This seminar will be held at the Jerome L. Greene Science Center (9th floor lecture hall) on Columbia's Manhattanville campus. Columbia University's Intercampus Shuttle Service is the best way to travel between campuses.
The brain can be viewed as a probabilistic estimator, where sensory statistics bias judgments. Dr. Peña and his team addressed this question in the neural pathway supporting the owl’s sound localization. In the owl’s auditory midbrain sensory evidence on sound direction is weighted by its reliability to generate an adaptive motor command for head-orientation. This coding can emerge by convergent projections from a map of space onto premotor neurons controlling behavior. Thus, the topographic sensory representation of auditory space can be read out to adjust behavioral responses by statistics of the sensory input. These experimental results indicate that sensory statistics are both represented and anticipated in the owl’s brain, and built into premotor signals. Experimental results on human subjects yields consistent results, providing evidence towards convergent coding strategies underlying orienting responses across species.
Dr. Peña obtained MD and PhD degrees at the schools of Medicine and Science in Uruguay, and conducted postdoctoral work at Caltech under the mentorship of Mark Konishi. Research at Einstein has centered on how the brain represents sensory information, with a focus on auditory processing. He and his team have used a Neuroethological approach, motivated by the idea that specialized behaviors and brains can be informative about fundamental principles of brain function. The model system has been sound-driven head-orienting responses of barn owls, commanded by the activation of accessible populations of neurons in the auditory midbrain. They perform electrophysiology in vivo and in vitro, and complement these techniques with theoretical and behavioral approaches. They have used in vivo intracellular and cell-attached recordings to investigate combination selectivity in auditory spatial receptive fields and coincidence-detector neurons. To map spatial receptive fields in free field and manipulate context in a more naturalistic manner, they designed a high-density speaker array. The team's latest studies using multi- electrode arrays pursue the question whether sensory representation in the barn owl’s brain can be explained by probabilistic inference. This work points to the critical importance of assessing population responses to understand how behavior is commanded by the brain. Research on barn owls generated hypotheses testable in human sound localization, which have motivated experiments underway.
Dr. Peña is this seminar series' student- and postdoc-nominated speaker. His seminar will be immediately followed by a reception.
The Columbia Neuroscience Seminar series is a collaborative effort of Columbia's Zuckerman Institute, the Department of Neuroscience, the Doctoral Program in Neurobiology and Behavior and the Columbia Translational Neuroscience Initiative, and with support from the Kavli Institute for Brain Science.