O. Scott Gwinn

O. Scott Gwinn

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Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2010 in Perception
Verified
Journal Article
Closed access
KBKevin R. Brooks
Kevin R. Brooks
OGO. Scott Gwinn
O. Scott Gwinn
Faces of individuals with African and European heritage (henceforth referred to as Black and White respectively) feature two major differences: those of skin tone and morphological characteristics. Although considerations of perceived race are important to various psychological subdisciplines, to date the relative influence of morphological versus photometric characteristics has not been investigated. We attempted to influence the perceived racial typicality of a central target face by manipulating perceived skin tone using the well-known lightness contrast illusion. As expected, ratings of skin tone were influenced by surround faces, yet ratings of perceived racial typicality were not, suggesting a dissociation between the two judgments. Surprisingly, skin tone contributes little to perceived race, leaving facial morphology as the dominant cue. These results may shed light on failures to find effects of racial typicality in studies of prejudice where judgments were based on photographs with altered skin tone alone.

19 May 2020 in Social Cognitive and Affective Neuroscience
Verified
Journal Article
Open access
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DSDerek C Swe
Derek C Swe
RPRomina Palermo
Romina Palermo
OGO. Scott Gwinn
O. Scott Gwinn
GRGillian Rhodes
Gillian Rhodes
MNMarkus Neumann
Markus Neumann
CSClare A M Sutherland
Clare A M Sutherland
Trustworthiness is assumed to be processed implicitly from faces, despite the fact that the overwhelming majority of research has only involved explicit trustworthiness judgements. To answer the question whether or not trustworthiness processing can be implicit, we apply an electroencephalography fast periodic visual stimulation (FPVS) paradigm, where electrophysiological cortical activity is triggered in synchrony with facial trustworthiness cues, without explicit judgements. Face images were presented at 6 Hz, with facial trustworthiness varying at 1 Hz. Significant responses at 1 Hz were observed, indicating that differences in the trustworthiness of the faces were reflected in the neural signature. These responses were significantly reduced for inverted faces, suggesting that the results are associated with higher order face processing. The neural responses were reliable, and correlated with explicit trustworthiness judgements, suggesting that the technique is capable of picking up on stable individual differences in trustworthiness processing. By demonstrating neural activity associated with implicit trustworthiness judgements, our results contribute to resolving a key theoretical debate. Moreover, our data show that FPVS is a valuable tool to examine face processing at the individual level, with potential application in pre-verbal and clinical populations who struggle with verbalization, understanding or memory.

27 June 2019 in Scientific Reports
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Journal Article
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DCDaniel J. Carragher
Daniel J. Carragher
NTNicole A. Thomas
Nicole A. Thomas
OGO. Scott Gwinn
O. Scott Gwinn
MNMike E. R. Nicholls
Mike E. R. Nicholls
“The cheerleader effect” refers to the increase in attractiveness that an individual face experiences when seen in a group of other faces. It has been proposed that the cheerleader effect occurs because (a) the visual system rapidly summarises a group of faces into an ensemble representation, (b) which is hypothesised to be highly attractive because of its average facial characteristics, and (c) observers remember individual faces to be more alike the ensemble representation than they were, due to hierarchical structure of visual working memory. Across three experiments, we investigated whether the cheerleader effect is consistent with hierarchical encoding, by asking observers to give attractiveness ratings to the same target faces shown in groups and alone. Consistent with hierarchical encoding, the largest attractiveness increases of 1.5–2.0% occurred when target faces were presented in groups of faces that could be mentally summarised to create an ensemble representation with average facial characteristics. Surprisingly, smaller cheerleader effects still occurred in conditions that were incompatible with hierarchical encoding (i.e., groups with non-human images). Together, these results offer only limited evidence for the role of hierarchical encoding in the cheerleader effect, suggesting that alternative mechanisms must be explored in future research.

28 May 2015 in Visual Cognition
Verified
Journal Article
Closed access
OGO. Scott Gwinn
O. Scott Gwinn
KBKevin R. Brooks
Kevin R. Brooks
In the current study we use contingent face aftereffects to examine the contributions made by morphology and facial luminance cues to the encoding of race. African and European facial images differed in both morphology and luminance (ML), in morphology alone (M), or in luminance alone (L). Significant aftereffects were found in conditions where test stimuli included morphological information (ML and M), but not when it was absent (L). Furthermore, the size of the aftereffect for test conditions specifying race using both cues (ML) was no greater than when morphological information was the sole cue (M). This suggests that the effects measured here can be accounted for by differences in morphology alone. These results indicate that not only are individual reports of perceived racial typicality more significantly influenced by morphological shape cues than surface cues, but morphological cues appear to form the basis of the underlying neural encoding for faces of different races.

27 April 2021 in Laterality
Verified
Journal Article
Closed access
ACAndrea Ciricugno
Andrea Ciricugno
MBMegan L. Bartlett
Megan L. Bartlett
OGO. Scott Gwinn
O. Scott Gwinn
DCDaniel J. Carragher
Daniel J. Carragher
MNMichael E.R. Nicholls
Michael E.R. Nicholls
Healthy individuals typically show a leftward attentional bias in the allocation of spatial attention along the horizontal plane, a phenomenon known as pseudoneglect, which relies on a right hemispheric dominance for visuospatial processing. Also, healthy individuals tend to overestimate the upper hemispace when orienting attention along the vertical plane, a phenomenon that may depend on asymmetric ventral and dorsal visual streams activation. Previous research has demonstrated that when attentional resources are reduced due to increased cognitive load, pseudoneglect is attenuated (or even reversed), due to decreased right-hemispheric activations. Critically, whether and how the reduction of attentional resources under load modulates vertical spatial asymmetries has not been addressed before. We asked participants to perform a line bisection task both with and without the addition of a concurrent auditory working memory task with lines oriented either horizontally or vertically. Results showed that increasing cognitive load reduced the typical leftward/upward bias with no difference between orientations. Our data suggest that the degree of cognitive load affects spatial attention not only in the horizontal but also in the vertical plane. Lastly, the similar effect of load on horizontal and vertical judgements suggests these biases may be related to only partially independent mechanisms.

1 August 2013 in Journal of Vision
Verified
Journal Article
Open access
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OGO. Scott Gwinn
O. Scott Gwinn
KBKevin R. Brooks
Kevin R. Brooks
Opposing aftereffects can be simultaneously induced by adapting to faces of different races distorted in opposite directions, allowing researchers to infer that faces are encoded against race-specific prototypes. This effect also suggests the existence of dissociable pools of neurons sensitive to race, each of which has been differently adapted to cause an opposite aftereffect. More recent studies have suggested that changes in the strength of race-contingent aftereffects reveal evidence of categorical perception, as they are larger when the adapting faces straddle the racial category boundary. We examined whether changes in these effects more closely correspond to a dichotomous categorical judgment, reflecting highly race-selective neural mechanisms, or more continuous perceptions of racial typicality, reflecting visual channels that are more broadly tuned. In Experiment 1, faces with a range of “morph levels” (i.e., relative contributions of Asian/Caucasian faces) were either rated on a continuous scale for Asian/Caucasian typicality, or simply categorized as Asian/Caucasian. As expected, typicality ratings showed a shallow slope (observers were sensitive to morph level over a broad range), while dichotomous racial categorization showed a steep slope (a rapid switch from categorization as Asian-Caucasian). In Experiment 2, race-contingent adaptation was assessed using test faces with various morph levels. Aftereffect size showed a shallow slope, closely resembling the racial typicality ratings, but showing a significant difference to the categorization data. This suggests that although the visual channels processing these faces do show some selectivity to race, they are sensitive to perceptions of racial typicality, showing a gradual transition of activity across a broad range of faces along the racial continuum.