Fig. 1.

ACPD (500 μm in pipette) activates chattering cells in a previously quiescent slice (A,a). Expanding the extracellular recording (A,b) reveals high-frequency repetitive bursts. The interburst frequencies are thebottom data points in A,c, and the intraburst frequency of this is >300 Hz (A,c,top traces). The developmental progression of the incidence of chattering is displayed in C. Thebars represent the percentage of bursting neurons observed in the different aged animals or in B how the incidence of chattering was affected by different concentrations of extracellular Ca²⁺. The numbers above the bars (B, C) represent the number of chattering cells responsive to ACPD and the total number of units recorded.