1
|
Chen EYH, Wong SMY, Tang EYH, Lei LKS, Suen YN, Hui CLM. Spurious Autobiographical Memory of Psychosis: A Mechanistic Hypothesis for the Resolution, Persistence, and Recurrence of Positive Symptoms in Psychotic Disorders. Brain Sci 2023; 13:1069. [PMID: 37509001 PMCID: PMC10376952 DOI: 10.3390/brainsci13071069] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 07/06/2023] [Accepted: 07/12/2023] [Indexed: 07/30/2023] Open
Abstract
Psychotic disorders are complex disorders with multiple etiologies. While increased dopamine synthesis capacity has been proposed to underlie psychotic episodes, dopamine-independent processes are also involved (less responsive to dopamine receptor-blocking medications). The underlying mechanism(s) of the reduction in antipsychotic responsiveness over time, especially after repeated relapses, remain unclear. Despite the consistent evidence of dopamine overactivity and hippocampal volume loss in schizophrenia, few accounts have been provided based on the interactive effect of dopamine on hippocampal synapse plasticity mediating autobiographical memory processes. The present hypothesis builds upon previous works showing the potential effects of dopamine overactivity on hippocampal-mediated neuroplasticity underlying autobiographical memory, alongside known patterns of autobiographical memory dysfunction in psychosis. We propose that spurious autobiographical memory of psychosis (SAMP) produced during active psychosis may be a key mechanism mediating relapses and treatment non-responsiveness. In a hyperdopaminergic state, SAMP is expected to be generated at an increased rate during active psychosis. Similar to other memories, it will undergo assimilation, accommodation, and extinction processes. However, if SAMP fails to integrate with existing memory, a discontinuity in autobiographical memory may result. Inadequate exposure to normalizing experiences and hyposalience due to overmedication or negative symptoms may also impede the resolution of SAMP. Residual SAMP is hypothesized to increase the propensity for relapse and treatment non-responsiveness. Based on recent findings on the role of dopamine in facilitating hippocampal synapse plasticity and autobiographical memory formation, the SAMP hypothesis is consistent with clinical observations of DUP effects, including the repetition of contents in psychotic relapses as well as the emergence of treatment non-responsiveness after repeated relapses. Clinical implications of the hypothesis highlight the importance of minimizing active psychosis, integrating psychosis memory, avoiding over-medication, and fostering normalizing experiences.
Collapse
Affiliation(s)
- Eric Y H Chen
- Department of Psychiatry, School of Clinical Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
- The State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, China
| | - Stephanie M Y Wong
- Department of Psychiatry, School of Clinical Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Eric Y H Tang
- Department of Psychiatry, School of Clinical Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Lauren K S Lei
- Department of Psychiatry, School of Clinical Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Yi-Nam Suen
- Department of Psychiatry, School of Clinical Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Christy L M Hui
- Department of Psychiatry, School of Clinical Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| |
Collapse
|
2
|
Glutamatergic dysfunction leads to a hyper-dopaminergic phenotype through deficits in short-term habituation: a mechanism for aberrant salience. Mol Psychiatry 2023; 28:579-587. [PMID: 36460723 PMCID: PMC9908551 DOI: 10.1038/s41380-022-01861-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 10/19/2022] [Accepted: 10/28/2022] [Indexed: 12/05/2022]
Abstract
Psychosis in disorders like schizophrenia is commonly associated with aberrant salience and elevated striatal dopamine. However, the underlying cause(s) of this hyper-dopaminergic state remain elusive. Various lines of evidence point to glutamatergic dysfunction and impairments in synaptic plasticity in the etiology of schizophrenia, including deficits associated with the GluA1 AMPAR subunit. GluA1 knockout (Gria1-/-) mice provide a model of impaired synaptic plasticity in schizophrenia and exhibit a selective deficit in a form of short-term memory which underlies short-term habituation. As such, these mice are unable to reduce attention to recently presented stimuli. In this study we used fast-scan cyclic voltammetry to measure phasic dopamine responses in the nucleus accumbens of Gria1-/- mice to determine whether this behavioral phenotype might be a key driver of a hyper-dopaminergic state. There was no effect of GluA1 deletion on electrically-evoked dopamine responses in anaesthetized mice, demonstrating normal endogenous release properties of dopamine neurons in Gria1-/- mice. Furthermore, dopamine signals were initially similar in Gria1-/- mice compared to controls in response to both sucrose rewards and neutral light stimuli. They were also equally sensitive to changes in the magnitude of delivered rewards. In contrast, however, these stimulus-evoked dopamine signals failed to habituate with repeated presentations in Gria1-/- mice, resulting in a task-relevant, hyper-dopaminergic phenotype. Thus, here we show that GluA1 dysfunction, resulting in impaired short-term habituation, is a key driver of enhanced striatal dopamine responses, which may be an important contributor to aberrant salience and psychosis in psychiatric disorders like schizophrenia.
Collapse
|
3
|
Panula JM, Alho J, Lindgren M, Kieseppä T, Suvisaari J, Raij TT. State-like changes in the salience network correlate with delusion severity in first-episode psychosis patients. Neuroimage Clin 2022; 36:103234. [PMID: 36270161 PMCID: PMC9668644 DOI: 10.1016/j.nicl.2022.103234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 09/17/2022] [Accepted: 10/14/2022] [Indexed: 11/11/2022]
Abstract
BACKGROUND AND HYPOTHESIS Delusions are characteristic of psychotic disorders; however, the brain correlates of delusions remain poorly known. Imaging studies on delusions typically compare images across individuals. Related confounding of inter-individual differences beyond delusions may be avoided by comparing delusional and non-delusional states within individuals. STUDY DESIGN We studied correlations of delusions using intra-subject correlation (intra-SC) and inter-subject correlation of functional magnetic resonance imaging (fMRI) signal time series, obtained during a movie stimulus at baseline and follow-up. We included 27 control subjects and 24 first-episode psychosis patients, who were free of delusions at follow-up, to calculate intra-SC between fMRI signals obtained during the two time points. In addition, we studied changes in functional connectivity at baseline and during the one-year follow-up using regions where delusion severity correlated with intra-SC as seeds. RESULTS The intra-SC correlated negatively with the baseline delusion severity in the bilateral anterior insula. In addition, we observed a subthreshold cluster in the anterior cingulate. These three regions constitute the cortical salience network (SN). Functional connectivity between the bilateral insula and the precuneus was weaker in the patients at baseline than in patients at follow-up or in control subjects at any time point. CONCLUSIONS The results suggest that intra-SC is a powerful tool to study brain correlates of symptoms and highlight the role of the SN and internetwork dysconnectivity between the SN and the default mode network in delusions.
Collapse
Affiliation(s)
- Jonatan M Panula
- Department of Psychiatry, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Department of Neuroscience and Biomedical Engineering and Advanced Magnetic Imaging Center, Aalto University School of Science, Espoo, Finland.
| | - Jussi Alho
- Department of Neuroscience and Biomedical Engineering and Advanced Magnetic Imaging Center, Aalto University School of Science, Espoo, Finland
| | - Maija Lindgren
- Mental Health, Public Health and Welfare, Finnish Institute for Health and Welfare, Helsinki, Finland
| | - Tuula Kieseppä
- Department of Psychiatry, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Institute for Molecular Medicine Finland (FIMM), University of Helsinki, Helsinki, Finland
| | - Jaana Suvisaari
- Mental Health, Public Health and Welfare, Finnish Institute for Health and Welfare, Helsinki, Finland
| | - Tuukka T Raij
- Department of Psychiatry, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Department of Neuroscience and Biomedical Engineering and Advanced Magnetic Imaging Center, Aalto University School of Science, Espoo, Finland
| |
Collapse
|
4
|
Assmann A, Richter A, Schütze H, Soch J, Barman A, Behnisch G, Knopf L, Raschick M, Schult A, Wüstenberg T, Behr J, Düzel E, Seidenbecher CI, Schott BH. Neurocan genome-wide psychiatric risk variant affects explicit memory performance and hippocampal function in healthy humans. Eur J Neurosci 2020; 53:3942-3959. [PMID: 32583466 DOI: 10.1111/ejn.14872] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 06/04/2020] [Accepted: 06/15/2020] [Indexed: 12/26/2022]
Abstract
Alterations of the brain extracellular matrix (ECM) can perturb the structure and function of brain networks like the hippocampus, a key region in human memory that is commonly affected in psychiatric disorders. Here, we investigated the potential effects of a genome-wide psychiatric risk variant in the NCAN gene encoding the ECM proteoglycan neurocan (rs1064395) on memory performance, hippocampal function and cortical morphology in young, healthy volunteers. We assessed verbal memory performance in two cohorts (N = 572, 302) and found reduced recall performance in risk allele (A) carriers across both cohorts. In 117 participants, we performed functional magnetic resonance imaging using a novelty-encoding task with visual scenes. Risk allele carriers showed higher false alarm rates during recognition, accompanied by inefficiently increased left hippocampal activation. To assess effects of rs1064395 on brain morphology, we performed voxel-based morphometry in 420 participants from four independent cohorts and found lower grey matter density in the ventrolateral and rostral prefrontal cortex of risk allele carriers. In silico eQTL analysis revealed that rs1064395 SNP is linked not only to increased prefrontal expression of the NCAN gene itself, but also of the neighbouring HAPLN4 gene, suggesting a more complex effect of the SNP on ECM composition. Our results suggest that the NCAN rs1064395 A allele is associated with lower hippocampus-dependent memory function, variation of prefrontal cortex structure and ECM composition. Considering the well-documented hippocampal and prefrontal dysfunction in bipolar disorder and schizophrenia, our results may reflect an intermediate phenotype by which NCAN rs1064395 contributes to disease risk.
Collapse
Affiliation(s)
- Anne Assmann
- Leibniz Institute for Neurobiology, Magdeburg, Germany.,Department of Neurology, Otto von Guericke University, Magdeburg, Germany.,German Center for Neurodegenerative Diseases, Magdeburg, Germany
| | - Anni Richter
- Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Hartmut Schütze
- German Center for Neurodegenerative Diseases, Magdeburg, Germany.,Institute of Cognitive Neurology and Dementia Research, Otto von Guericke University, Magdeburg, Germany
| | - Joram Soch
- German Center for Neurodegenerative Diseases, Göttingen, Germany.,Bernstein Center for Computational Neuroscience, Humboldt University, Berlin, Germany
| | | | | | - Lea Knopf
- Leibniz Institute for Neurobiology, Magdeburg, Germany.,Department of Neurology, Otto von Guericke University, Magdeburg, Germany
| | - Matthias Raschick
- Leibniz Institute for Neurobiology, Magdeburg, Germany.,Department of Neurology, Otto von Guericke University, Magdeburg, Germany
| | - Annika Schult
- Leibniz Institute for Neurobiology, Magdeburg, Germany.,Department of Neurology, Otto von Guericke University, Magdeburg, Germany
| | - Torsten Wüstenberg
- Department of Psychiatry and Psychotherapy, Charité University Medicine, Berlin, Germany.,Department of Clinical Psychology and Psychotherapy, Institute of Psychology, University of Heidelberg, Heidelberg, Germany
| | - Joachim Behr
- Department of Psychiatry and Psychotherapy, Charité University Medicine, Berlin, Germany.,Department of Psychiatry and Psychotherapy, Medical School Brandenburg, Neuruppin, Germany
| | - Emrah Düzel
- German Center for Neurodegenerative Diseases, Magdeburg, Germany.,Institute of Cognitive Neurology and Dementia Research, Otto von Guericke University, Magdeburg, Germany.,Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
| | - Constanze I Seidenbecher
- Leibniz Institute for Neurobiology, Magdeburg, Germany.,Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
| | - Björn H Schott
- Leibniz Institute for Neurobiology, Magdeburg, Germany.,German Center for Neurodegenerative Diseases, Göttingen, Germany.,Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany.,Department of Psychiatry and Psychotherapy, University Medicine Göttingen, Germany
| |
Collapse
|
5
|
Harris MA, Shen X, Cox SR, Gibson J, Adams MJ, Clarke TK, Deary IJ, Lawrie SM, McIntosh AM, Whalley HC. Stratifying major depressive disorder by polygenic risk for schizophrenia in relation to structural brain measures. Psychol Med 2020; 50:1653-1662. [PMID: 31317844 DOI: 10.1017/s003329171900165x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Substantial clinical heterogeneity of major depressive disorder (MDD) suggests it may group together individuals with diverse aetiologies. Identifying distinct subtypes should lead to more effective diagnosis and treatment, while providing more useful targets for further research. Genetic and clinical overlap between MDD and schizophrenia (SCZ) suggests an MDD subtype may share underlying mechanisms with SCZ. METHODS The present study investigated whether a neurobiologically distinct subtype of MDD could be identified by SCZ polygenic risk score (PRS). We explored interactive effects between SCZ PRS and MDD case/control status on a range of cortical, subcortical and white matter metrics among 2370 male and 2574 female UK Biobank participants. RESULTS There was a significant SCZ PRS by MDD interaction for rostral anterior cingulate cortex (RACC) thickness (β = 0.191, q = 0.043). This was driven by a positive association between SCZ PRS and RACC thickness among MDD cases (β = 0.098, p = 0.026), compared to a negative association among controls (β = -0.087, p = 0.002). MDD cases with low SCZ PRS showed thinner RACC, although the opposite difference for high-SCZ-PRS cases was not significant. There were nominal interactions for other brain metrics, but none remained significant after correcting for multiple comparisons. CONCLUSIONS Our significant results indicate that MDD case-control differences in RACC thickness vary as a function of SCZ PRS. Although this was not the case for most other brain measures assessed, our specific findings still provide some further evidence that MDD in the presence of high genetic risk for SCZ is subtly neurobiologically distinct from MDD in general.
Collapse
Affiliation(s)
- Mathew A Harris
- Division of Psychiatry, University of Edinburgh, Edinburgh, UK
| | - Xueyi Shen
- Division of Psychiatry, University of Edinburgh, Edinburgh, UK
| | - Simon R Cox
- Department of Psychology, University of Edinburgh, Edinburgh, UK
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK
| | - Jude Gibson
- Division of Psychiatry, University of Edinburgh, Edinburgh, UK
| | - Mark J Adams
- Division of Psychiatry, University of Edinburgh, Edinburgh, UK
| | - Toni-Kim Clarke
- Division of Psychiatry, University of Edinburgh, Edinburgh, UK
| | - Ian J Deary
- Department of Psychology, University of Edinburgh, Edinburgh, UK
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK
| | | | - Andrew M McIntosh
- Division of Psychiatry, University of Edinburgh, Edinburgh, UK
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK
| | | |
Collapse
|
6
|
Bartsch JC, Behr J. Noncanonical, Dopamine-Dependent Long-Term Potentiation at Hippocampal Output Synapses in a Rodent Model of First-Episode Psychosis. Front Mol Neurosci 2020; 13:55. [PMID: 32317931 PMCID: PMC7146052 DOI: 10.3389/fnmol.2020.00055] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 03/17/2020] [Indexed: 12/16/2022] Open
Abstract
Cognitive deficits and positive symptoms in schizophrenia have both been linked to hippocampal dysfunction. Recently, subregion-specific aberrant and maladaptive hippocampal synaptic plasticity has been suggested as one of the mechanistic underpinnings. The subiculum is the final output hub of the hippocampus and orchestrates hippocampal information transfer to other brain regions. While most CA1 pyramidal neurons show regular-spiking behavior, subicular output neurons comprise bursting and regular-firing pyramidal cells. These two cell types target different brain regions and express unique forms of synaptic plasticity. Here, we used a single systemic application of the noncompetitive glutamatergic N-methyl-D-aspartate receptor (NMDAR) antagonist MK-801 to model first-episode psychosis in rats and studied long-term potentiation (LTP) in subicular regular-firing cells in acute hippocampal slices. Previously, we have reported a facilitation of a presynaptic, late-onset LTP in subicular bursting pyramidal cells after systemic NMDAR antagonism. Here, we show that single systemic NMDAR antagonist application also facilitates the induction of a noncanonical, but postsynaptic NMDAR-independent LTP in ventral subicular but not in CA1 regular-firing pyramidal cells. This form of LTP was dependent on D1/D5 dopamine receptor activation. Activation of D1/D5 dopamine receptors by a specific agonist mimicked and occluded LTP induced by electrical high-frequency stimulation (HFS). Furthermore, our results indicate that this form of LTP relies on postsynaptic Ca2+ signaling and requires the activation of protein kinase A. Considering the pivotal role of the subiculum as information gatekeeper between the hippocampus and other brain regions, this aberrant LTP in ventral subicular regular-firing neurons is expected to interfere with physiological hippocampal output processing and might thereby contribute to hippocampal dysfunction in psychotic events.
Collapse
Affiliation(s)
- Julia C Bartsch
- Department of Psychiatry and Psychotherapy, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Joachim Behr
- Department of Psychiatry and Psychotherapy, Charité-Universitätsmedizin Berlin, Berlin, Germany.,Department of Psychiatry, Psychotherapy and Psychosomatic Medicine, Brandenburg Medical School, Neuruppin, Germany
| |
Collapse
|
7
|
Lander SS, Chornyy S, Safory H, Gross A, Wolosker H, Gaisler‐Salomon I. Glutamate dehydrogenase deficiency disrupts glutamate homeostasis in hippocampus and prefrontal cortex and impairs recognition memory. GENES BRAIN AND BEHAVIOR 2020; 19:e12636. [DOI: 10.1111/gbb.12636] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 12/11/2019] [Accepted: 12/30/2019] [Indexed: 12/13/2022]
Affiliation(s)
| | - Sergiy Chornyy
- Department of PsychologyUniversity of Haifa Haifa Israel
| | - Hazem Safory
- Department of Biochemistry, The Ruth and Bruce Rappaport Faculty of MedicineTechnion‐Israel Institute of Technology Haifa Israel
| | - Amit Gross
- Department of PsychologyUniversity of Haifa Haifa Israel
| | - Herman Wolosker
- Department of Biochemistry, The Ruth and Bruce Rappaport Faculty of MedicineTechnion‐Israel Institute of Technology Haifa Israel
| | | |
Collapse
|
8
|
Ma X, Zheng W, Li C, Li Z, Tang J, Yuan L, Ouyang L, Jin K, He Y, Chen X. Decreased regional homogeneity and increased functional connectivity of default network correlated with neurocognitive deficits in subjects with genetic high-risk for schizophrenia: A resting-state fMRI study. Psychiatry Res 2019; 281:112603. [PMID: 31622873 DOI: 10.1016/j.psychres.2019.112603] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 10/04/2019] [Accepted: 10/04/2019] [Indexed: 01/01/2023]
Abstract
The complex symptoms of schizophrenia (SCZ) have been associated with dysfunction of the default mode network (DMN). Subjects at genetic high risk (GHR) for SCZ exhibit similar but milder brain abnormalities. This study aimed to investigate functional alterations of DMN from the local to the whole and their relationships with cognitive deficits in GHR subjects. 42 GHR subjects and 38 matched healthy controls (HC) were studied by resting-state functional magnetic resonance imaging (rs-fMRI). Regional homogeneity (ReHo) analysis was performed to measure the local brain function of the DMN, derived by the group independent component analysis, and areas with aberrant ReHo were used as seeds in functional connectivity (FC). Compared with the HC group, the GHR group exhibited significantly decreased ReHo and increased FC in the fronto-limbic-striatal system within the DMN. Furthermore, a significant negative correlation was found between decreased ReHo in the right superior frontal gyrus and the delayed recall in GHR subjects. Our findings revealed decreased local function and hyper-connectivity in the fronto-limbic-striatal system of the DMN in GHR subjects, which is associated with cognitive deficits. This may improve our understanding of the neurophysiological endophenotypes of SCZ and the neural substrate underlying the cognitive deficits of the disease.
Collapse
Affiliation(s)
- Xiaoqian Ma
- Department of Psychiatry, Second Xiangya Hospital, Central South University, Changsha, China
| | - Wenxiao Zheng
- Department of Psychiatry, Second Xiangya Hospital, Central South University, Changsha, China; Department of Clinical Medicine, Third Xiangya Hospital, Central South University, Changsha, China
| | - Chunwang Li
- Department of Radiology, Hunan Children's Hospital, Changsha, China
| | - Zongchang Li
- Department of Psychiatry, Second Xiangya Hospital, Central South University, Changsha, China
| | - Jinsong Tang
- Department of Psychiatry, Second Xiangya Hospital, Central South University, Changsha, China
| | - Liu Yuan
- Department of Psychiatry, Second Xiangya Hospital, Central South University, Changsha, China
| | - Lijun Ouyang
- Department of Psychiatry, Second Xiangya Hospital, Central South University, Changsha, China
| | - Ke Jin
- Department of Radiology, Hunan Children's Hospital, Changsha, China
| | - Ying He
- Department of Psychiatry, Second Xiangya Hospital, Central South University, Changsha, China.
| | - Xiaogang Chen
- Department of Psychiatry, Second Xiangya Hospital, Central South University, Changsha, China; Mental Health Institute of Central South University, Changsha, Hunan, China; China National Clinical Research Center on Mental Disorders (Xiangya), Changsha, Hunan, China; China National Technology Institute on Mental Disorders, Changsha, Hunan, China; Hunan Key Laboratory of Psychiatry and Mental Health, Changsha, Hunan, China.
| |
Collapse
|
9
|
Behforuzi H, Feng NC, Billig AR, Ryan E, Tusch ES, Holcomb PJ, Mohammed AH, Daffner KR. Markers of Novelty Processing in Older Adults Are Stable and Reliable. Front Aging Neurosci 2019; 11:165. [PMID: 31316374 PMCID: PMC6611344 DOI: 10.3389/fnagi.2019.00165] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 06/13/2019] [Indexed: 12/21/2022] Open
Abstract
Exploratory behavior and responsiveness to novelty play an important role in maintaining cognitive function in older adults. Inferences about age- or disease-related differences in neural and behavioral responses to novelty are most often based on results from single experimental testing sessions. There has been very limited research on whether such findings represent stable characteristics of populations studied, which is essential if investigators are to determine the result of interventions aimed at promoting exploratory behaviors or draw appropriate conclusions about differences in the processing of novelty across diverse clinical groups. The goal of the current study was to investigate the short-term test-retest reliability of event-related potential (ERP) and behavioral responses to novel stimuli in cognitively normal older adults. ERPs and viewing durations were recorded in 70 healthy older adults participating in a subject-controlled visual novelty oddball task during two sessions occurring 7 weeks apart. Mean midline P3 amplitude and latency, mean midline amplitude during successive 50 ms intervals, temporospatial factors derived from principal component analysis (PCA), and viewing duration in response to novel stimuli were measured during each session. Analysis of variance (ANOVA) revealed no reliable differences in the value of any measurements between Time 1 and 2. Intraclass correlation coefficients (ICCs) between Time 1 and 2 were excellent for mean P3 amplitude (ICC = 0.86), the two temporospatial factors consistent with the P3 components (ICC of 0.88 and 0.76) and viewing duration of novel stimuli (ICC = 0.81). Reliability was only fair for P3 peak latency (ICC = 0.56). Successive 50 ms mean amplitude measures from 100 to 1,000 ms yielded fair to excellent reliabilities, and all but one of the 12 temporospatial factors identified demonstrated ICCs in the good to excellent range. We conclude that older adults demonstrate substantial stability in ERP and behavioral responses to novel visual stimuli over a 7-week period. These results suggest that older adults may have a characteristic way of processing novelty that appears resistant to transient changes in their environment or internal states, which can be indexed during a single testing session. The establishment of reliable measures of novelty processing will allow investigators to determine whether proposed interventions have an impact on this important aspect of behavior.
Collapse
Affiliation(s)
- Hura Behforuzi
- Laboratory of Healthy Cognitive Aging, Department of Neurology, Center for Brain/Mind Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Nicole C. Feng
- Laboratory of Healthy Cognitive Aging, Department of Neurology, Center for Brain/Mind Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Adam R. Billig
- Laboratory of Healthy Cognitive Aging, Department of Neurology, Center for Brain/Mind Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Eliza Ryan
- Laboratory of Healthy Cognitive Aging, Department of Neurology, Center for Brain/Mind Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Erich S. Tusch
- Laboratory of Healthy Cognitive Aging, Department of Neurology, Center for Brain/Mind Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| | - Phillip J. Holcomb
- Department of Psychology, San Diego State University, San Diego, CA, United States
| | - Abdul H. Mohammed
- Department of Psychology, Linnaeus University, Växjö, Sweden
- Department of Neurobiology, Care Sciences and Society, Division of Neurogeriatrics, Karolinska Institutet, Stockholm, Sweden
| | - Kirk R. Daffner
- Laboratory of Healthy Cognitive Aging, Department of Neurology, Center for Brain/Mind Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States
| |
Collapse
|
10
|
Knolle F, Ermakova AO, Justicia A, Fletcher PC, Bunzeck N, Düzel E, Murray GK. Brain responses to different types of salience in antipsychotic naïve first episode psychosis: An fMRI study. Transl Psychiatry 2018; 8:196. [PMID: 30242202 PMCID: PMC6154975 DOI: 10.1038/s41398-018-0250-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 06/16/2018] [Accepted: 07/24/2018] [Indexed: 02/07/2023] Open
Abstract
Abnormal salience processing has been suggested to contribute to the formation of positive psychotic symptoms in schizophrenia and related conditions. Previous research utilising reward learning or anticipation paradigms has demonstrated cortical and subcortical abnormalities in people with psychosis, specifically in the prefrontal cortex, the dopaminergic midbrain and the striatum. In these paradigms, reward prediction errors attribute motivational salience to stimuli. However, little is known about possible abnormalities across different forms of salience processing in psychosis patients, and whether any such abnormalities involve the dopaminergic midbrain. The aim of our study was, therefore, to investigate possible alterations in psychosis in neural activity in response to various forms of salience: novelty, negative emotion, targetness (task-driven salience) and rareness/deviance. We studied 14 antipsychotic naïve participants with first episode psychosis, and 37 healthy volunteers. During fMRI scanning, participants performed a visual oddball task containing these four forms of salience. Psychosis patients showed abnormally reduced signalling in the substantia nigra/ventral tegmental area (SN/VTA) for novelty, negative emotional salience and targetness; reduced striatal and occipital (lingual gyrus) signalling to novelty and negative emotional salience, reduced signalling in the amygdala, anterior cingulate cortex and parahippocamal gyrus to negative emotional salience, and reduced cerebellar signalling to novelty and negative emotional salience. Our results indicate alterations of several forms of salience processing in patients with psychosis in the midbrain SN/VTA, with additional subcortical and cortical regions also showing alterations in salience signalling, the exact pattern of alterations depending on the form of salience in question.
Collapse
Affiliation(s)
- Franziska Knolle
- Department of Psychiatry, University of Cambridge, Cambridge, UK.
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK.
| | - Anna O Ermakova
- Unit for Social & Community Psychiatry, WHO Collaborating Centre for Mental Health Services Development, East London NHS Foundation Trust, Cambridge, UK
| | - Azucena Justicia
- Unit for Social & Community Psychiatry, WHO Collaborating Centre for Mental Health Services Development, East London NHS Foundation Trust, Cambridge, UK
- IMIM (Hospital del Mar Medical Research Institute)., Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Barcelona, Spain
| | - Paul C Fletcher
- Unit for Social & Community Psychiatry, WHO Collaborating Centre for Mental Health Services Development, East London NHS Foundation Trust, Cambridge, UK
- Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK
- Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - Nico Bunzeck
- Institute of Psychology, University of Lübeck, Lübeck, Germany
| | - Emrah Düzel
- Otto-von-Guericke University Magdeburg, Institute of Cognitive Neurology and Dementia Research, Magdeburg, Germany
- German Centre for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Graham K Murray
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
- Unit for Social & Community Psychiatry, WHO Collaborating Centre for Mental Health Services Development, East London NHS Foundation Trust, Cambridge, UK
- Cambridgeshire and Peterborough NHS Foundation Trust, Cambridge, UK
| |
Collapse
|
11
|
Velichkovsky BM, Krotkova OA, Kotov AA, Orlov VA, Verkhlyutov VM, Ushakov VL, Sharaev MG. Consciousness in a multilevel architecture: Evidence from the right side of the brain. Conscious Cogn 2018; 64:227-239. [PMID: 29903632 DOI: 10.1016/j.concog.2018.06.004] [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: 01/29/2018] [Revised: 06/02/2018] [Accepted: 06/04/2018] [Indexed: 12/20/2022]
Abstract
By taking into account Bruce Bridgeman's interest in an evolutionary framing of human cognition, we examine effective (cause-and-effect) connectivity among cortical structures related to different parts of the triune phylogenetic stratification: archicortex, paleocortex and neocortex. Using resting-state functional magnetic resonance imaging data from 25 healthy subjects and spectral Dynamic Causal Modeling, we report interactions among 10 symmetrical left and right brain areas. Our results testify to general rightward and top-down biases in excitatory interactions of these structures during resting state, when self-related contemplation prevails over more objectified conceptual thinking. The right hippocampus is the only structure that shows bottom-up excitatory influences extending to the frontopolar cortex. The right ventrolateral cortex also plays a prominent role as it interacts with the majority of nodes within and between evolutionary distinct brain subdivisions. These results suggest the existence of several levels of cognitive-affective organization in the human brain and their profound lateralization.
Collapse
Affiliation(s)
- Boris M Velichkovsky
- National Research Center "Kurchatov Institute", Moscow, Russia; M.V. Lomonosov Moscow State University, Moscow, Russia; Russian State University for the Humanities, Moscow, Russia; Moscow Institute for Physics and Technology, Moscow, Russia; Technische Universitaet Dresden, Germany.
| | | | - Artemy A Kotov
- National Research Center "Kurchatov Institute", Moscow, Russia; Russian State University for the Humanities, Moscow, Russia
| | | | - Vitaly M Verkhlyutov
- Institute of the Higher Nervous Activity and Neurophysiology of the RAS, Moscow, Russia
| | - Vadim L Ushakov
- National Research Center "Kurchatov Institute", Moscow, Russia; National Nuclear Research University "MEPhI", Moscow, Russia
| | - Maxim G Sharaev
- Skolkovo Institute of Science and Technology, Skolkovo, Moscow Region, Russia
| |
Collapse
|
12
|
Gill KM, Miller SA, Grace AA. Impaired contextual fear-conditioning in MAM rodent model of schizophrenia. Schizophr Res 2018; 195:343-352. [PMID: 28927551 PMCID: PMC5854517 DOI: 10.1016/j.schres.2017.08.064] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 08/31/2017] [Accepted: 08/31/2017] [Indexed: 12/19/2022]
Abstract
The methylazoxymethanol acetate (MAM) rodent neurodevelopmental model of schizophrenia exhibits aberrant dopamine system activation attributed to hippocampal dysfunction. Context discrimination is a component of numerous behavioral and cognitive functions and relies on intact hippocampal processing. The present study explored context processing behaviors, along with dopamine system activation, during fear learning in the MAM model. Male offspring of dams treated with MAM (20mg/kg, i.p.) or saline on gestational day 17 were used for electrophysiological and behavioral experiments. Animals were tested on the immediate shock fear conditioning paradigm, with either different pre-conditioning contexts or varying amounts of context pre-exposure (0-10 sessions). Amphetamine-induced locomotor activity and dopamine neural activity was measured 1-week after fear conditioning. Saline, but not MAM animals, demonstrated enhanced fear responses following a single context pre-exposure in the conditioning context. One week following fear learning, saline rats with 2 or 7min of context pre-exposure prior to fear conditioning also demonstrated enhanced amphetamine-induced locomotor response relative to MAM animals. Dopamine neuron recordings showed fear learning-induced reductions in spontaneous dopamine neural activity in MAM rats that was further reduced by amphetamine. Apomorphine administration confirmed that reductions in dopamine neuron activity in MAM animals resulted from over excitation, or depolarization block. These data show a behavioral insensitivity to contextual stimuli in MAM rats that coincide with a less dynamic dopamine response after fear learning.
Collapse
Affiliation(s)
- Kathryn M Gill
- University of Pittsburgh, Pittsburgh, PA 15260, Departments of Neuroscience, Psychiatry and Psychology, USA.
| | - Sarah A Miller
- University of Pittsburgh, Pittsburgh, PA 15260, Departments of Neuroscience, Psychiatry and Psychology, USA
| | - Anthony A Grace
- University of Pittsburgh, Pittsburgh, PA 15260, Departments of Neuroscience, Psychiatry and Psychology, USA
| |
Collapse
|
13
|
Altered activation and connectivity in a hippocampal-basal ganglia-midbrain circuit during salience processing in subjects at ultra high risk for psychosis. Transl Psychiatry 2017; 7:e1245. [PMID: 28972591 PMCID: PMC5682600 DOI: 10.1038/tp.2017.174] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 05/08/2017] [Accepted: 06/01/2017] [Indexed: 12/21/2022] Open
Abstract
Animal models of psychosis propose that abnormal hippocampal activity drives increased subcortical dopamine function, which is thought to contribute to aberrant salience processing and psychotic symptoms. These effects appear to be mediated through connections between the hippocampus, ventral striatum/pallidum and the midbrain. The aim of the present study was to examine the activity and connectivity in this pathway in people at ultra high risk (UHR) for psychosis. Functional magnetic resonance imaging was used to compare neural responses in a hippocampal-basal ganglia-midbrain network during reward, novelty and aversion processing between 29 UHR subjects and 32 healthy controls. We then investigated whether effective connectivity within this network is perturbed in UHR subjects, using dynamic causal modelling (DCM). Finally, we examined the relationship between alterations in activation and connectivity in the UHR subjects and the severity of their psychotic symptoms. During reward anticipation, UHR subjects showed greater activation than controls in the ventral pallidum bilaterally. There were no differences in activation during novelty or aversion processing. DCM revealed that reward-induced modulation of connectivity from the ventral striatum/pallidum to the midbrain was greater in UHR subjects than controls, and that in UHR subjects, the strength of connectivity in this pathway was correlated with the severity of their abnormal beliefs. In conclusion, ventral striatal/pallidal function is altered in people at UHR for psychosis and this is related to the level of their psychotic symptoms.
Collapse
|
14
|
Huang X, Pu W, Li X, Greenshaw AJ, Dursun SM, Xue Z, Liu H, Liu Z. Decreased Left Putamen and Thalamus Volume Correlates with Delusions in First-Episode Schizophrenia Patients. Front Psychiatry 2017; 8:245. [PMID: 29209237 PMCID: PMC5702009 DOI: 10.3389/fpsyt.2017.00245] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 11/06/2017] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Delusional thinking is one of the hallmark symptoms of schizophrenia. However, the underlying neural substrate for delusions in schizophrenia remains unknown. In an attempt to further our understanding of the neural basis of delusions, we explored gray matter deficits and their clinical associations in first-episode schizophrenia patients with and without delusions. METHODS Twenty-four first-episode schizophrenia patients with delusions and 18 without delusions as well as 26 healthy controls (HC) underwent clinical assessment and whole-brain structural imaging which were acquired a 3.0 T scanner. Voxel-based morphometry was used to explore inter-group differences in gray matter volume using analysis of covariance, and Spearman correlation coefficients (rho) between the Scale for the Assessment of Positive Symptoms (SAPS)-delusion scores and mean regional brain volumes was obtained. RESULTS Patients with delusions showed decreased brain gray matter volumes in the left putamen, thalamus, and caudate regions compared with HC. Patients with delusions also showed decreased regional volume in the left putamen and thalamus compared with patients without delusions. SAPS-delusion scores were negatively correlated with the gray matter volumes of the left putamen and thalamus. DISCUSSION Left putamen and thalamus volume loss may be biological correlates of delusions in schizophrenia.
Collapse
Affiliation(s)
- Xiaojun Huang
- Mental Health Institute of the Second Xiangya Hospital, Central South University, Changsha, China.,The China National Clinical Research Center for Mental Health Disorders, National Technology Institute of Psychiatry, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Changsha, China
| | - Weidan Pu
- Medical Psychological Institute, Second Xiangya Hospital, Central South University, Changsha, China
| | - Xinmin Li
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
| | | | - Serdar M Dursun
- Department of Psychiatry, University of Alberta, Edmonton, AB, Canada
| | - Zhimin Xue
- Mental Health Institute of the Second Xiangya Hospital, Central South University, Changsha, China.,The China National Clinical Research Center for Mental Health Disorders, National Technology Institute of Psychiatry, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Changsha, China
| | - Haihong Liu
- Mental Health Center of Xiangya Hospital, Central South University, Changsha, China
| | - Zhening Liu
- Mental Health Institute of the Second Xiangya Hospital, Central South University, Changsha, China.,The China National Clinical Research Center for Mental Health Disorders, National Technology Institute of Psychiatry, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Changsha, China
| |
Collapse
|
15
|
Oestreich LKL, Pasternak O, Shenton ME, Kubicki M, Gong X, McCarthy-Jones S, Whitford TJ. Abnormal white matter microstructure and increased extracellular free-water in the cingulum bundle associated with delusions in chronic schizophrenia. NEUROIMAGE-CLINICAL 2016; 12:405-14. [PMID: 27622137 PMCID: PMC5008040 DOI: 10.1016/j.nicl.2016.08.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 07/01/2016] [Accepted: 08/03/2016] [Indexed: 12/22/2022]
Abstract
Background There is growing evidence to suggest that delusions associated with schizophrenia arise from altered structural brain connectivity. The present study investigated whether structural changes in three major fasciculi that interconnect the limbic system – the cingulum bundle, uncinate fasciculus and fornix – are associated with delusions in chronic schizophrenia patients. Methods Free-water corrected Diffusion Tensor Imaging was used to investigate the association between delusions and both microstructural changes within these three fasciculi and extracellular changes in the surrounding free-water. Clinical data and diffusion MRI scans were obtained from 28 healthy controls and 86 schizophrenia patients, of whom 34 had present state delusions, 35 had a lifetime history but currently remitted delusions, and 17 had never experienced delusions. Results While present state and remitted delusions were found to be associated with reduced free-water corrected fractional anisotropy (FAT) and increased free-water corrected radial diffusivity (RDT) in the cingulum bundle bilaterally, extracellular free-water (FW) in the left cingulum bundle was found to be specifically associated with present state delusions in chronic schizophrenia. No changes were observed in the remaining tracts. Conclusions These findings suggest that state and trait delusions in chronic schizophrenia are associated with microstructural processes, such as myelin abnormalities (as indicated by decreased FAT and increased RDT) in the cingulum bundle and that state delusions are additionally associated with extracellular processes such as neuroinflammation or atrophy (as indicated by increased FW) in the left cingulum bundle. Free-water imaging was used to differentiate microstructural and extracellular processes. Patients with delusions showed increased RDT and FW in the cingulum bundle. Myelin abnormalities and neuroinflammation may be involved in the manifestation of delusions.
Collapse
Affiliation(s)
- Lena K L Oestreich
- School of Psychology, UNSW Australia, NSW, Australia; Queensland Brain Institute, University of Queensland, St Lucia, QLD 4072, Australia
| | - Ofer Pasternak
- Department of Psychiatry, Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Martha E Shenton
- Department of Psychiatry, Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; VA Boston Healthcare System, Boston, MA, USA
| | - Marek Kubicki
- Department of Psychiatry, Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Xue Gong
- Department of Psychiatry, Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | | | - Simon McCarthy-Jones
- Department of Cognitive Science, Macquarie University, NSW, Australia; Department of Psychiatry, Trinity College Dublin, Ireland
| | | |
Collapse
|