Guest Lecture - Eye movements probe the temporal resolution of multisensory integration

by Dr. Miriam Spering, Dept. of Ophthalmology & Visual Sciences, University of British Columbia, Vancouver, Canada

will take place on Thursday, April 20th, 2023 from 15:00 to 16:00 hours in CBBM Building, Ground Floor, Seminar Room Levi-Montalcini.

Host: Prof. Jonas Obleser
Institute of Psychology I, University of Lübeck

Abstract: Seeing and perceiving the visual world is an active and multimodal process during which the eyes continuously scan the visual environment to sample information. My research group uses human eye movements as sensitive indicators of perception and performance in naturalistic tasks such as catching prey or hitting a ball. These tasks require prediction of an object’s trajectory from a brief glance at its motion, and an ultrafast decision about whether, when and where to intercept. In the real world, tasks like this rely on both vision and hearing. Here, I will present results from two research programs that use continuous eye movements as a readout of the brain processes underlying the integration of information across the senses. The first series of studies investigates go/no-go decisions in a simulated baseball environment, combining visual and auditory batting cues. Even though auditory cues were not informative, observers’ interceptive actions were biased by sound. Continuous eye movements uncovered that sound affected interception within 125 milliseconds of visual target onset, suggesting that auditory and visual signals are combined earlier than previously thought. The second set of studies uses an ultra-rapid orienting task, relying on observers’ ability to orient and inhibit eye movements in response to sudden-onset distractors. Combining visual and auditory distractors revealed an additive response mode at latencies as short as 100 milliseconds. These studies demonstrate that eye movements are an excellent model system that reveals the time course, computations, and brain mechanisms underlying multisensory integration.