Cross-correlation analysis of taste neuron pairs in rat solitary tract nucleus

1. Experiments were conducted to examine the possibility that the taste-sensitive neurons with similar taste-selectivity are preferentially innervated by common driving neurons whose taste-selectivity is also similar. 2. Multiple microelectrodes, in most cases a pair of glued electrodes, were inserted into the unilateral solitary tract nucleus (NTS) of the rat, and simultaneous recordings were made in neuron pairs responding to the four basic taste stimuli. The spike response density (RD) of each neuron during tastant stimulation was determined. Correlation coefficients of spike occurrence were calculated for each neuron pair during application of tastants and distilled water and also during spontaneous background activity. The frequency of correlated discharge (FC) of a neuron pair was measured as the area of the peak appearing on the cross-correlogram (CC). The FC value was divided by the RD value to calculate the weight of the correlated discharges in the output of each neuron (WC value). 3. Eleven pai...