Song playback and monoamine levels.

Effects of the song playback and a subject's own recent singing behavior on amounts of three monoamines and their primary metabolites (measured as pg/mg protein) in auditory processing and song control regions of the forebrain of male Lincoln's sparrows. Level of song challenge (i.e., treatment) was coded 0 for less challenging and 1 for more challenging. Statistically reliable effects (p