Precedence-effect-induced enhancement of prepulse inhibition in socially reared but not isolation-reared rats.
Attention to a prepulse presented shortly before a startling stimulus enhances prepulse inhibition (PPI) of startle in normal people, but not in schizophrenics. Fear conditioning for the prepulse enhances PPI in socially reared, but not isolation-reared, rats. In humans, selective attention to acoustic signals against masking can be facilitated by precedence-effect-induced perceived spatial separation between the signal and the masker. This study investigated whether perceived spatial separation between a prepulse and a noise masker enhances PPI in socially reared rats and isolation-reared rats. The results show that both PPI and conditioning-induced PPI enhancement were larger in socially reared rats than in isolation-reared rats. More important, in socially reared, but not isolation-reared, rats, a further PPI enhancement was induced by precedence-effect-induced perceived separation between a prepulse and a masker only after the prepulse became fear conditioned. Thus, perceived separation facilitates normal rats' attention to a conditioned prepulse and enhances PPI. Isolation rearing impairs rats' ability to attend to ecologically significant acoustic events.
Du
Yi
Y
Peking University, Beijing, China.
Li
Jingyu
J
Wu
Xihong
X
Li
Liang
L
D000161:Acoustic Stimulation / Q000379:methods; D000704:Analysis of Variance; D000818:Animals; D001288:Attention / Q000502:physiology*; D001522:Behavior, Animal; D003214:Conditioning, Classical; D008297:Male; D009433:Neural Inhibition / Q000502:physiology*; D010146:Pain / Q000209:etiology / Q000503:physiopathology; D010147:Pain Measurement; D011571:Psychoacoustics; D051381:Rats; D017207:Rats, Sprague-Dawley; D013216:Reflex, Startle / Q000502:physiology*; D012934:Social Isolation / Q000523:psychology*; D013057:Spectrum Analysis