Knyazev Gennady G, Levin Evgenij A, Savostyanov Alexander N
State Research Institute of Physiology, Siberian Branch of the Russian Academy of Medical Sciences, Timakova Street, 4, Novosibirsk, 630117, Russia.
State Research Institute of Physiology, Siberian Branch of the Russian Academy of Medical Sciences, Timakova Street, 4, Novosibirsk, 630117, Russia.
Clin Neurophysiol. 2008 Mar;119(3):556-567. doi: 10.1016/j.clinph.2007.11.041.
It is not always clear whether inhibition or attention deficit underlies a failure to stop a prepared motor response. One possible way to approach this question is to resort to measures of evoked oscillations since functional correlates of different frequency oscillations are relatively well understood.
The present study examined event-related oscillations during a stop-signal task in non-clinical adults. In 25% of trials of an auditory discrimination tasks subjects had to refrain from a prepared motor response.
In successful stop trials, the Go N2 peaked later and the Stop N2 peaked earlier than in failed stop trials. Relative to successful, failed stop trials were associated with a larger N1-N2 and Go P3, and a smaller Stop P3 in the central and posterior cortical regions. The latter effect was exclusively determined by evoked delta oscillations, whereas all other frequency bands contributed to enhanced responses in failed comparative to successful stop trials.
The sum of presented evidence seems to show that success or failure to stop mostly depends on how the subject prepares for the Go and Stop stimuli in advance. If attention is more directed towards the Stop signal, the stopping succeeds, otherwise it fails.
These data may contribute to understanding the cognitive basis of successful and unsuccessful stopping performance.
在准备好的运动反应无法停止的情况下，究竟是抑制作用还是注意力缺陷起主导作用，这一点并不总是很清楚。解决这个问题的一种可能方法是采用诱发振荡的测量方法，因为不同频率振荡的功能相关性相对而言得到了较好的理解。
本研究考察了非临床成年人在停止信号任务期间的事件相关振荡。在听觉辨别任务25%的试验中，受试者必须抑制准备好的运动反应。
在成功的停止试验中，与失败的停止试验相比，执行信号（Go）N2峰出现得更晚，停止信号（Stop）N2峰出现得更早。相对于成功试验，失败的停止试验在中央和后皮质区域与更大的N1-N2和执行信号P3以及更小的停止信号P3相关。后一种效应完全由诱发的δ振荡决定，而所有其他频段在失败的停止试验与成功的停止试验相比时，都导致反应增强。
所呈现的证据总和似乎表明，停止的成功或失败主要取决于受试者预先对执行信号和停止信号的准备方式。如果注意力更多地指向停止信号，停止就会成功，否则就会失败。
这些数据可能有助于理解成功和失败的停止表现的认知基础。
