Strong evidence implicates prefrontal cortex (PFC) as a major source of functional impairment in severe mental illness such as schizophrenia. Numerous schizophrenia studies report deficits in PFC structure, activation, and functional connectivity in patients with chronic illness, suggesting that deficient PFC functional connectivity occurs in this disorder. However, the PFC functional connectivity patterns during illness onset and its longitudinal progression remain uncharacterized. Emerging evidence suggests that early-course schizophrenia involves increased PFC glutamate, which might elevate PFC functional connectivity. To test this hypothesis, we examined 129 non-medicated, human subjects diagnosed with early-course schizophrenia and 106 matched healthy human subjects using both whole-brain data-driven and hypothesis-driven PFC analyses of resting-state fMRI. We identified increased PFC connectivity in earlycourse patients, predictive of symptoms and diagnostic classification, but less evidence for "hypoconnectivity." At the whole-brain level, we observed "hyperconnectivity" around areas centered on the default system, with modest overlap with PFC-specific effects. The PFC hyperconnectivity normalized for a subset of the sample followed longitudinally (n ϭ 25), which also predicted immediate symptom improvement. Biologically informed computational modeling implicates altered overall connection strength in schizophrenia. The initial hyperconnectivity, which may decrease longitudinally, could have prognostic and therapeutic implications.
Although previous studies have reported deficits in the gray matter volume of schizophrenic patients, it remains unclear whether these deficits occur at the onset of the disease, before treatment, and whether they are progressive over the duration of untreated disease. Furthermore, the gray matter volume represents the combinations of cortical thickness and surface area; these features are believed to be influenced by different genetic factors. However, cortical thickness and surface area in antipsychotic-naive first-episode schizophrenic patients have seldom been investigated. Here, the cortical thicknesses and surface areas of 128 antipsychotic-naive first-episode schizophrenic patients were compared with 128 healthy controls. The patients exhibited significantly lower cortical thickness, primarily in the bilateral prefrontal and parietal cortex, and increased thickness in the bilateral anterior temporal lobes, left medial orbitofrontal cortex, and left cuneus. Furthermore, decreased cortical thickness was related to positive schizophrenia symptoms but not to the severity of negative symptoms and the untreated disease duration. No significant difference of surface area was observed between the 2 groups. Thus, without the confounding factors of medication and illness progression, this study provides further evidence to support anatomical deficits in the prefrontal and parietal cortex early in course of the illness. The increased thicknesses of the bilateral anterior temporal lobes may represent a compensatory factor or may be an early-course neuronal pathology caused by preapoptotic osmotic changes or hypertrophy. Furthermore, these anatomical deficits are crucial to the pathogenesis of positive symptoms and relatively stable instead of progressing during the early stages of the disease.
IMPORTANCE Accumulating evidence supports the hypothesis that cerebral white matter abnormalities are involved in the pathophysiology of schizophrenia; however, findings from in vivo neuroimaging studies have been inconsistent. Besides confounding factors, including age, illness duration, and medication effects, an additional cause for the inconsistent results may be heterogeneity in the nature of white matter alterations associated with the disorder.OBJECTIVE To investigate whether different patterns of white matter abnormalities exist in a large cohort of medication-naive patients with first-episode schizophrenia and the relationship between such patterns and clinical parameters. DESIGN, SETTING, AND PARTICIPANTSA cross-sectional diffusion tensor imaging study of 113 medication-naive patients with first-episode schizophrenia and 110 demographically matched healthy control individuals. The study was conducted in the mental health center of West
Both social support from family members and cognitive function appear to be key factors associated with quality of life among the very old in China. Further research is needed among very old populations to confirm the importance of these variables and to examine potential cross-cultural differences.
Purpose To determine whether the brain functional abnormalities of drug-naive first-episode schizophrenia are reduced after 1 year of undergoing antipsychotic treatment and whether pretreatment resting-state functional magnetic resonance (MR) imaging parameters are associated with longitudinal changes in clinical symptoms. Materials and Methods This prospective study was approved by the local ethical committee, and written informed consent was obtained from all participants. Twenty antipsychotic-naive first-episode patients with schizophrenia and 16 healthy individuals were recruited and underwent resting-state functional MR imaging at baseline and again at 1-year follow-up, by which time significant clinical improvement was seen. The amplitude of low-frequency fluctuation (ALFF) and seed-based functional connectivity (FC) were analyzed with analysis of covariance. Results The amount of ALFF in the right inferior parietal lobule (IPL) and orbitofrontal cortex (OFC) and the amount of FC between the bilateral IPLs significantly increased over the follow-up period, and the amount of ALFF in the right occipital gyrus was reduced (P < .050, AlphaSim corrected [ http://afni.nimh.nih.gov/pub/dist/doc/manual/AlphaSim.pdf ]), returning toward normal levels. Furthermore, the degree of alteration in ALFF values in the right OFC (P = .037) and occipital gyrus (P = .002) at baseline was significantly correlated with the magnitude of the normalization in those regions at 1-year follow-up. In contrast, abnormalities of ALFF in the bilateral thalamus, ventral medial prefrontal cortex, precuneus, and right amygdala and of FC between the right OFC and the dorsal medial prefrontal cortex at baseline did not improve in patients at 1-year follow-up. Conclusion These findings show that some, but not all, neurophysiologic alterations that occur during the acute phase of schizophrenia are normalized in the context of clinical improvement and suggest therapeutic implications for exploration of which alterations in regional and network-level brain function evolve over time in patients with schizophrenia and which reflect persistent pathologic traits. Online supplemental material is available for this article.
Some neuropsychological abilities, particularly those affecting memory, attention and executive function, are impaired amongst both schizophrenic patients and their unaffected relatives, implying that these deficits are at least partly genetic in origin. However neuropsychological performance can be altered by medication, and has rarely been examined in first onset, drug naive patients. The objective of this study was to determine whether selected neurocognitive abilities are impaired in first-onset schizophrenic patients and their relatives compared to controls. We examined attention and speed of information processing, memory and learning, verbal function, visuoconstructive abilities and executive function in 207 first-episode schizophrenic patients (163 of whom were drug naïve), 322 of their first-degree relatives and 133 unrelated normal controls. The data were subjected to multilevel modeling to compare neurocognitive performance between schizophrenic probands, relatives and controls while taking into account potential correlations among members of the same family; age, gender, and years of education were included as covariates. Of the three groups, schizophrenic patients performed poorest at all neuropsychological tests, suggestive of a broad range of neurocognitive deficits. Their first-degree relatives showed a narrower pattern of poor performance at Digit Symbol, Digit Span, Trail Making, Verbal Fluency test, Tower of Hanoi, and WCST-M tests. Our findings show that selected neurocognitive deficits especially attention and executive function are impaired in the families of schizophrenic patients. These patterns of neurocognitive deficits may represent "endophenotypes" denoting varying degrees of vulnerability to schizophrenia and may be of value in future molecular genetic studies.
We conducted a national survey among medical students in China to estimate the prevalence of depressive symptoms and explore associated risk factors based on an established questionnaire composed of demographic information, life events in the past four weeks before survey, and the validated Chinese version of the 21-item Beck's Depression Inventory (BDI). The mean age of enrolled 9010 students was 20.7 (standard deviation: 1.6) years. BDI scores indicated that 19.9% had depressive symptoms based on the cut-off score of 14. Socioeconomic factors and student characteristics such as male sex, low monthly income per capita, father's poor education background, and higher year of study were associated with higher prevalence of depressive symptoms among medical students. Students who studied in comprehensive universities were more likely to have depressive symptoms compared with those from medical universities. Habitual smoking and alcohol drinking, sleep deprivation, and hospitalization or medication for one week or more in the last four weeks also predisposed students to higher risk of depressive symptoms. Our results indicate that depressive symptoms are becoming a highly prevalent health problem among Chinese medical students. Primary and secondary prevention should be prioritized to tackle this issue based on potential risk factors.
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