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1.
Eur J Neurosci ; 59(8): 1863-1876, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37160716

RESUMO

People with schizophrenia experience difficulties with social interactions. One contributor to these social deficits is dysfunction in processing facial features and facial emotional expressions. However, it is not known whether face processing deficits are evident in those with other psychotic disorders or in those genetically at-risk for psychosis (i.e., first-degree relatives of those with psychosis). We assessed event-related potentials (ERPs) during a facial and emotion processing task in 100 people with a diagnosis of schizophrenia or another psychotic condition (PSY), 32 of their siblings (SIB) and 45 healthy comparison participants (CTL). In separate blocks, participants identified the sex (male or female) or emotion (happy, angry, neutral) of faces. In a comparison condition, participants indicated whether buildings had one or two floors. ERPs were examined in two stages. First, we compared ERPs across the emotion, sex and building identification conditions. Second, we compared ERPs among the three different facial emotions. PSY exhibited significantly lower amplitudes over parietal-occipital regions between 111 and 151 ms when viewing faces but not buildings than CTL, consistent with a face-selective N170 ERP component deficit. The SIB group was intermediate for faces, but not significantly different than PSY or CTL. During emotion identification, all three groups showed increased N170 amplitudes to angry and happy versus neutral expressions, with no group differences. In follow up analyses, we examined differences between PSY with or without affective psychosis, and differences between those with schizophrenia versus other psychotic disorders; there were no significant differences in these analyses. Face processing deficits assessed with ERPs were observed in a group of diverse psychotic disorders, though deficits were not seen to be modulated by facial emotion expression. Additionally, N170 deficits are not evident in siblings of those with PSY.


Assuntos
Reconhecimento Facial , Transtornos Psicóticos , Humanos , Masculino , Feminino , Reconhecimento Facial/fisiologia , Eletroencefalografia , Irmãos , Potenciais Evocados/fisiologia , Transtornos Psicóticos/psicologia , Emoções/fisiologia , Expressão Facial
2.
Psychol Med ; 54(9): 2015-2023, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38314526

RESUMO

BACKGROUND: People with schizophrenia on average are more socially isolated, lonelier, have more social cognitive impairment, and are less socially motivated than healthy individuals. People with bipolar disorder also have social isolation, though typically less than that seen in schizophrenia. We aimed to disentangle whether the social cognitive and social motivation impairments observed in schizophrenia are a specific feature of the clinical condition v. social isolation generally. METHODS: We compared four groups (clinically stable patients with schizophrenia or bipolar disorder, individuals drawn from the community with self-described social isolation, and a socially connected community control group) on loneliness, social cognition, and approach and avoidance social motivation. RESULTS: Individuals with schizophrenia (n = 72) showed intermediate levels of social isolation, loneliness, and social approach motivation between the isolated (n = 96) and connected control (n = 55) groups. However, they showed significant deficits in social cognition compared to both community groups. Individuals with bipolar disorder (n = 48) were intermediate between isolated and control groups for loneliness and social approach. They did not show deficits on social cognition tasks. Both clinical groups had higher social avoidance than both community groups. CONCLUSIONS: The results suggest that social cognitive deficits in schizophrenia, and high social avoidance motivation in both schizophrenia and bipolar disorder, are distinct features of the clinical conditions and not byproducts of social isolation. In contrast, differences between clinical and control groups on levels of loneliness and social approach motivation were congruent with the groups' degree of social isolation.


Assuntos
Transtorno Bipolar , Solidão , Motivação , Esquizofrenia , Psicologia do Esquizofrênico , Cognição Social , Isolamento Social , Humanos , Transtorno Bipolar/psicologia , Transtorno Bipolar/fisiopatologia , Masculino , Feminino , Adulto , Isolamento Social/psicologia , Solidão/psicologia , Pessoa de Meia-Idade , Esquizofrenia/fisiopatologia , Comportamento Social
3.
Brain Behav Immun ; 120: 372-378, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38897331

RESUMO

BACKGROUND: Social isolation and loneliness (known as social disconnection, collectively) lead to serious downstream health effects, including shortening of lifespan and higher risk for cardiac disease. We must better understand how isolation and loneliness lead to these negative health outcomes. Previous literature has demonstrated that social motivation and social ability are contributors to the likelihood of social isolation and loneliness. We examined the effect of the above social factors on immune gene expression in socially-connected and -isolated individuals. METHODS: Recruitment occurred via two online advertisements, one for socially isolated individuals and another for general research participants. Participants (n = 102) were separated into groups (isolated versus connected) based on which ad they responded to, and provided data on isolation, loneliness, social motivation, and social ability. The Conserved Transcriptional Response to Adversity (CTRA) stress gene regulation program was assessed with genome-wide transcriptional profiling. RESULTS: CTRA gene expression patterns were reversed between connected and isolated groups across several variables. Social isolation was associated with higher CTRA levels in the connected group, but lower levels in the isolated group. Social approach was associated with lower CTRA levels in the connected group, but higher in the isolated group, and the converse was true for social avoidance. CTRA levels were minimally affected by social ability measures. CONCLUSION: Prior work on social isolation and loneliness has focused on loneliness and has identified many negative downstream health effects. In this study we demonstrate that objective social isolation may not be associated with the same negative downstream health effects, and in fact, social interaction may be more stressful than social isolation for some socially-isolated individuals.


Assuntos
Regulação da Expressão Gênica , Solidão , Isolamento Social , Estresse Psicológico , Humanos , Isolamento Social/psicologia , Masculino , Solidão/psicologia , Feminino , Estresse Psicológico/genética , Estresse Psicológico/metabolismo , Estresse Psicológico/psicologia , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Motivação
4.
Soc Psychiatry Psychiatr Epidemiol ; 59(1): 111-120, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37314492

RESUMO

PURPOSE: Mental health trajectories during the COVID-19 pandemic have been examined in Veterans with tenuous social connections, i.e., those with recent homelessness (RHV) or a psychotic disorder (PSY), and in control Veterans (CTL). We test potential moderating effects on these trajectories by psychological factors that may help individuals weather the socio-emotional challenges associated with the pandemic (i.e., 'psychological strengths'). METHODS: We assessed 81 PSY, 76 RHV, and 74 CTL over 5 periods between 05/2020 and 07/2021. Mental health outcomes (i.e., symptoms of depression, anxiety, contamination concerns, loneliness) were assessed at each period, and psychological strengths (i.e., a composite score based on tolerance of uncertainty, performance beliefs, coping style, resilience, perceived stress) were assessed at the initial assessment. Generalized models tested fixed and time-varying effects of a composite psychological strengths score on clinical trajectories across samples and within each group. RESULTS: Psychological strengths had a significant effect on trajectories for each outcome (ps < 0.05), serving to ameliorate changes in mental health symptoms. The timing of this effect varied across outcomes, with early effects for depression and anxiety, later effects for loneliness, and sustained effects for contamination concerns. A significant time-varying effect of psychological strengths on depressive symptoms was evident in RHV and CTL, anxious symptoms in RHV, contamination concerns in PSY and CTL, and loneliness in CTL (ps < 0.05). CONCLUSION: Across vulnerable and non-vulnerable Veterans, presence of psychological strengths buffered against exacerbations in clinical symptoms. The timing of the effect varied across outcomes and by group.


Assuntos
COVID-19 , Veteranos , Humanos , Saúde Mental , Pandemias , Emoções , Ansiedade/epidemiologia , Depressão/epidemiologia
5.
Psychol Med ; 52(1): 169-177, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-32517838

RESUMO

BACKGROUND: Little is known about the determinants of community integration (i.e. recovery) for individuals with a history of homelessness, yet such information is essential to develop targeted interventions. METHODS: We recruited homeless Veterans with a history of psychotic disorders and evaluated four domains of correlates of community integration: perception, non-social cognition, social cognition, and motivation. Baseline assessments occurred after participants were engaged in supported housing services but before they received housing, and again after 12 months. Ninety-five homeless Veterans with a history of psychosis were assessed at baseline and 53 returned after 12 months. We examined both cross-sectional and longitudinal relationships with 12-month community integration. RESULTS: The strongest longitudinal association was between a baseline motivational measure and social integration at 12 months. We also observed cross-sectional associations at baseline between motivational measures and community integration, including social, work, and independent living. Cross-lagged panel analyses did not suggest causal associations for the motivational measures. Correlations with perception and non-social cognition were weak. One social cognition measure showed a significant longitudinal correlation with independent living at 12 months that was significant for cross-lagged analysis, consistent with a causal relationship and potential treatment target. CONCLUSIONS: The relatively selective associations for motivational measures differ from what is typically seen in psychosis, in which all domains are associated with community integration. These findings are presented along with a partner paper (Study 2) to compare findings from this study to an independent sample without a history of psychotic disorders to evaluate the consistency in findings regarding community integration across projects.


Assuntos
Pessoas Mal Alojadas , Transtornos Psicóticos , Veteranos , Humanos , Integração Comunitária , Veteranos/psicologia , Motivação , Estudos Transversais , Transtornos Psicóticos/psicologia , Cognição
6.
Psychol Med ; 51(16): 2915-2922, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-32466807

RESUMO

BACKGROUND: In an initial study (Study 1), we found that motivation predicted community integration (i.e. functional recovery) 12 months after receiving housing in formerly homeless Veterans with a psychotic disorder. The current study examined whether the same pattern would be found in a broader, more clinically diverse, homeless Veteran sample without psychosis. METHODS: We examined four categories of variables as potential predictors of community integration in non-psychotic Veterans: perception, non-social cognition, social cognition, and motivation at baseline (after participants were engaged in a permanent supported housing program but before receiving housing) and a 12-month follow-up. A total of 82 Veterans had a baseline assessment and 41 returned for testing after 12 months. RESULTS: The strongest longitudinal association was between an interview-based measure of motivation (the motivation and pleasure subscale from the Clinical Assessment Interview for Negative Symptoms) at baseline and measures of social integration at 12 months. In addition, cross-lagged panel analyses were consistent with a causal influence of general psychiatric symptoms at baseline driving social integration at 12 months, and reduced expressiveness at baseline driving independent living at 12 months, but there were no significant causal associations with measures of motivation. CONCLUSIONS: The findings from this study complement and reinforce those in Veterans with psychosis. Across these two studies, our findings suggest that motivational factors are associated at baseline and at 12 months and are particularly important for understanding and improving community integration in recently-housed Veterans across psychiatric diagnoses.


Assuntos
Pessoas Mal Alojadas , Veteranos , Humanos , Veteranos/psicologia , Integração Comunitária , Motivação , Cognição
7.
Hum Brain Mapp ; 40(5): 1608-1617, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30575206

RESUMO

Functional magnetic resonance imaging (fMRI) adaptation (also known as fMRI repetition suppression) has been widely used to characterize stimulus selectivity in vivo, a fundamental feature of neuronal processing in the brain. We investigated whether SZ patients and BD patients show aberrant fMRI adaptation for object perception. About 52 SZ patients, 55 BD patients, and 53 community controls completed an object discrimination task with three conditions: the same object presented twice, two exemplars from the same category, and two exemplars from different categories. We also administered two functional localizer tasks. A region of interest analysis was employed to evaluate a priori hypotheses about the lateral occipital complex (LOC) and early visual cortex (EVC). An exploratory whole brain analysis was also conducted. In the LOC and EVC, controls showed the expected reduced fMRI responses to repeated presentation of the same objects compared with different objects (i.e., fMRI adaptation for objects, p < .001). SZ patients showed an adaptation effect that was significantly smaller compared with controls. BD patients showed a lack of fMRI adaptation. The whole brain analyses showed enhanced fMRI responses to repeated presentation of the same objects only in BD patients in several brain regions including anterior cingulate cortex. This study was the first to employ fMRI adaptation for objects in SZ and BD. The current findings provide empirical evidence of aberrant fMRI adaptation in the visual cortex in SZ and BD, but in distinctly different ways.


Assuntos
Adaptação Psicológica , Transtorno Bipolar/diagnóstico por imagem , Transtorno Bipolar/psicologia , Esquizofrenia/diagnóstico por imagem , Psicologia do Esquizofrênico , Adolescente , Adulto , Idoso , Transtorno Bipolar/fisiopatologia , Mapeamento Encefálico , Discriminação Psicológica , Feminino , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Lobo Occipital/diagnóstico por imagem , Lobo Occipital/fisiopatologia , Escalas de Graduação Psiquiátrica , Esquizofrenia/fisiopatologia , Córtex Visual/diagnóstico por imagem , Córtex Visual/fisiopatologia , Percepção Visual , Adulto Jovem
8.
Psychol Med ; 49(7): 1195-1206, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30642411

RESUMO

BACKGROUND: Mismatch negativity (MMN) is an event-related potential (ERP) component reflecting auditory predictive coding. Repeated standard tones evoke increasing positivity ('repetition positivity'; RP), reflecting strengthening of the standard's memory trace and the prediction it will recur. Likewise, deviant tones preceded by more standard repetitions evoke greater negativity ('deviant negativity'; DN), reflecting stronger prediction error signaling. These memory trace effects are also evident in MMN difference wave. Here, we assess group differences and test-retest reliability of these indices in schizophrenia patients (SZ) and healthy controls (HC). METHODS: Electroencephalography was recorded twice, 2 weeks apart, from 43 SZ and 30 HC, during a roving standard paradigm. We examined ERPs to the third, eighth, and 33rd standards (RP), immediately subsequent deviants (DN), and the corresponding MMN. Memory trace effects were assessed by comparing amplitudes associated with the three standard repetition trains. RESULTS: Compared with controls, SZ showed reduced MMNs and DNs, but normal RPs. Both groups showed memory trace effects for RP, MMN, and DN, with a trend for attenuated DNs in SZ. Intraclass correlations obtained via this paradigm indicated good-to-moderate reliabilities for overall MMN, DN and RP, but moderate to poor reliabilities for components associated with short, intermediate, and long standard trains, and poor reliability of their memory trace effects. CONCLUSION: MMN deficits in SZ reflected attenuated prediction error signaling (DN), with relatively intact predictive code formation (RP) and memory trace effects. This roving standard MMN paradigm requires additional development/validation to obtain suitable levels of reliability for use in clinical trials.


Assuntos
Atenção/fisiologia , Eletroencefalografia , Potenciais Evocados Auditivos/fisiologia , Rememoração Mental/fisiologia , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esquizofrenia/diagnóstico , Adulto Jovem
9.
Cereb Cortex ; 27(5): 2984-2993, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-27226446

RESUMO

Patients with schizophrenia show specific abnormalities in visual perception, and patients with bipolar disorder may have related perceptual deficits. During tasks that highlight perceptual dysfunction, patients with schizophrenia show abnormal activity in visual brain areas, including the lateral occipital complex (LOC) and early retinotopic cortex. It is unclear whether the anatomical structure of those visual areas is atypical in schizophrenia and bipolar disorder. In members of those two patient groups and healthy controls, we localized LOC and early retinotopic cortex individually for each participant using functional magnetic resonance imaging (MRI), then measured the thickness of those regions of interest using structural MRI scans. In both regions, patients with schizophrenia had the thinnest cortex, controls had the thickest cortex, and bipolar patients had intermediate cortical thickness. A control region, motor cortex, did not show this pattern of group differences. The thickness of each visual region of interest was significantly correlated with performance on a visual object masking task, but only in schizophrenia patients. These findings suggest an anatomical substrate for visual processing abnormalities that have been found with both neural and behavioral measures in schizophrenia and other severe mental illnesses.


Assuntos
Transtorno Bipolar/complicações , Esquizofrenia/complicações , Transtornos de Sensação/etiologia , Transtornos de Sensação/patologia , Córtex Visual/patologia , Percepção Visual/fisiologia , Adolescente , Adulto , Idoso , Transtorno Bipolar/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Oxigênio/sangue , Mascaramento Perceptivo , Estimulação Luminosa , Esquizofrenia/diagnóstico por imagem , Transtornos de Sensação/diagnóstico por imagem , Córtex Visual/diagnóstico por imagem , Adulto Jovem
10.
Scand J Psychol ; 59(1): 41-48, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29356009

RESUMO

Auditory hallucinations, a hallmark symptom of psychosis, are experienced by most people with a diagnosis of schizophrenia at some point in their illness. Auditory hallucinations can be understood as a failure in predictive coding, whereby abnormalities in sensory/perceptual processing combine with biased cognitive processes to result in a dampening of normal prediction error signaling. In this paper, we used a roving mismatch negativity (MMN) paradigm to optimize evaluation of prediction error signaling and short-term neuroplasticity in 30 people with schizophrenia (n = 16 with and n = 14 without recent auditory hallucinations) and 20 healthy comparison participants. The recent hallucinations group exhibited an abnormal roving MMN profile [F(2,27) = 3.98, p = 0.03], significantly reduced prediction error signaling [t(28) = -2.25, p = 0.03], and a trend for diminished short-term neuroplasticity [t(28) = 1.80, p = 0.08]. There were no statistically significant differences between the healthy comparison group and the combined schizophrenia group on any of the roving MMN indices. These findings are consistent with a predictive coding account of hallucinations in schizophrenia, which posits reduced prediction error signaling in those who are prone to hallucinations. These results also suggest that plasticity-mediated formation and online updating of predictive coding models may also be disrupted in individuals with recent hallucinations.


Assuntos
Encéfalo/fisiopatologia , Alucinações , Plasticidade Neuronal , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Estimulação Acústica , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
11.
Hum Brain Mapp ; 35(9): 4654-62, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24677632

RESUMO

Despite a well-known behavioral finding of visual backward masking impairment in schizophrenia, its underlying neural mechanism remains obscure. This study examined neural correlates of a distinct type of visual backward masking, object substitution masking (OSM), in schizophrenia. Twenty schizophrenia patients and 26 healthy controls completed a 4-Dot OSM task and three functional localizer tasks for the lateral occipital (LO), human motion-sensitive (hMT+), and retinotopic areas in the scanner. In 4-dot masking, subjects detected a target that was followed by a mask consisting of 4 dots that surrounded a target. Stimulus-onset asynchrony (SOA) between target and mask was varied to examine the modulation of masking: (1) within three visual processing areas regions of interest (ROI) (i.e., ROI analysis) and (2) in brain regions outside the three visual processing areas (i.e., whole brain analysis). In the ROI analyses, LO and retinotopic areas showed increased peak amplitude when SOA become longer in both patients and controls. There was also an effect of ROI in that both groups showed higher activation in LO and hMT+ compared with the retinotopic areas. The whole brain analyses revealed a significantly activated area for longer SOAs vs. a short SOA in the occipital cortex in controls only, but the group contrast was not significant. Overall, this study did not find strong evidence for neural abnormalities of OSM in schizophrenia, suggesting that neural substrates of OSM in schizophrenia are not as compromised as those involved in the more common masking methods that rely on disruption of object formation.


Assuntos
Encéfalo/fisiopatologia , Mascaramento Perceptivo/fisiologia , Esquizofrenia/fisiopatologia , Percepção Visual/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Humanos , Entrevista Psicológica , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Estimulação Luminosa , Psicologia do Esquizofrênico
12.
Cogn Affect Behav Neurosci ; 14(3): 1049-60, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24415272

RESUMO

Although schizophrenia is associated with impairments in social cognition, the scope and neural correlates of these disturbances are largely unknown. In this study, we investigated whether schizophrenia patients show impaired functioning of the mirror neuron system (MNS), as indexed by electroencephalographic (EEG) mu (8-13 Hz) suppression, a hypothesized biomarker of MNS activity that is sensitive to the degree of social interaction depicted in visual stimuli. A total of 32 outpatients and 26 healthy controls completed an EEG paradigm that included six action observation or execution conditions that differed in their degrees of social interaction. Participants also completed a validated empathy questionnaire. Across both groups, we found a significant linear increase in mu suppression across the conditions involving greater levels of social engagement and interaction, but no significant group or interaction effects. Patients self-reported diminished empathic concern and perspective taking, which showed some moderate relations to mu suppression levels. Thus, the schizophrenia group showed generally intact modulation of MNS functioning at the electrophysiological level, despite self-reporting empathic disturbances. The disturbances commonly seen on self-report, performance, and neuroimaging measures of mentalizing in schizophrenia may largely reflect difficulties with higher-level inferential processes about others' emotions, rather than a basic incapacity to share in these experiences.


Assuntos
Transtornos Cognitivos/etiologia , Emigração e Imigração , Empatia/fisiologia , Desempenho Psicomotor/fisiologia , Esquizofrenia/complicações , Psicologia do Esquizofrênico , Percepção Social , Adolescente , Adulto , Análise de Variância , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Adulto Jovem
13.
Cogn Neuropsychiatry ; 19(4): 319-36, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24397788

RESUMO

INTRODUCTION: Successful processing of multisensory stimuli increases the likelihood of detection or identification of salient, biologically significant events faster and more efficiently than unisensory inputs. Schizophrenia (SZ) patients show deficits in unisensory processing, but it is unclear whether impairments are seen to multisensory stimuli, a process known as multisensory integration (MSI). We used behavioural and event-related potential (ERP) measures to examine MSI in SZ and healthy controls (HC). METHODS: Thirty-three SZ and 30 HC completed a target detection task with unisensory and multisensory stimuli. Reaction times (RT) were measured while their electroencephalogram (EEG) was recorded. Two auditory (N100 and P200) and visual (P100 and N160) ERPs were examined. MSI was analysed in terms of violations of RT to the race model and by comparing ERPs in the MSI condition to the sum of the unisensory ERPs. RESULTS: Both groups showed faster RT in MSI compared to unisensory conditions. SZ had non-significantly fewer violations of the race model compared to HC. SZ had significantly smaller amplitudes to unisensory visual N160 and auditory P100 relative to HC; there were no significant group differences on any ERP measure of MSI. CONCLUSIONS: SZ showed relatively intact MSI with subtle (non-significant) differences at the neural and behavioural levels compared to HC. Our results suggest that neural processes associated with MSI are not an additional source of impairment in SZ.


Assuntos
Estimulação Acústica/métodos , Potenciais Evocados , Estimulação Luminosa/métodos , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Reação , Percepção Visual
14.
Clin EEG Neurosci ; 55(4): 445-454, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38711326

RESUMO

Despite different etiologies, people with schizophrenia (SCZ) or with traumatic brain injury (TBI) both show aberrant neuroplasticity. One neuroplastic mechanism that may be affected is prediction error coding. We used a roving mismatch negativity (rMMN) paradigm which uses different lengths of standard tone trains and is optimized to assess predictive coding. Twenty-five SCZ, 22 TBI (mild to moderate), and 25 healthy controls were assessed. We used a frequency-deviant rMMN in which the number of standards preceding the deviant was either 2, 6, or 36. We evaluated repetition positivity to the standard tone immediately preceding a deviant tone (repetition positivity [RP], to assess formation of the memory trace), deviant negativity to the deviant stimulus (deviant negativity [DN], which reflects signaling of a prediction error), and the difference wave between the 2 (the MMN). We found that SCZ showed reduced DN and MMN compared with healthy controls and with people with mild to moderate TBI. We did not detect impairments in any index (RP, DN, or MMN) in people with TBI compared to controls. Our findings suggest that prediction error coding assessed with rMMN is aberrant in SCZ but intact in TBI, though there is a suggestion that severity of head injury results in poorer prediction error coding.


Assuntos
Lesões Encefálicas Traumáticas , Eletroencefalografia , Plasticidade Neuronal , Esquizofrenia , Humanos , Masculino , Esquizofrenia/fisiopatologia , Feminino , Adulto , Eletroencefalografia/métodos , Plasticidade Neuronal/fisiologia , Lesões Encefálicas Traumáticas/fisiopatologia , Pessoa de Meia-Idade , Adulto Jovem
15.
Schizophr Res ; 272: 112-119, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39214021

RESUMO

Impaired visual target detection is a common finding in schizophrenia that is linked to poor functional outcomes. However, the neural mechanisms that contribute to this deficit remain unclear. Recent research in healthy samples has identified relationships between the phase of pre-stimulus electroencephalographic (EEG) activity in the alpha band (8-12 Hz) or theta band (4-7 Hz) and the likelihood of visual target detection with and without attentional cueing, but these effects have not yet been explored in schizophrenia. We performed a study to investigate such effects in schizophrenia (n = 19) and healthy participants (n = 14), using a visual target detection task with attentional cues. We found significant relationships between pre-stimulus EEG phase properties and visual target detection in both groups, but also clear differences in the effects as a function of frequency, group, and attentional cueing. Alpha-band phase effects were relatively uniform across groups and conditions. By contrast, theta-band phase effects showed differences by group and attentional condition which could be consistent with attentional hyperfocusing in the schizophrenia group. Thus, our results elucidate a novel neural mechanism that may help to explain known impairments affecting both visual target detection and attention in schizophrenia.


Assuntos
Atenção , Eletroencefalografia , Esquizofrenia , Humanos , Esquizofrenia/fisiopatologia , Esquizofrenia/diagnóstico , Masculino , Feminino , Adulto , Projetos Piloto , Atenção/fisiologia , Sinais (Psicologia) , Adulto Jovem , Percepção Visual/fisiologia , Estimulação Luminosa , Ritmo Teta/fisiologia , Pessoa de Meia-Idade
16.
Artigo em Inglês | MEDLINE | ID: mdl-38909899

RESUMO

BACKGROUND: Schizophrenia (SCZ) and bipolar disorder (BD) are associated with information processing abnormalities, including visual perceptual and cognitive impairments, that impact daily functioning. Recent work with healthy samples suggests that peak alpha frequency (PAF) is an electrophysiological index of visual information processing speed that is correlated with cognitive ability. There is evidence that PAF is slowed in SCZ, but it remains unclear whether PAF is reduced in BD or whether slower PAF is associated with impaired visual perception and cognition in these clinical disorders. METHODS: We recorded resting-state brain activity (both eyes open and closed) with electroencephalography in 90 participants with SCZ, 62 participants with BD, and 69 healthy control participants. Most participants also performed a visual perception task (backward masking) and cognitive testing (MATRICS Concensus Cognitive Battery). RESULTS: We replicated previous findings of reduced PAF in patients with SCZ compared with healthy control participants. In contrast, PAF in patients with BD did not differ significantly from that in healthy control participants. Furthermore, PAF was significantly correlated with performance on the perceptual and cognitive measures in SCZ but not BD. PAF was also correlated with visual perception in the healthy control group and showed a trend-level correlation with cognition. CONCLUSIONS: Together, these results suggest that PAF deficits characterize SCZ, but not BD, and that individual differences in PAF are related to abnormalities in visual information processing and cognition in SCZ.

17.
J Psychiatr Res ; 172: 102-107, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38373371

RESUMO

The COVID-19 pandemic disproportionately impacted marginalized populations including Black Americans, people with serious mental illness, and individuals experiencing homelessness. Although the double disadvantage hypothesis would suggest that individuals with multiple minoritized statuses would experience worse psychosocial impacts from the pandemic, this may not be the case for vulnerable Black Veterans. The present study investigated the sustained mental health and functional responses to the pandemic in Black and White Veterans with psychosis or recent homelessness and in a control group of Veterans enrolled in the Department of Veterans Affairs healthcare services. Clinical interviews and questionnaires were administered remotely by telephone at five time points from May 2020 through July 2021, including a retrospective time point for March 2020 (i.e., before the pandemic started). Overall, there was a striking absence of systematic differences by race in the trajectories of psychiatric symptoms and functioning among Veterans during the study period. These findings are consistent with a report on initial responses to the pandemic that revealed only a few select differences by race among Veteran groups. The lack of racial disparities is inconsistent with the double disadvantage hypothesis. Although further investigation is needed, one possible interpretation is that the wrap-around services offered by the Veterans Health Administration may have mitigated expected differences by race among Veterans with psychosis or homelessness. Future research should continue to examine whether VA services mitigate disparities in mental health and psychosocial outcomes.


Assuntos
COVID-19 , Pessoas Mal Alojadas , Transtornos Psicóticos , Veteranos , Estados Unidos/epidemiologia , Humanos , Saúde Mental , Pandemias , Estudos Retrospectivos , Brancos , United States Department of Veterans Affairs , Transtornos Psicóticos/epidemiologia
18.
Schizophrenia (Heidelb) ; 10(1): 88, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39368972

RESUMO

Social disconnection, including objective social isolation and subjective loneliness, is linked to substantial health risks. Yet, little is known about the predictors of social disconnection in individuals with mental illness. Here, we used machine learning to identify predictors of social isolation and loneliness in schizophrenia (N = 72), a psychiatric condition associated with social disconnection. For comparison, we also included two other groups: a psychiatric comparison sample of bipolar disorder (N = 48) and a community sample enriched for social isolation (N = 151). We fitted statistical models of social isolation and loneliness within and across groups. Each model included five candidate predictors: social avoidance motivation, depression, nonsocial cognition, social anhedonia, and social cognition. The results showed that social anhedonia explained unique variance in social isolation and loneliness in all samples, suggesting that it contributes to social isolation and loneliness broadly. However, nonsocial cognition explained unique variance in social isolation only within schizophrenia. Thus, social anhedonia could be a potential intervention target across populations, whereas nonsocial cognition may play a unique role in determining social disconnection in schizophrenia.

19.
Clin EEG Neurosci ; 55(4): 395-405, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38298008

RESUMO

People with schizophrenia (SCZ) and bipolar disorder (BD) have impairments in processing social information, including faces. The neural correlates of face processing are widely studied with the N170 ERP component. However, it is unclear whether N170 deficits reflect neural abnormalities associated with these clinical conditions or differences in social environments. The goal of this study was to determine whether N170 deficits would still be present in SCZ and BD when compared with socially isolated community members. Participants included 66 people with SCZ, 37 with BD, and 125 community members (76 "Community-Isolated"; 49 "Community-Connected"). Electroencephalography was recorded during a face processing task in which participants identified the gender of a face, the emotion of a face (angry, happy, neutral), or the number of stories in a building. We examined group differences in the N170 face effect (greater amplitudes for faces vs buildings) and the N170 emotion effect (greater amplitudes for emotional vs neutral expressions). Groups significantly differed in levels of social isolation (Community-Isolated > SCZ > BD = Community-Connected). SCZ participants had significantly reduced N170 amplitudes to faces compared with both community groups, which did not differ from each other. The BD group was intermediate and did not differ from any group. There were no significant group differences in the processing of specific emotional facial expressions. The N170 is abnormal in SCZ even when compared to socially isolated community members. Hence, the N170 seems to reflect a social processing impairment in SCZ that is separate from level of social isolation.


Assuntos
Transtorno Bipolar , Eletroencefalografia , Potenciais Evocados , Expressão Facial , Esquizofrenia , Isolamento Social , Humanos , Transtorno Bipolar/fisiopatologia , Masculino , Feminino , Eletroencefalografia/métodos , Adulto , Esquizofrenia/fisiopatologia , Potenciais Evocados/fisiologia , Pessoa de Meia-Idade , Isolamento Social/psicologia , Emoções/fisiologia , Reconhecimento Facial/fisiologia
20.
Psychol Serv ; 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37410791

RESUMO

The COVID-19 pandemic disproportionately impacted the physical health of some vulnerable groups, but further study is needed to investigate the pandemic's impact on financial health and mental well-being. We analyzed data from 158 participants, consisting of 59 veterans with a psychotic disorder (PSY), 49 recently housed veterans (RHV), and a control group of 50 veterans (CTL) who were assessed five times from May 2020-July 2021. This study compared the financial health of these three groups and examined the relation between financial health and psychiatric symptoms. Although the CTL group reported significantly higher income and savings than the PSY and RHV groups, the CTL group reported greater negative financial shocks than the PSY group. The RHV group reported greater material hardship but greater propensity to plan for finances and less financial shocks than the PSY group. Across all three groups, there was a reduction in financial shocks over time and no group showed more change than another. Across time, material hardship, financial shocks, and propensity to plan for finances were each significantly associated with symptoms of major depression. Together, these findings suggest the COVID-19 pandemic did not greatly impact the financial health of PSY and RHV groups possibly because of their limited income and resilience to adversity. Financial health was related to mental health supporting the U.S. government's strategic plan to include financial empowerment services in efforts to improve mental health and reduce veteran suicide. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

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