The temperature gradient in the cat visual cortex, measured along the center of the cooling probe, is consistently ~5°–6°C/mm (see for control experiments and review Huang et al., 2007; cf. also Casanova et al., 1997). Indeed, when the temperature of the probe confined to PTV was lowered to ~10°C, the tissue within 2 mm radius from the edge of the probe was between 10°C and 20°C. At this range, the generation of neuronal action potentials (spikes) becomes unreliable (Volgushev et al., 2000). Furthermore, in control experiments we (Huang et al., 2007) have found that when the probe was cooled to ~10°C, the spike-activity have largely ceased not only in PTV directly under the probe but also in parts of the cortex in the immediate proximity (2 mm) of the probe’s edge. Overall, the spike-activity silenced region included parts of areas 20a and 20b located on the ventro-lateral aspect of cerebral hemispheres, PS area (Updyke, 1986) and parts of areas 17 (V1), 18 (V2), 19 (V3) and 21b (Figure 1A). All areas 19 and 17 neurons in which the effects of PTV inactivation have been studied had their RFs located along the visual streak. In parts of areas 18, 19 and 21b (Figure 1A) affected by the spread of cooling, the upper contralateral visual field is represented (Tusa et al., 1979; Tusa and Palmer, 1980) while area PS contains representation of the lower contralateral visual field (Updyke, 1986). Feedforward and to a lesser extent, feedback connections between visuotopically organized cortical areas, appear to be confined to their visuotopically corresponding regions (Salin and Bullier, 1995; Dreher et al., 1996; Morley et al., 1997). Consistent with this, reversible inactivation of the higher-order areas does not seem to affect responses of neurons in topographically non-corresponding parts of the lower areas (Martinez-Conde et al., 1999; Huang et al., 2007). Nevertheless, in view of the fact that there are long-range intrinsic cortico-cortical connections in cat’s areas 17 and 18 (e.g., Gilbert, 1993; Dreher et al., 2001; Chavane et al., 2011), it is remotely possible that inactivation of parts of areas 18 and 19 in which the upper contralateral visual field is represented contributes somehow to the effects observed in the present samples of areas 19 and 17 neurons.