Song Learning and Fluctuating Brain Estrogens

University Of Massachusetts Amherst, Amherst MA

Investigators

Abstract

Learning is dependent on the actions of small molecules in the brain, called neuromodulators. Common neuromodulators include dopamine and serotonin, which are involved in learning and memory in animals from worms to humans. The current work will explore a recently-identified neuromodulator system: the production of estrogens within the brain. A series of studies will examine how brain estrogen production may support learning complex motor sequences. Understanding the brain's ability to produce its own supply of estrogens may open up new perspectives on cognition, memory, and the function of basic neural circuits that are common among vertebrate animals. Estrogens are typically considered reproductive hormones secreted by the ovaries, yet it is now clear that estrogens are produced within the brain itself, in both males and females. A combination of approaches will test the hypothesis that estrogens can be produced within brain circuits to rapidly enhance the consolidation of recent experiences. Songbirds provide an exceptional opportunity to study the underlying brain mechanisms for the learning and memorization of song. There are substantial neural and behavioral parallels between song learning in songbirds and language/speech learning in humans. Juvenile songbirds typically learn songs from an adult tutor during a brief critical sensory period. A recently-optimized method enables the measurement and manipulation of brain estrogens in behaving songbirds while they learn from song tutors and consolidate new songs. Because estrogens have been associated with learning and memory in many animals, including human beings, this research therefore has potential for significant impacts. The work will also involve training students from underrepresented groups in multidisciplinary, integrative research and outreach activities.