Psychiatric disorders such as Anxiety and Autism Spectrum Disorders are often characterized by a rapid and amplified arousal response to stimuli (hyperarousal), which is often followed by a motivational drive to avoid such stimuli. Our lab studies the neuronal circuits that drive hyperarousal states by monitoring neuronal activity with single-cell precision using in vivo calcium imaging techniques in both head-fixed (two-photon microscopy) and freely-moving (miniature head-mounted microscopes) mice to record and track the activity of hundreds of individual neurons with both genetic and projection specificity.