An amygdalar neural ensemble that encodes the unpleasantness of pain

The emotional dimension of pain The unpleasantness of pain is an emotional phenomenon distinct from pain's sensory qualities. To study how the brain processes pain-related emotions, Corder et al. used in vivo neural calcium imaging in freely behaving mice. They identified brain circuits that respond to pain and directly tested their causal role in motivational behaviors associated with acute and chronic pain. Science , this issue p. 276