Neural Discrimination of Complex Natural Sounds in Songbirds
Speaker: Dr. Kamal Sen , Neural Coding Laboratory, Hearing Research Center, Boston University
Relevant URL: http://www.csail.mit.edu/events/eventcalendar/calendar.php?show
Discrimination and recognition of complex natural stimuli is a fundamental problem that arises in a wide variety of fields e.g., neuroscience and computer science. In neuroscience an important problem is to understand how animals and humans discriminate between complex sounds e.g., vocal communication sounds of two different individuals. In computer science, speech recognition algorithms must solve a similar problem. Moreover, such discrimination must often be performed in noisy environments, e.g., a cocktail party. How does the brain solve this problem? Currently, relatively little is known about the neural basis for complex sound discrimination and recognition. An attractive model system for investigating this question is the songbird, which shows striking analogies to humans in the context of speech. In this talk, I will describe our ongoing work on the neural discrimination of birdsongs in field L, the analog of primary auditory cortex, in zebra finches. I will present some of our findings on the accuracy and time-scales of neural discrimination, sensitivity vs. invariance to stimulus parameters e.g., intensity, and then discuss how we are extending this paradigm to investigate more complex auditory scenes, e.g., a cocktail party.