PREPULSE RISE TIME AND STARTLE REFLEX MODIFICATION - DIFFERENT EFFECTS FOR DISCRETE AND CONTINUOUS PREPULSES
PREPULSE RISE TIME AND STARTLE REFLEX MODIFICATION - DIFFERENT EFFECTS FOR DISCRETE AND CONTINUOUS PREPULSES
复制标题
DOI：
10.1111/j.1469-8986.1989.tb03148.x
复制
发表时间：
1989-03-01
期刊：
影响因子：
3.7
通讯作者：
LEVEY, BJ
中科院分区：
文献类型：
--
作者：
BLUMENTHAL, TD;LEVEY, BJ
听觉前脉冲的上升时间是不同的，以确定是否起始瞬态的前脉冲是最重要的修改声惊吓反射。在实验1中，20毫秒长的离散prepulses，在150毫秒的前置时间，和prepulse上升时间从0.1到20毫秒变化。虽然所有prepulses导致反应幅度下降（抑制惊吓），从0.1到20毫秒的变化上升时间没有影响反射修改。这些结果表明，惊吓反应是不敏感的预脉冲上升时间的变化范围内使用。在实验2中，连续预脉冲（其中提前时间等于持续时间）。这些预脉冲有一个150毫秒的前置时间和上升时间范围从0.1到150毫秒，而其他人有一个上升时间为0.1毫秒和50至150毫秒的前置时间。结果表明，只有快速上升，50毫秒的前置时间预脉冲降低响应幅度，与其他预脉冲没有影响的幅度，相对于控制响应。上升时间的变化一般没有影响响应，但响应较大，在较长的前置时间比在较短的前置时间。反应概率被抑制快速上升的prepulses在提前时间为50至130毫秒。连同实验1的结果，这些研究结果表明，惊吓反射抑制是由一个prepulse的发病，这种抑制是不敏感的prepulse上升时间的小变化。此外，惊吓反射促进是由前脉冲的稳态部分，这种效果是敏感的前脉冲持续时间。抑制和易化效应联合收割机共同决定了反射修饰的数量和方向，这些效应具有不同的时程，提示不同的机制。有人建议，反射修改是由于激活的瞬态系统惊吓抑制和持续的系统惊吓促进。
The rise time of an auditory prepulse was varied to determine whether the onset transient of the prepulse is of primary importance in the modification of the acoustic startle reflex. In Experiment 1, 20-ms long discrete prepulses were presented at a lead time of 150 ms, and prepulse rise time was varied from 0.1 to 20 ms. Although all prepulses resulted in decreased response amplitude (inhibition of startle), varying rise time from 0.1 to 20 ms had no effect on reflex modification. These results suggest that the startle response is not sensitive to prepulse rise time changes in the range used here. In Experiment 2, continuous prepulses (in which lead time equals duration) were presented. Several of these prepulses had a lead time of 150 ms and rise times ranging from 0.1 to 150 ms, whereas others had a rise time of 0.1 ms and lead times of 50 to 150 ms. The results showed that only the fast-rising, 50-ms lead time prepulse decreased response amplitude, with the other prepulses having no effect on amplitude, relative to control responding. Rise time changes generally had no effect on responding, but responses were larger at longer lead times than at shorter lead times. Response probability was inhibited by fast-rising prepulses at lead times of 50 to 130 ms. Together with the results of Experiment 1, these findings suggest that startle reflex inhibition is determined by the onset of a prepulse, and that this inhibition is not sensitive to small changes in prepulse rise time. Also, startle reflex facilitation is determined by the steady-state portion of the prepulse, and this effect is sensitive to prepulse duration. The inhibitory and facilitatory effects combine to determine the amount and direction of reflex modification, and these effects have different time courses, suggesting different mechanisms. It is suggested that reflex modification is due to the activation of a transient system for startle inhibition and a sustained system for startle facilitation.