INTRODUCTIONType 2 diabetes （T2D） is one of the fastest growing medical conditions associated with cognitive dysfunctions. Less attention is paid to the effects of diabetes on task switching （TS）. Switching betwee...INTRODUCTIONType 2 diabetes （T2D） is one of the fastest growing medical conditions associated with cognitive dysfunctions. Less attention is paid to the effects of diabetes on task switching （TS）. Switching between tasks is a higher-order cognitive function which is executed through prefrontal cortex. Given that there are brain structural abnormalities （i.e., atrophy in cortical/subcortical gray matter volume and hyperintensities in cerebral white matter）, reduced connectivity between hippocampus and adjacent brain regions （frontal and temporal gyri）,展开更多
人类认知系统在动态环境中展现出卓越的适应性,其核心机制之一是任务切换中对无关信息的有效抑制。本研究聚焦逆向抑制的触发机制,通过改进线索呈现范式(恒定无意义线索)和任务结构(完全排除重复试次),在单义刺激与反应条件下考察任务...人类认知系统在动态环境中展现出卓越的适应性,其核心机制之一是任务切换中对无关信息的有效抑制。本研究聚焦逆向抑制的触发机制,通过改进线索呈现范式(恒定无意义线索)和任务结构(完全排除重复试次),在单义刺激与反应条件下考察任务线索对逆向抑制的驱动作用。实验发现:(1)任务线索组存在显著N-2重复代价(ABA vs CBA序列差异39 ms,p<0.05),而映射指令组无此效应;(2)项目不重复试次中逆向抑制效应更强(ηp^(2)=0.214 vs 0.390),表明抑制机制存在任务与项目双重层级;(3)线索-目标间隔时间主效应显著(500 ms vs 1000 ms差异40 ms,p<0.001),提示线索加工深度影响抑制强度。结论表明:任务线索可独立触发逆向抑制,其作用层级体现为任务层面的全局性抑制与项目层面的特异性抑制协同共存,其中项目不重复条件下的抑制效应显著增强;抑制强度受线索加工时间的动态调节,更长的准备时间通过优化任务定势重构显著提升抑制效能。展开更多
文摘INTRODUCTIONType 2 diabetes （T2D） is one of the fastest growing medical conditions associated with cognitive dysfunctions. Less attention is paid to the effects of diabetes on task switching （TS）. Switching between tasks is a higher-order cognitive function which is executed through prefrontal cortex. Given that there are brain structural abnormalities （i.e., atrophy in cortical/subcortical gray matter volume and hyperintensities in cerebral white matter）, reduced connectivity between hippocampus and adjacent brain regions （frontal and temporal gyri）,
文摘人类认知系统在动态环境中展现出卓越的适应性,其核心机制之一是任务切换中对无关信息的有效抑制。本研究聚焦逆向抑制的触发机制,通过改进线索呈现范式(恒定无意义线索)和任务结构(完全排除重复试次),在单义刺激与反应条件下考察任务线索对逆向抑制的驱动作用。实验发现:(1)任务线索组存在显著N-2重复代价(ABA vs CBA序列差异39 ms,p<0.05),而映射指令组无此效应;(2)项目不重复试次中逆向抑制效应更强(ηp^(2)=0.214 vs 0.390),表明抑制机制存在任务与项目双重层级;(3)线索-目标间隔时间主效应显著(500 ms vs 1000 ms差异40 ms,p<0.001),提示线索加工深度影响抑制强度。结论表明:任务线索可独立触发逆向抑制,其作用层级体现为任务层面的全局性抑制与项目层面的特异性抑制协同共存,其中项目不重复条件下的抑制效应显著增强;抑制强度受线索加工时间的动态调节,更长的准备时间通过优化任务定势重构显著提升抑制效能。
