Fig. 9.

Responses of multisensory neurons to pairs of cross-modal and within-modal stimuli were similar in noise-reared animals. (A) On the left are shown unisensory and multisensory responses of a neuron from a noise-reared animal that were elicited by visual stimuli of low, medium and high effectiveness (the auditory response was insensitive to stimulus intensity, see text). Note the absence of response enhancement to the cross-modal stimulus pair at any level of stimulus effectiveness. This is typical of responses to pairs of within-modal stimuli as shown by the example on the right. (B) Population data of responses to these stimulus configurations are displayed using the contrast index (+ 1 and −1 indicate responses greater or less than those to the most effective component stimulus – the best unisensory response). Noise, neurons from noise-reared animals; normal, neurons from normally reared animals. Other conventions are the same as in previous figures. Note that in the noise-reared condition responses to cross-modal stimuli overlapped those from within-modal stimuli, and were far lower than expected based on the function from the normally reared condition.