The role of attention in motion extrapolation: Are moving objects 'corrected' or flashed objects attentionally delayed?

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Motion into and out of the blind spot: evidence for spatial extrapolation of moving objects

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Flash-lag chimeras: the role of perceived alignment in the composite face effect

Spatial alignment of different face halves results in a configuration that mars the recognition of the identity of either face half (). What would happen to the recognition performance for face halves that were aligned on the retina but were perceived as misaligned, or were misaligned on the retina but were perceived as aligned? We used the 'flash-lag' effect () to address these questions. We created chimeras consisting of a stationary top half-face initially aligned with a moving bottom half-face. Flash-lag chimeras were better recognized than their stationary counterparts. However when flashed face halves were presented physically ahead of moving halves thereby nulling the flash-lag effect, recognition was impaired. This counters the notion that relative movement between the two face halves per se is sufficient to explain better recognition of flash-lag chimeras. Thus, the perceived spatial alignment of face halves (despite retinal misalignment) impairs recognition, while perceived misalignment (despite retinal alignment) does not

Spontaneous Gender Categorization in Masking and Priming Studies: Key for Distinguishing Jane from John Doe but Not Madonna from Sinatra

Facial recognition is key to social interaction, however with unfamiliar faces only generic information, in the form of facial stereotypes such as gender and age is available. Therefore is generic information more prominent in unfamiliar versus familiar face processing? In order to address the question we tapped into two relatively disparate stages of face processing. At the early stages of encoding, we employed perceptual masking to reveal that only perception of unfamiliar face targets is affected by the gender of the facial masks. At the semantic end; using a priming paradigm, we found that while to-be-ignored unfamiliar faces prime lexical decisions to gender congruent stereotypic words, familiar faces do not. Our findings indicate that gender is a more salient dimension in unfamiliar relative to familiar face processing, both in early perceptual stages as well as later semantic stages of person construal

[Review] Nancy Kanwisher and John Duncan, ed. (2004) Functional neuroimaging of visual cognition: attention and performance XX

Review of: Functional neuroimaging of visual cognition: attention and performance XX. N. Kanwisher and J. Duncan (Eds.). Oxford University Press, Oxford, 2004. No. of pages 572. ISBN 0-19-852845-

What's in a name change? Visual prediction makes extrapolation real and functional

Nijhawan redraws our attention to the problem of accurately perceiving an ever-changing visual world via a sensory system that has finite and significant communication times. The quandary is compelling and stark, but the suggestion that the visual system can compensate for these transmission delays by extrapolating the present is not so unequivocal. However, in this current airing of contradictory issues, accounts, and findings, Nijhawan trades spatial extrapolation - a rather specific concept introduced earlier (in Nijhawan 1994) for visual prediction - a far more expansive notion that forces the issue of both the perceived reality and functional significance of compensation. 2008 Cambridge University Press 2008

Visual structure and the integration of form and color information

Recent evidence challenges the view that attention acts on the outputs of early filters dedicated to processing motion, color, and orientation. Instead, "proto-objects" specified by shading, depth, direction of lighting, and surface information are thought to provide input to attentional processing. These findings are extended here to the parsing of occlusion-based contours. Multicolored occlusion structures were briefly presented and illusory conjunctions measured More illusory conjunctions were made to structures in which color was inconsistent with form information, a result that can be explained by a property of the visual system that biases the integration of color to be consistent with form. Results show that this constraint was based on global structural descriptions rather than the local information provided by T-junctions and collinearity. Together, these results offer a new tool for the study of the binding problem in vision

What's in a name change? Visual prediction makes extrapolation real and functional

Nijhawan redraws our attention to the problem of accurately perceiving an ever-changing visual world via a sensory system that has finite and significant communication times. The quandary is compelling and stark, but the suggestion that the visual system can compensate for these transmission delays by extrapolating the present is not so unequivocal. However, in this current airing of contradictory issues, accounts, and findings, Nijhawan trades spatial extrapolation - a rather specific concept introduced earlier (in Nijhawan 1994) for visual prediction - a far more expansive notion that forces the issue of both the perceived reality and functional significance of compensation. 2008 Cambridge University Press 2008

Priming of faces from one half to the other.

No description supplie

Simon Sees as Simon Does: Evidence for a Perception-Action Model of Letter Recognition.

Simon Sees as Simon Does: Evidence for a Perception-Action Model of Letter Recognition Parkinson, Jim and Khurana, Beena (2006) Simon Sees as Simon Does: Evidence for a Perception-Action Model of Letter Recognition. In: 10th annual meeting of the Association for the Scientific Study of Consciousness, 23-26 June 2006, Oxford, UK. Full text available as: PDF - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader 688 Kb Alternative URL: http://www.sussex.ac.uk/users/jmp30 Abstract Simon Sees as Simon Does: Evidence for a Perception-Action Model of Letter Recognition Does the perception of objects that are the result of human actions reflect the dynamic structure of the actions that give rise to them? Previously (ASSC9), we showed that stroke order primes letter recognition: Computer generated letters, e.g., `N¿, are presented as a temporally unfolding sequence of constituent strokes. Letter recognition is faster if the stroke sequence mimics writing action compared to when it does not. We proposed that stroke order priming is due to letter perception reflecting the temporal structure of letter production. Here we manipulate the availability of the strokes via masking and reduced exposure durations in order to test the non-strategic nature of stroke order priming. In Experiment 1 each frame in a stroke sequence was presented for 100 ms interspersed with 100 ms pattern masks. Stroke order priming occurred even in the presence of masking. In two further experiments, each frame was presented without masking for durations ranging from 10-500 ms. A significant stroke order priming effect occurred even at 20 ms per stroke. Moreover, we also observed a `garden path¿ effect, in that an initial stroke order consistent with letter writing slowed responses to a subsequent non-letter. This replication of stroke order priming across a large range of frame durations attests to the robustness of the effect. The magnitude of the priming effect, in relation to frame-duration, appears to be normally distributed; reduced priming at both lower and higher frame-durations with a peak priming effect at frame-durations of around 100 ms. Intriguingly, the frame-durations that render peak priming are consonant with average writing speed in terms of time-per-stroke (Plamondon, 1991). The modulation of stroke order priming by frame-duration suggests that priming may have both visual and motoric contributors. In sum, the masking and frame-duration findings endorse a perception-action model of letter recognition, even in the absence of the dynamic information associated with handwritten letters. Priming in the presence of visual masks and greatly reduced exposure intervals further questions the tenability of a strategic account of stroke order priming. Peak priming with frame durations that match writing speed suggests that Simon sees as Simon does