Institute of Psychology,Chinese Academy Of Sciences
Not a member yet
6627 research outputs found
Sort by
Bipolar disorder and schizophrenia share a similar deficit in semantic inhibition: A meta-analysis based on Hayling Sentence Completion Test performance
No full textBipolar disorder (BD) is associated with deficits in executive function similar to that found in schizophrenia (SZ). However, very few studies have examined whether a specific component of executive function, namely, semantic inhibition, is differentially impaired in BD and SZ. The present study reports the results of a meta-analysis of performance on a theory-driven test of semantic inhibition, namely, the Hayling Sentence Completion Test (HSCT), in patients with BD and SZ, and to examine differential group impairments. The Comprehensive Meta-Analysis Software package was used to calculate the mean effect sizes for group differences on different measures of HSCT. A total of 13 studies were included in the meta-analysis. Effect sizes for six HSCT measures were calculated. These included: Total Latency of Task A, Total Latency of Task B, Suppression Time, Total Error of Task B, Type A Error of Task B, and Type B Error of Task B. When compared with healthy controls, medium-to-large effect sizes were observed in both groups for each HSCT measure. Interestingly, the effect sizes for BD and SZ groups were comparable. These results suggest that patients with SZ and patients with BD are impaired in both task initiation and task inhibition of executive function and these impairments are similar in magnitude for both disorders. (C) 2013 Elsevier Inc. All rights reserved
Chinese dyslexics show neural differences in morphological processing
No full textPrevious behavioral studies have suggested that morphological awareness is impaired in Chinese children with reading disability (RD), but how this is reflected in brain alterations is not known. Using functional magnetic resonance imaging (fMRI), the current study compared morphological processing in a RD group (11-13-years old) to an age-matched typically developing (TD) group. Participants made semantic relatedness judgments to incongruent word pairs that were either semantically related but did not share a morpheme or semantically unrelated but did share a morpheme. This was compared to conditions where semantic relatedness and morphemic information was congruent. A smaller incongruency effect was found in left dorsal posterior (BA9) and ventral anterior (BA47) inferior frontal gyrus (IFG) in the RD compared to the TD, suggesting that the RD is less sensitive to morphological information. This was a specific deficit as a phonological control task that manipulated congruency between orthography and phonology did not show group differences in the IFG. Moreover, brain activation in the IFG for the incongruency effect in the semantic task was negatively correlated with reading skill for the RD group only, suggesting that higher skill children with RD may rely on a compensatory whole-word strategy by ignoring the morphemic information. (C) 2013 Elsevier Ltd. All rights reserved
Aging-associated excess formaldehyde leads to spatial memory deficits
No full textRecent studies show that formaldehyde participates in DNA demethylation/methylation cycle. Emerging evidence identifies that neuronal activity induces global DNA demethylation and re-methylation; and DNA methylation is a critical step for memory formation. These data suggest that endogenous formaldehyde may intrinsically link learning-responsive DNA methylation status and memory formation. Here, we report that during spatial memory formation process, spatial training induces an initial global DNA demethylation and subsequent re-methylation associated with hippocampal formaldehyde elevation then decline to baseline level in Sprague Dawley rats. Scavenging this elevated formaldehyde by formaldehyde-degrading enzyme (FDH), or enhancing DNA demethylation by a DNA demethylating agent, both led to spatial memory deficits by blocking DNA re-methylation in rats. Furthermore, we found that the normal adult rats intrahippocampally injected with excess formaldehyde can imitate the aged-related spatial memory deficits and global DNA methylation decline. These findings indicate that aging-associated excess formaldheyde contributes to cognitive decline during aging
Cognitive, emotional and neurochemical effects of repeated maternal separation in adolescent rats
No full textAs an adverse early life experience, maternal separation (MS) induces profound neurochemical, cognitive and emotional dysfunction. Previous studies have reported that MS affected prepulse inhibition (PPI), anxiety-related behaviors, dopaminergic and serotonergic activity in adult rats, and in the present study, we investigated the effects of repeated (4 h/day) maternal separation during postnatal days 1-21 on PPI and anxiety-related behaviors in an elevated plus maze, as well as dopamine D2 receptor (DRD2) and 5-HT1A receptor expression in the medial prefrontal cortex (mPFC), nucleus accumbens (NAc) and hippocampus in adolescent rats. Our findings show that repeated MS results in reduced PPI, increased anxiety-related behaviors, decreased DRD2 protein expression in the NAc and hippocampus, and decreased 5-HT1A protein expression in the mPFC and hippocampus in adolescent rats. These data further demonstrate that MS can be used as an animal model of neuropsychiatric disease. (c) 2013 Elsevier B.V. All rights reserved
Brain-network mechanisms underlying the divergent effects of depression on spontaneous versus evoked pain in rats: A multiple single-unit study
No full textStudies have reported divergent behavioral effects of depression on spontaneous vs. stimulus-evoked pain. However, the underlying neurobiological mechanisms are still unclear. The present study used a depression model of unpredictable chronic mild stress (UCMS) and pain models for spontaneous pain (i.e., the formalin test) and acute evoked pain (i.e., noxious thermal stimulation) in rats. The activity of neurons within thalamo-cortical circuits in the lateral and medial pain pathways was recorded by a multiple-channel recording technique, and behaviors were observed simultaneously. The results confirmed our previous findings that rats exposed to UCMS tended to exhibit decreased pain sensitivity to experimental stimuli but increased behavioral responses to ongoing pain. Based on the analysis of single-unit responses, the results demonstrated that the processing of spontaneous vs. evoked pain in a depressive-like state was altered in the opposite direction (activation vs. inhibition). The ensemble encoding analysis revealed that exposure to UCMS gave rise to enhanced inter-regional functional connectivity in spontaneous pain processing, but did not influence that of evoked pain. In addition, different brain activation patterns underlying the processing of spontaneous vs. evoked pain were observed. These findings revealed that the distinct response patterns of neurons within the pain-related brain circuits, especially in the affective pain pathway, mediate the divergent effects of depression on spontaneous vs. evoked pain. This is also the first report on the electrophysiology of depression models that provides direct evidence that the effect of depression on spontaneous and evoked pain may involve different brain mechanisms. (C) 2013 Elsevier Inc. All rights reserved
Alterations of Directional Connectivity among Resting-State Networks in Alzheimer Disease
No full textBACKGROUND AND PURPOSE: AD has been documented as a kind of disconnection syndrome by functional neuroimaging studies. The primary focus of this study was to examine, with the use of resting-state fMRI, whether AD would impact connectivity among RSNs. MATERIALS AND METHODS: Fourteen patients with AD and 16 NC were recruited and scanned by using resting-state fMRI. Group independent-component analysis and the BN learning approach were used, respectively, to separate the RSNs and construct the network-to-network connectivity patterns for each group. The convergence index for the special network DMN was measured. RESULTS: Three of the 4 connections were significantly lower in AD compared with NC. Although numerically the AD group had more connections, none was statistically different from that in the NC group except for 1 increased connection from the DMN to the DAN. The convergence index for the DMN node was lower in AD than in NC. CONCLUSIONS: Connections among cognitive networks in AD were more vulnerable to impairment than sensory networks. The DMN decreased its integration function for other RSNs but may also play a role in compensating for the disrupted connections in AD
Avoidance disruptive effect of clozapine and olanzapine is potentiated by increasing the test trials: Further test of the motivational salience hypothesis
No full textAntipsychotic drugs suppress animals' ability to avoid an aversive stimulus in the conditioned avoidance response model (CAR). This behavioral effect is thought to reflect antipsychotic activity and is suggested to be mediated by a drug's action in attenuating the motivational salience of a conditioned stimulus (CS). In the present study, we tested whether atypical antipsychotic drugs clozapine and olanzapine act through this behavioral mechanism by manipulating the number of avoidance test trials. We reasoned that more CS trials in the presence of clozapine or olanzapine would afford the drug more opportunities to decrease the motivational salience of the CS, thus avoidance decline would be greater with the increase of CS trials in each test session. In two separate experiments, adult male Sprague-Dawley rats were tested under clozapine (5.0 mg/kg, sc), olanzapine (0.5 mg/kg, sc) or vehicle (sterile water) for 6 consecutive days in three CS trial conditions (i.e. 3, 10, and 40 CS trials per session). Two days later, all rats were tested under the same 40-trial session after receiving clozapine (5.0 mg/kg, sc) or olanzapine (0.5 mg/kg, sc). Results show that repeated clozapine and olanzapine treatment persistently decreased avoidance response, and this effect was potentiated by the increase of number of CS trials in the test sessions, as the clozapine-treated or olanzapine-treated rats tested under the 40-trial or 10-trial condition had significantly lower avoidance and faster decline across-sessions than those tested under the 3-trial condition. This potentiated effect was not only seen in the total avoidance percentage, but also observed in the within-session decline pattern in the last three drug test sessions and in the final 40-trial test session. These findings suggest that the clinical efficacy of a drug can be enhanced by increasing the exposure of symptoms in the presence of the drug. (c) 2012 Elsevier Inc. All rights reserved
Intrinsic Resting-State Activity Predicts Working Memory Brain Activation and Behavioral Performance
No full textAlthough resting-state brain activity has been demonstrated to correspond with task-evoked brain activation, the relationship between intrinsic and evoked brain activity has not been fully characterized. For example, it is unclear whether intrinsic activity can also predict task-evoked deactivation and whether the rest-task relationship is dependent on task load. In this study, we addressed these issues on 40 healthy control subjects using resting-state and task-driven [N-back working memory (WM) task] functional magnetic resonance imaging data collected in the same session. Using amplitude of low-frequency fluctuation (ALFF) as an index of intrinsic resting-state activity, we found that ALFF in the middle frontal gyrus and inferior/superior parietal lobules was positively correlated with WM task-evoked activation, while ALFF in the medial prefrontal cortex, posterior cingulate cortex, superior frontal gyrus, superior temporal gyrus, and fusiform gyrus was negatively correlated with WM task-evoked deactivation. Further, the relationship between the intrinsic resting-state activity and task-evoked activation in lateral/superior frontal gyri, inferior/superior parietal lobules, superior temporal gyrus, and midline regions was stronger at higher WM task loads. In addition, both resting-state activity and the task-evoked activation in the superior parietal lobule/precuneus were significantly correlated with the WM task behavioral performance, explaining similar portions of intersubject performance variance. Together, these findings suggest that intrinsic resting-state activity facilitates or is permissive of specific brain circuit engagement to perform a cognitive task, and that resting activity can predict subsequent task-evoked brain responses and behavioral performance. Hum Brain Mapp 34:3204-3215, 2013. (c) 2012 Wiley Periodicals, Inc
AN ERP STUDY OF EPISODIC RETRIEVAL IN AMNESTIC MILD COGNITIVE IMPAIRMENT AND NORMAL ELDERLY WITH MATCHED PERFORMANCE
No full textPrevalence of Inconsistent Condom Use and Associated Factors Among HIV Discordant Couples in a Rural County in China
No full textA random sample consisting of 88 sexually active people living with HIV (PLWH) and their HIV negative spouses in rural China were interviewed. Data of 68 couples (77.2 %) who gave identical responses to whether they had been using condoms consistently in the last 12 months (n = 136) were analyzed. The results showed that 27.9 % of the discordant couples used condom inconsistently in the last year. Condom non-availability was the most commonly given main reason for not using condoms. Free condoms should be made available to these low-income couples. Suicidal ideation of the PLWH and the spouse's perception on 'whether someone could contract HIV via unprotected sexual intercourse with a HIV positive person' were significantly associated with inconsistent condom use in the last year. Education program should change the cognition about the risk for HIV transmission via unprotected sex. Integrated psychological services to reduce suicidal ideation are greatly warranted
Access Repository Dashboard
Do you manage Institute of Psychology,Chinese Academy Of Sciences? Access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard!