Blumenthal T D, Schicatano E J, Chapman J G, Norris C M, Ergenzinger E R
Department of Psychology, Wake Forest University, Winston-Salem, NC 27109, USA.
Percept Psychophys. 1996 Jan;58(1):73-80. doi: 10.3758/bf03205477.
The present studies investigated the relationship between prepulse effects on the modification of the brainstem startle reflex and magnitude estimates of startle-eliciting stimuli. In Experiment 1, startle eyeblink responses were elicited in 24 students, half of whom were instructed to estimate the loudness of the startle stimulus (actual intensities of 80, 90, and 100 dB) and half of whom were instructed to estimate the magnitude of their eyeblink. When weak acoustic prepulses preceded the startle-eliciting stimulus, eyeblink amplitude was inhibited, and estimates of response magnitude decreased, but estimates of startle stimulus magnitude decreased only when 100-dB startle stimuli were presented. In Experiment 2, the same startle stimuli were preceded on some trials by a vibrotactile prepulse to the hand. In conditions in which startle amplitude was inhibited, startle stimulus magnitude estimates were not affected. This suggests that the effect of acoustic prepulses on 100-dB startle stimuli in Experiment 1 may have been due to loudness assimilation, an effect independent of the prepulse inhibition of startle responding.
本研究调查了预脉冲对脑干惊吓反射调节的影响与惊吓诱发刺激的强度估计之间的关系。在实验1中，对24名学生诱发了惊吓眨眼反应，其中一半学生被要求估计惊吓刺激的响度（实际强度为80、90和100分贝），另一半学生被要求估计他们眨眼的幅度。当弱声预脉冲先于惊吓诱发刺激出现时，眨眼幅度受到抑制，反应幅度估计值下降，但只有当呈现100分贝的惊吓刺激时，惊吓刺激强度估计值才会下降。在实验2中，在一些试验中，相同的惊吓刺激之前会对手施加振动触觉预脉冲。在惊吓幅度受到抑制的情况下，惊吓刺激强度估计值不受影响。这表明，实验1中声预脉冲对100分贝惊吓刺激的影响可能是由于响度同化，这是一种独立于预脉冲对惊吓反应抑制的效应。
