In recent years, Suga and his collaborators have made fundamental discoveries in his bat research on plasticity, which deals with changes in the auditory system of the brain in response to stimuli and associative learning. Plasticity is how circuits in the brain organize and reorganize in response to learning and memory, body changes, novel sensory stimuli and damage to the brain. Gaining a fuller understanding of plasticity can help researchers develop strategies and therapies for victims of stroke and other brain damage. In bats, Suga and his collaborators have found that auditory information moves from the inner ear all the way to the cerebral cortex at the top of the brain. This is the ascending system.
Signals also come down from the cerebral cortex to the inner ear, forming multiple feedback loops.
This is the descending, or corticofugal, system. It is this system that modulates the signal processing in the ascending system, and it plays a very important role in plasticity. Suga and his collaborators are churning out results quickly and have recently published a number of key papers with still more due out this year. His pioneering work with the auditory system of bats has provided new insights at a time when both the research community and students are highly interested in the brain. While Hiroko returns to Japan every other year to visit relatives, her husband visits less often, usually in conjunction with a scientific meeting.