The expression of prepulse inhibition of the acoustic startle reflex as a function of three pulse stimulus intensities, three prepulse stimulus intensities, and three levels of startle responsiveness in C57BL6/J mice.
Behavioural Brain Research. 2005-09-01; 163(2): 265-276
DOI: 10.1016/j.bbr.2005.05.013
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Yee BK(1), Chang T, Pietropaolo S, Feldon J.
Author information:
(1)Laboratory of Behavioural Neurobiology, Swiss Federal Institute of Technology
Zurich, Schwerzenbach, Switzerland.
Using the acoustic startle reflex, prepulse inhibition (PPI) is typically
demonstrated by the interaction between two auditory stimuli presented in close
temporal proximity. When a startle-eliciting pulse stimulus is shortly preceded
by a weak prepulse stimulus, the reaction to the former is attenuated in
comparison to when the pulse stimulus is presented alone. The present experiment
evaluated the influence of different prepulse and pulse intensities upon the
expression of PPI by additionally taking into account individual differences in
startle reactivity. To this end, we subdivided a cohort of 102 mice into three
subsets of equal size differing in startle responsiveness, and evaluated PPI
using three levels of prepulse stimulus in combination with three intensities of
pulse stimulus. Our results revealed additive as well as complex interactive
effects amongst individual’s reactivity, pulse intensity and prepulse intensity.
At the same time, additional issues concerning the quantification of PPI are
highlighted, especially when startle reactivity differs considerably between
comparison groups. We concluded that the variation in pulse intensity represents
a valuable addition to PPI assessment in general, and especially in genetically
modified mice.