Figure 3.

Effects of inactivation of PL, IL, VS, or BLA on avoidance and passive fear responses. A, Inactivation of PL with muscimol impaired avoidance but did not alter freezing or suppression (MUS, n = 17; SAL, n = 18). B, Inactivation of IL did not impair avoidance but increased freezing and suppression (MUS, n = 13; SAL, n = 16). C, Inactivation of VS impaired avoidance and increased freezing (MUS, n = 8; SAL, n = 12). D, Inactivation of BLA impaired avoidance and decreased both freezing and suppression, consistent with loss of the tone–shock association (MUS, n = 8; SAL, n = 10). Data are presented for the first trial of Day 11. *p < 0.05; **p < 0.01, Student's t test (unpaired, two-tailed). The inset graphs indicate the time (in seconds) spent on the platform during the tone. Atlas figures indicate placements of injector tips.