T. Wagner et al., The superior olivary complex is necessary for the full expression of the acoustic but not tactile startle response in rats, BEH BRA RES, 108(2), 2000, pp. 181-188
The acoustic startle response (ASR) in rats is mediated by an oligosynaptic
pathway from the cochlea via the brainstem to spinal and cranial motoneuro
ns. The present study tested whether the superior olivary complex (SOC) pla
ys a role in the mediation of the ASR. The SOC receives auditory informatio
n from the ventral cochlear nuclei and projects to the caudal pontine retic
ular nucleus (PnC), the sensorimotor interface of the ASR. Axon-sparing exc
itotoxic lesions of the SOC strongly reduced the ASR amplitude and slightly
prolonged ASR onset and peak latencies. The integrity of PnC which is adja
cent to the SOC was confirmed by testing the tactile startle response which
was not affected by SOC lesions. We suggest that the SOC is necessary for
a full expression of the ASR and discuss possible auditory input structures
involved in the mediation of the ASR. (C) 2000 Elsevier Science B.V. All r
ights reserved.