CAREER: Perceptual and Neural Analysis of Biological Motion

University Of California-Irvine, Irvine CA

Investigators

Abstract

Humans are remarkably adept at recognizing the actions of others, even based on movement patterns alone. This ability is most dramatically shown by "point-light biological motion" animations, in which just a few dots are visible, placed at joints or other critical places. It is often easy to recognize which action is being performed, what the actor's emotional state is, and even who the person is. Although we know this information is available, little is known as to how it is perceived. This is particularly interesting because visual motion and form cues are assumed to be processed in parallel and independent streams, yet these two types of information have to be combined for point-light displays to be meaningful. Neuroimaging studies in humans have further linked biological motion perception to a regions of the brain called the superior temporal sulcus, which seems to be involved in many complex processes including social perception. With the support of the National Science Foundation, Dr. Emily Grossman at the University of California Irvine will investigate the perceptual means for the recognition of biological motion, and the brain systems involved. The perception tests will use a novel behavioral technique in which perceivers make yes/no decisions about biological motion animations viewed on a computer screen. The brain work will use functional Magnetic Resonance Imaging (fMRI) to test specific hypotheses of the combination of form and motion cues in biological motion perception. These experiments will also measure the tuning properties of brain regions supporting biological motion perception, something that has already been achieved in monkeys but not yet in humans. Theories of biological motion draw from a number of scientific domains, including research in visual perception, social perception, action understanding and motor imitation (the "mirror neuron" system). Results from the present project will influence thinking in all of these domains. The work in this proposal also involves hands-on research experience for undergraduate and graduate students, including the design and analysis of neuroimaging studies. Because UC Irvine and Dr. Grossman's laboratory both have a historical record of recruiting an ethnically diverse student population, these projects provide the opportunity to promote science among under-represented minorities. Finally, as part of the pedagogical activities in this CAREER proposal, this project will support the development of a new Neuroimaging Laboratory course in which students are trained in the practical skills necessary for brain imaging data analysis, a skill highly desirable in the upcoming cohort of cognitive neuroscientists.