Face and object visual working memory deficits in first-episode schizophrenia correlate with multiple neurocognitive performances

Background Working memory(WM)deficit is considered a core feature and cognitive biomarker in patients with schizophrenia.Several studies have reported prominent object WM deficits in patients with schizophrenia,suggesting that visual WM in these patients extends to non-spatial domains.However,whether non-spatial WM is similarly affected remains unclear.Aim This study primarily aimed to identify the processing of visual object WM in patients with first-episode schizophrenia.Methods The study included 36 patients with first-episode schizophrenia and 35 healthy controls.Visual object WM capacity,including face and house WM capacity,was assessed by means of delayed matching-to sample visual WM tasks,in which participants must distribute memory so that they can discriminate a target sample.We specifically examined their anhedonia experience by the Temporal Experience of Pleasure Scale and the Snaith-Hamilton Pleasure Scale.Cognitive performance was measured by the Repeatable Battery for the Assessment of Neuropsychological Status(RBANS).Results Both face and house WM capacity was significantly impaired in patients with schizophrenia.For both tasks,the performance of all the subjects was worse under the high-load condition than under the low-load condition.We found that WM capacity was highly positively correlated with the performance on RBANS total scores(r=−0.528,p=0.005),RBANS delayed memory scores(r=−0.470,p=0.013),RBANS attention scores(r=−0.584,p=0.001),RBANS language scores(r=−0.448,p=0.019),Trail-Making Test:Part A raw scores(r=0.465,p=0.015)and simple IQ total scores(r=−0.538,p=0.005),and correlated with scores of the vocabulary test(r=−0.490,p=0.011)and scores of the Block Diagram Test(r=−0.426,p=0.027)in schizophrenia.No significant correlations were observed between WM capacity and Positive and Negative Syndrome Scale symptoms.Conclusions Our research found that visual object WM capacity is dramatically impaired in patients with schizophrenia and is strongly correlated with other measures of cognition,suggesting a mechanism that is critical in explaining a portion of the broad cognitive deficits observed in schizophrenia.

视觉和听觉通道情绪知觉加工的神经机制及其异同

通过功能核磁共振(functional magnetic resonance imaging, fMRI)技术,采用情绪知觉的判断任务,探究了视觉与听觉情绪知觉加工的神经机制及其异同,进一步揭示跨通道情绪知觉加工的多重感觉皮层的脑区定位.我们选用含有恐惧、高兴或悲伤情绪的面孔和声音刺激作为实验材料,使用事件相关设计考察每种刺激诱发的激活.激活强度分析的结果显示:情绪类型主效应显著的区域主要体现在左侧额下回岛盖部,表明其作为视-听跨通道情绪知觉的皮层,是视觉和听觉情绪知觉的共同通路,且对于负性情绪,尤其是恐惧情绪刺激最为敏感.基于多体素模式分析(multi-voxel pattern analysis, MVPA)的结果发现:右侧颞上沟的激活模式能区分高兴、悲伤、恐惧的面孔,表明其对不同情绪效价的面孔知觉有重要作用;右侧梭状回面孔区的激活模式能够区分高兴和悲伤的面孔,表明其对于积极-消极情绪面孔知觉具有重要意义.本研究为深入理解人类不同通道情绪知觉的加工过程及跨通道情绪知觉的多感觉皮层提供了重要的证据和支持.

视觉工作记忆内容维持的大脑神经机制

视觉工作记忆指短暂维持不在视域内信息并进行活跃认知加工的过程,在人类高级认知活动中具有极其重要的作用.但是,目前关于人类大脑在视觉工作记忆维持阶段对多特征复杂客体(例如,面孔信息和房子信息)信息的认知加工机制还没有得到深入的研究.另外,对不同的客体信息进行维持是否对应不同的认知加工模式,以及视觉工作记忆维持阶段负荷效应的神经基础还没有得到广泛的研究.因此,本研究从面孔信息和房子信息的视觉工作记忆任务出发,采用行为实验和功能核磁共振技术探究视觉工作记忆维持阶段中对不同记忆内容的行为表现、大脑激活强度、视觉皮层解码机制及其负荷效应,为大脑功能方面对于视觉工作记忆内容的表征提供具有价值的影像学依据.研究结果表明,被试在对复杂客体的视觉工作记忆任务中表现出视觉工作记忆容量的有限性和负荷效应,可以通过双侧海马旁、双侧顶内沟的激活强度和V4、双侧梭状回、双侧颞上沟的信息解码正确率区分视觉工作记忆维持内容.另外,双侧壳核的激活强度则体现了视觉工作记忆负荷效应.

Impaired Face Perception in Individuals with Autism Spectrum Disorder: Insights on Diagnosis and Treatment

Autism spectrum disorder(ASD)is a neurodevelopment disorder characterized by impaired social interaction and communication along with restricted and repetitive behavior.For a long period of time,ASD was considered to be a rare mental disorder,with a prevalence of less than1/100,000.However,the prevalence of diagnosed ASD has increased rapidly in recent years to

Neural plasticity in high-level visual cortex underlying object perceptual learning

与集中的训练，人能在各种各样的感性的任务完成出色的行为的改进。这现象，称为的感性的学习，长被看作了感觉神经系统的粘性的一个特点。不令人惊讶地，高级视觉例如目标感觉，能被感性的学习也改进。这里，我们考察调查在目标上训练选择外皮的效果的最近的 psychophysical， electrophysiological，和 neuroimaging 研究，例如猴子晚辈时间的外皮和人的侧面的枕骨的区域。证据证明学习在单个神经原水平或 neuronal 人口水平在目标选择导致增加。这些调查结果显示在人的那张高级视觉外皮是高度塑料、视觉的经验能强烈塑造这些区域的神经功能。在评论的结束，我们在这个区域讨论几个重要未来方向。