Spatial distributions of all recorded units (A) and of those that respond to flash stimulation (B). The recording sites numbered as 1 to 8 are at 200-μm increments both vertically and horizontally. Recording sites span the entire cortical depth from layer I to layer VI. The entire array is in primary visual cortex (V1M); frontal is to the left and caudal is to the right. Data were pooled from all experiments (N = 6) and all states (0 to 8% desflurane). At some of the recording sites, more than one unit was found.