Fig. 6.
The local inhibitory network within LMAN is needed to maintain a high degree of song selectivity. A,Spontaneous activity was recorded sequentially in two cells from a single bird, one before BMI application (pre) and the other afterward (post), first when BMI-induced bursting activity was evident (0.5 hr) and then after washout when bursting had ceased (2 hr; QX-314 was used in the second recording). This comparison across two cells is possible because all cells within a single bird exhibited similar temporal response profiles to song. B, Although significant responses to BOS were present only before BMI application and after washout, peaks in the averaged traces during BMI-induced disinhibition often coincided with song-induced peaks in the control condition (arrows; cells and times as described inA). C,d′ measures of selectivity during and after BMI treatment are plotted as a function of Vrest (n = 10 cells; 3 spiking cells indicated with black and grayarrows; 7 QX-314 cells indicated withgrayarrows only).