more quickly and had more accurate discrimination) compared to the SCR shRNA mice, specifically when the load on pattern separation was high (lit squares close together or "small separation"). The TRIP8b shRNA mice were also more cognitively flexible (achieved more reversals) compared to the SCR shRNA mice in the last days of LDR testing. Supporting a specific influence on cognitive behavior, the SCR shRNA and TRIP8b shRNA mice did not differ in total distance traveled or in time spent in the closed arms of the EPM. Supporting an inducible increase in LEC-DG activity, DG neurogenesis was increased. These data indicate that the TRIP8b shRNA mice had better pattern separation and reversal learning and more neurogenesis compared to the SCR shRNA mice. This study advances fundamental and translational neuroscience knowledge relevant to two cognitive functions critical for adaptation and survival-behavioral pattern separation and cognitive flexibility-and suggests that the activity of LEC → DG neurons merits exploration as a therapeutic target to normalize dysfunctional DG behavioral output.
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Affiliation(s)
- Sanghee Yun
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Ivan Soler
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
- University of Pennsylvania, Philadelphia, PA, United States
| | - Fionya H. Tran
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Harley A. Haas
- University of Pennsylvania, Philadelphia, PA, United States
| | - Raymon Shi
- University of Pennsylvania, Philadelphia, PA, United States
| | | | - Maiko Suarez
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Christopher R. de Santis
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Ryan P. Reynolds
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - Amelia J. Eisch
- Department of Anesthesiology and Critical Care Medicine, Children's Hospital of Philadelphia, Philadelphia, PA, United States
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
- Department of Neuroscience and Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
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Laing PAF, Dunsmoor JE. Pattern separation of fear extinction memory. Learn Mem 2023; 30:110-115. [PMID: 37433642 PMCID: PMC10353259 DOI: 10.1101/lm.053760.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 06/13/2023] [Indexed: 07/13/2023]
Abstract
While fear generalizes widely, extinction is stimulus-specific. Using a hybrid conditioning/episodic memory paradigm, subjects encoded nonrepeating category exemplars during fear conditioning and extinction. Twenty-four hours later, a surprise memory test included old, similar, and novel category exemplars. Results showed strong dissociation between pattern completion (generalization) and pattern separation (discrimination) in episodic memory for items encoded during fear conditioning versus extinction, respectively. These data suggest that directly threat-conditioned stimuli are better recognized at the expense of mnemonic precision, whereas discrimination is enhanced for extinguished stimuli. Overly precise extinction memory may be a contributing factor to fear relapse.
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Affiliation(s)
- Patrick A F Laing
- Department of Psychiatry and Behavioral Sciences, Dell Medical School, University of Texas at Austin, Austin, Texas 78712, USA
- Institute for Neuroscience, University of Texas at Austin, Austin, Texas 78712, USA
| | - Joseph E Dunsmoor
- Department of Psychiatry and Behavioral Sciences, Dell Medical School, University of Texas at Austin, Austin, Texas 78712, USA
- Institute for Neuroscience, University of Texas at Austin, Austin, Texas 78712, USA
- Department of Neuroscience, University of Texas at Austin, Austin, Texas 78712, USA
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5
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Neudert MK, Schäfer A, Zehtner RI, Fricke S, Seinsche RJ, Kruse O, Stark R, Hermann A. Behavioral pattern separation is associated with neural and electrodermal correlates of context-dependent fear conditioning. Sci Rep 2023; 13:5577. [PMID: 37019951 PMCID: PMC10076331 DOI: 10.1038/s41598-023-31504-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 03/13/2023] [Indexed: 04/07/2023] Open
Abstract
Hippocampus-dependent pattern separation is considered as a relevant factor for context discrimination and might therefore impact the contextual modulation of conditioned fear. However, the association between pattern separation and context-dependent fear conditioning has not been investigated so far. In the current study, 72 healthy female students completed the Mnemonic Similarity Task, a measure of behavioral pattern separation, in addition to a context-dependent fear conditioning paradigm during functional magnetic resonance imaging. The paradigm included fear acquisition in context A and extinction training in context B on a first day, as well as retrieval testing of the fear and extinction memories in the safe context B (extinction recall) and a novel context C (fear renewal) one day later. Main outcome measures comprised skin conductance responses (SCRs) and blood oxygen level-dependent responses in brain regions of the fear and extinction circuit. Regarding retrieval testing, pattern separation did not correlate with extinction recall, but with stronger dorsal anterior cingulate cortex activation and conditioned SCRs (trend) during fear renewal, indicating a stronger retrieval of the fear memory trace. Our findings suggest that behavioral pattern separation ability seems to be important for context-dependent fear modulation, which is impaired in patients with posttraumatic stress disorder.
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Affiliation(s)
- Marie K Neudert
- Department of Psychotherapy and Systems Neuroscience, Justus Liebig University Giessen, Giessen, Germany.
- Bender Institute of Neuroimaging, Justus Liebig University Giessen, Giessen, Germany.
| | - Axel Schäfer
- Bender Institute of Neuroimaging, Justus Liebig University Giessen, Giessen, Germany
- Center for Mind, Brain and Behavior, Phillips University Marburg and Justus Liebig University Giessen, Giessen, Germany
| | - Raphaela I Zehtner
- Department of Psychotherapy and Systems Neuroscience, Justus Liebig University Giessen, Giessen, Germany
- Bender Institute of Neuroimaging, Justus Liebig University Giessen, Giessen, Germany
| | - Susanne Fricke
- Department of Psychotherapy and Systems Neuroscience, Justus Liebig University Giessen, Giessen, Germany
- Bender Institute of Neuroimaging, Justus Liebig University Giessen, Giessen, Germany
| | - Rosa J Seinsche
- Department of Psychotherapy and Systems Neuroscience, Justus Liebig University Giessen, Giessen, Germany
- Bender Institute of Neuroimaging, Justus Liebig University Giessen, Giessen, Germany
| | - Onno Kruse
- Department of Psychotherapy and Systems Neuroscience, Justus Liebig University Giessen, Giessen, Germany
- Bender Institute of Neuroimaging, Justus Liebig University Giessen, Giessen, Germany
| | - Rudolf Stark
- Department of Psychotherapy and Systems Neuroscience, Justus Liebig University Giessen, Giessen, Germany
- Bender Institute of Neuroimaging, Justus Liebig University Giessen, Giessen, Germany
- Center for Mind, Brain and Behavior, Phillips University Marburg and Justus Liebig University Giessen, Giessen, Germany
| | - Andrea Hermann
- Department of Psychotherapy and Systems Neuroscience, Justus Liebig University Giessen, Giessen, Germany
- Bender Institute of Neuroimaging, Justus Liebig University Giessen, Giessen, Germany
- Center for Mind, Brain and Behavior, Phillips University Marburg and Justus Liebig University Giessen, Giessen, Germany
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6
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Nota MH, Nicolas S, O’Leary OF, Nolan YM. Outrunning a bad diet: interactions between exercise and a Western-style diet for adolescent mental health, metabolism and microbes. Neurosci Biobehav Rev 2023; 149:105147. [PMID: 36990371 DOI: 10.1016/j.neubiorev.2023.105147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/16/2023] [Accepted: 03/24/2023] [Indexed: 03/29/2023]
Abstract
Adolescence is a period of biological, psychological and social changes, and the peak time for the emergence of mental health problems. During this life stage, brain plasticity including hippocampal neurogenesis is increased, which is crucial for cognitive functions and regulation of emotional responses. The hippocampus is especially susceptible to environmental and lifestyle influences, mediated by changes in physiological systems, resulting in enhanced brain plasticity but also an elevated risk for developing mental health problems. Indeed, adolescence is accompanied by increased activation of the maturing hypothalamic-pituitary-adrenal axis, sensitivity to metabolic changes due to increased nutritional needs and hormonal changes, and gut microbiota maturation. Importantly, dietary habits and levels of physical activity significantly impact these systems. In this review, the interactions between exercise and Western-style diets, which are high in fat and sugar, on adolescent stress susceptibility, metabolism and the gut microbiota are explored. We provide an overview of current knowledge on implications of these interactions for hippocampal function and adolescent mental health, and speculate on potential mechanisms which require further investigation.
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7
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Grupe DW, Barnes AL, Gresham L, Kirvin-Quamme A, Nord E, Alexander AL, Abercrombie HC, Schaefer SM, Davidson RJ. Perceived stress associations with hippocampal-dependent behavior and hippocampal subfield volume. Neurobiol Stress 2022; 19:100469. [PMID: 35859546 PMCID: PMC9289864 DOI: 10.1016/j.ynstr.2022.100469] [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: 04/26/2022] [Revised: 06/13/2022] [Accepted: 07/05/2022] [Indexed: 12/04/2022] Open
Abstract
Background Individual differences in stress appraisals influence trajectories of risk and resilience following exposure to chronic and acute stressors. Smaller hippocampal volume may contribute to elevated stress appraisals via deficient pattern separation, a process depending on dentate gyrus (DG)/CA3 hippocampal subfields. Here, we investigated links between perceived stress, DG/CA3 volume, and behavioral pattern separation to test hypothesized mechanisms underlying stress-related psychopathology. Methods We collected the Perceived Stress Scale (PSS) and ratings of subjective stress reactivity during the Trier Social Stress Test (TSST) from 71 adult community participants. We obtained high-resolution T2 MRI scans and used Automatic Segmentation of Hippocampal Subfields to estimate DG/CA3 volume in 56 of these participants. Participants completed the mnemonic similarity task, which provides a behavioral index of pattern separation. Analyses investigated associations between perceived stress, DG/CA3 volume, and behavioral pattern separation, controlling for age, gender, hemisphere, and intracranial volume. Results Greater PSS scores and TSST subjective stress reactivity were each independently related to poorer behavioral pattern separation, together accounting for 15% of variance in behavioral performance in a simultaneous regression. Contrary to hypotheses, DG/CA3 volume was not associated with either stress measure, although exploratory analyses suggested a link between hippocampal volume asymmetry and PSS scores. Conclusions We observed novel associations between laboratory and questionnaire measures of perceived stress and a behavioral assay of pattern separation. Additional work is needed to clarify the involvement of the hippocampus in this stress-behavior relationship and determine the relevance of behavioral pattern separation for stress-related disorders.
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Affiliation(s)
- Daniel W Grupe
- University of Wisconsin-Madison Center for Healthy Minds, 625 W Washington Ave, Madison, WI, 53703, USA.,University of Wisconsin-Madison Waisman Laboratory for Brain Imaging and Behavior, 1500 Highland Ave, Madison, WI, 53705, USA
| | - Alexandra L Barnes
- University of Wisconsin-Madison Center for Healthy Minds, 625 W Washington Ave, Madison, WI, 53703, USA
| | - Lauren Gresham
- University of Wisconsin-Madison Center for Healthy Minds, 625 W Washington Ave, Madison, WI, 53703, USA
| | - Andrew Kirvin-Quamme
- University of Wisconsin-Madison Center for Healthy Minds, 625 W Washington Ave, Madison, WI, 53703, USA
| | - Elizabeth Nord
- University of Wisconsin-Madison Center for Healthy Minds, 625 W Washington Ave, Madison, WI, 53703, USA
| | - Andrew L Alexander
- University of Wisconsin-Madison Waisman Laboratory for Brain Imaging and Behavior, 1500 Highland Ave, Madison, WI, 53705, USA.,University of Wisconsin-Madison Department of Medical Physics, 1111 Highland Ave, Madison, WI, 53705, USA.,University of Wisconsin-Madison Department of Psychiatry, 6001 Research Park Blvd, Madison, WI, 53719, USA
| | - Heather C Abercrombie
- University of Wisconsin-Madison Center for Healthy Minds, 625 W Washington Ave, Madison, WI, 53703, USA.,University of Wisconsin-Madison Waisman Laboratory for Brain Imaging and Behavior, 1500 Highland Ave, Madison, WI, 53705, USA
| | - Stacey M Schaefer
- University of Wisconsin-Madison Center for Healthy Minds, 625 W Washington Ave, Madison, WI, 53703, USA.,University of Wisconsin-Madison Waisman Laboratory for Brain Imaging and Behavior, 1500 Highland Ave, Madison, WI, 53705, USA
| | - Richard J Davidson
- University of Wisconsin-Madison Center for Healthy Minds, 625 W Washington Ave, Madison, WI, 53703, USA.,University of Wisconsin-Madison Waisman Laboratory for Brain Imaging and Behavior, 1500 Highland Ave, Madison, WI, 53705, USA.,University of Wisconsin-Madison Department of Psychiatry, 6001 Research Park Blvd, Madison, WI, 53719, USA.,University of Wisconsin-Madison Department of Psychology, 1202 W Johnson St, Madison, WI, 53706, USA
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8
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Davidson P, Jönsson P, Johansson M. The association between mnemonic discrimination ability and differential fear learning. J Behav Ther Exp Psychiatry 2022; 75:101715. [PMID: 34959001 DOI: 10.1016/j.jbtep.2021.101715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 09/13/2021] [Accepted: 12/04/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND AND OBJECTIVES It is important to be able to learn which stimuli in our surroundings predict aversive outcomes. To maintain emotional well-being, it is similarly important to be able to learn which stimuli predict safety. The ability to discriminate between stimuli that predict danger and safety has been suggested to not only have an emotional component, but also a cognitive one. One such candidate mechanism is mnemonic discrimination (MD), the ability to differentiate between two memories that are similar but not identical. In the present study, we wanted to examine if MD performance helps to explain inter-individual differences in the ability to acquire a differentiated fear response during fear conditioning. METHODS Participants performed a task assessing MD ability, and then underwent a fear conditioning procedure. Fear responses were measured using skin conductance responses (SCRs). RESULTS Results revealed no support for MD ability being associated with to which degree a differentiated fear response was acquired, or with the time needed to acquire such a response. LIMITATIONS Our only outcome measurement was SCRs. Future studies need to include fear ratings, expectancy ratings and neural responses. Future studies also need to examine this using a stimulus material where the conditioned stimulus and the safety stimulus are more difficult to distinguish from each other. CONCLUSIONS If MD ability has a role in inhibiting overgeneralization of fear learning, this does not seem to be driven by MD already during the initial learning.
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Affiliation(s)
- Per Davidson
- Department of Psychology, Lund University, Box 213, 221 00, Lund, Sweden; Department of Psychiatry, Massachusetts General Hospital, CNY 149 13th Street, Charlestown, MA, 02129, USA; Department of Psychiatry, Harvard Medical School, CNY 149 13th Street, Charlestown, MA, 02129, USA.
| | - Peter Jönsson
- School of Education and Environment, Centre for Psychology, Kristianstad University, Elmetorpsvägen 15, 298 88, Kristianstad, Sweden
| | - Mikael Johansson
- Department of Psychology, Lund University, Box 213, 221 00, Lund, Sweden
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Anxiety and hippocampal neuronal activity: Relationship and potential mechanisms. COGNITIVE, AFFECTIVE & BEHAVIORAL NEUROSCIENCE 2022; 22:431-449. [PMID: 34873665 DOI: 10.3758/s13415-021-00973-y] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/11/2021] [Indexed: 12/15/2022]
Abstract
The hippocampus has been implicated in modulating anxiety. It interacts with a variety of brain regions, both cortical and subcortical areas regulating emotion and stress responses, including prefrontal cortex, amygdala, hypothalamus, and the nucleus accumbens, to adjust anxiety levels in response to a variety of stressful conditions. Growing evidence indicates that anxiety is associated with increased neuronal excitability in the hippocampus, and alterations in local regulation of hippocampal excitability have been suggested to underlie behavioral disruptions characteristic of certain anxiety disorders. Furthermore, studies have shown that some anxiolytics can treat anxiety by altering the excitability and plasticity of hippocampal neurons. Hence, identifying cellular and molecular mechanisms and neural circuits that regulate hippocampal excitability in anxiety may be beneficial for developing targeted interventions for treatment of anxiety disorders particularly for the treatment-resistant cases. We first briefly review a role of the hippocampus in fear. We then review the evidence indicating a relationship between the hippocampal activity and fear/anxiety and discuss some possible mechanisms underlying stress-induced hippocampal excitability and anxiety-related behavior.
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10
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Jennen L, Mazereel V, Lecei A, Samaey C, Vancampfort D, van Winkel R. Exercise to spot the differences: a framework for the effect of exercise on hippocampal pattern separation in humans. Rev Neurosci 2022; 33:555-582. [PMID: 35172422 DOI: 10.1515/revneuro-2021-0156] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 01/16/2022] [Indexed: 12/12/2022]
Abstract
Exercise has a beneficial effect on mental health and cognitive functioning, but the exact underlying mechanisms remain largely unknown. In this review, we focus on the effect of exercise on hippocampal pattern separation, which is a key component of episodic memory. Research has associated exercise with improvements in pattern separation. We propose an integrated framework mechanistically explaining this relationship. The framework is divided into three pathways, describing the pro-neuroplastic, anti-inflammatory and hormonal effects of exercise. The pathways are heavily intertwined and may result in functional and structural changes in the hippocampus. These changes can ultimately affect pattern separation through direct and indirect connections. The proposed framework might guide future research on the effect of exercise on pattern separation in the hippocampus.
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Affiliation(s)
- Lise Jennen
- KU Leuven, Department of Neurosciences, Center for Clinical Psychiatry, ON V Herestraat 49, bus 1029, 3000 Leuven, Belgium
| | - Victor Mazereel
- KU Leuven, Department of Neurosciences, Center for Clinical Psychiatry, ON V Herestraat 49, bus 1029, 3000 Leuven, Belgium.,University Psychiatric Center KU Leuven, Leuvensesteenweg 517, 3070 Leuven-Kortenberg, Belgium
| | - Aleksandra Lecei
- KU Leuven, Department of Neurosciences, Center for Clinical Psychiatry, ON V Herestraat 49, bus 1029, 3000 Leuven, Belgium
| | - Celine Samaey
- KU Leuven, Department of Neurosciences, Center for Clinical Psychiatry, ON V Herestraat 49, bus 1029, 3000 Leuven, Belgium
| | - Davy Vancampfort
- University Psychiatric Center KU Leuven, Leuvensesteenweg 517, 3070 Leuven-Kortenberg, Belgium.,KU Leuven Department of Rehabilitation Sciences, ON IV Herestraat 49, bus 1510, 3000, Leuven, Belgium
| | - Ruud van Winkel
- KU Leuven, Department of Neurosciences, Center for Clinical Psychiatry, ON V Herestraat 49, bus 1029, 3000 Leuven, Belgium.,University Psychiatric Center KU Leuven, Leuvensesteenweg 517, 3070 Leuven-Kortenberg, Belgium
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11
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Keeler J, Lambert E, Olivola M, Owen J, Xia J, Thuret S, Himmerich H, Cardi V, Treasure J. Lower pattern recognition memory scores in anorexia nervosa. J Eat Disord 2021; 9:49. [PMID: 33865451 PMCID: PMC8052530 DOI: 10.1186/s40337-021-00406-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 04/07/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND There is extensive evidence for volumetric reductions in the hippocampus in patients with anorexia nervosa (AN), however the impact on function is unclear. Pattern separation and recognition are hippocampus-dependent forms of learning thought to underlie stimulus discrimination. METHODS The present study used the Mnemonic Similarity Task to investigate pattern separation and recognition for the first time in patients with AN (N = 46) and healthy controls (N = 56). An Analysis of Covariance examined between-group differences, controlling for age, antidepressant use and method of task delivery (remote vs. in person). RESULTS When controlling for covariates, pattern recognition memory scores were lower in the AN group with a medium effect size (d = 0.51). In contrast, there was a small effect whereby patients with AN had a greater pattern separation score than controls (d = 0.34), albeit this difference was not significant at the p = 0.05 threshold (p = 0.133). Furthermore, pattern separation and recognition memory abilities were not related to age, body mass index, eating disorder psychopathology or trait anxiety levels. CONCLUSIONS This preliminary study provides initial evidence for an imbalance in pattern separation and recognition abilities in AN, a hippocampus-dependent cognitive ability. Further studies should endeavour to investigate pattern separation and recognition performance further in AN, as well as investigate other hippocampus-dependent functions.
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Affiliation(s)
- Johanna Keeler
- Section of Eating Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 103 Denmark Hill, London, SE5 8AF, UK.
| | - Ellen Lambert
- Section of Eating Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 103 Denmark Hill, London, SE5 8AF, UK
| | - Miriam Olivola
- Section of Eating Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 103 Denmark Hill, London, SE5 8AF, UK
- Department of Mental Health and Addictions, Azienda Socio-Sanitaria Territoriale di Pavia, Pavia, Italy
| | - Judith Owen
- Section of Eating Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 103 Denmark Hill, London, SE5 8AF, UK
| | - Jingjing Xia
- Section of Eating Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 103 Denmark Hill, London, SE5 8AF, UK
| | - Sandrine Thuret
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
- Department of Neurology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Hubertus Himmerich
- Section of Eating Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 103 Denmark Hill, London, SE5 8AF, UK
| | - Valentina Cardi
- Section of Eating Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 103 Denmark Hill, London, SE5 8AF, UK
- Department of General Psychology, University of Padova, Padova, Italy
| | - Janet Treasure
- Section of Eating Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 103 Denmark Hill, London, SE5 8AF, UK
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12
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Mnemonic discrimination is associated with individual differences in anxiety vulnerability. Behav Brain Res 2020; 401:113056. [PMID: 33290756 DOI: 10.1016/j.bbr.2020.113056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 11/24/2020] [Accepted: 12/02/2020] [Indexed: 02/06/2023]
Abstract
Increased generalization between fear-inducing stimuli (e.g., looking over the edge of a tall building) and perceptually-similar neutral stimuli (e.g., an aerial photograph) is observed in all subtypes of anxiety disorders, leading to avoidance behaviors that feed forward from the feared stimulus to other, seemingly unrelated stimuli. However, recent research suggests a much more nuanced relationship between generalization, discrimination, and behavior. This study seeks to extend current understanding by using a mnemonic discrimination task to explore the relationship between risk for anxiety and differences in mnemonic discrimination abilities. Participants self-reported trait anxiety and behavioral inhibition (a temperamental construct linked to risk for anxiety), and also completed a memory task. After incidental encoding of color photographs of neutral everyday objects, participants performed a surprise recognition task, where they categorized each test image as "old" (identical to a previously viewed image), "similar" (new but perceptually-similar to a studied image, with half the images being highly similar and the other half being less similar to the studied images), or "new" (new and perceptually-dissimilar to studied images). We found that those with high behavioral inhibition are more successful at discriminating between previously seen "old" items from highly similar items. In contrast, those with high trait anxiousness are less successful at the same kind of discrimination. Interestingly, these relationships were not apparent in low similarity items. Our data suggest that behavioral inhibition and trait anxiety may be associated with unique aspects of individual differences in mnemonic discrimination abilities.
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13
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Bernstein EE, van der Does F, Orr SP, McNally RJ. Poor Mnemonic Discrimination Predicts Overgeneralization of Fear. JOURNAL OF PSYCHOPATHOLOGY AND BEHAVIORAL ASSESSMENT 2020. [DOI: 10.1007/s10862-020-09846-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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14
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Davidson P, Jönsson P, Johansson M. A daytime nap does not increase mnemonic discrimination ability. J Sleep Res 2020; 30:e13128. [PMID: 32557911 DOI: 10.1111/jsr.13128] [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: 10/01/2019] [Revised: 03/26/2020] [Accepted: 05/25/2020] [Indexed: 11/30/2022]
Abstract
It has been proposed that sleep readies the brain for novel learning, and previous work has shown that sleep loss impairs the ability to encode new memories. In the present study, we examined if a daytime nap would increase mnemonic discrimination (MD) performance. MD is the ability to differentiate between memories that are similar but not identical. Participants performed the Mnemonic Similarity Task (MST) twice, once in the morning and once in the afternoon. The goal of this task is to distinguish stimuli that have been seen before from novel stimuli that are similar but not identical. After the morning MST, participants were randomly allocated into either a sleep or a wake group. The sleep group had a 2-hr nap opportunity, whereas the wake group spent a similar amount of time passively resting. All participants then performed a second MST in the afternoon with a novel set of images. Results did not show any support for increased MD ability after a nap. There was, however, a correlation showing that an increase in sleepiness between sessions predicted a decrease in MD performance. Future work must systematically examine how strong sleep manipulations that are needed for sleep to have an effect on encoding ability, as well as which kind of memory tasks that are sensitive to sleep manipulations. More knowledge about the relationship between sleep and the ability to differentiate similar memories from each other is important because impaired MD ability has previously been reported in various groups in which sleep disturbances are also common.
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Affiliation(s)
- Per Davidson
- Department of Psychology, Lund University, Lund, Sweden.,Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA.,Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Peter Jönsson
- School of Education of Environment, Centre for Psychology, Kristianstad University, Kristianstad, Sweden
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15
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Abstract
The Mnemonic Similarity Task (MST) measures mnemonic discrimination, or the ability to correctly identify new stimuli from highly similar, old stimuli. Poor mnemonic discrimination is a potential risk or maintenance factor for anxiety, and recent studies suggest state affect may moderate relations between mnemonic discrimination and trait anxiety. No studies have evaluated mnemonic discrimination in specific subtypes of anxiety or with clinically relevant stressors. This preregistered study evaluated the role of social anxiety and the anticipation of a future speech on MST performance. Participants with high (n = 66) and low (n = 64) levels of social anxiety were randomly assigned to a stressor condition or a control condition prior to the MST. State anxiety was measured throughout the study. Results did not indicate significant effects of trait (high vs. low social anxiety) or state anxiety (stressor condition vs. control condition) on mnemonic discrimination. Results are compared with previous research and implications and future directions are discussed.
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Affiliation(s)
| | - Shari A Steinman
- Department of Psychology, West Virginia University, Morgantown, USA
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16
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Mnemonic discrimination in treatment-seeking adults with and without PTSD. Behav Res Ther 2020; 131:103650. [PMID: 32504887 DOI: 10.1016/j.brat.2020.103650] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 03/24/2020] [Accepted: 05/21/2020] [Indexed: 11/22/2022]
Abstract
Posttraumatic stress disorder (PTSD) is characterized by overgeneralized emotional reactivity following a trauma. Similarities between current, safe contexts and past, threatening events trigger recurrent, distressing responses and can contribute to a host of symptoms, including reexperiencing and hypervigilance. Mnemonic discrimination, a component process of episodic memory, could promote overgeneralization when impaired. Mnemonic discrimination reflects the integration of old and new experiences and one's ability to differentiate them despite their similarities. To date, little research has been conducted in clinical populations and none with individuals with PTSD. In this study, we examined mnemonic discrimination performance among treatment-seeking adults with and without PTSD and healthy comparison participants (n = 190). There were significant group differences in mnemonic discrimination performance, but not in general recognition memory. Individuals without psychopathology outperformed individuals with PTSD and treatment-seeking individuals without PTSD. However, there were no differences in mnemonic discrimination performance among individuals with PTSD and any other diagnoses. Finally, clinical groups with or without trauma exposure also did not differ in mnemonic discrimination performance. Results held when we adjusted for general recognition memory. Findings suggest that poor mnemonic discrimination is transdiagnostically associated with emotional disorders. Future work is merited to explore this as a measurable and potentially malleable, though non-specific, risk factor.
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Stark SM, Kirwan CB, Stark CEL. Mnemonic Similarity Task: A Tool for Assessing Hippocampal Integrity. Trends Cogn Sci 2019; 23:938-951. [PMID: 31597601 DOI: 10.1016/j.tics.2019.08.003] [Citation(s) in RCA: 135] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 08/19/2019] [Accepted: 08/20/2019] [Indexed: 12/25/2022]
Abstract
The hippocampus is critical for learning and memory, relying in part on pattern separation processes supported by the dentate gyrus (DG) to prevent interference from overlapping memory representations. In 2007, we designed the Mnemonic Similarity Task (MST), a modified object recognition memory task, to be highly sensitive to hippocampal function by placing strong demands on pattern separation. The MST is now a widely used behavioral task, repeatedly shown to be sensitive to age-related memory decline, hippocampal connectivity, and hippocampal function, with specificity to the DG. Here, we review the utility of the MST, its relationship to hippocampal function, its utility in detecting hippocampal-based memory alterations across the lifespan, and impairments associated with clinical pathology from a variety of disorders.
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Affiliation(s)
- Shauna M Stark
- Department of Neurobiology and Behavior, University of California, Irvine, CA, USA
| | - C Brock Kirwan
- Department of Psychology, Neuroscience Center, Brigham Young University, Provo, UT, USA
| | - Craig E L Stark
- Department of Neurobiology and Behavior, University of California, Irvine, CA, USA.
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18
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Quagliato LA, Freire RC, Nardi AE. Elevated peripheral kynurenine/tryptophan ratio predicts poor short-term auditory memory in panic disorder patients. J Psychiatr Res 2019; 113:159-164. [PMID: 30959226 DOI: 10.1016/j.jpsychires.2019.03.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 03/24/2019] [Accepted: 03/28/2019] [Indexed: 01/04/2023]
Abstract
Abnormalities in the kynurenine pathway (KP) have been implicated in the cognitive deficits of psychiatry disorders, possibly through cytokines that increase the activity of indoleamine-2,3 dioxygenase (IDO), a key enzyme for tryptophan-to-kynurenine conversion. Some studies on panic disorder (PD) have detected elevated cytokines in blood. We aimed to determine the extent to which elevated peripheral cytokine levels and kynurenine/tryptophan (kyn/tryp) ratio (1) are biological markers for PD patients and (2) are related to cognition in PD. Seventy-eight PD patients and matched healthy controls were assessed for peripheral serum levels of interleukin (IL)-2R, IL-1β, IL-10, kynurenine and tryptophan. The subjects were evaluated for episodic and short-term memory, selective attention and cognitive flexibility. In patients, IL-2R levels, which are involved in the regulation of IDO, were significantly associated with levels of kynurenine (p = .029), but this association was not observed in controls. Importantly, an elevated kyn/tryp ratio significantly predicted poor digit span forward (p = .004) and total (p = .004) scores in individuals with PD. This study is the first to link blood biomarkers of infiammation and the KP with cognitive deficits in PD subjects, suggesting that those with an elevated kyn/tryp ratio might have short-term auditory memory impairment. These findings indicate that treatments targeting the KP may ameliorate cognitive abnormalities in PD patients.
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Affiliation(s)
- Laiana A Quagliato
- Laboratory of Panic & Respiration, Institute of Psychiatry, Federal University of Rio de Janeiro, Rua Ataulfo de Paiva 135 S. 609, 22440-901, Brazil.
| | - Rafael C Freire
- Laboratory of Panic & Respiration, Institute of Psychiatry, Federal University of Rio de Janeiro, Rua Ataulfo de Paiva 135 S. 609, 22440-901, Brazil
| | - Antonio E Nardi
- Laboratory of Panic & Respiration, Institute of Psychiatry, Federal University of Rio de Janeiro, Rua Ataulfo de Paiva 135 S. 609, 22440-901, Brazil
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19
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Bernstein EE, Heeren A, McNally RJ. Reexamining trait rumination as a system of repetitive negative thoughts: A network analysis. J Behav Ther Exp Psychiatry 2019; 63:21-27. [PMID: 30590225 DOI: 10.1016/j.jbtep.2018.12.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 12/14/2018] [Accepted: 12/18/2018] [Indexed: 01/13/2023]
Abstract
BACKGROUND AND OBJECTIVES Rumination is strongly associated with risk, maintenance, and worsening of depressive and related symptoms, and it predicts poor treatment response and relapse. More work is needed to clarify the nature and malleability of rumination. We propose reexamining trait rumination as a system of interacting components ("nodes"). METHODS A regularized partial correlation network was first computed to estimate the functional relations among items from the Ruminative Responses Scale (RRS) (N = 403). We then tested whether items constitute multiple distinguishable sub-networks or communities, and if so, if particular items function as "bridges" connecting them. RESULTS RRS items were not interchangeable, with network components varying widely in their centrality. We identified three communities of nodes and the nodes bridging these communities. LIMITATIONS Data were derived from a heterogeneous community sample and include items from a single measure. Thus, results should not be interpreted as definitive, but instead as hypothesis-generating and highlighting the utility of rethinking the conceptualization and measurement of rumination. CONCLUSIONS Of the larger set of cognitive patterns forming the rumination construct, the high centrality nodes were largely passive and self-critical processes. Community detection analyses identified a sub-network largely comprising items from the RRS that have traditionally been labeled reflective pondering and adaptive; however, strong bridge nodes were also from this community. This implies that in isolation or at low levels such processes may not be problematic, but that their persistence or intensification could be associated with the activation of more maladaptive processes.
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Affiliation(s)
- Emily E Bernstein
- Department of Psychology, Harvard University, 33 Kirkland Street, Cambridge, MA, 02138, USA.
| | - Alexandre Heeren
- Psychological Sciences Research Institute & Institute of Neuroscience, Université Catholique de Louvain, Place du Cardinal Mercier, 10, 1348, Louvain-la-Neuve, Belgium.
| | - Richard J McNally
- Department of Psychology, Harvard University, 33 Kirkland Street, Cambridge, MA, 02138, USA.
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20
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Voss MW, Soto C, Yoo S, Sodoma M, Vivar C, van Praag H. Exercise and Hippocampal Memory Systems. Trends Cogn Sci 2019; 23:318-333. [PMID: 30777641 PMCID: PMC6422697 DOI: 10.1016/j.tics.2019.01.006] [Citation(s) in RCA: 122] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 01/11/2019] [Accepted: 01/16/2019] [Indexed: 01/17/2023]
Abstract
No medications prevent or reverse age-related cognitive decline. Physical activity (PA) enhances memory in rodents, but findings are mixed in human studies. As a result, exercise guidelines specific for brain health are absent. Here, we re-examine results from human studies, and suggest the use of more sensitive tasks to evaluate PA effects on age-related changes in the hippocampus, such as relational memory and mnemonic discrimination. We discuss recent advances from rodent and human studies into the underlying mechanisms at both the central and peripheral levels, including neurotrophins and myokines that could contribute to improved memory. Finally, we suggest guidelines for future research to help expedite well-founded PA recommendations for the public.
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Affiliation(s)
- Michelle W Voss
- Department of Psychological and Brain Sciences, University of Iowa, Iowa City, IA, USA.
| | - Carmen Soto
- Laboratory of Neurogenesis and Neuroplasticity, Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies of the National Polytechnic Institute, Mexico City, Mexico
| | - Seungwoo Yoo
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, and Brain Institute, Florida Atlantic University, Jupiter, FL 33458, USA
| | - Matthew Sodoma
- Department of Psychological and Brain Sciences, University of Iowa, Iowa City, IA, USA
| | - Carmen Vivar
- Laboratory of Neurogenesis and Neuroplasticity, Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies of the National Polytechnic Institute, Mexico City, Mexico
| | - Henriette van Praag
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, and Brain Institute, Florida Atlantic University, Jupiter, FL 33458, USA
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