Slide 13

This summary diagram indicates that the optimal state for performance of a difficult detection task occurs at intermediate levels of arousal. The optimal state is characterized by the suppression of low frequency oscillations in synaptic activity, a hyperpolarized and stable membrane potential, and reliable sound evoked synaptic responses. We hypothesize that the brainstem/basal forebrain networks responsible for controlling brain state also control state of the peripheral nervous system, including pupil diameter. NE and ACh may play a key role in this process.