Kamal Sen, Ph.D.

Associate Professor, Biomedical Engineering
Director of Graduate Admissions, Biomedical Engineering

Hearing Research Center
Natural Sounds and Neural Coding Laboratory

M.A., Ph.D., Physics, Brandeis University
B.A., Physics, Bates College

Phone: (617) 353-5919; Fax: (617) 353-6766
Email: kamalsen@bu.edu
Office: ERB 414B; Office hours: By appointment

Research Interests

How do neurons in the brain encode complex natural sounds? What are the neural substrates of selectivity for and discrimination of different categories of natural sounds? Are these substrates innate or shaped by learning?

Our laboratory investigates these questions in the model system of the songbird. Electrophysiological techniques are used to record neural responses from hierarchical stages of auditory processing. Theoretical methods from areas such as statistical signal processing, systems theory, probability theory, information theory and pattern recognition are applied to characterize how neurons in the brain encode natural sounds. Computational models are constructed to understand the processing of natural sounds both at the single neuron and the network level, to model neural selectivity and discrimination, and to explore the role of learning in shaping the neural code.

Current Research

• Neural Coding of Natural Sounds: Theoretical methods for characterizing auditory receptive fields, statistics of natural sounds, neural encoding and decoding, information theoretic approaches to characterizing efficiency of coding
• Hierarchical Auditory Processing: Characterizing successive stages of auditory processing and changes in neural selectivity to natural sounds
• Neural Discrimination: Quantifying neural discriminability of different classes of behaviorally relevant sounds, dynamics of discrimination
• Population Coding of Natural Sounds: Coding of natural sounds in neural populations, quantitative methods for detecting patterns of population activity, dynamics of correlation, information in patterns of population activity
• Learning in Single Neurons and Auditory Networks: Changes in receptive field structure during learning, dependence of receptive field structure on the statistics of natural sounds

Selected Recent Publications

Billimoria CP, Kraus BJ, Narayan R, Maddox RK, Sen K “Invariance and Sensitivity to Intensity in Neural Discrimination of Natural Sounds” Journal of Neuroscience 28(25): 6304-8 (2008)

Narayan R, Best V, Ozmeral E, McClaine E, Dent M, Shinn-Cunningham B, Sen K “Cortical Interference Effects in the Cocktail Party Problem” Nature Neuroscience 10: 1601-7 (2007)

Shamir M, Sen K, Colburn HS “Temporal Coding of Time-Varying Stimuli” Neural Computation 19:3239-61 (2007)

Wang L, Narayan R, Grana G, Shamir M, Sen K ” Cortical Discrimination of Complex Natural Stimuli: Can Single Neurons Match Behavior?” Journal of Neuroscience 27(3): 582–89 (2007)

Narayan R, Grana G, Sen K “Distinct Time-Scales in Cortical Discrimination of Natural Sounds in Songbirds” Journal of Neurophysiology 96: 252-258 (2006)