Ramírez Isabel, Sánchez María B, Fernández María Carmen, Lipp Ottmar V, Vila Jaime
Faculty of Psychology, University of Granada, Granada, Spain.
Psychophysiology. 2005 Nov;42(6):732-9. doi: 10.1111/j.1469-8986.2005.00362.x.
Rise time and duration are two parametric characteristics of the eliciting stimulus frequently used to differentiate among psychophysiological reflexes. The present research varied the duration (study 1) and rise time (study 2) of an intense acoustic stimulus to dissociate cardiac defense and cardiac startle using the eyeblink response as the external criterion of startle. In each study, 100 participants were presented with five white noise stimuli of 105 dB under one of five duration (50, 100, 250, 500, and 1000 ms) or rise time (0, 24, 48, 96, and 240 ms) conditions. Cardiac defense was affected by stimulus duration, present only in the 500- and 1000-ms conditions, but not by stimulus rise time, present in all rise time conditions. Rise time affected blink startle, but did not selectively alter the short latency accelerative component of the heart rate response, thus questioning whether it reflects startle.
上升时间和持续时间是诱发刺激的两个参数特征，常用于区分心理生理反射。本研究通过改变强烈听觉刺激的持续时间（研究1）和上升时间（研究2），以眨眼反应作为惊吓的外部标准，来区分心脏防御反应和心脏惊吓反应。在每项研究中，100名参与者在五种持续时间（50、100、250、500和1000毫秒）或上升时间（0、24、48、96和240毫秒）条件之一的情况下，接受了五次105分贝的白噪声刺激。心脏防御反应受刺激持续时间的影响，仅在500毫秒和1000毫秒的条件下出现，但不受刺激上升时间的影响，在所有上升时间条件下均存在。上升时间影响眨眼惊吓反应，但并未选择性地改变心率反应的短潜伏期加速成分，因此对其是否反映惊吓反应提出了质疑。
