Figure 2.

Two computations that govern behavioral context in auditory cortex. During locomotion (left), evidence suggests that top-down inputs from the motor cortex (black solid line) drive the activity of PV+ interneurons which suppress the activity of pyramidal neurons. These same inputs may also activate somatostatin neuron (black dashed line, hypothetical). At the same time, ascending cholinergic neuromodulation (red lines) works on the same cell types but potentially in non-overlapping neurons. During task engagement (right), evidence suggests that all three major interneuron subtypes are co-activated by ascending cholinergic neuromodulation (red lines). Top-down inputs from the frontal cortex are known to modulate PV+ interneurons (black solid line) while potentially also operating on other interneuron subtypes (black dashed line, hypothetical).