Pairing Cholinergic Enhancement with Perceptual Training Promotes Recovery of Age-Related Changes in Rat Primary Auditory Cortex

Figure 4

Training and rivastigmine impact on the overlap in A1 area responsiveness to training tones. (a) A1 maps from the same animals as in Figure 3 showing the area activated by 5 kHz (blue polygons) or 10 kHz (green polygons) tones presented at 60 dB SPL (the sound intensity during training). The dark pink polygons indicate the area of the map activated by both frequencies. (b) Difference in A1 area overlap in responsiveness to 5 and 10 kHz ± 0.3 octaves in all groups. Note how training is associated with an overall reduction in overlap in all groups. (c) Difference in A1 area responsiveness to frequencies other than 5 or 10 kHz in all groups. Note how training resulted in a relative increase of A1 area activated by nontrained tones in all groups except O-TS where the reduction in overlap (b) was driven by a relative expansion of the area responsive to 10 kHz. (d) Left: ROC analysis demonstrating the average discriminability in the pattern of A1 activation for 5 and 10 kHz tones presented at 60 dB SPL. Right: ROC analysis demonstrating the average discriminability in the pattern of A1 activation for 10 and 20 kHz tones presented at 60 dB SPL. Note how training decreases the AUC in the O-TS group only. (e) Maximal performance (d-prime) on behavioral training plotted against AUC (5 versus 10 kHz) for all groups. Scale bar represents 1 mm. D: dorsal; C: caudal; R: rostral; V: ventral (Y-UT: , recorded sites = 435; Y-TS: , recorded sites = 257; Y-TR: , recorded sites = 312; O-UT: , recorded sites = 412; O-TS: , recorded sites = 261; O-TR: , recorded sites = 249). Values shown are mean ± SE. : : -test.

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