scholarly journals Title: Suppression durations for facial expressions under breaking continuous flash suppression: effects of faces’ low-level image properties.

2020 ◽  
Author(s):  
Abigail Webb ◽  
Paul Hibbard
Keyword(s):  
Spatial Frequency ◽  
Facial Expressions ◽  
Combined Effects ◽  
Frequency Content ◽  
Limited Evidence ◽  
Continuous Flash Suppression ◽  
Low Level ◽  
Facial Stimuli ◽  
Suppression Effects

Perceptual biases for fearful facial expressions are observed across many studies. According to the low-level, visual-based account of these biases, fear expressions are advantaged in some way due to their image properties, such as low spatial frequency content. Breaking continuous flash suppression (b-CFS) has explored these effects, and demonstrated similar biases for detecting fearful facial expressions. However, there is a degree of empirical disagreement regarding the range of spatial frequency content. Recent findings from a b-CFS study highlight the role of high, rather than low spatial frequency content in determining faces’ visibility. The present study contributes to ongoing discussions regarding the efficacy of b-CFS, and shows that the visibility of facial expressions varies according to how faces are normalised for physical contrast and spatially filtered. Findings show limited evidence of a bias for detecting fearful facial expressions, but importantly, they show that such biases are less likely to occur when faces are normalised for apparent, perceived contrast, compared to physical contrast. Together these findings further the current understanding of the combined effects of spatial frequency and contrast on face visibility under b-CFS, and raise important questions regarding procedures used to standardise facial stimuli.

scholarly journals Suppression durations for facial expressions under breaking continuous flash suppression: effects of faces’ low-level image properties

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Abigail L. M. Webb ◽  
Paul B. Hibbard
Keyword(s):  
Spatial Frequency ◽  
Facial Expressions ◽  
High Frequency ◽  
Frequency Content ◽  
Apparent Contrast ◽  
Continuous Flash Suppression ◽  
Low Level ◽  
Frequency Information ◽  
Suppression Effects

Abstract Perceptual biases for fearful facial expressions are observed across many studies. According to the low-level, visual-based account of these biases, fear expressions are advantaged in some way due to their image properties, such as low spatial frequency content. However, there is a degree of empirical disagreement regarding the range of spatial frequency information responsible for perceptual biases. Breaking continuous flash suppression (b. CFS) has explored these effects, showing similar biases for detecting fearful facial expressions. Recent findings from a b. CFS study highlight the role of high, rather than low spatial frequency content in determining faces’ visibility. The present study contributes to ongoing discussions regarding the efficacy of b. CFS, and shows that the visibility of facial expressions vary according to how they are normalised for physical contrast and spatially filtered. Findings show that physical contrast normalisation facilitates fear’s detectability under b. CFS more than when normalised for apparent contrast, and that this effect is most pronounced when faces are high frequency filtered. Moreover, normalising faces’ perceived contrast does not guarantee equality between expressions’ visibility under b. CFS. Findings have important implications for the use of contrast normalisation, particularly regarding the extent to which contrast normalisation facilitates fear bias effects.

scholarly journals Processing of Fear and Anger Facial Expressions: The Role of Spatial Frequency

2013 ◽  
Vol 4 ◽  
Author(s):  
William E. Comfort ◽  
Meng Wang ◽  
Christopher P. Benton ◽  
Yossi Zana
Keyword(s):  
Spatial Frequency ◽  
Facial Expressions

scholarly journals Saccadic eye movements are deployed faster for salient facial stimuli, but are relatively indifferent to their emotional content

2021 ◽  
Author(s):  
Abigail Webb ◽  
Jordi M Asher ◽  
Paul Hibbard
Keyword(s):  
Spatial Frequency ◽  
Response Times ◽  
Saccadic Eye Movements ◽  
Threat Bias ◽  
Facial Stimuli ◽  
Facial Information ◽  
Naturally Occurring ◽  
Socially Relevant ◽  
Saccadic Responses

The present study explores the threat bias for fearful facial expressions using saccadic latency as the response mode, with a particular focus on the role of low-level facial information, including spatial frequency, physical contrast, and apparent, perceived contrast. In a simple localisation task, participants were presented with spatially-filtered versions of neutral, fearful, angry and happy faces. Faces were either composed of naturally-occurring, expression-related differences in contrast, normalised for RMS contrast, or normalised for their apparent, perceived contrast. Together, findings show that saccadic responses are not biased toward fearful expressions compared to neutral, angry or happy counterparts, regardless of their spatial frequency content. Saccadic response times are, however, significantly influenced by the physical contrast of facial stimuli, and the extent to which these are preserved or normalised at the physical (RMS matched) and psychophysical (perceptually matched) level. We discuss the implications of findings for the threat bias literature, and the extent to which image processing can be expected to influence behavioural responses to socially-relevant facial stimuli.

Interocular Grouping of Visual Attributes during Binocular Rivalry

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 304-304
Author(s):  
T V Papathomas ◽  
I Kovács ◽  
A Feher
Keyword(s):  
Spatial Frequency ◽  
Binocular Rivalry ◽  
The Other ◽  
National Academy Of Sciences ◽  
Low Level ◽  
Visual Attributes ◽  
Competition Hypothesis ◽  
Academy Of Sciences

The need to revise the eye competition hypothesis of binocular rivalry, and to include the role of stimulus competition has been demonstrated recently by Kovács, Papathomas, Feher, and Yang (1996 Proceedings of the National Academy of Sciences of the USA93 15508 – 15511) and Logothetis, Leopold, and Sheinberg [1996 Nature (London)380 621 – 624]. Kovács et al showed that observers can obtain one-colour percepts when presented with chromatically rivalrous stimuli, even when there are targets of two different colours in each eye. In this study we investigate whether other attributes, in addition to colour, can drive interocular grouping, and how they interact. We extended the ‘patchwork’ rivalrous stimuli (Kovács et al) to study how colour, orientation, spatial frequency, and motion can group interocularly, and how they interact in grouping. Gabor patches are used, because they allow conjunctions of attributes to be formed systematically. To study the ability of an attribute (or a combination of attributes) to group interocularly, we induce rivalry by virtue of interocular differences in that attribute (or combination), and keep the other attributes fixed in both eyes' images. The main advantage of these stimuli is that they enable us to decorrelate the effects of eye competition and percept competition in binocular rivalry. The data show that colour is the most powerful attribute in grouping, and that combinations are stronger than single attributes. Overall, the results indicate that similarity in low-level attributes can drive interocular grouping, and that binocular rivalry follows complex rules of perceptual organisation that cannot be accounted for by eye suppression alone.

scholarly journals The Role of Spatial Frequencies for Facial Pain Categorization

2021 ◽  
Author(s):  
Isabelle Charbonneau ◽  
Joël Guérette ◽  
Stéphanie Cormier ◽  
Caroline Blais ◽  
Guillaume Lalonde-Beaudoin ◽  
...  
Keyword(s):  
Spatial Frequency ◽  
Visual Information ◽  
Facial Pain ◽  
A Priori ◽  
Data Driven ◽  
Low Level ◽  
Spatial Frequencies ◽  
Pain Recognition ◽  
Practical Implications

Abstract Studies on low-level visual information underlying pain categorization have led to inconsistent findings. Some are showing an advantage for low spatial frequency information (SFs) and others a preponderance of mid SFs. This study aims to clarify this gap in knowledge since these results have different theoretical and practical implications, such as how far away an observer can be in order to categorize pain. This study addresses this question by using two complementary methods: a data-driven method without a priori about the most useful SFs for pain recognition and a more ecological method that simulates the distance of stimuli presentation. We reveal a broad range of important SF for pain recognition starting from low to relatively high SFs and showed that performance is optimal in a short to medium distance (1.2 to 4.8 meters) but declines significantly when mid SFs are no longer available. This study reconciles previous results that show an advantage of LSFs over HSFs when using arbitrary cutoffs, but above all reveal the prominent role of mid-SFs for pain recognition across two experimental tasks.

scholarly journals Battle of the Mondrians: Investigating the Role of Unpredictability in Continuous Flash Suppression

i-Perception ◽  
2018 ◽  
Vol 9 (4) ◽  
pp. 204166951879293 ◽  
Author(s):  
Shui’Er Han ◽  
David Alais ◽  
Randolph Blake
Keyword(s):  
Spatial Pattern ◽  
Spatial Uncertainty ◽  
Continuous Flash Suppression ◽  
Low Level ◽  
Low Pass ◽  
Temporal Predictability ◽  
Static Target ◽  
Temporal Sequences ◽  
Modest Effect

In continuous flash suppression (CFS), a dynamic sequence of Mondrian patterns presented to one eye suppresses a static target in the other eye for several seconds at a time. Its effectiveness has been linked to low-level properties such as spatial frequency and orientation, but the role of higher order influences remains unstudied. Here, using a tracking paradigm, we asked if the spatial and temporal predictability of the Mondrian sequence affects CFS dynamics. Predictable temporal sequences were regularly updated every 100 ms or modulated sinusoidally in pixel luminance at 2 Hz. Unpredictable temporal sequences were irregularly updated or had stochastic pixel luminance changes across time. To vary spatial predictability, sequences were either updated with different Mondrian patterns or had a fixed spatial pattern. We found a modest effect of spatial uncertainty when the target modulation was low (0.125 Hz) but not temporal uncertainty, which had no significant effects regardless of target modulation. Similar results were obtained when we pitted the standard Mondrian sequence against sequences with a fixed spatial pattern and temporally low-pass filtered sequences in a binocular rivalry paradigm. Thus, not only was the effect of information predictability was modest and spatial, but it was also dependent on the presence of higher temporal frequencies. Together, the results demonstrate the significance of low-level properties in affecting CFS dynamics and the possible involvement of pattern structure masking in CFS.

The role of spatial frequency information in the decoding of facial expressions of pain

Pain ◽  
2017 ◽  
Vol 158 (11) ◽  
pp. 2233-2242 ◽  
Author(s):  
Shan Wang ◽  
Christopher Eccleston ◽  
Edmund Keogh
Keyword(s):  
Spatial Frequency ◽  
Facial Expressions ◽  
Frequency Information

Metacontrast Masking and Attention

1999 ◽  
Vol 10 (6) ◽  
pp. 508-515 ◽  
Author(s):  
John Shelley-Tremblay ◽  
Arien Mack
Keyword(s):  
Spatial Frequency ◽  
Strong Influence ◽  
Early Vision ◽  
Happy Face ◽  
Metacontrast Masking ◽  
Low Level ◽  
Own Name ◽  
Meaningful Stimuli

Metacontrast masking is generally considered an effect of preattentive processes operative in early vision. Because of the growing evidence of the role of attention in other phenomena previously considered low level and preattentive, its possible role in masking was explored in three experiments in which meaningful target stimuli known to capture attention (one's own name or a happy-face icon) were compared with control stimuli identical in spatial frequency and luminance. Not only were these salient stimuli significantly more resistant to masking than the control stimuli, but when one of the meaningful stimuli served as a mask, its strength was increased relative to a less meaningful variant, documenting the strong influence of attention on masking.

scholarly journals Unconscious processing of facial dominance: The role of low-level factors in access to awareness

2018 ◽  
Author(s):  
Timo Stein ◽  
Deema Awad ◽  
Surya Gayet ◽  
Marius Peelen
Keyword(s):  
Social Characteristics ◽  
Physical Stimulus ◽  
Social Emotional ◽  
Unconscious Processing ◽  
Continuous Flash Suppression ◽  
Low Level ◽  
Parsimonious Explanation ◽  
Preferential Access ◽  
Eye Region

Visual stimuli with social-emotional relevance have been claimed to gain preferential access to awareness. For example, recent studies used the breaking continuous flash suppression paradigm (b-CFS) to show that faces that are perceived as less dominant and more trustworthy are prioritized in awareness. Here we asked whether these effects truly reflect differences in social-emotional meaning or whether they can be equally explained by differences in low-level stimulus properties. In Experiment 1, we successfully replicated dominance- and untrustworthiness-related slowing for upright faces. However, these effects were equally strong for inverted faces, even though it was more difficult to perceive social characteristics in inverted faces. The previously reported correlation between dominance- and untrustworthiness-related slowing in b-CFS and self-reported propensity to trust did not replicate. Experiment 2 showed that dominance-related slowing in b-CFS can also be observed when only presenting the eye region of faces, and even when the eye region was presented inverted and/or with reversed contrast polarity, in which case personality traits were no longer discernible. These results were replicated in Experiment 3 following a pre-registration protocol. Altogether, our findings link dominance-related slowing in b-CFS to physical differences in the eye region that are – when presented in isolation – unrelated to the perception of dominance. We conclude that low-level physical stimulus differences provide a parsimonious explanation for the effect of social facial characteristics on access to awareness.

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