Table 4.

Summary of changes in auditory cortices.

Author(s)	Species	Etiology	Deafness onset	Change(s) observed
Raggio and Schreiner, 1999	Cat	Ototoxic	Day 16–21	↑ in area of A1
				↑ excitability/↓ inhibition of A1 neurons
				No change in rate- or latency-intensity functions
				Tonotopy is lost
Kral et al., 2002	Cat	Congenital	Day 0	No change in size of A1
				Immature connections to deeper layers
				Coarse tonotopy maintained
Wong et al., 2013a	Cat	Ototoxic	Early late	↓↓↓ in area of A1
				↓ in area of A1
Wong et al., 2013b	Cat	Congenital	Day 0	↓↓↓ in area of A1
Kral et al., 2006	Cat	Congenital	Day 0	↓ in # of primary dendrites
				↓ in span of dendritic trees
Hartmann et al., 1997	Cat	Congenital	Day 0	No change in laminar structure
Stanton and Harrison, 2000	Cat	Ototoxic	Day 6	No change in thalamocortical projections to A1
Klinke et al., 1999	Cat	Congenital	Day 0	Inputs to layers III/IV remain
				Connections to supergranular layers remain
Kral et al., 2000	Cat	Congenital	Day 0	Immature connections to deeper layers
Kral et al., 2003	Cat	Congenital	Day 0	↑ spontaneous firing rate
Kotak et al., 2005	Gerbil	Cochlear ablation	Dat 10	↑ excitability/↓ inhibition of A1 neurons
Kral et al., 2005	Cat	Congenital	Day 0	↑ excitability/↓ inhibition of A1 neurons
				↓ response to electrical stimulation
Raggio and Schreiner, 1994	Cat	Ototoxic	Day 16–21	No change in rate- or latency-intensity functions
Tillein et al., 2010	Cat	Congenital	Day 0	Binaural feature sensitivity is maintained
				Coarse tonotopy maintained
Kral et al., 2001	Cat	Congenital	Day 0	Coarse tonotopy maintained
Hartmann et al., 1997	Cat	Congenital	Day 0	Coarse tonotopy maintained
Fallon et al., 2009	Cat	Ototoxic	Day 17	Tonotopy is lost
Kotak et al., 2007	Gerbil	Cochlear ablation	Day 10	No LTP in layer V neurons

LTP, Long-term potentiation; A1, Primary auditory cortex.