Duje Tadin

Associate Professor, Department of Brain and Cognitive Sciences, Center for Visual Science, Department of Ophthalmology, University Of Rochester, NY, USA

Duje Tadin is the 2014 winner of the Elsevier/VSS Young Investigator Award. Trained at Vanderbilt, Duje Tadin was awarded the PhD. in Psychology in 2004 under the supervision of Joe Lappin. After 3 years of post-doctoral work in Randolph Blake’s lab, he took up a position at the University of Rochester, where he is currently an associate professor. Duje’s broad research goal is to elucidate neural mechanisms that lead to human visual experience. He seeks converging experimental evidence from a range of methods, including human psychophysics, computational modeling, transcranial magnetic stimulation (TMS), neuroimaging, research on special populations, collaborations on primate neurophysiology, and adaptive optics to control retinal images. Duje is probably best known for his elegant and illuminating research on spatial mechanisms of visual motion perception – work that has had a lasting impact on the field. He developed a new method to quantify motion perception using brief, ecologically relevant time scales, and then used it to discover a functionally important phenomenon of spatial suppression: larger motion patterns are paradoxically more difficult to see. Duje’s results revealed joint influences of spatial integration and segmentation mechanisms, showing that the balance between these two competing mechanisms is not fixed but varies with visibility, with spatial summation giving way to spatial suppression as visibility increases. He has also made significant contributions to several high-profile papers dealing with binocular rivalry, rapid visual adaptation, multi-sensory interactions, and visual function in individuals with low-vision and children with autism.

Elsevier/Vision Research Article

Suppressive neural mechanisms: from perception
to intelligence

Monday, May 19, 12:30 pm, Talk Room 2

Perception operates on an immense amount of incoming information that greatly exceeds brain’s processing capacity. Because of this fundamental limitation, our perceptual efficiency is constrained by the ability to suppress irrelevant information. Here, I will present a series of studies
investigating suppressive mechanisms in visual motion processing, namely perceptual suppression of large, background-like motions. We find that these suppressive mechanisms are adaptive, operating only when the sensory input is sufficiently strong to guarantee visibility. Utilizing a range of methods, we link these behavioral results with inhibitory center-surround receptive fields, such as those in cortical area MT.

What are functional roles of spatial suppression? Spatial suppression is weaker in old age and schizophrenia—as evident by paradoxically better-than-normal performance in some conditions. Moreover, these subjects also exhibit deficits in figure-ground segregation, suggesting a functional
connection. In recent studies, we report direct experimental evidence for a functional link between spatial suppression and figure-ground segregation.

Finally, I will argue that the ability to suppress information is a fundamental neural process that applies not only to perception but also to cognition in general. Supporting this argument, we find that individual differences in spatial suppression of motion signals strongly predict individual variations in WAIS IQ scores (r = 0.71).