Prescription opioid overdose is increasing at a rapid rate. Respiratory depression is the primary cause of death from opioid overdose, yet surprisingly, very little is known about the mechanisms of opioid-induced respiratory depression. Breathing, like other motor behaviors, is coordinated by a central neural network. The goal of the Levitt Lab is to understand how opioids modulate neurons in the respiratory network to cause breathing disturbances. A variety of cellular and systems level approaches — including brain slice electrophysiology, single unit and whole nerve recordings from a unique preparation with an intact respiratory network and in vivo-like respiratory cycle, and plethysmography in awake animals — are used to achieve this goal.