NON-TECHNICAL ABSTRACT Proposal Number: 9809883 Experiential Influences on Perceptual, Communicative, and Neural Capacities Meredith J., King, Andrew P. The aim of the research is to explore the effects of differences in social experience on the development of vocal communication through studies of song learning in birds. Three objectives are outlined. First, the influence of adult social models on juvenile learners will be examined by manipulating the nature of adult stimulation. Measures of the effects of social influence include vocal growth in the young, use of signals, and competence as adults. Second, female perceptual preferences for vocal signals will be studied to explore modifiability in receivers. Measures include responsiveness to vocal playback and discrimination of potential mates. Neural studies of the avian forebrain are included to relate brain organization to vocal comprehension in females and to social competence in males. The results of the work should advance knowledge of the effects of early social environments on vocal and perceptual learning, learning that is fundamental to an individual's success. This topic has broad implications for many species, including humans, as avian vocal learning is one of the premier models for identifying potential mechanisms of language learning. Of special significance is the possibility of identifying previously ignored sources of instruction including visual stimulation. The coordinated studies of brain and behavior also set the stage for measuring how behavioral experiences affect brain growth itself.