{"id":1404,"date":"2020-01-10T21:44:00","date_gmt":"2020-01-10T12:44:00","guid":{"rendered":"http:\/\/cinetjp-static3.nict.go.jp\/english\/?p=1404"},"modified":"2022-08-27T21:31:33","modified_gmt":"2022-08-27T12:31:33","slug":"20191216_4202","status":"publish","type":"event","link":"http:\/\/cinetjp-static3.nict.go.jp\/english\/event\/20191216_4202\/","title":{"rendered":"Takahiro Doi: \u201cSuboptimal visual averaging reveals compulsory, nonlinear mechanisms in human vision\u201d"},"content":{"rendered":"\n<p>January 10, 2020<br>16:00-17:00<br>CiNet 1F Conference Room<\/p>\n\n\n\n<p>Takahiro Doi<br>Department of Psychology<br>University of Pennsylvania<\/p>\n\n\n\n<p>Host:\u00a0Ichiro Fujita\u00a0(PI)<\/p>\n\n\n\n<p>Abstract:<br>How humans integrate ambiguous and conflicting signals has been a focus of perception and decision-making research for decades. Identifying the source of sub-optimality can reveal the information integration strategy used by the nervous system to solve ecologically relevant tasks in natural environments. In this study, we examined visual spatial averaging, a fundamental process underlying the transformation of noisy local signals into a more stable global estimate. A novel paradigm was used to measure the degree of human sub-optimality against the ideal observer. In this talk, first I will establish that human visual averaging is suboptimal in both luminance and stereoscopic domains: the visual system does not faithfully compute the average of a spatially varied stimulus, especially when spatial variability is large. Then, I will present a series of experiments designed to identify the source of sub-optimality. Our results indicate two kinds of nonlinear mechanisms at work: one is related to the down-weighting of outlier samples and the other is the spatial interaction among nearby signals within a stimulus. These compulsory nonlinear mechanisms, while suboptimal in our laboratory task, may reflect an information integration strategy that improves performance in more natural contexts cluttered with object boundaries and illumination variation.<\/p>\n","protected":false},"featured_media":0,"template":"","acf":[],"_links":{"self":[{"href":"http:\/\/cinetjp-static3.nict.go.jp\/english\/wp-json\/wp\/v2\/event\/1404"}],"collection":[{"href":"http:\/\/cinetjp-static3.nict.go.jp\/english\/wp-json\/wp\/v2\/event"}],"about":[{"href":"http:\/\/cinetjp-static3.nict.go.jp\/english\/wp-json\/wp\/v2\/types\/event"}],"wp:attachment":[{"href":"http:\/\/cinetjp-static3.nict.go.jp\/english\/wp-json\/wp\/v2\/media?parent=1404"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}