延缓go/no-go行为作业相关的猴尾核神经元电活动

NEURONAL ACTIVITY OF THE MONKEY CAUDATE NUCLEUS RELATED TO A DELAYED GO/NO-GO TASK

本工作观察了猴（Ｍａｃａｃａｍｕｌａｔｔａ）在执行延缓ｇｏ／ｎｏ－ｇｏ行为作业时的展核神经元电活动、在记录到的２３１个行为作业相关的尾核单位中，有１７９个被监别为与某些认知功能有关。这些尾核单位的大多数在暗示信号（ＥＣＳ—ｕｎｉｔ，ｎ＝３１）或反应触发信号（ＥＴＳ—ｕｎｉｔ，ｎ＝７２）出现之前呈现逐渐增强的放电活动，并持续到相应的信号出现。这类尾核单位的活动可能参与选择性注意过程，也可能参与一种期待（随后的事件）或准备（随后的反应）状态的形成。另一类尾核单位的活动在延缓用间持续增强（ＡＤＰ－ｕｎｉｔ，ｎ＝５２），并且这种持续增强的活动与随后的反应正确与否相联系，可能在暂时保持信息的工作记忆过程中起着重要作用。此外，本研究中坯观察到一类与行为作业的多个成分相关的尾核单位活动（ＭＴ－ｕｎｉｔ，ｎ＝２４），这类单位活动可能反映了信息在尾核内的会聚和处理过程。因此，本研究的结果为尾核参与注意和期待，尤其是信息的暂时保持等复杂的认知功能提供了进一步的实验证据。

In the present study, unit activity of the caudate nucleus was investigated in rhesus monkeys (Macaca mulatta) performing a delayed go/ no-go task in which movement or no-movement responses were required depending on the position of a light cue. of the 231 task-reacted caudate units, 179 were identified as units related to some cognitive functions. Most of them were activated before the cue (ECS-uait, n=31) or trigger signal (ETS-unit, n=72), and their activities gradually increased and lasted until the cue or trigger signal appeared. These units may he involved in selective attention, or in establishing a waiting or ready state for subsequent event or response' The other group of caudate units (ADP-unit, n=52), the activities of which increased during the delay period and depended on the correctness of subsequent behavioral response,may play an important role in motor working-memory for temporary retention of cue signal and its behavioral significance.Besides, the unit activity associated with two or more components of the task (MR-unit, n=24) were also investigated, and it may reflect multiple signaling processes in the caudate nucleus. Our present work provided further evidence for the role of the caudate nucleus in complex cognitive functions such as attention, expectation, and working-memory.