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自上而下的控制机制,工作记忆容量

Mechanism for Top-down Control of Working Memory Capacity
课程网址: http://videolectures.net/eccs08_compte_mftdcowmc/  
主讲教师: Albert Compte
开课单位: IDIBAPS公司
开课时间: 2008-10-17
课程语种: 英语
中文简介:
工作记忆依赖于前额叶和顶叶皮质的激活,可能与前额叶皮层施加自上而下的控制。但是,仍然没有机械描述容量限制或工作记忆中信息维护的自上而下控制。在这里,我们提出顶叶皮层的侧向抑制限制了记忆能力。然而,在高负荷时,这种抑制作用可以通过来自前额皮质的兴奋性输入来抵消,从而提高顶叶容量。我们在生物物理皮质微电路模型中计算得出这个模型,并用数学方程对其进行概念化。在fMRI研究中证实了该模型的预测。该模型提供了一个机制框架,用于理解工作记忆的自上而下控制,并指定前额叶和顶叶皮层对工作记忆容量的两种不同贡献。
课程简介: Working memory relies on the activation of both prefrontal and parietal cortex, possibly with prefrontal cortex exerting top-down control. However, there is still no mechanistic description of either capacity limitations or top-down control of maintenance of information in working memory. Here, we propose that lateral inhibition in parietal cortex limits mnemonic capacity. However, at high loads, this inhibition can be counteracted by excitatory input from prefrontal cortex, thus boosting parietal capacity. We formulate this computationally in a biophysical cortical microcircuit model, and conceptualize it in a mathematical equation. Predictions from the model were confirmed in an fMRI study. The model provides a mechanistic framework for understanding top-down control of working memory, and specifies two different contributions of prefrontal and parietal cortex to working memory capacity.
关 键 词: 额叶和顶叶皮层; 自上而下的控制; 侧抑制记忆容量限制
课程来源: 视频讲座网
最后编审: 2020-10-14:yumf
阅读次数: 55