Figure 1.

The in vivo/in vitro preparation. (A) Schematic of a lateral view of the rat cortex), showing the somatotopic map. The border between the forepaw and lower jaw areas is indicated by the filled circle; the dotted lines delineate the orientation and location of a 400-μm-thick slice used for the in vitro analysis. C: caudal, R: rostral, N: medial, L: lateral. (B) Schematic coronal section from rat S1 showing the recording and stimulating configuration in a normal slice. The black circle represents the dye mark defining the location of the forepaw/lower jaw border (dotted line) determined in vivo, the schematic neuron is the neuron recorded from, and the 2 squares the sites of electrical stimulation across the border (“CB stim,” gray) and not across the border (“NCB stim,” black) from the neuron. L4 indicates the position of layer 4 and the arrow points to the cut used to isolate the supragranular layers. (C) Schematic coronal section showing the recording and stimulating configuration in a control slice. Abbreviations are as in (B).