In our study, inactivation of the entire ipsilateral PTV cortex resulted in the reduction (albeit rarely significant) of background spike-activities of simple and complex area 19 cells. Also during inactivation, in a quarter (significant) to half of the sample, the magnitude of spike-responses was reduced. Interestingly, inactivation of higher-order pattern/form-processing areas 21a and 19, reciprocally and strongly interconnected with area 17, results in reduction in the magnitude of spike-responses to optimal visual stimuli in a great majority of affected area 17 neurons (Wang et al., 2000). The excitatory nature of feedback cortico-cortical connections is not restricted to pattern/form processing stream. In particular, reversible inactivation of cat’s motion area—posterior middle suprasylvian cortex (Galuske et al., 2002) caused reduction in the signal strength in orientation and direction maps in the parastriate cortex (area 18, V2). Similarly, cooling motion-processing medio-temporal (MT) cortex of macaque monkeys results in reductions of magnitude of spike-responses of neurons in the ipsilateral areas V1, V2 and V3 (Hupé et al., 2001b).