Figure 5.

Optogenetic stimulation drives LC-NA burst-pause activity. A, Peristimulation time histogram and raster plots of an example LC-NA neuron that exhibited both laser-evoked firing and poststimulation pauses. B, Average z-score normalized responses to 3, 10, and 30 Hz stimulation across all nine recorded LC-NA units. The shaded area represents mean population activity ± SEM. C, All LC units exhibited laser-evoked increases in firing during the 0.5 s laser pulse train, and the majority additionally exhibited a pause in firing following train offset. D, More units exhibited pause responses as the stimulation frequency increased from 3 to 30 Hz. E, Across the population of LC units, laser stimulation at 10 Hz, but not at 3 or 30 Hz, significantly increased firing rates during the initial 200 ms after train onset. *p < 0.05, one-sample t test. F, Increasing stimulation frequency resulted in an increase in pause durations. *p < 0.05, Bonferroni-corrected t tests.