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European Conference on Visual Perception 2017 Abstract Book Welcome Address Contents The 40th European Conference on Visual Perception (ECVP) Welcome Address 1 took place in Berlin (Germany), from August 27th to 31st, 2017. With about 1200 fellow vision scientists coming to the Monday August 28th Poster presentations 2 Hauptstadt, this has been the biggest ECVP yet. As organiz- ers of this meeting, we were impressed by the large number Monday August 28th Oral presentations 63 of contributions that allowed us to put together an amaz- Monday August 28th Symposia presentations 73 ing program. In three parallel tracks and across four days, we hosted over 200 talks in 12 symposia and 24 talk ses- Tuesday August 29th Poster presentations 78 sions, and more than 750 posters in 7 poster sessions. We also consider ourselves lucky that we could win Nava Ru- Tuesday August 29th Oral presentations 138 bin and Shin’ya Nishida for inspiring Perception and Rank Prize lectures, respectively. In addition, we used the oppor- Tuesday August 29th Symposia presentations 146 tunity to create a new format that we hope will catch on in the years to come — the Keynote Dialogue, in which two speak- Wednesday August 30th Poster presentations 151 ers present their opposing views on a fundamental question Wednesday August 30th Oral presentations 212 in vision science. This year, we enjoyed a stimulating and entertaining session in which Brian Scholl and Merav Ahissar Wednesday August 30th Symposia presentations 220 discussed the question “Does cognition penetrate percep- tion?” Thursday August 31st Poster presentations 225 In this abstract book, you will find the summary of each of Thursday August 31st Oral presentations 254 these contributions. We hope that the ECVP 2017 in Berlin stays with you for a long time. We certainly keep a fond Thursday August 31st Symposia presentations 262 memory of this meeting. Author Index 267 The organizing team: Niko Busch, Guido Hesselmann, Mar- ianne Maertens, Florian Ostendorf, Martin Rolfs, & Philipp Sterzer. Monday August 28th Poster presentations 2 Monday August 28th Poster presentations rates and the perceptual bias as a function of prime identity and load level. Results: Increase of visual working memory Pupil dilation during perception of the Necker load significantly reduced the perceptual ‘front-side-down’ cube reflects the viewing-from-above bias interpretation bias of the Necker cube. We further observed a tendency for fewer Necker cube reversals with higher mem- Fumiaki Sato1, Bruno Laeng2, Shigeki Nakauchi1 & Tetsuto ory load. Discussion: Our perceptual system deduces causes Minami3 in the world that produce the sensory signals by matching the sensory evidence with memory contents from previous 1Toyohashi University of Technology; 2University of Oslo; 3Toyohashi University of Technology / Electronics-Inspired Interdisciplinary perceptual experiences. The perceptual result will then be Research Institute biased to the most probable solution(s). We hypothesize, that when working memory is loaded, its contribution to the ‘Necker Cube’ is a well known bistable figure. Previous stud- resolution of the ambiguity is reduced and thus the percep- ies showed that downward viewing is preferred than upward tual orientation bias is reduced. viewing (viewing-from-above bias). Although such a bias has been examined with psychophysical experiments, its neural basis still remains unclear. The neurocognitive aspects of Direct comparison of eye patch and virtual bistable perception could be clarified by use of pupillom- occlusion during computer-aided treatment of etry, since this measure can index the intensity of cogni- amblyopia in children tive processing, attention, and noradrenergic activity in the 1 1 brain. Specifically, this study investigated pupillary changes Svetlana Rychkova , Maria Gracheva , Roman Sandimirov & 1 while participants viewed a ‘Necker cube’ stimulus, which was Andrey Bolshakov made of corners that could be either dark or bright. When 1Institute for Information Transmission Problems (Kharkevich participants attended to surface that consisted of dark dots, Institute) Russian Academy of Sciences (IITP RAS) it was expected that pupils dilated than when attending to a surface that consisted white dots. Moreover, the perceived Some recent investigations evidenced that, in treating am- direction was manipulated by cueing one surface of the cube blyopia, virtual occlusion (VO) could have significant advan- (by temporarily filling the surface with white before the clas- tages over traditional occlusion with eye patches (PO). How- sic stimulus presentation). From the key press of participants ever, the data available are mostly obtained in adults and it was clear that the onset appearance of the Necker cube still seem to be preliminary but not comprehensive. In or- changed significantly due to the effect of the cue. As in pre- der to compare the effectiveness of using PO and VO in vious studies, the likelihood of the downward appearance children directly, we employed PO in some training sessions appeared to be stronger than the appearance of an upward and VO (realized by means of 3D technique) in others. The cube. However, the effects of the corners’ luminance on the same sets of visual stimuli and identical training procedures pupil diameter were small and non-significant. Since trials were used in the courses of treating amblyopia (10 sessions with the upward cue resulted in greater pupil diameter di- by 5 minutes) in two groups of children aged 7-14 years. lation than the downward cue, we surmise that the upward The groups had 15/15 and 15/14 patients with disbinocu- perspective requires more attentional effort than the down- lar/refractive amblyopia and similar characteristics as con- ward perspective, consistent with the view-from-above as- cerned distributions of age and initial visual acuity. The first sumption in perception of bistable figures. group underwent treatment with PO sessions then VO ses- sions (PO/VO), the second one – in inverse order (VO/PO). For the amblyopic eyes designed to treatment, the training pro- Visual working memory load reduces the cedures PO/VO and VO/PO produced increase in visual acu- perceptual orientation bias of the Necker cube ity 35%/20% and 38%/10%, respectively. In the case of VO, significant improvement in visual acuity was also registered Monika Intaite1, Miguel Castelo-Branco1, Sven P. Heinrich2, in the paired eyes (by 25%/11% after first/second course), Michael Bach2 & Jürgen Kornmeier3 while in the case of PO, visual acuity in these eyes remained 1University of Coimbra; 2Eye Center, University of Freiburg; unchanged. In addition, employment of VO results in signif- 3Department of Psychiatry and Psychotherapy, Medical Center, icant increase of binocular visual acuity (by 33%/12% after University of Freiburg, Germany first/second course). Supported by the Program III.3 of DNIT Russ Acad Sci, 2017. Introduction: During observation of the ambiguous Necker cube our perception becomes unstable and alternates spon- taneously between ‘front-side-down’ and ‘front-side-up’ 3D- interpretations, with typically longer stability durations for Investigating binocular oculomotor learning in ‘front-side-down’ (orientation bias). We studied the influ- adults with impaired stereopsis by means of ence of working memory load on perceptual dynamics of the stereoscopic stimulation and eye-tracking Necker cube. Methods: In two different experiments partic- Mariann Hudák1 & János Geier2 ipants first memorized either cubic objects (Exp. 1) or Chi- 1 2 nese characters (Exp. 2) as memory primes for 3 seconds. Pázmány Péter Catholic University; Stereo Vision Ltd Easy, medium and hard memory load conditions differed in the number of memory primes. After the memory task par- We investigate whether binocular fusion in strabismic ticipants observed a Necker cube for 15 seconds and indi- stereoanomalous adults can be restored, if the positions of cated perceptual reversals. Finally, we presented a mem- binocular stimuli are adjusted to their individual gaze po- ory probe and participants indicated whether this probe had sitions, by providing the optimal image disparity for each been present in the memory primes. We analyzed reversal person, using a stereoscope combined with an eye-tracking Monday August 28th Poster presentations 3 system. We suppose that in this case, binocular fusion and Mapping of interocular filter suppression stereopsis occurs with less effort. This visual experience is Akash S. Chima, Monika A. Formankiewicz & Sarah J. Waugh expected to aid oculomotor learning: once the 3D scene is perceived, it can serve as a cue to keep the necessary con- Anglia Ruskin University vergence, as normal image disparity is approached gradu- ally by adjusting the positions of the binocular stimuli dur- Neutral density (ND) filters placed before one eye can quan- ing the perceptual and oculomotor training. As a first step tify depth of interocular or amblyopic suppression. We inves- for this aim, the binocular fixation patterns of strabismic tigate properties of interocular filter suppression across the stereoanomalous and normal observers were investigated. central 24 deg visual field in binocularly normal adults. Sup- When stimulating only one eye, the unstimulated eye of nor- pression is quantified with luminance-defined and contrast- mal observers perfectly followed the fixations of the stimu- defined stimuli as the latter have previously revealed deeper lated eye, governed by the
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