Skill learning, like speaking, includes learning behaviors based on practice. A fundamental question of basic neuroscience is: how do learners measure success in learning, or how does the brain evaluate behavioral outcomes in relation to a goal? For example, parents serve as vocal tutors by uttering mature sounds (the goals) which human infants must learn to reproduce as they practice babbling. Skill learning is thought to involve goal-directed evaluation of self-generated behavioral outcomes. The child evaluates how closely their babbling matches their parents’ mature sounds. This gradually shapes brain circuits to select appropriate actions. In this case, as infants compare their own babbling sounds to the mature goal sounds made by parents, they gradually learn to emulate those mature speech sounds. Vocal learning in songbirds provides a powerful model for studying how specific neural circuits mediate such experience-dependent skill learning during development. Like human infants, young songbirds engage in a goal-oriented process in which evaluation of vocal utterances against a memory of goal sounds learned from a tutor guides gradual acquisition of learned vocal behavior. As in other forms of skill learning, successful acquisition requires neural circuits to carry out comparisons of self-generated behavioral feedback to goal representations. These studies will create new knowledge of how neural circuits mediate skill learning. This new knowledge will be used to help in developing lesson plans for elementary-school students in areas with high proportions of under-represented minorities and training programs for teachers in order to advance science education and literacy.
The objective of this research project is to investigate whether specific subcircuits within cortico-basal ganglia pathways mediate distinct aspects of goal-directed skill learning. Using vocal learning in songbirds as an experimental model, the investigators will test the role of specific neural circuits in evaluating self-generated actions against a goal behavior as animals refine their motor output. Juvenile songbirds learn a behavioral goal (memorized vocal sounds from a tutor) and produce variable behavioral output (babbling) during a process of trial-and-error learning in which actions that match the learned goal sounds are gradually strengthened. The research team will record neural activity in juvenile songbirds during development as they are actively engaged in learning; our strategy is to record from distinct subgroups of neurons identified by their selective tuning to either a neural representation of the goal or to feedback of self-generated behavior as juvenile birds begin to refine their behavioral output. They posit that these two neural signals of goal-directed learning give rise to distinct subcircuits as part of the mechanism underlying action-outcome evaluations. One major prediction is that cortical neurons that are selectively tuned to the memorized goal representation provide a filter for identifying behavior that matches the goal, and convey this information to the basal ganglia. These data will provide an important test of how goal-similar actions are identified and processed in cortical circuits and their downstream targets.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
