Response characteristics of the CN neurons to static visual stimulation.

Each panel of the figure contains a PSTH (top) and a raster plot (bottom) to represent the activity of a neuron. Panels A and B show the activity of a PAN, panels C and D show the firing pattern of a HFN. A and C show the gross activities, B and D show the net activity change after the subtraction of the background activity. The vertical black lines denote the boundaries between the different phases of the paradigm: fixation phase (-500 to 0 ms), static visual stimulation (0 to 200 ms), dynamic visual stimulation (200 to 1200 ms), reward phase (1200 to 1700 ms). Note the phasic response of the PAN to static stimulation (A,B). The activity pattern of the presented HFN (C,D) is more complex: increased activity can be observed not only to random dot patterns, but also to optic flow and during the reward phase. The abscissa denotes the time in milliseconds. The ordinate denotes the number of successful trials and the activity of the neuron. The lowest number is the number of the successful trials, the next is the average discharge during the whole recording and the highest number is the stimulated activity (Hz). The continuous grey curve is a smoothed curve of the activity, and the dashed grey lines indicate ± 2 SD of the average background discharge rate in the whole recording.