Working memory dysfunction may be central to neurocognitive deficits in schizophrenia. Maintenance of visual information in working memory, or visual short-term memory (vSTM), is linked to general cognitive dysfunction and predicts functional outcome. Lateralized change-detection tasks afford investigation of the contralateral delay activity (CDA), a useful tool for investigating vSTM dysfunction. Previous work suggests “hyperfocusing” of attention in schizophrenia, such that CDA is increased when a single item is maintained in vSTM but reduced for multiple items. If observed early in the disease, vSTM dysfunction may be a key feature of schizophrenia or target for intervention. We investigated CDA during lateralized vSTM of one versus three items using sensor-level electroencephalography and source-level magnetoencephalography in 26 individuals at their first episode of schizophrenia-spectrum psychosis (FESz) and 26 matched healthy controls. FESz were unable to modulate CDA with increased memory load – high-load CDA was reduced and low-load CDA was increased compared to controls. Further, sources of CDA in posterior parietal cortex were reduced in FESz and indices of working memory were correlated with neurocognitive deficits and symptom severity. These results support working memory maintenance dysfunction as a central and early component to the disorder. Targeted intervention focusing on vSTM deficits may be warranted to alleviate downstream effects of this disability.

工作记忆功能障碍可能是精神分裂症神经认知缺陷的核心。维持工作记忆或视觉短期记忆 (vSTM) 中的视觉信息与一般认知功能障碍有关并预测功能结果。横向变化检测任务提供对侧延迟活动 (CDA) 的调查，这是调查 vSTM 功能障碍的有用工具。以前的工作表明精神分裂症中注意力的“过度集中”，这样当单个项目在 vSTM 中保持时 CDA 增加，但在多个项目中减少。如果在疾病早期观察到，vSTM 功能障碍可能是精神分裂症的一个关键特征或干预目标。我们使用传感器级脑电图和源级脑磁图在 26 名首次发作精神分裂症谱系精神病 (FESz) 和 26 名匹配的健康对照者的单项或三项侧化 vSTM 期间研究了 CDA。FESz 无法通过增加的记忆负载来调节 CDA——与对照组相比，高负载 CDA 减少，低负载 CDA 增加。此外，FESz 中后顶叶皮层中 CDA 的来源减少，工作记忆指数与神经认知缺陷和症状严重程度相关。这些结果支持工作记忆维持功能障碍是该障碍的核心和早期组成部分。可能需要针对 vSTM 缺陷进行有针对性的干预，以减轻这种残疾的下游影响。