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Variability in brain structure is associated with the capacity for behavioral change. However, a causal link between specific brain areas and behavioral change (such as motor learning) has not been demonstrated. We hypothesized that greater gray matter volume of a primary motor cortex (M1) area active during a hand motor learning task is positively correlated with subsequent learning of the task, and that the disruption of this area blocks learning of the task. Healthy participants underwent structural MRI before learning a skilled hand motor task. Next, participants performed this learning task during fMRI to determine M1 areas functionally active during this task. This functional ROI was anatomically constrained with M1 boundaries to create a group-level "Active-M1" ROI used to measure gray matter volume in each participant. Greater gray matter volume in the left hemisphere Active-M1 ROI was related to greater motor learning in the corresponding right hand. When M1 hand area was disrupted with repetitive transcranial stimulation (rTMS), learning of the motor task was blocked, confirming its causal link to motor learning. Our combined imaging and rTMS approach revealed greater cortical volume in a task-relevant M1 area is causally related to learning of a hand motor task in healthy humans.
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Sustancia Gris , Mano , Aprendizaje , Imagen por Resonancia Magnética , Corteza Motora , Estimulación Magnética Transcraneal , Humanos , Corteza Motora/fisiología , Corteza Motora/diagnóstico por imagen , Masculino , Femenino , Mano/fisiología , Aprendizaje/fisiología , Adulto , Adulto Joven , Sustancia Gris/fisiología , Sustancia Gris/diagnóstico por imagen , Destreza Motora/fisiología , Mapeo Encefálico , Lateralidad Funcional/fisiologíaRESUMEN
BACKGROUND: Research examining the neural correlates of obesity has recently expanded. However, limited attention has focused on identifying unique brain signatures associated with obesity, particularly in adolescents. The aim of this study was to use surface-based approaches to examine the integrity of brain structures involved in processing the pleasurable effects of food with body mass and food reward sensitivity in adolescent girls. METHODS: Structural morphology of the nucleus accumbens, amygdala, pallidum, and orbitofrontal cortex was examined in 89 adolescent girls with body mass ranging from normal to obese. High-resolution T1-weighted MPRAGE images were used to characterize deep-brain nuclei with high-dimensional diffeomorphic mapping procedures, while cortical thickness was derived from the FreeSurfer toolkit. RESULTS: Results revealed that zBMI was significantly associated with the shape of the left amygdala (ß = -1.1, p < 0.021, 95% CI = -2.02, -0.16), volume of the right and left pallidum (ß = 49.66, p < 0.010, 95% CI = 11.74, 87.58; ß = 47.87, p < 0.017, 95% CI = 8.48, 87.25), and cortical thickness of the lateral and right medial orbitofrontal cortex (ß = -0.06, p < 0.001, 95% CI = -0.09, -0.04; ß = -0.05, p = 0.004, 95% CI = -0.08, -0.02). Sensitivity to food reward significantly predicted volume of the right nucleus accumbens (ß = 0.66, p = 0.047, 95% CI = 0.01, 1). Contrast mapping for surface shape of the amygdala revealed significant outward deformation of the posterior lateral left amygdala and an inward deformation of the basolateral left amygdala in the group with overweight/obesity. CONCLUSIONS: Integrity of the left amygdala and orbitofrontal cortex varies as a function of body mass, with greater localized amygdalar volume loss, pallidum volume, and increased cortical thinning of the orbitofrontal cortex occurring as weight increases. Thus, overweight/obesity may be associated with surface-based abnormalities in brain structures associated with processing of reward value related to food. Overall, findings highlight the importance of understanding changes in reward-related brain regions and how they pertain to variability in body mass in adolescent girls.
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Adelgazamiento de la Corteza Cerebral , Sobrepeso , Adolescente , Encéfalo , Femenino , Humanos , Imagen por Resonancia Magnética , Obesidad , RecompensaRESUMEN
INTRODUCTION: Primary progressive aphasia (PPA) displays variable progression trajectories that require further elucidation. METHODS: Longitudinal quantitation of atrophy and language over 12 months was completed for PPA patients with and without positive amyloid PET (PPAAß+ and PPAAß-), an imaging biomarker of underlying Alzheimer's disease. RESULTS: Over 12 months, both PPA groups showed significantly greater cortical atrophy rates in the left versus right hemisphere, with a more widespread pattern in PPAAß+. The PPAAß+ group also showed greater decline in performance on most language tasks. There was no obligatory relationship between the logopenic PPA variant and amyloid status. Effect sizes from quantitative MRI data were more robust than neuropsychological metrics. DISCUSSION: Preferential language network neurodegeneration is present in PPA irrespective of amyloid status. Clinical and anatomical progression appears to differ for PPA due to Alzheimer's disease versus non-Alzheimer's disease neuropathology, a distinction that may help to inform prognosis and the design of intervention trials.
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Enfermedad de Alzheimer/patología , Afasia Progresiva Primaria , Atrofia/patología , Encéfalo/patología , Enfermedad de Alzheimer/diagnóstico por imagen , Péptidos beta-Amiloides/genética , Afasia Progresiva Primaria/diagnóstico por imagen , Afasia Progresiva Primaria/patología , Biomarcadores , Progresión de la Enfermedad , Femenino , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Tomografía de Emisión de PositronesRESUMEN
SchizConnect (www.schizconnect.org) is built to address the issues of multiple data repositories in schizophrenia neuroimaging studies. It includes a level of mediation--translating across data sources--so that the user can place one query, e.g. for diffusion images from male individuals with schizophrenia, and find out from across participating data sources how many datasets there are, as well as downloading the imaging and related data. The current version handles the Data Usage Agreements across different studies, as well as interpreting database-specific terminologies into a common framework. New data repositories can also be mediated to bring immediate access to existing datasets. Compared with centralized, upload data sharing models, SchizConnect is a unique, virtual database with a focus on schizophrenia and related disorders that can mediate live data as information is being updated at each data source. It is our hope that SchizConnect can facilitate testing new hypotheses through aggregated datasets, promoting discovery related to the mechanisms underlying schizophrenic dysfunction.
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Bases de Datos Factuales , Conjuntos de Datos como Asunto , Difusión de la Información/métodos , Neuroimagen , Esquizofrenia/patología , Adolescente , Adulto , Anciano , Niño , Sistemas de Administración de Bases de Datos , Femenino , Humanos , Internet , Masculino , Persona de Mediana Edad , Terminología como Asunto , Interfaz Usuario-Computador , Adulto JovenRESUMEN
Cannabis use has been associated with episodic memory (EM) impairments and abnormal hippocampus morphology among both healthy individuals and schizophrenia subjects. Considering the hippocampus' role in EM, research is needed to evaluate the relationship between cannabis-related hippocampal morphology and EM among healthy and clinical groups. We examined differences in hippocampus morphology between control and schizophrenia subjects with and without a past (not current) cannabis use disorder (CUD). Subjects group-matched on demographics included 44 healthy controls (CON), 10 subjects with a CUD history (CON-CUD), 28 schizophrenia subjects with no history of substance use disorders (SCZ), and 15 schizophrenia subjects with a CUD history (SCZ-CUD). Large-deformation, high-dimensional brain mapping with MRI produced surface-based representations of the hippocampus that were compared across all four groups and correlated with EM and CUD history. Surface maps of the hippocampus were generated to visualize morphological differences. CON-CUD and SCZ-CUD were characterized by distinct cannabis-related hippocampal shape differences and parametric deficits in EM performance. Shape differences observed in CON-CUD were associated with poorer EM performance, while shape differences observed in SCZ-CUD were associated with a longer duration of CUD and shorter duration of CUD remission. A past history of CUD may be associated with notable differences in hippocampal morphology and EM impairments among adults with and without schizophrenia. Although the results may be compatible with a causal hypothesis, we must consider that the observed cannabis-related shape differences in the hippocampus could also be explained as biomarkers of a neurobiological susceptibility to poor memory or the effects of cannabis.
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Hipocampo/patología , Fumar Marihuana/fisiopatología , Trastornos de la Memoria/etiología , Trastornos de la Memoria/patología , Memoria Episódica , Esquizofrenia/patología , Adolescente , Adulto , Análisis de Varianza , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Escalas de Valoración Psiquiátrica , Adulto JovenRESUMEN
Background: Schizophrenia is associated with an increased risk of aggressive behaviour, which may partly be explained by illness-related changes in brain structure. However, previous studies have been limited by group-level analyses, small and selective samples of inpatients and long time lags between exposure and outcome. Methods: This cross-sectional study pooled data from 20 sites participating in the international ENIGMA-Schizophrenia Working Group. Sites acquired T1-weighted and diffusion-weighted magnetic resonance imaging scans in a total of 2095 patients with schizophrenia and 2861 healthy controls. Measures of grey matter volume and white matter microstructural integrity were extracted from the scans using harmonised protocols. For each measure, normative modelling was used to calculate how much patients deviated (in z-scores) from healthy controls at the individual level. Ordinal regression models were used to estimate the associations of these deviations with concurrent aggressive behaviour (as odds ratios [ORs] with 99% confidence intervals [CIs]). Mediation analyses were performed for positive symptoms (i.e., delusions, hallucinations and disorganised thinking), impulse control and illness insight. Aggression and potential mediators were assessed with the Positive and Negative Syndrome Scale, Scale for the Assessment of Positive Symptoms or Brief Psychiatric Rating Scale. Results: Aggressive behaviour was significantly associated with reductions in total cortical volume (OR [99% CI] = 0.88 [0.78, 0.98], p = .003) and global white matter integrity (OR [99% CI] = 0.72 [0.59, 0.88], p = 3.50 × 10-5) and additional reductions in dorsolateral prefrontal cortex volume (OR [99% CI] = 0.85 [0.74, 0.97], p =.002), inferior parietal lobule volume (OR [99% CI] = 0.76 [0.66, 0.87], p = 2.20 × 10-7) and internal capsule integrity (OR [99% CI] = 0.76 [0.63, 0.92], p = 2.90 × 10-4). Except for inferior parietal lobule volume, these associations were largely mediated by increased severity of positive symptoms and reduced impulse control. Conclusions: This study provides evidence that the co-occurrence of positive symptoms, poor impulse control and aggressive behaviour in schizophrenia has a neurobiological basis, which may inform the development of therapeutic interventions.
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A decline in intellectual functioning (intelligence quotient [IQ]) is often observed following more severe forms of traumatic brain injury (TBI) and is a useful index for long-term outcome. Identifying brain correlates of IQ can serve to inform developmental trajectories of behavior in this population. Using magnetic resonance imaging (MRI), we examined the relationship between intellectual abilities and patterns of cortical thickness in children with a history of TBI or with orthopedic injury (OI) in the chronic phase of injury recovery. Participants were 47 children with OI and 58 children with TBI, with TBI severity ranging from complicated-mild to severe. Ages ranged from 8 to 14 years old, with an average age of 10.47 years, and an injury-to-test range of â¼1-5 years. The groups did not differ in age or sex. The intellectual ability estimate (full-scale [FS]IQ-2) was derived from a two-form (Vocabulary and Matrix Reasoning subtests) Wechsler Abbreviated Scale of Intelligence (WASI). MRI data were processed using the FreeSurfer toolkit and harmonized across data collection sites using neuroComBat procedures, while holding demographic features (i.e., sex, socioeconomic status [SES]), TBI status, and FSIQ-2 constant. Separate general linear models per group (TBI and OI) and a single interaction model with all participants were conducted with all significant results withstanding correction for multiple comparisons via permutation testing. Intellectual ability was higher (p < 0.001) in the OI group (FSIQ-2 = 110.81) than in the TBI group (FSIQ-2 = 99.81). In children with OI, bi-hemispheric regions, including the right pre-central gyrus and precuneus and bilateral inferior temporal and left occipital areas were related to IQ, such that higher IQ was associated with thicker cortex in these regions. In contrast, only cortical thickness in the right pre-central gyrus and bilateral cuneus positively related to IQ in children with TBI. Significant interaction effects were found in the bilateral temporal, parietal, and occipital lobes and left frontal regions, indicating that the relationship between IQ and cortical thickness differed between groups in these regions. Changes in cortical associations with IQ after TBI may reflect direct injury effects and/or adaptation in cortical structure and intellectual functioning, particularly in the bilateral posterior parietal and inferior temporal regions. This suggests that the substrates of intellectual ability are particularly susceptible to acquired injury in the integrative association cortex. Longitudinal work is needed to account for normal developmental changes and to investigate how cortical thickness and intellectual functioning and their association change over time following TBI. Improved understanding of how TBI-related cortical thickness alterations relate to cognitive outcome could lead to improved predictions of outcome following brain injury.
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Lesiones Traumáticas del Encéfalo , Lesiones Encefálicas , Humanos , Niño , Lactante , Preescolar , Adolescente , Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/diagnóstico por imagen , Lesiones Traumáticas del Encéfalo/patología , Encéfalo/patología , Cognición , Lesiones Encefálicas/complicaciones , Imagen por Resonancia Magnética/métodosRESUMEN
Primary progressive aphasia (PPA) is a clinical dementia syndrome characterized by progressive decline in language function but relative sparing of other cognitive domains. There are three recognized PPA variants: agrammatic, semantic, and logopenic. Although each PPA subtype is characterized by the nature of the principal deficit, individual patients frequently display subtle impairments in additional language domains. The present study investigated the distribution of atrophy related to performance in specific language domains (i.e., grammatical processing, semantic processing, fluency, and sentence repetition) across PPA variants to better understand the anatomical substrates of language. Results showed regionally specific relationships, primarily in the left hemisphere, between atrophy and impairments in language performance. Most notable was the neuroanatomical distinction between fluency and grammatical processing. Poor fluency was associated with regions dorsal to the traditional boundaries of Broca's area in the inferior frontal sulcus and the posterior middle frontal gyrus, whereas grammatical processing was associated with more widespread atrophy, including the inferior frontal gyrus and supramarginal gyrus. Repetition performance was correlated with atrophy in the posterior superior temporal gyrus. The correlation of atrophy with semantic processing impairment was localized to the anterior temporal poles. Atrophy patterns were more closely correlated with domain-specific performance than with subtype. These results show that PPA reflects a selective disruption of the language network as a whole, with no rigid boundaries between subtypes. Further, these atrophy patterns reveal anatomical correlates of language that could not have been surmised in patients with aphasia resulting from cerebrovascular lesions.
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Estimulación Acústica/métodos , Afasia Progresiva Primaria/patología , Corteza Auditiva/patología , Anciano , Anciano de 80 o más Años , Afasia Progresiva Primaria/psicología , Atrofia , Corteza Auditiva/fisiología , Femenino , Humanos , Trastornos del Lenguaje/patología , Trastornos del Lenguaje/psicología , Masculino , Persona de Mediana Edad , Habla/fisiologíaRESUMEN
Children of Alzheimer's disease (AD) patients are at heightened risk of developing AD due to genetic influences, including the apolipoprotein E4 (ApoE4) allele. In this study, we assessed the earliest cortical changes associated with AD in 71 cognitively healthy, adult children of AD patients (AD offspring) as compared with 69 with no family history of AD (non-AD offspring). Cortical thickness measures were obtained using FreeSurfer from 1.5T magnetic resonance (MR) scans. ApoE genotyping was obtained. Primary analyses examined family history and ApoeE4 effects on cortical thickness. Secondary analyses examined age effects within groups. All comparisons were adjusted using False Discovery Rate at a significance threshold of p<0.05. There were no statistically significant differences between family history and ApoE4 groups. Within AD offspring, increasing age was related to reduced cortical thickness (atrophy) over large areas of the precuneus, superior frontal and superior temporal gyri, starting at around age 60. Further, these patterns existed within female and maternal AD offspring, but were absent in male and paternal AD offspring. Within non-AD offspring, negative correlations existed over small regions of the superior temporal, insula and lingual cortices. These results suggest that as AD offspring age, cortical atrophy is more prominent, particularly if the parent with AD is mother or if the AD offspring is female.
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Envejecimiento/fisiología , Enfermedad de Alzheimer/patología , Corteza Cerebral/patología , Anciano , Alelos , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/psicología , Apolipoproteína E4/genética , Familia , Femenino , Lateralidad Funcional/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Lineales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Padres , RiesgoRESUMEN
First-episode psychosis (FEP) is a particularly high-risk period for suicide. Literature suggests poor cognitive functioning may serve as a protective factor, while investigations of clinical insight reveal a complex relationship with suicide outcomes. This study examined the mediating role of cognition and clinical insight in the relationships between positive and negative symptoms, depression, and subsequent suicide ideation among individuals in FEP. Data were obtained from the Recovery After an Initial Schizophrenia Episode project. Participants (n = 404) included adolescents and adults in FEP between the ages of 15 and 40. Measurement utilized the Calgary Depression Rating Scale, Positive and Negative Syndrome Scale, and Brief Assessment of Cognition in Schizophrenia. Structural equation modeling was used to examine the mediation model. The likelihood of experiencing suicide ideation was significantly decreased when working memory was stronger (b = -0.034, SE = 0.02, OR = 0.967, p < .05), and significantly increased when clinical insight was stronger (b = 0.191, SE = 0.08, OR = 1.21, p < .01), positive symptoms were greater (b = 0.422, SE = 0.20, OR = 1.52, p < .05) and depressive symptoms were greater (b = 0.545, SE = 0.15, OR = 1.70, p < .001). Clinical insight and working memory functioned as mediators in the relationships between depression, positive symptoms, negative symptoms, and suicide ideation. Findings suggest it is essential that clinicians have awareness of insight being a risk factor for suicide ideation and balance therapeutic efforts to strengthen clinical insight and cognition in psychosocial treatments with suicide risk assessment and prevention methods.
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Trastornos Psicóticos , Esquizofrenia , Adolescente , Adulto , Cognición , Depresión/psicología , Humanos , Trastornos Psicóticos/psicología , Esquizofrenia/diagnóstico , Ideación Suicida , Adulto JovenRESUMEN
Early-onset schizophrenia (EOS) shares many biological and clinical features with adult-onset schizophrenia (AOS), but may represent a unique subgroup with greater susceptibility for disease onset and worsened symptomatology and progression, which could potentially derive from exaggerated neurodevelopmental abnormalities. Neurobiological explanations of schizophrenia have emphasized the involvement of deep-brain structures, particularly alterations of the thalamus, which have been linked to core features of the disorder. The aim of this study was to compare thalamic shape abnormalities between EOS and AOS subjects and determine whether unique behavioral profiles related to these differences. It was hypothesized abnormal thalamic shape would be observed in anterior, mediodorsal and pulvinar regions in both schizophrenia groups relative to control subjects, but exacerbated in EOS. Magnetic resonance T1-weighted images were collected from adult individuals with EOS (n = 28), AOS (n = 33), and healthy control subjects (n = 60), as well as collection of clinical and cognitive measures. Large deformation high-dimensional brain mapping was used to obtain three-dimensional surfaces of the thalamus. General linear models were used to compare groups on surface shape features, and Pearson correlations were used to examine relationships between thalamic shape and behavioral measures. Results revealed both EOS and AOS groups demonstrated significant abnormal shape of anterior, lateral and pulvinar thalamic regions relative to CON (all p < 0.007). Relative to AOS, EOS exhibited exacerbated abnormalities in posterior lateral, mediodorsal and lateral geniculate thalamic regions (p = 0.003). Thalamic abnormalities related to worse episodic memory in EOS (p = 0.03) and worse working memory (p = 0.047) and executive functioning (p = 0003) in AOS. Overall, findings suggest thalamic abnormalities are a prominent feature in both early- and late-onset schizophrenia, but exaggerated in EOS and have different brain-behavior profiles for each. The persistence of these abnormalities in adult EOS patients suggests they may represent markers of disrupted neurodevelopment that uniquely relate to the clinical and cognitive aspects of the illness.
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We have previously shown that schizophrenia (SCZ) participants with high community functioning demonstrate better verbal working memory (vWM) performance relative to those with low community functioning. In the present study, we investigated whether neuroanatomical differences in regions supporting vWM also exist between schizophrenia groups that vary on community functioning. Utilizing magnetic resonance imaging, shape features of deep-brain nuclei known to be involved in vWM were calculated in samples of high functioning (HF-SCZ, n = 23) and low functioning schizophrenia participants (LF-SCZ, n = 18), as well as in a group of healthy control participants (CON, n = 45). Large deformation diffeomorphic metric mapping was employed to characterize surface anatomy of the caudate nucleus, globus pallidus, hippocampus, and thalamus. Statistical analyses involved linear mixed-effects models and vertex-wise contrast mapping to assess between-group differences in structural shape features, and Pearson correlations to evaluate relationships between shape metrics and vWM performance. We found significant between-group main effects in deep-brain surface anatomy across all structures. Post-hoc comparisons revealed HF-SCZ and LF-SCZ groups significantly differed on both caudate and hippocampal shape, however, significant correlations with vWM were only observed in hippocampal shape for both SCZ groups. Specifically, more abnormal hippocampal deformation was associated with lower vWM suggesting hippocampal shape is both a neural substrate for vWM deficits and a potential biomarker to predict or monitor the efficacy of cognitive rehabilitation. These findings add to a growing body of literature related to functional outcomes in schizophrenia by demonstrating unique shape patterns across the spectrum of community functioning in SCZ.
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Childhood traumatic brain injury (TBI) is one of the most common causes of acquired disability and has significant implications for executive functions (EF), such as impaired attention, planning, and initiation that are predictive of everyday functioning. Evidence has suggested attentional features of executive functioning require behavioral flexibility that is dependent on frontostriatial circuitry. The purpose of this study was to evaluate surface-based deformation of a specific frontostriatial circuit in pediatric TBI and its role in EF. Regions of interest included: the dorsolateral prefrontal cortex (DLPFC), caudate nucleus, globus pallidus, and the mediodorsal nucleus of the thalamus (MD). T1-weighted magnetic resonance images were obtained in a sample of children ages 8-13 with complicated mild, moderate, or severe TBI (n = 32) and a group of comparison children with orthopedic injury (OI; n = 30). Brain regions were characterized using high-dimensional surface-based brain mapping procedures. Aspects of EF were assessed using select subtests from the Test of Everyday Attention for Children (TEA-Ch). General linear models tested group and hemisphere differences in DLPFC cortical thickness and subcortical shape of deep-brain regions; Pearson correlations tested relationships with EF. Main effects for group were found in both cortical thickness of the DLPFC (F1,60 = 4.30, p = 0.042) and MD mean deformation (F1,60 = 6.50, p = 0.01) all with lower values in the TBI group. Statistical surface maps revealed significant inward deformation on ventral-medial aspects of the caudate in TBI relative to OI, but null results in the globus pallidus. No significant relationships between EF and any region of interest were observed. Overall, findings revealed abnormalities in multiple aspects of a frontostriatial circuit in pediatric TBI, which may reflect broader pathophysiological mechanisms. Increased consideration for the role of deep-brain structures in pediatric TBI can aid in the clinical characterization of anticipated long-term developmental effects of these individuals.
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Lesiones Traumáticas del Encéfalo , Adolescente , Atención , Lesiones Traumáticas del Encéfalo/complicaciones , Niño , Cognición , Función Ejecutiva/fisiología , Humanos , Pruebas NeuropsicológicasRESUMEN
There is growing evidence that schizophrenia and schizoaffective disorder represent closely related syndromes that vary in severity along a neurobiological continuum. In the present study, volume and shape of the basal ganglia was examined in people with schizophrenia and schizoaffective disorder relative to healthy controls and hypothesized that unique neuroanatomical differences would be observed in each patient group. Magnetic resonance 1.5T images were obtained from schizophrenia (n = 47), schizoaffective disorder (n = 15), and from healthy control (n = 42) participants, matched for age, gender, parental socioeconomic status, and race. The caudate, putamen, and globus pallidus were characterized using high-dimensional brain mapping procedures (Csernansky et al., 2004b). Results revealed significant shape deformations between schizophrenia and schizoaffective disorder that also differed from control subjects. Relative to schizophrenia, schizoaffective subjects showed exaggerated inward deformations indicative of localized volume loss in subregions of the caudate, putamen, and globus pallidus (all p < 0.001). These shape features correlated with mental flexibility and negative symptoms in schizophrenia (all p < 0.05), but not schizoaffective disorder. To the extent that differences in important basal ganglia substructures reflect biological heterogeneity among these two psychotic illnesses, this data could prove useful in improving diagnostic precision, as well as informing the affective component of mental illness.
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Trastornos Psicóticos , Esquizofrenia , Ganglios Basales/diagnóstico por imagen , Mapeo Encefálico , Humanos , Imagen por Resonancia Magnética , Trastornos Psicóticos/diagnóstico por imagen , Trastornos Psicóticos/patología , Esquizofrenia/patologíaRESUMEN
BACKGROUND: Suicide is a leading cause of death for individuals with psychosis. Although factors influencing suicide risk have been studied in schizophrenia, far less is known about factors that protect against or trigger increased risk during early-stage and first episode of psychosis. This study examined whether depression, psychotic symptoms, clinical insight, and cognition were associated with suicide ideation among individuals with first-episode psychosis. METHODS: Data were obtained from the Recovery After an Initial Schizophrenia Episode (RAISE) project. Participants (n = 404) included adults between ages 15 and 40 in a first episode of psychosis. Measurement included the Positive and Negative Syndrome Scale, Brief Assessment of Cognition in Schizophrenia, and Calgary Depression Scale for Schizophrenia. A logistic regression model evaluated clinical and cognitive variables as predictors of suicidal ideation. RESULTS: Greater positive symptoms (OR = 1.085, p < .01) and depression (OR = 1.258, p < .001) were associated with increased likelihood of experiencing suicidal ideation during the RAISE project. Meanwhile, stronger working memory (OR = 0.922, p < .05) and impaired clinical insight (OR = 0.734, p < .05) were associated with a decreased likelihood of experiencing suicidal ideation. CONCLUSION: The likelihood of experiencing suicidal ideation was significantly increased when positive and depressive symptoms were present, and significantly decreased when clinical insight was poorer and working memory stronger. These findings have important implications for the role of cognition and insight in risk for suicide ideation in early-stage psychosis, which may aid in improving the prediction of suicide behaviors and inform clinical decision-making over the course of the illness.
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Trastornos Psicóticos , Esquizofrenia , Adolescente , Adulto , Cognición , Depresión/epidemiología , Humanos , Trastornos Psicóticos/complicaciones , Trastornos Psicóticos/epidemiología , Factores de Riesgo , Esquizofrenia/complicaciones , Esquizofrenia/epidemiología , Ideación Suicida , Adulto JovenRESUMEN
Objective: Deficits in cognitive empathy are well-documented in individuals with schizophrenia and are related to reduced community functioning. The temporoparietal junction (TPJ) is closely linked to cognitive empathy. We compared the relationship between baseline cognitive empathy and changes in TPJ thickness over 24 months between individuals with schizophrenia and healthy controls. Methods: Individuals with schizophrenia (n = 29) and healthy controls (n = 26) completed a cognitive empathy task and underwent structural neuroimaging at baseline and approximately 24 months later. Symmetrized percent change scores were calculated for right and left TPJ, as well as whole-brain volume, and compared between groups. Task accuracy was examined as a predictor of percent change in TPJ thickness and whole-brain volume in each group. Results: Individuals with schizophrenia demonstrated poorer accuracy on the cognitive empathy task (p < 0.001) and thinner TPJ cortex relative to controls at both time points (p = 0.01). In schizophrenia, greater task accuracy was uniquely related to less thinning of the TPJ over time (p = 0.02); task accuracy did not explain changes in left TPJ or whole-brain volume. Among controls, task accuracy did not explain changes in right or left TPJ, or whole-brain volume. Conclusions: Our findings suggest that greater cognitive empathy may explain sustained integrity of the right TPJ in individuals with schizophrenia, suggesting a contributory substrate for the long-term maintenance of this process in psychosis. Cognitive empathy was not related to changes in whole-brain volume, demonstrating the unique role of the TPJ in cognitive empathy.
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The semantic variant of primary progressive aphasia (PPA) is characterized by the combination of word comprehension deficits, fluent aphasia and a particularly severe anomia. In this study, two novel tasks were used to explore the factors contributing to the anomia. The single most common factor was a blurring of distinctions among members of a semantic category, leading to errors of overgeneralization in word-object matching tasks as well as in word definitions and object descriptions. This factor was more pronounced for natural kinds than artifacts. In patients with the more severe anomias, conceptual maps were more extensively disrupted so that inter-category distinctions were as impaired as intra-category distinctions. Many objects that could not be named aloud could be matched to the correct word in patients with mild but not severe anomia, reflecting a gradual intensification of the semantic factor as the naming disorder becomes more severe. Accurate object descriptions were more frequent than accurate word definitions and all patients experienced prominent word comprehension deficits that interfered with everyday activities but no consequential impairment of object usage or face recognition. Magnetic resonance imaging revealed three characteristics: greater atrophy of the left hemisphere; atrophy of anterior components of the perisylvian language network in the superior and middle temporal gyri; and atrophy of anterior components of the face and object recognition network in the inferior and medial temporal lobes. The left sided asymmetry and perisylvian extension of the atrophy explains the more profound impairment of word than object usage and provides the anatomical basis for distinguishing the semantic variant of primary progressive aphasia from the partially overlapping group of patients that fulfil the widely accepted diagnostic criteria for semantic dementia.
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Anomia/etiología , Afasia Progresiva Primaria/complicaciones , Semántica , Anciano , Anomia/patología , Anomia/fisiopatología , Afasia Progresiva Primaria/patología , Afasia Progresiva Primaria/fisiopatología , Atrofia/patología , Femenino , Lóbulo Frontal/patología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Tiempo de Reacción , Lóbulo Temporal/patologíaRESUMEN
OBJECTIVES: To determine the prevalence of cognitive impairment no dementia (CIND) among a diverse, community-based population, and establish associations between CIND and health literacy, chronic disease self-management and functional health status. METHODS: 863 primary care adults without dementia aged 55-74. Adjusted logistic and linear regressions were used to assess associations between CIND (None, Mild, Moderate/Severe) and outcomes. RESULTS: 36 % participants exhibited CIND. It was strongly associated with limited health literacy (Newest Vital Signs: Mild [OR 3.25; 95 % CI 1.93, 5.49], Moderate/Severe [OR 6.45; 95 % CI 3.16, 13.2]; Test of Functional Health Literacy in Adults: Mild [OR 3.46; 95 % CI 2.08, 5.75], Moderate/Severe [OR 8.82; 95 % CI 4.87, 16.0]; all p's < 0.001) and poor chronic disease self-management (Mild [B = -11.2; 95 % CI -13.5, -8.90], Moderate/Severe CI [B = -21.0; 95 % CI -23.6, -18.4]; both p's < 0.001). Associations between CIND and functional health status were non-significant. CONCLUSIONS: CIND was prevalent in this cohort, and strongly associated with requisite skills for managing everyday health needs. PRACTICE IMPLICATIONS: Attention to subtle declines in chronic disease self-care may assist with CIND identification and care management within this population. When CIND is observed, clinicians should also expect and address difficulties with self-management.
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Actividades Cotidianas , Disfunción Cognitiva/epidemiología , Alfabetización en Salud , Automanejo , Anciano , Enfermedad Crónica , Estudios Transversales , Femenino , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estados Unidos/epidemiologíaRESUMEN
OBJECTIVE: The purpose of the current review paper is to identify and describe challenges to work-life integration in neuropsychology, and from this review extrapolate an initial set of recommendations and present a set of scenarios in which the recommendations might apply in the hopes of improving quality of life for current and prospective neuropsychologists. Specific areas of focus include diversity, early and mid-career transitions, and potential barriers to advancement in specific practice settings. METHOD: A broad review was conducted of extant literature on work-life integration. There is scant scientific literature in this area that is specific to neuropsychologists, or even psychology as a whole. Subsequently, the majority of this review was collected from more developed literatures in business and medical fields. The authors then provided recommendations based on experiences in their respective careers. Attempts were made to promote generalizability of recommendations for neuropsychologists in different settings. RESULTS: Evidence supports a potentially adverse impact on quality of life and overall life satisfaction when work and personal lives conflict. CONCLUSION: This manuscript identifies some of the potential risks when work and life responsibilities are not well integrated. It is anticipated this will serve as a catalyst for future studies on work-life integration in the field of neuropsychology, specifically.
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Neuropsicología/organización & administración , Adulto , Familia , Femenino , Identidad de Género , Humanos , Satisfacción en el Trabajo , Masculino , Persona de Mediana Edad , Satisfacción Personal , Psicología , Calidad de VidaRESUMEN
Few studies have compared performance on neurocognitive measures between violent and nonviolent schizophrenia samples. A better understanding of neurocognitive dysfunction in violent individuals with schizophrenia could increase the efficacy of violence reduction strategies and aid in risk assessment and adjudication processes. This study aimed to compare neuropsychological performance between 25 homicide offenders with schizophrenia and 25 nonviolent schizophrenia controls. The groups were matched for age, race, sex, and handedness. Independent t-tests and Mann-Whitney U-tests were used to compare the schizophrenia groups' performance on measures of cognition, including composite scores assessing domain level functioning and individual neuropsychological tests. Results indicated the violent schizophrenia group performed worse on measures of memory and executive functioning, and the Intellectual Functioning composite score, when compared to the nonviolent schizophrenia sample. These findings replicate previous research documenting neuropsychological deficits specific to violent individuals with schizophrenia and support research implicating fronto-limbic dysfunction among violent offenders with schizophrenia.