Figure 7. Effects of lesions on shock-induced changes to foraging and activity patterns.

(a) Raw number of pellets obtained, (b) number of pellets obtained normalized to baseline average, (c) raw activity (distance traveled in m), and (d) activity normalized to baseline average of amygdala-lesioned (AMYX; n = 7) rats exposed to baseline (black) and unsignaled nocturnal shock (red) conditions. AMYX animals maintained their nocturnal feeding/activity behavior during unsignaled nocturnal shock. (e) Raw number of pellets obtained, (f) number of pellets obtained normalized to baseline (black) average, (g) raw activity (distance traveled in m), and (h) activity normalized to baseline average of SCN-lesioned (SCNX; n = 8) rats exposed to baseline (black), unsignaled nocturnal shock (black circles with red outline), and unsignaled diurnal shock (open circles with red outline) conditions. SCNX animals slightly preferred feeding in the dark phase during baseline, which abolished during unsignaled nocturnal shock. When exposed to unsignaled diurnal shock, SCNX rats’ feeding behavior remained arrhythmic. Error bars indicate SEM.