Fig. 4.

Experimental arrangement of recording and stimulating electrodes and the effects of coronal cuts. A: Nissl-stained sagittal section showing vertical tracts left by the bipolar recording electrodes and indicated by the details labeled Cx1-Cx4. Position of the stimulating electrode (S), anterior to Cx1, is indicated. Because it was not in the same plane as the recording electrodes, the tract is not visible. B: average (n = 10) evoked potentials from the same mouse in the control (INTACT) situation showing absence of response across the cut in Cx3 and Cx4 (CUT). C: plots of the average from all animals of the peak crosscorrelation after the cut (dark lines and triangles) for fast (top plot) and slow (bottom plot) activity. For comparison, the values of the WT and KO (from Fig. 3) are plotted in light gray. *Significant differences (t-test) in WT mice before and after transcortical cuts.