Figure 3. Suppression of delay-period activity in auditory cortex (AC) by optogenetic inhibition of pyramidal neurons impaired auditory working memory (WM) performance.

(a) Histology image showing the expression of AAV-CaMKIIα-eNpHR3.0-eYFP in AC. (b) Activity suppression efficiency revealed by optetrode recording in vivo. (c) Suppressing AC activity during the delay period of WM task decreased performance, with a substantial increase in false alarm (FA) rate and a small decrease in hit rate. Top: schematic of optogenetic stimulation during the delay period of WM task. The green rectangle indicates the period of inactivation. For the bottom panel, gray lines indicate individual mice; black indicates mean ± s.e.m. Circles indicate individual mice. *p<0.05, **p<0.001, t-test. (d) As in (c) with control virus injection. The photostimulation of AC with control virus injection during the delay period did not affect the behavior. N.S.: not significant. (e) Suppressing AC delay-period activity decreased the performance in the four tones auditory WM task with a decrease in FA rate and no change in hit rate. See Figure 3—source data 1 for more details.

Figure 3—figure supplement 1. Optogenetic suppression of auditory cortex during the stimulus epoch dramatically reduced the animals’ ability to perform the working memory task.