Passive exposure of adult cats to moderate-level tone pip ensembles differentially decreases AI and AII responsiveness in the exposure frequency range》.pdfVIP

Hearing Research 268 (2010) 151e162 Contents lists available at ScienceDirect Hearing Research journal homepage: /locate/heares Research paper Passive exposure of adult cats to moderate-level tone pip ensembles differentially decreases AI and AII responsiveness in the exposure frequency range Martin Pienkowski, Jos J. Eggermont* Departments of Physiology and Pharmacology, and Psychology, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada a r t i c l e i n f o a b s t r a c t Article history: Passive exposure of adult animals to a random ensemble of tone pips band limited between 4 and 20 kHz Received 8 March 2010 has been shown to suppress neural activity in primary auditory cortex (AI) to sounds in the exposure Received in revised form frequency range. In the long-term (3 months), the suppressed neurons can be reactivated by frequencies 22 April 2010 above and below the exposure range, i.e., tonotopic map reorganization occurs. The suppression can be at Accepted 21 May 2010 least partially reversed after a long period of quiet recovery, as the moderate-level exposure does not Available online 1 June 2010 impair peripheral hearing. Here we exposed adult cats, for 7e13 weeks without interruption, to two different moderate-level tone pip ensembles, in separate experiments. One exposure stimulus consisted of