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1.
Psychiatry Res Neuroimaging ; 341: 111826, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38735228

RESUMO

We used a virtual navigation paradigm in a city environment to assess neuroanatomical correlates of cognitive deficits in schizophrenia spectrum disorders (SSD). We studied a total of N = 36 subjects: 18 with SSD and 18 matched unaffected controls. Participants completed 10 rapid, single-trial navigation tasks within the virtual city while undergoing functional magnetic resonance imaging (fMRI). All trials tested ability to find different targets seen earlier, during the passive viewing of a path around different city blocks. SSD patients had difficulty finding previously-encountered targets, were less likely to find novel shortcuts to targets, and more likely to attempt retracing of the path observed during passive viewing. Based on a priori region-of-interest analyses, SSD participants had hyperactivation of the left hippocampus when passively viewing turns, hyperactivation of the left caudate when finding targets, and hypoactivation of a focal area of the dorsolateral prefrontal cortex when targets were initially shown during passive viewing. We propose that these brain-behaviour relations may bias or reinforce stimulus-response navigation approaches in SSD and underlie impaired performance when allocentric spatial memory is required, such as when forming efficient shortcuts. This pattern may extend to more general cognitive impairments in SSD that could be used to design remediation strategies.

2.
Addict Behav ; 152: 107978, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38306868

RESUMO

BACKGROUND: Problematic cannabis use is associated with endorsement of psychotic-like experiences (PLEs) in non-clinical samples. However, little is known in regard to predictors of this relationship, which may be relevant to prevention and intervention. In the present research, we investigate impulsivity and cannabis use motives as potential distal and proximal risk factors for PLEs using conditional process analysis. METHODS: Using an online cross-sectional survey of N = 300 students, we assessed endorsement of PLEs using the Community Assessment of Psychic Experiences (CAPE), problematic cannabis use with the Cannabis Use Disorder Identification Test (CUDIT-R), motivations for using cannabis with the Substance Use Motives Measure, and impulsivity using the Urgency and Premeditation, Perseverance, Sensation Seeking, Positive Urgency Impulsive Behaviour Scale (UPPS-P). RESULTS: All three subscales on the CAPE were associated with significantly higher scores on the CUDIT-R. Before and after covarying for sex, we found that higher CUDIT-R scores mediated the relations between lack of perseverance and negative urgency impulsivity with higher PLE symptoms. Furthermore, the indirect effect of cannabis use on the relationship between lack of perseverance and high negative PLE symptoms was only significant at high and moderate levels of depression-coping, but not at low depression-coping motives. CONCLUSION: Impulsivity and depression-coping motives may be distal and proximal psychological risk factors for negative PLEs in the context of problematic cannabis use. Our findings are in line with the broader substance use and mental health literature and may be informative for cannabis use treatment targets.


Assuntos
Cannabis , Transtornos Relacionados ao Uso de Substâncias , Humanos , Estudos Transversais , Fatores de Risco , Transtornos Relacionados ao Uso de Substâncias/psicologia , Comportamento Impulsivo , Inquéritos e Questionários
3.
Drug Alcohol Depend ; 254: 111054, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38091900

RESUMO

BACKGROUND: Emerging adults who endorse more positive psychotic-like experiences (PLEs; bizarre experiences, delusional ideations) may experience greater cannabis-related impairments in executive function. Negative and depressive PLEs are also associated with cannabis use, however, less is known about their relation to executive functioning. Here, we hypothesize that high positive PLEs and cannabis use are associated with worse performance on computerized versions of the Iowa Gambling Task (IGT) and the Card Sorting Task (CST); exploratory analyses are conducted with negative and depressive PLEs. METHODS: We recruited university students (N = 543) who completed an online study consisting of self-report measures of problematic cannabis use (Cannabis Use Disorder Identification Test; CUDIT-R) and PLEs (Community Assessment of Psychotic Experiences; CAPE). Of these, n=270 completed the CST and n=251 completed the IGT. RESULTS: Problematic cannabis use and high endorsement of positive PLEs related to significantly worse performance on the IGT and greater perseverative errors on the CST. In addition, people who endorsed high levels of positive PLEs were also significantly more likely to complete the IGT with less money relative to those who endorsed fewer PLEs, regardless of cannabis use. Further analyses based on negative PLEs revealed a similar pattern for perseverative errors on the CST; depressive PLEs were not related to task performance. CONCLUSION: Findings highlight that problematic cannabis use and more frequent and distressing positive PLEs are associated with poorer executive functioning. Thus, executive functioning may have implications for intervention among those high on both attributes, who are at high risk of onset of psychosis.


Assuntos
Cannabis , Transtornos Psicóticos , Adulto , Humanos , Função Executiva , Autorrelato , Estudantes , Inquéritos e Questionários
4.
Exp Clin Psychopharmacol ; 32(2): 236-244, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37732959

RESUMO

Stereotype threat occurs when individuals from stigmatized groups feel they are expected to conform to a negative stereotype associated with their group. Studies show that activating stereotype threat can impair performance on cognitive tasks in various marginalized groups. Individuals with problematic alcohol use are subject to stigmatized views related to cognitive abilities and socialization skills; thus, we examine for the first time whether eliciting stereotype threat impairs performance on a memory and a theory of mind task in undergraduate students with varying drinking patterns. We randomized 205 students to a neutral or a stereotype threat condition, which informed participants that the purpose of the study was to assess memory performance and theory of mind skills in relation to different patterns of alcohol consumption. In the stereotype threat group, individuals with problematic drinking patterns demonstrated significantly worse memory performance than nonproblematic drinkers and nondrinkers. The same was not true in the neutral condition, where memory recall did not differ significantly as a function of drinking status. Experimental group and drinking status failed to reveal significant effects on cognitive and affective theory of mind performance. Problematic alcohol use patterns were only associated with poorer memory when stereotype threat was elicited, which indicates that assessments of neurocognitive profiles may be biased, at least for memory performance, if stereotype threat is inadvertently elicited in substance users. Broader implications support the imperative to avoid stigmatization of problematic substance use in scientific communication and clinical settings. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Cognição , Estereotipagem , Humanos , Memória , Transtornos da Memória/psicologia , Consumo de Bebidas Alcoólicas
5.
Memory ; 31(7): 948-961, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37189256

RESUMO

The mechanisms underlying a tendency among individuals with depression to report personal episodic memories with low specificity remain to be understood. We assessed a sample of undergraduate students with dysphoria to determine whether depression relates to a broader dysregulation of balancing accuracy and informativeness during memory reports. Specifically, we investigated metamnemonic processes using a quantity-accuracy profile approach. Recall involved three phases with increasing allowance for more general, or coarse-grained, responses: (a) forced-precise responding, requiring high precision; (b) free-choice report with high and low penalty incentives on accuracy; (c) a lexical description phase. Individuals with and without dysphoria were largely indistinguishable across indices of retrieval, monitoring, and control aspects of metamemory. The results indicate intact metacognitive processing in young individuals with dysphoria and provide no support for the view that impaired metacognitive control underlies either memory deficits or bias in memory reports that accompany dysphoria.


Assuntos
Transtorno Depressivo Maior , Memória Episódica , Metacognição , Humanos , Rememoração Mental/fisiologia , Metacognição/fisiologia , Transtornos da Memória
6.
J Affect Disord ; 325: 542-549, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36642312

RESUMO

BACKGROUND: A core cognitive attribute of depression is lower specificity in the expression of autobiographical memories. Despite interventions targeting memory specificity in depression, its underlying mechanisms are not yet fully understood. Depression also relates to poorer memory for episodic details; here we examine whether reduced specificity might simply reflect broader episodic memory deficits and weakened memory traces with the passage of time. METHODS: Undergraduate students with and without symptoms of depression completed the Autobiographical Interview and prose-reading episodic memory tasks to assess both same-day and delayed memory. RESULTS: Dysphoria and nondysphoria groups performed similarly on the tasks of immediate episodic and autobiographical memory; notably, the dysphoria group did not display evidence of lower specificity at this time point. After a delay, however, both groups demonstrated less specific memory responses on both memory tasks, and these declines were more pronounced in the group with dysphoria. That is, after a delay, individuals high in dysphoria showed a greater decrease in the quantity of specific event details reported on both the episodic and the autobiographical memory task. Additional analyses incorporating other clinical and cognitive measures indicated that these relations are largely unique to symptoms of depression. LIMITATIONS: The sample comprised mostly female students; the study should be replicated with more diverse samples. CONCLUSIONS: These findings support the claim that lower memory specificity is not peculiar to autobiographical memory, but rather, reflects impoverished memory more generally. This is an important consideration for theories and remedial strategies targeting memory specificity.


Assuntos
Transtorno Depressivo Maior , Memória Episódica , Humanos , Feminino , Masculino , Rememoração Mental/fisiologia , Transtornos da Memória/diagnóstico
7.
Emotion ; 23(6): 1764-1772, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36548052

RESUMO

Previous work has shown recognition of emotional facial expressions may differentially relate to task demands, such as whether one indirectly or directly encodes the emotional information. Given gender differences in emotion processing and memory, we assessed whether participant gender might moderate these encoding task effects. Using a between-subjects design with a sample of 100 undergraduates, participants made judgments about the gender (indirect) or emotion (direct) of facial stimuli displaying fearful, angry, happy, and neutral expressions. Different task-related effects were observed by gender for faces accompanied by recollection, as measured with the Remember-Know paradigm. Namely, women demonstrated better memory discrimination for emotional facial expressions only for remember responses following indirect encoding, whereas this effect was not significant for men. These results highlight the importance of considering participant gender, type of encoding task, and level of recollection on emotional memory for faces. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Ira , Emoções , Masculino , Humanos , Feminino , Emoções/fisiologia , Ira/fisiologia , Medo , Felicidade , Rememoração Mental , Expressão Facial
8.
Front Psychol ; 13: 998364, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36483715

RESUMO

Background: In this three-part study, we investigate whether the associations between binge and problematic drinking patterns with a negative emotional memory bias (NMB) are indirectly related through coping motivations and depressive symptoms. We also address potential sex differences in these relations. Methods: Participants (N = 293) completed the Timeline Followback to assess binge drinking, the Alcohol Use Disorder Identification Test (AUDIT) to assess problematic alcohol use, the Drinking Motives Questionnaire-Revised to assess coping motivations, and the Depression, Anxiety, and Stress Scales-21 to assess depression. Participants were asked to identify whether 30 emotional sentences were self-referent or not in an incidental encoding task; 24 h later they were asked to recall as many sentences as possible and a negative memory bias score was calculated. Results: Across all three studies, we found significant bivariate relations between AUDIT scores, coping, depression, and an NMB, particularly for sentences participants deemed self-referent. In two undergraduate samples, there were significant indirect effects through coping motivations and depressive symptoms between binge drinking and an NMB in females as well as between AUDIT scores and an NMB in females only. In the community sample, there was only an indirect effect through coping motives, but this was observed in both females and males. Conclusion: These findings support a relation between binge drinking as well as problematic alcohol use and a self-referent NMB in the context of coping motivations for alcohol use and depressive symptoms. Moreover, the pattern of findings suggests this model primarily holds for females, yet may also apply to males at higher levels of problematic alcohol use.

9.
Chronic Stress (Thousand Oaks) ; 6: 24705470221092428, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35465401

RESUMO

Posttraumatic stress disorder (PTSD) is a prevalent psychiatric disorder that can result from experiencing traumatic events. Accurate diagnosis and optimal treatment strategies can be difficult to achieve, due to the heterogeneous etiology and symptomology of PTSD, and overlap with other psychiatric disorders. Advancing our understanding of PTSD pathophysiology is therefore critical. While functional connectivity alterations have shown promise for elucidating the neurobiological mechanisms of PTSD, previous findings have been inconsistent. Eleven patients with PTSD in our first cohort (PTSD-A) and 11 trauma-exposed controls (TEC) underwent functional magnetic resonance imaging. First, we investigated the intrinsic connectivity within known resting state networks (eg, default mode, salience, and central executive networks) previously implicated in functional abnormalities with PTSD symptoms. Second, the overall topology of network structure was compared between PTSD-A and TEC using graph theory. Finally, we used a novel combination of graph theory analysis and scaled subprofile modeling (SSM) to identify a disease-related, covarying pattern of brain network organization. No significant group differences were found in intrinsic connectivity of known resting state networks and graph theory metrics (clustering coefficients, characteristic path length, smallworldness, global and local efficiencies, and degree centrality). The graph theory/SSM analysis revealed a topographical pattern of altered degree centrality differentiating PTSD-A from TEC. This PTSD-related network pattern expression was additionally investigated in a separate cohort of 33 subjects who were scanned with a different MRI scanner (22 patients with PTSD or PTSD-B, and 11 healthy trauma-naïve controls or TNC). Across all participant groups, pattern expression scores were significantly lower in the TEC group, while PTSD-A, PTSD-B, and TNC subject profiles did not differ from each other. Expression level of the pattern was correlated with symptom severity in the PTSD-B group. This method offers potential in developing objective biomarkers associated with PTSD. Possible interpretations and clinical implications will be discussed.

10.
J Psychiatr Res ; 146: 43-49, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34953304

RESUMO

Memory is better for emotional rather than neutral events or materials (emotional enhancement of memory; EEM). Evidence suggests that this memory benefit remains intact in schizophrenia, but conflicting findings present the need for further research to understand how and when this process occurs. Here, we examine whether different encoding methods for learning emotional faces may result in different EEM patterns in those with schizophrenia spectrum disorders (SSD). A patient group (n = 28) and healthy comparisons (n = 29) encoded faces in two conditions that manipulated attentional focus to promote direct (emotion judgements) or indirect (sex discrimination) processing of emotional content. Based on literature in schizophrenia showing selective emotion perception deficits on tasks of direct processing but relatively intact emotion perception on indirect processing tasks, we hypothesized that patients would show greater EEM effects when faces were encoded indirectly. This hypothesis was not supported, and the patient group instead showed a similar intact EEM for angry and fearful faces to healthy comparisons in both encoding conditions. Further, using the Remember/Know paradigm, we demonstrated that the EEM in SSD appears selective to recollection-based memory, which helps to explain inconsistencies in past literature that has not differentiated between recognition domains. These findings have important implications for improving emotional memory and functional outcomes in SSD; future research should establish how the EEM for facial expressions may relate to social functioning.


Assuntos
Expressão Facial , Esquizofrenia , Ira , Emoções , Humanos , Reconhecimento Psicológico , Esquizofrenia/complicações
11.
Biol Psychol ; 153: 107884, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32234502

RESUMO

Why are some people more religious than others? According to one hypothesis, people who strongly seek definitive explanations for situations with incomplete information are more likely to be religious. According to a different hypothesis, individuals with smaller "prediction error" responses to unexpected stimuli are more likely to discount evidence contradicting religious beliefs, predisposing them to maintain such beliefs. We sought neurophysiological evidence for these hypotheses using the N400 event-related potential (ERP), which is smaller to more contextually expected stimuli, reflecting prediction of probable completions for meaningful situations. We recorded ERPs from participants viewing category definitions followed by high-typicality category exemplar (HTE), low-typicality exemplar (LTE), or non-exemplar (NE) words. As expected, N400s were largest for NEs, intermediate for LTEs, and smallest for HTEs. Religiosity correlated with smaller N400 amplitude differences between HTEs and both LTEs and NEs. Less strong prediction of probable stimuli based on prior information may predispose to religiosity.


Assuntos
Encéfalo/fisiologia , Potenciais Evocados , Religião , Adolescente , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Religião e Psicologia , Semântica , Adulto Jovem
12.
CMAJ Open ; 8(1): E142-E147, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32161046

RESUMO

BACKGROUND: Insomnia is a major predictor of adverse outcomes in mild traumatic brain injury (mTBI), including concussion; although insomnia symptoms may be due to various sleep disorders, those related to circadian rhythm sleep-wake disorders (CRSWDs) require specific assessment and treatment. The objective of the current study was to determine the prevalence of CRSWD in a sample of treatment-seeking people with chronic insomnia symptoms after an mTBI. METHODS: Participants aged 17-65 years who had experienced an mTBI and reported chronic insomnia were recruited from diverse community clinics in Ontario 3-24 months after their injury to participate in this cross-sectional observational study. Potential participants were screened by both telephone and intake interview. Exclusion criteria were alcohol or substance use disorders, preexisting brain disorder or previous neurosurgery, recent travel across more than 2 time zones or shift work. Assessments included a clinical interview, questionnaires, 2 weeks of actigraphy and a sleep diary, and a dim-light melatonin onset test. The main outcome measure was the proportion of patients with CRSWDs. RESULTS: Of the 50 participants (32 [64%] female; median age 39.5 yr), 13 (26% [standard deviation 12%]) had an CRSWD. The most common circadian diagnosis was delayed sleep-wake phase disorder (10 participants [20%]). INTERPRETATION: The prevalence of CRSWDs may be exceptionally high among people with chronic insomnia symptoms following mTBI. Proper detection and treatment of CRSWDs in this population is essential to facilitate recovery. The findings emphasize the relevance of a diagnostic circadian assessment in patients with mTBI presenting with chronic insomnia symptoms.


Assuntos
Concussão Encefálica/complicações , Concussão Encefálica/epidemiologia , Ritmo Circadiano , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Transtornos do Sono do Ritmo Circadiano/diagnóstico , Transtornos do Sono do Ritmo Circadiano/epidemiologia , Transtornos do Sono do Ritmo Circadiano/etiologia , Distúrbios do Início e da Manutenção do Sono/diagnóstico , Distúrbios do Início e da Manutenção do Sono/etiologia , Inquéritos e Questionários , Adulto Jovem
13.
Neuropsychologia ; 141: 107395, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32142730

RESUMO

Repetitive transcranial magnetic stimulation (rTMS) is thought to modulate brain function through methods of electromagnetic induction. Over the last few decades, a large body of studies have investigated the clinical applications of rTMS in a variety of patient populations for a diverse range of symptoms from depressive symptomology to post-stroke motor functioning. There is still no clear consensus, however, on how rTMS influences cognitive functioning in the healthy brain. We conducted a quantitative meta-analysis in order to evaluate whether offline rTMS (the delivery of rTMS when not actively engaged in a cognitive task) influences cognition in healthy adults. More specifically, we examined studies that applied rTMS to the dorsal lateral prefrontal cortex (DLFPC) and that tracked cognitive outcomes both before and after a prescribed period of rTMS. Fifteen studies met our inclusion criteria. Cognitive performance was pooled and examined across studies for four cognitive domains (working memory, executive functioning, episodic memory, and visual perception) and under two types of stimulation conditions (excitatory and inhibitory rTMS). Whereas excitatory rTMS was associated with statistically reliable effects for improving executive functioning, inhibitory rTMS was associated with statistically reliable effects for improving episodic memory and visual perception. However, the magnitude of these effects was small and no other significant effects were observed. Though future studies are still needed, our findings suggest that offline forms of rTMS may have limited utility in affecting cognitive functioning when applied to the DLPFC in healthy adults, irrespective of cognitive domain or stimulation type.


Assuntos
Cognição , Estimulação Magnética Transcraniana , Adulto , Função Executiva , Humanos , Memória de Curto Prazo , Córtex Pré-Frontal
14.
Cyberpsychol Behav Soc Netw ; 23(2): 83-89, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32031895

RESUMO

Hoarding disorder is characterized by difficulty discarding objects and excessive clutter. The relationship between hoarding and claustrophobia, reactions to severely cluttered spaces, and clutter preferences are all areas that are yet to be investigated. The present study used a novel virtual reality (VR) platform to examine these domains. Two groups (i.e., with hoarding disorder, n = 36; without hoarding disorder, n = 40) similar in age and gender were recruited from the community. There were no differences in subjective or physiological reactivity to increasing VR clutter levels. The hoarding group reported a preference for slightly more cluttered VR rooms; however, they also reported higher claustrophobic fear. Results from this research advance our understanding of the relationship between hoarding symptoms and subjective experiences of clutter and offer implications for future VR research and treatment initiatives.


Assuntos
Transtorno de Acumulação/fisiopatologia , Transtornos Fóbicos/fisiopatologia , Realidade Virtual , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Psychiatry Res ; 278: 125-128, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31174032

RESUMO

Spatial memory is core to wayfinding and everyday memory. Interestingly, individuals with schizophrenia using spatial navigation strategies (cognitive mapping) are impaired, whereas those using response-based (e.g., single-landmark) strategies show relatively intact memory performance. We observed abnormal brain communication in schizophrenia participants who used a spatial strategy during a virtual-reality navigation task, particularly between temporal and frontal brain regions. In contrast, schizophrenia participants using a response strategy recruited similar brain systems to healthy participants, but to a greater extent to support memory performance. These findings highlight that strategy use is an important consideration for understanding memory systems and navigation in schizophrenia.


Assuntos
Lobo Frontal/fisiopatologia , Rede Nervosa/fisiopatologia , Esquizofrenia/fisiopatologia , Memória Espacial/fisiologia , Navegação Espacial/fisiologia , Lobo Temporal/fisiopatologia , Realidade Virtual , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Lobo Temporal/diagnóstico por imagem , Adulto Jovem
16.
Cogn Neuropsychiatry ; 23(4): 242-253, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29848232

RESUMO

Introduction Working-memory (WM) is a core cognitive deficit among individuals with Schizophrenia Spectrum Disorders (SSD). However, the underlying cognitive mechanisms of this deficit are less known. This study applies a modified version of the Corsi Block Test to investigate the role of proactive interference in visuospatial WM (VSWM) impairment in SSD. Methods Healthy and SSD participants completed a modified version of the Corsi Block Test involving both high (typical ascending set size from 4 to 7 items) and low (descending set size from 7 to 4 items) proactive interference conditions. Results The results confirmed that the SSD group performed worse overall relative to a healthy comparison group. More importantly, the SSD group demonstrated greater VSWM scores under low (Descending) versus high (Ascending) proactive interference; this pattern is opposite to that of healthy participants. Conclusions This differential pattern of performance supports that proactive interference associated with the traditional administration format contributes to VSWM impairment in SSD. Further research investigating associated neurocognitive mechanisms and the contribution of proactive interference across other domains of cognition in SSD is warranted.


Assuntos
Transtornos Cognitivos/fisiopatologia , Memória de Curto Prazo/fisiologia , Testes Neuropsicológicos/normas , Esquizofrenia/fisiopatologia , Memória Espacial/fisiologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
BMC Psychiatry ; 18(1): 129, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29764396

RESUMO

BACKGROUND: Posttraumatic stress disorder (PTSD) is associated with abnormal hippocampal activity; however, the functional connectivity (FC) of the hippocampus with other brain regions in PTSD and its relations with symptoms warrants further attention. We investigated subregional hippocampal FC in PTSD during a resting state compared with a trauma-exposed control (TEC) group. Based on extant research, we targeted the FCs of the anterior and posterior hippocampal subregions with the amygdala, medial prefrontal cortex (mPFC), and the posterior cingulate (PCC). METHODS: Resting-state functional magnetic resonance images were acquired from 11 individuals with PTSD and 13 trauma-exposed controls. Anterior and posterior hippocampal FC was compared between groups. Within the PTSD and TEC groups, subregional hippocampal FC was correlated with scores on the Clinician-Administered PTSD Scale (CAPS) at time of scan and 4 months post-scan. RESULTS: Those with PTSD had significantly greater FC compared with the TEC group between the left posterior hippocampus and the bilateral PCC (g's > .96). Direct contrasts of the Fisher z-transformed coefficients indicated that the correlations between CAPS scores 4 months post scan and the FC between the left hippocampal head and the right PCC (z = - 2.07, p = .039) as well as the FC between the right hippocampal tail and the right mPFC (z = - 2.19, p = .029) were significantly greater in the PTSD group compared to the TEC group. CONCLUSIONS: These results support between-group differences in posterior hippocampal FC and different relations with PTSD future symptoms, underscoring associations with the anterior and posterior hippocampus. These findings enrich our understanding of PTSD pathophysiology and provide support for future investigations of imaging biomarkers predictive of disease progression.


Assuntos
Hipocampo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Transtornos de Estresse Pós-Traumáticos/diagnóstico por imagem , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Mapeamento Encefálico , Estudos de Casos e Controles , Progressão da Doença , Feminino , Hipocampo/fisiopatologia , Humanos , Masculino , Descanso , Transtornos de Estresse Pós-Traumáticos/psicologia
18.
Neurorehabil Neural Repair ; 31(12): 1063-1071, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29153039

RESUMO

BACKGROUND: In the chronic stages of moderate-severe traumatic brain injury (TBI), progressive hippocampal volume loss-continuing well after acute neurological insults have resolved-has now been well documented. Previous research in other populations suggests that elevated anxiety symptoms are associated with compromise to the medial temporal lobes. OBJECTIVE: To examine whether higher anxiety symptoms predict greater hippocampal volume loss in moderate-severe TBI. METHODS: We conducted an analysis of prospectively collected, longitudinal behavioral and magnetic resonance imaging (MRI) data from 5 to 12 to 30 months post-injury. Eighty participants were included in the study, with anxiety symptom and MRI data collected at a minimum of 2 time points. Correlational and bivariate latent difference score (with imputation) analyses were used to examine the relationship of Beck Anxiety Inventory scores with hippocampal volume loss, while controlling for depressive symptoms and total brain volume. RESULTS: Analyses revealed that higher anxiety symptoms at 5 and at 12 months following moderate-severe TBI predicted significant later volume loss in the right hippocampal complex and the right hippocampal head. Right hippocampal volume and volume change did not predict subsequent anxiety scores or anxiety change scores. CONCLUSIONS: These novel findings implicate anxiety symptoms as a possible predictor of progressive hippocampal volume loss in the chronic stages of moderate-severe TBI.


Assuntos
Ansiedade/diagnóstico por imagem , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/psicologia , Hipocampo/diagnóstico por imagem , Adulto , Atrofia , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas Traumáticas/reabilitação , Doença Crônica , Progressão da Doença , Feminino , Lateralidade Funcional , Hipocampo/patologia , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão , Prognóstico , Estudos Prospectivos , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença
19.
Psychiatry Res Neuroimaging ; 268: 1-8, 2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-28780430

RESUMO

Different strategies may be spontaneously adopted to solve most navigation tasks. These strategies are associated with dissociable brain systems. Here, we use brain-imaging and cognitive tasks to test the hypothesis that individuals living with Schizophrenia Spectrum Disorders (SSD) have selective impairment using a hippocampal-dependent spatial navigation strategy. Brain activation and memory performance were examined using functional magnetic resonance imaging (fMRI) during the 4-on-8 virtual maze (4/8VM) task, a human analog of the rodent radial-arm maze that is amenable to both response-based (egocentric or landmark-based) and spatial (allocentric, cognitive mapping) strategies to remember and navigate to target objects. SSD (schizophrenia and schizoaffective disorder) participants who adopted a spatial strategy performed more poorly on the 4/8VM task and had less hippocampal activation than healthy comparison participants using either strategy as well as SSD participants using a response strategy. This study highlights the importance of strategy use in relation to spatial cognitive functioning in SSD. Consistent with a selective-hippocampal dependent deficit in SSD, these results support the further development of protocols to train impaired hippocampal-dependent abilities or harness non-hippocampal dependent intact abilities.


Assuntos
Hipocampo/fisiopatologia , Aprendizagem em Labirinto/fisiologia , Memória/fisiologia , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/fisiopatologia , Adulto , Encéfalo/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Navegação Espacial/fisiologia , Jogos de Vídeo/psicologia
20.
J Behav Ther Exp Psychiatry ; 56: 21-26, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27887704

RESUMO

BACKGROUND AND OBJECTIVES: Delusions of reference are thought to reflect abnormally heightened attributions of salience to mundane events or stimuli that lead to convictions that they are personally significant or directed at the observer. Recent findings highlight abnormal recruitment of brain regions associated with self-referential processes among patients with referential delusions. Given the inherent overlap of emotion, incentive salience, and self-relevance, as well as with aberrant thought processes in psychosis, this study investigated the implicit relations between participants' perception of the emotional valence of stimuli on neural correlates of self-referent judgments among schizophrenia-spectrum patients with referential delusions. METHODS: During fMRI scanning, participants indicated whether sentences describing personal characteristics seemed to refer specifically to them. Subsequently, participants rated their perceived emotional valence of each statement. RESULTS: Regression analyses revealed differential relations between groups across regions associated with self-referential processing, including prefrontal regions, anterior cingulate, insula, precuneus, and dorsal striatum. Within these regions, greater activation related to sentences rated as more positive among healthy comparison participants and more negative among patients. LIMITATIONS: The current results warrant replication and extension with larger and longitudinal samples to assess potential moderating relations of clinical and demographic individual differences. CONCLUSIONS: These findings support aberrant brain activation associated with emotional and salience brain networks in schizophrenia and highlight the importance of considering specific emotional attributes (valence) in discrete domains of delusional thought (self-referential communication).


Assuntos
Encéfalo/fisiopatologia , Delusões/fisiopatologia , Emoções/fisiologia , Giro do Cíngulo/fisiopatologia , Esquizofrenia/fisiopatologia , Autoimagem , Adulto , Estudos de Casos e Controles , Delusões/complicações , Feminino , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esquizofrenia/complicações , Psicologia do Esquizofrênico , Adulto Jovem
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