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1.
Psychiatry Res Neuroimaging ; 340: 111803, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38460393

RESUMO

Adverse childhood experiences (ACEs) negatively affect the function and structure of emotion brain circuits, increasing the risk of various psychiatric disorders. It is unclear if ACEs show disorder specificity with respect to their effects on brain structure. We aimed to investigate whether the structural brain effects of ACEs differ between patients with major depression (MDD) and borderline personality disorder (BPD). These disorders share many symptoms but likely have different etiologies. To achieve our goal, we obtained structural 3T-MRI images from 20 healthy controls (HC), 19 MDD patients, and 18 BPD patients, and measured cortical thickness and subcortical gray matter volumes. We utilized the Adverse Childhood Experiences (ACE) questionnaire to quantify self-reported exposure to childhood trauma. Our findings suggest that individuals with MDD exhibit a smaller cortical thickness when compared to those with BPD. However, ACEs showed a significantly affected relationship with cortical thickness in BPD but not in MDD. ACEs were found to be associated with thinning in cortical regions involved in emotional behavior in BPD, whereas HC showed an opposite association. Our results suggest a potential mechanism of ACE effects on psychopathology involving changes in brain structure. These findings highlight the importance of early detection and intervention strategies.


Assuntos
Experiências Adversas da Infância , Transtorno da Personalidade Borderline , Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/patologia , Depressão , Encéfalo , Personalidade
2.
Proc Natl Acad Sci U S A ; 120(20): e2218782120, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37155867

RESUMO

Gender inequality across the world has been associated with a higher risk to mental health problems and lower academic achievement in women compared to men. We also know that the brain is shaped by nurturing and adverse socio-environmental experiences. Therefore, unequal exposure to harsher conditions for women compared to men in gender-unequal countries might be reflected in differences in their brain structure, and this could be the neural mechanism partly explaining women's worse outcomes in gender-unequal countries. We examined this through a random-effects meta-analysis on cortical thickness and surface area differences between adult healthy men and women, including a meta-regression in which country-level gender inequality acted as an explanatory variable for the observed differences. A total of 139 samples from 29 different countries, totaling 7,876 MRI scans, were included. Thickness of the right hemisphere, and particularly the right caudal anterior cingulate, right medial orbitofrontal, and left lateral occipital cortex, presented no differences or even thicker regional cortices in women compared to men in gender-equal countries, reversing to thinner cortices in countries with greater gender inequality. These results point to the potentially hazardous effect of gender inequality on women's brains and provide initial evidence for neuroscience-informed policies for gender equality.


Assuntos
Encéfalo , Equidade de Gênero , Masculino , Adulto , Humanos , Feminino , Encéfalo/diagnóstico por imagem , Fatores Sexuais
3.
Schizophr Res ; 254: 42-53, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36801513

RESUMO

Recent functional imaging studies in schizophrenia consistently report a disruption of brain connectivity. However, most of these studies analyze the brain connectivity during resting state. Since psychological stress is a major factor for the emergence of psychotic symptoms, we sought to characterize the brain connectivity reconfiguration induced by stress in schizophrenia. We tested the hypothesis that an alteration of the brain's integration-segregation dynamic could be the result of patients with schizophrenia facing psychological stress. To this end, we studied the modular organization and the reconfiguration of networks induced by a stress paradigm in forty subjects (twenty patients and twenty controls), thus analyzing the dynamics of the brain in terms of integration and segregation processes by using 3T-fMRI. Patients with schizophrenia did not show statistically significant differences during the control task compared with controls, but they showed an abnormal community structure during stress condition and an under-connected reconfiguration network with a reduction of hub nodes, suggesting a deficit of integration dynamic with a greater compromise of the right hemisphere. These results provide evidence that schizophrenia has a normal response to undemanding stimuli but shows a disruption of brain functional connectivity between key regions involved in stress response, potentially leading to altered functional brain dynamics by reducing integration capacity and showing deficits recruiting right hemisphere regions. This could in turn underlie the hyper-sensitivity to stress characteristic of schizophrenia.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Rede Nervosa , Encéfalo , Mapeamento Encefálico , Imageamento por Ressonância Magnética/métodos , Estresse Psicológico/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem
4.
Psychiatry Res Neuroimaging ; 318: 111394, 2021 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-34673383

RESUMO

Adverse childhood experiences (ACEs) have lifelong effects on emotional behavior and are frequent in Borderline Personality Disorder (BPD) and Major Depressive Disorder (MDD). The Central Autonomic Network (CAN), which modulates heart rate variability (HRV), comprises brain regions that mediate emotion regulation processes. However, it remains unclear the effect of ACEs on CAN dynamics and its relationship with HRV in these disorders. We studied the effects of ACEs on the brain and HRV simultaneously, during regulation of psychological stress in 19 BPD, 20 MDD and 20 healthy controls (HC). Participants underwent a cognitive reappraisal task during fMRI with simultaneous ECG acquisition. ACEs exposure was associated with increased activity of CAN and salience network components in patients with MDD compared to BPD during cognitive reappraisal. A brain-autonomic coupling was found in BPD relative to HC during emotion regulation, whereby greater activity of left anterior cingulate and medial superior frontal gyrus areas was coupled with increased HRV. Results suggest that ACEs exposure is associated with a distinct activation of the CAN and salience network regions governing responses to psychological stress in MDD compared to BPD. These alterations may constitute a distinctive neurobiological mechanism for abnormal emotion processing and regulation related to ACEs in MDD.


Assuntos
Experiências Adversas da Infância , Transtorno da Personalidade Borderline , Transtorno Depressivo Maior , Transtorno da Personalidade Borderline/psicologia , Cognição , Transtorno Depressivo Maior/diagnóstico por imagem , Emoções/fisiologia , Humanos
5.
Eur Psychiatry ; 64(1): e56, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34465401

RESUMO

BACKGROUND: One common denominator to the clinical phenotypes of borderline personality disorder (BPD) and major depressive disorder (MDD) is emotion regulation impairment. Although these two conditions have been extensively studied separately, it remains unclear whether their emotion regulation impairments are underpinned by shared or distinct neurobiological alterations. METHODS: We contrasted the neural correlates of negative emotion regulation across an adult sample of BPD patients (n = 19), MDD patients (n = 20), and healthy controls (HCs; n = 19). Emotion regulation was assessed using an established functional magnetic resonance imaging cognitive reappraisal paradigm. We assessed both task-related activations and modulations of interregional connectivity. RESULTS: When compared to HCs, patients with BPD and MDD displayed homologous decreased activation in the right ventrolateral prefrontal cortex (vlPFC) during cognitive reappraisal. In addition, the MDD group presented decreased activations in other prefrontal areas (i.e., left dorsolateral and bilateral orbitofrontal cortices), while the BPD group was characterized by a more extended pattern of alteration in the connectivity between the vlPFC and cortices of the visual ventral stream during reappraisal. CONCLUSIONS: This study identified, for the first time, a shared neurobiological contributor to emotion regulation deficits in MDD and BPD characterized by decreased vlPFC activity, although we also observed disorder-specific alterations. In MDD, results suggest a primary deficit in the strength of prefrontal activations, while BPD is better defined by connectivity disruptions between the vlPFC and temporal emotion processing regions. These findings substantiate, in neurobiological terms, the different profiles of emotion regulation alterations observed in these disorders.


Assuntos
Transtorno da Personalidade Borderline , Transtorno Depressivo Maior , Transtorno da Personalidade Borderline/diagnóstico por imagem , Cognição , Transtorno Depressivo Maior/diagnóstico por imagem , Emoções , Humanos , Imageamento por Ressonância Magnética
6.
Psychiatry Res Neuroimaging ; 316: 111342, 2021 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-34365076

RESUMO

A traditional hallmark of cognitive impairment associated with late-onset Alzheimer´s disease (LOAD) is episodic memory impairment. However, early alterations have been identified in brain regions associated with executive function in asymptomatic, middle-age offspring of patients with LOAD (O-LOAD) compared to those with no family history. We hypothesized that executive function among O-LOAD would correlate with structural and amyloid brain imaging differently from those without a family history of LOAD (control subjects, CS). Executive function, cortical thickness, and in-vivo Aß deposits were quantified in 30 O-LOAD and 25 CS. Associations were observed among O-LOAD only. Cortical thickness in the left lateral orbitofrontal cortex was positively associated with Design Fluency. The Stroop Color and Word Test, correlated positively with right rostral mid-frontal cortex thickness. Trails Making Test-B was inversely related to left medial orbitofrontal thickness. Tower of London total time was positively associated with ß-amyloid deposition in the right precuneus. These results support previous evidence that early executive dysfunction might reflect subtle, early changes in persons at risk of LOAD and suggests that executive function alterations deserve further exploration in the LOAD literature.


Assuntos
Doença de Alzheimer , Memória Episódica , Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Função Executiva , Humanos , Tomografia por Emissão de Pósitrons
7.
J Affect Disord ; 286: 123-133, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33721739

RESUMO

BACKGROUND: Major depressive disorder (MDD) and borderline personality disorder (BPD) are highly prevalent and often comorbid psychiatric conditions, with abnormal processing of negative affect resulting from psychological stress. Characteristics of central processing of autonomic response to stress in each disorder are not clearly settled. METHODS: We obtained whole brain 3T fMRI with concurrent skin conductance, respiration rate, and heart rate variability measures in a cohort of MDD (N=19), BPD (N=19) patients, and healthy (N=20) individuals. Experiments were conducted in resting conditions, during a control mental arithmetic task, during highly stressful mental arithmetic, and in the period immediately following psychological stress. RESULTS: Widespread activation of central autonomic network (CAN) structures was observed during stress compared to a control task in the group of healthy participants, whereas CAN activation during stress was less intense in both BPD and MDD. Both patient groups displayed increased sympathetic and decreased parasympathetic activation compared to healthy subjects, as previously reported. The relationship between peripheral sympathetic or parasympathetic activity and simultaneous regional brain BOLD activity was similar in BPD patients and healthy subjects, and markedly different from that seen in MDD patients. LIMITATIONS: The sample size, the fact it belonged to a single study site, and low grade affective symptomatology in both patient groups limit the generalizability of the present findings. CONCLUSIONS: The diverging neurobiological signature in the homeostatic response to stress in MDD and BPD possibly represents a heuristically valuable candidate biomarker to help discern MDD and BPD patients.


Assuntos
Transtorno da Personalidade Borderline , Transtorno Depressivo Maior , Encéfalo/diagnóstico por imagem , Depressão , Humanos , Imageamento por Ressonância Magnética
8.
Br J Psychiatry ; 218(2): 112-118, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32807243

RESUMO

BACKGROUND: Social and environmental factors such as poverty or violence modulate the risk and course of schizophrenia. However, how they affect the brain in patients with psychosis remains unclear. AIMS: We studied how environmental factors are related to brain structure in patients with schizophrenia and controls in Latin America, where these factors are large and unequally distributed. METHOD: This is a multicentre study of magnetic resonance imaging in patients with schizophrenia and controls from six Latin American cities. Total and voxel-level grey matter volumes, and their relationship with neighbourhood characteristics such as average income and homicide rates, were analysed with a general linear model. RESULTS: A total of 334 patients with schizophrenia and 262 controls were included. Income was differentially related to total grey matter volume in both groups (P = 0.006). Controls showed a positive correlation between total grey matter volume and income (R = 0.14, P = 0.02). Surprisingly, this relationship was not present in patients with schizophrenia (R = -0.076, P = 0.17). Voxel-level analysis confirmed that this interaction was widespread across the cortex. After adjusting for global brain changes, income was positively related to prefrontal cortex volumes only in controls. Conversely, the hippocampus in patients with schizophrenia, but not in controls, was relatively larger in affluent environments. There was no significant correlation between environmental violence and brain structure. CONCLUSIONS: Our results highlight the interplay between environment, particularly poverty, and individual characteristics in psychosis. This is particularly important for harsh environments such as low- and middle-income countries, where potentially less brain vulnerability (less grey matter loss) is sufficient to become unwell in adverse (poor) environments.


Assuntos
Esquizofrenia , Encéfalo/diagnóstico por imagem , Cidades , Substância Cinzenta , Humanos , América Latina/epidemiologia , Imageamento por Ressonância Magnética , Pobreza , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/epidemiologia , Violência
9.
J Psychiatr Res ; 130: 128-136, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32818661

RESUMO

Emotion perception is impaired in schizophrenia patients (SP) and related to reduced social skills performance. There is a remarkable variability across subjects for functional neuroimaging alterations related to this phenomenon. In contrast to the univariate approaches of fMRI, Multivariate Pattern Analysis (MVPA) maintains the within-subject voxel-level variability. The purpose of this study was to assess emotion processing in SP, in previously identified ROIs -i.e. amygdala, hippocampus, insula, and thalamus-, while retaining the functional heterogeneity that may exist between subjects. We evaluated 23 SP and 23 healthy controls (HC). Happy, sad, and neutral faces were presented. A single trial fMRI model was applied. Patterns of activation within each ROI were classified at the subject level. Within each group, stimuli classification scores were tested against random label classification scores. In ROIs with significant results, a whole ROI classification was performed, to test whether en bloc stimuli discrimination was present. A between-group analysis was conducted also. For the classification of stimuli above chance, in the HC results were significant in the left insula in all of the stimuli dichotomies, but were non-significant in SP for happy vs. sad. In whole ROI classification, SP had significant results in bilateral insular cortex for happy vs. neutral. The left amygdala showed diminished stimuli classification scores in SP for sad vs. neutral. In conclusion, MVPA seems useful to study emotional processing in schizophrenia. In SP, either en bloc or no stimuli discrimination was seen in the insula, and reduced stimuli discrimination was seen in the left amygdala.


Assuntos
Emoções , Imageamento por Ressonância Magnética , Esquizofrenia , Psicologia do Esquizofrênico , Tonsila do Cerebelo/diagnóstico por imagem , Mapeamento Encefálico , Expressão Facial , Hipocampo , Humanos , Esquizofrenia/diagnóstico por imagem
10.
J Psychiatr Res ; 123: 81-88, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32044590

RESUMO

Prevention and early treatment strategies for Alzheimer's disease (AD) are hampered by the lack of research biomarkers. Neuropathological changes in the Locus Coeruleus (LC) are detected early in AD, and noradrenaline plays a neuroprotective role in LC projecting areas. We assessed functional connectivity (FC) of the brainstem in asymptomatic individuals at familial risk for AD hypothesizing that FC of the LC will be decreased in relation to not-at-risk individuals. Thirty-one offspring of patients with late-onset AD (O-LOAD) (22 females; mean age ± SD = 50.36 ± 8.32) and 28 healthy controls (HC) (20 females; mean age ± SD = 53.90 ± 8.44) underwent a neurocognitive evaluation and a resting-state functional magnetic resonance imaging acquisition. In FC analyses we evaluated whole-brain global connectivity of the brainstem area, and subsequently assessed seed-to-voxel FC patterns from regions showing between-group differences. O-LOAD individuals scored worse in neurocognitive measures of memory and overall functioning (pFDR<0.05). In imaging analyses, we observed that O-LOAD individuals showed decreased global connectivity in a cluster encompassing the left LC (peak = -4, -34, -32, pTFCE<0.05). Seed-to-voxel analyses revealed that this finding was largely explained by decreased connectivity between the LC and the cerebellar cortex. Moreover, FC between the LC and the left cerebellum correlated positively with delayed recall scores. FC between the LC and the cerebellar cortex is decreased in the healthy offspring of patients with LOAD, such connectivity measurements being associated with delayed memory scores. The assessment of FC between the LC and the cerebellum may serve as a biomarker of AD vulnerability.


Assuntos
Doença de Alzheimer , Adulto , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Encéfalo , Feminino , Humanos , Locus Cerúleo , Imageamento por Ressonância Magnética , Pais
11.
J Psychiatr Res ; 122: 79-87, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31931231

RESUMO

Tau accumulation affecting white matter tracts is an early neuropathological feature of late-onset Alzheimer's disease (LOAD). There is a need to ascertain methods for the detection of early LOAD features to help with disease prevention efforts. The microstructure of these tracts and anatomical brain connectivity can be assessed by analyzing diffusion MRI (dMRI) data. Considering that family history increases the risk of developing LOAD, we explored the microstructure of white matter through dMRI in 23 cognitively normal adults who are offspring of patients with Late-Onset Alzheimer's Disease (O-LOAD) and 22 control subjects (CS) without family history of AD. We also evaluated the relation of white matter microstructure metrics with cortical thickness, volumetry, in vivo amyloid deposition (with the help of PiB positron emission tomography -PiB-PET) and regional brain metabolism (as FDG-PET) measures. Finally we studied the association between cognitive performance and white matter microstructure metrics. O-LOAD exhibited lower fiber density and fractional anisotropy in the posterior portion of the corpus callosum and right fornix when compared to CS. Among O-LOAD, reduced fiber density was associated with lower amyloid deposition in the right hippocampus, and greater cortical thickness in the left precuneus, while higher mean diffusivity was related with greater cortical thickness of the right superior temporal gyrus. Additionally, compromised white matter microstructure was associated with poorer semantic fluency. In conclusion, white matter microstructure metrics may reveal early differences in O-LOAD by virtue of parental history of the disorder, when compared to CS without a family history of LOAD. We demonstrate that these differences are associated with lower fiber density in the posterior portion of the corpus callosum and the right fornix.


Assuntos
Doença de Alzheimer , Substância Branca , Adulto , Doença de Alzheimer/diagnóstico por imagem , Anisotropia , Encéfalo/diagnóstico por imagem , Humanos , Tomografia por Emissão de Pósitrons , Substância Branca/diagnóstico por imagem
12.
J Neuropsychiatry Clin Neurosci ; 31(1): 25-36, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30305005

RESUMO

Failure to recover from proactive semantic interference (frPSI) has been shown to be more sensitive than traditional cognitive measures in different populations with preclinical Alzheimer's disease. The authors sought to characterize the structural and amyloid in vivo correlates of frPSI in cognitively normal offspring of patients with late-onset Alzheimer's disease (O-LOAD), compared with individuals without a family history of neurodegenerative disorders (CS). The authors evaluated the LASSI-L, a test tapping frPSI and other types of semantic interference and delayed recall on the RAVLT, along with 3-T MRI volumetry and positron emission tomography Pittsburgh compound B, in 27 O-LOAD and 18 CS with equivalent age, sex, years of education, ethnicity, premorbid intelligence, and mood symptoms. Recovery from proactive semantic interference (frPSI) and RAVLT delayed recall were lower in O-LOAD cases. Structural correlates of both cognitive dimensions were different in CS and O-LOAD, involving brain regions concerned with autonomic, motor, and motivational control in the former, and regions traditionally implicated in Alzheimer's disease in the latter. Better recovery from retroactive semantic interference was associated with less amyloid load in the left temporal lobe in O-LOAD but not CS. In middle-aged cognitively normal individuals with one parent affected with LOAD, frPSI was impaired compared with persons without a family history of LOAD. The neuroimaging correlates of such cognitive measure in those with one parent with LOAD involve Alzheimer's-relevant brain regions even at a relatively young age.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides/metabolismo , Encéfalo , Disfunção Cognitiva , Predisposição Genética para Doença , Rememoração Mental/fisiologia , Adulto , Idade de Início , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Compostos de Anilina , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Estudos Transversais , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Tomografia por Emissão de Pósitrons , Tiazóis , Adulto Jovem
13.
J Psychiatr Res ; 107: 11-18, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30308328

RESUMO

The natural history of preclinical late-onset Alzheimer's disease (LOAD) remains obscure and has received less attention than that of early-onset AD (EOAD), in spite of accounting for more than 99% of cases of AD. With the purpose of detecting early structural and functional traits associated with the disorder, we sought to characterize cortical thickness and subcortical grey matter volume, cerebral metabolism, and amyloid deposition in persons at risk for LOAD in comparison with a similar group without family history of AD. We obtained 3T T1 images for gray matter volume, FDG-PET to evaluate regional cerebral metabolism, and PET-PiB to detect fibrillar amyloid deposition in 30 middle-aged, asymptomatic, cognitively normal individuals with one parent diagnosed with LOAD (O-LOAD), and 25 comparable controls (CS) without family history of neurodegenerative disorders (CS). We observed isocortical thinning in AD-relevant areas including posterior cingulate, precuneus, and areas of the prefrontal and temporoparietal cortex in O-LOAD. Unexpectedly, this group displayed increased cerebral metabolism, in some cases overlapping with the areas of cortical thinning, and no differences in bilateral hippocampal volume and hippocampal metabolism. Given the importance of age in this sample of individuals potentially developing early AD-related changes, we controlled results for age and observed that most differences in cortical thickness and metabolism became nonsignificant; however, greater deposition of ß-amyloid was observed in the right hemisphere including temporoparietal cortex, postcentral gyrus, fusiform inferior and middle temporal and lingual gyri. If replicated, the present observations of morphological, metabolic, and amyloid changes in cognitively normal persons with family history of LOAD may bear important implications for the definition of very early phenotypes of this disorder.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides/metabolismo , Córtex Cerebral , Substância Cinzenta , Adulto , Filhos Adultos , Idade de Início , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/metabolismo , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons
14.
J Alzheimers Dis ; 60(3): 1183-1193, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28984601

RESUMO

BACKGROUND: We have obtained previous evidence of limbic dysfunction in middle-aged, asymptomatic offspring of late-onset Alzheimer's disease (LOAD) patients, and failure to recover from proactive semantic interference has been shown to be a sensitive cognitive test in other groups at risk for LOAD. OBJECTIVE: To assess the effects of specific proactive semantic interference deficits as they relate to functional magnetic resonance imaging (fMRI) neocortical and limbic functional connectivity in middle aged offspring of individuals with LOAD (O-LOAD) and age-equivalent controls. METHODS: We examined 21 O-LOAD and 20 controls without family history of neurodegenerative disorders (CS) on traditional measures of cognitive functioning and the LASSI-L, a novel semantic interference test uniquely sensitive to the failure to recover from proactive interference (frPSI). Cognitive tests then were correlated to fMRI connectivity of seeds located in entorhinal cortex and anterodorsal thalamic nuclei among O-LOAD and CS participants. RESULTS: Relative to CS, O-LOAD participants evidenced lower connectivity between entorhinal cortex and orbitofrontal, anterior cingulate, and anterior temporal cortex. In the offspring of LOAD patients, LASSI-L measures of frPSI were inversely associated with connectivity between anterodorsal thalamus and contralateral posterior cingulate. Intrusions on the task related to frPSI were inversely correlated with a widespread connectivity network involving hippocampal, insular, posterior cingulate, and dorsolateral prefrontal cortices, along with precunei and anterior thalamus in this group. Different patterns of connectivity associated with frPSI were observed among controls. CONCLUSION: The present results suggest that both semantic interference deficits and connectivity abnormalities might reflect limbic circuit dysfunction as a very early clinical signature of LOAD pathology, as previously demonstrated for other limbic phenotypes, such as sleep and circadian alterations.


Assuntos
Doença de Alzheimer/diagnóstico , Doença de Alzheimer/fisiopatologia , Cognição , Predisposição Genética para Doença , Sistema Límbico/fisiopatologia , Filhos Adultos , Idade de Início , Doença de Alzheimer/genética , Doença de Alzheimer/psicologia , Mapeamento Encefálico , Estudos Transversais , Feminino , Humanos , Sistema Límbico/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Testes Neuropsicológicos , Sintomas Prodrômicos , Semântica
16.
J Psychiatr Res ; 56: 120-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24927685

RESUMO

Measures of social competence are closely related to actual community functioning in patients with schizophrenia. However, the neurobiological mechanisms underlying competence in schizophrenia are not fully understood. We hypothesized that social deficits in schizophrenia are explained, at least in part, by abnormally lateralized patterns of brain activation in response to tasks engaging social cognition, as compared to healthy individuals. We predicted such patterns would be partly heritable, and therefore affected in patients' nonpsychotic siblings as well. We used a functional magnetic resonance image paradigm to characterize brain activation induced by theory of mind tasks, and two tests of social competence, the Test of Adaptive Behavior in Schizophrenia (TABS), and the Social Skills Performance Assessment (SSPA) in siblings discordant for schizophrenia and comparable healthy controls (n = 14 per group). Healthy individuals showed the strongest correlation between social competence and activation of right hemisphere structures involved in social cognitive processing, whereas in patients, the correlation pattern was lateralized to left hemisphere areas. Unaffected siblings of patients exhibited a pattern intermediate between the other groups. These results support the hypothesis that schizophrenia may be characterized by an abnormal functioning of nondominant hemisphere structures involved in the processing of socially salient information.


Assuntos
Encéfalo/fisiopatologia , Cognição/fisiologia , Esquizofrenia/fisiopatologia , Irmãos , Comportamento Social , Habilidades Sociais , Adulto , Mapeamento Encefálico , Estudos de Casos e Controles , Feminino , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Psicologia do Esquizofrênico , Teoria da Mente
17.
J Psychiatr Res ; 47(6): 774-82, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23403281

RESUMO

Moral decision-making involves complex social cognitive processes which are known to be altered in patients with schizophrenia and first-degree relatives. Traditional philosophical views on human moral behavior have distinguished between utilitarian views (which emphasize outcomes) and deontological approaches (defining what is right to do according to certain norms). Since emotions have been suggested to play a determining role in moral behavior, we hypothesized patients with schizophrenia and unaffected siblings would make more utilitarian choices and show faulty activation of brain areas concerned with emotion regulation during such tasks. Unexpectedly, all participants (n = 13 per group) made the same proportion of utilitarian and deontological decisions. Brain activation common to all groups induced by moral decisions included two circumscribed portions of right ventromedial and dorsolateral prefrontal cortex, adding to previous evidence on a right prosencephalic cognitive network involved in ethical decisions. However, brain activation induced by moral decisions was different in healthy persons, schizophrenia patients, and nonpsychotic siblings in regards to areas directly concerned with emotion processing. These results seem to underscore the role of acquired norms in moral decisions, a frequently overlooked concept in the neurobiological characterization of human ethical behavior, and add to previous evidence of abnormal social cognitive processing in schizophrenia.


Assuntos
Princípios Morais , Córtex Pré-Frontal/fisiopatologia , Esquizofrenia/fisiopatologia , Percepção Social , Adulto , Tomada de Decisões/fisiologia , Emoções/fisiologia , Feminino , Lateralidade Funcional/fisiologia , Neuroimagem Funcional , Humanos , Masculino , Testes Neuropsicológicos , Psicologia do Esquizofrênico , Irmãos
18.
Schizophr Res ; 134(2-3): 171-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22137736

RESUMO

BACKGROUND: Social cognitive deficits contribute to functional disability in schizophrenia. Social cognitive tasks in healthy persons consistently evoke activation of medial prefrontal cortex, inferior frontal gyrus, temporoparietal gyrus, and posterior cingulate cortex/precuneus. We tested the hypothesis that patients with schizophrenia and their unaffected siblings share dysfunction of the same neural networks. METHODS: Neural activation during emotion processing (EP), theory of mind (ToM), and control tasks was measured using functional magnetic resonance imaging (fMRI) in 14 patients with schizophrenia, 14 nonpsychotic siblings of patients with schizophrenia, and 14 matched healthy subjects. RESULTS: Compared with healthy controls, patients with schizophrenia showed reduced activation of right hemisphere structures involved in EP and ToM including inferior frontal gyrus, middle frontal gyrus, and right temporoparietal junction. These deficits were shared, in part, by unaffected siblings. The latter group demonstrated deficits in bilateral precuneus activation during ToM, not present in patients. CONCLUSIONS: Schizophrenia appears to be associated with a deficit in activation of right hemisphere components of a ToM network. Such deficits are shared in part by those at high genetic risk but unaffected by schizophrenia.


Assuntos
Encéfalo/patologia , Transtornos Cognitivos/etiologia , Lateralidade Funcional/fisiologia , Esquizofrenia/complicações , Psicologia do Esquizofrênico , Irmãos , Comportamento Social , Adulto , Análise de Variância , Encéfalo/irrigação sanguínea , Emoções , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Oxigênio/sangue , Reconhecimento Visual de Modelos , Escalas de Graduação Psiquiátrica , Tempo de Reação , Esquizofrenia/patologia , Teoria da Mente , Adulto Jovem
19.
Cogn Behav Neurol ; 24(4): 194-203, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22123585

RESUMO

OBJECTIVE: The objective of the study was to determine whether patients with schizophrenia and their unaffected first-degree relatives have abnormal autonomic nervous system (ANS) responses to social cognition tasks. BACKGROUND: Social cognition impairments are significant in schizophrenia. ANS activity has been shown to be abnormal in schizophrenia patients, and some of the abnormalities seem to be shared by patients' unaffected relatives. METHOD: Heart rate variability (HRV) was measured at rest and during social cognition tasks, in patients with schizophrenia, their nonpsychotic first-degree relatives, and matched healthy controls (n=19 in each group). RESULTS: Social cognition tasks induced a shortening of the RR interval in unaffected relatives, but not in patients. Social cognition tasks generated decreases in high-frequency (indicating cardiac vagal activity) and low-frequency (reflecting predominantly sympathetic activity) HRV in patients. In relatives, the decrease occurred in the high-frequency component only. Low-frequency HRV was higher in patients during a theory of mind task than a control task. These changes were not observed in the controls. CONCLUSIONS: Social cognitive tasks induce a pattern of peripheral autonomic activity different from that seen in generic arousal responses, and this pattern is abnormal in schizophrenia patients. Autonomic abnormalities in unaffected first-degree relatives seem restricted to the parasympathetic division of the ANS.


Assuntos
Transtornos Cognitivos/psicologia , Família/psicologia , Esquizofrenia/fisiopatologia , Psicologia do Esquizofrênico , Adulto , Idoso , Sistema Nervoso Autônomo/fisiopatologia , Estudos de Casos e Controles , Transtornos Cognitivos/complicações , Transtornos Cognitivos/fisiopatologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes Psicológicos/estatística & dados numéricos , Desempenho Psicomotor/fisiologia
20.
Neuropsychologia ; 48(5): 1209-15, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20026084

RESUMO

Previous studies have suggested that social cognition is affected in individuals with schizophrenia. The purpose of this study was to explore to what extent social cognition deficits are shared by unaffected first-degree relatives, and the nature of the relationship between performance in different paradigms of social cognition. 20 Schizophrenia patients (7 females, 31+/-10 years), 20 healthy age- and gender-matched individuals, 20 unaffected first-degree relatives of the schizophrenia patients (11 females, 50+/-20 years), and 20 healthy individuals matched for age and gender were recruited. Patients showed deficits in the detection of social Faux Pas (0.80+/-0.17 vs. controls: 0.94+/-0.09, p=0.025) and the correct identification of Theory of Mind stories (0.71+/-0.13 vs. controls: 0.82+/-0.12, p=0.038). Relatives performed poorly in the Faces Test (0.83+/-0.14 vs. controls: 0.9+/-0.08, p=0.048), the Reading the Mind in the Eyes Test (0.59+/-0.17 vs. controls: 0.71+/-0.14, p=0.046) and the detection of social Faux Pas (0.8+/-0.2 vs. controls: 0.93+/-0.09, p=0.024). Abnormalities were independent of age, years of education, and general cognitive performance in patients and their relatives. Performance in an Emotion Processing task (Faces Test) was correlated with performance in theory of mind tests in healthy individuals and relatives of patients with schizophrenia only. These results suggest that schizophrenia patients and their unaffected first-degree relatives display similar but nonidentical patterns of social cognition processing.


Assuntos
Afeto , Transtornos Cognitivos/epidemiologia , Família/psicologia , Esquizofrenia/epidemiologia , Percepção Social , Teoria da Mente , Transtornos Cognitivos/diagnóstico , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Esquizofrenia/diagnóstico , Índice de Gravidade de Doença
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