Categorical Perception of Fear and Anger Expressions in Whole, Masked and Composite Faces.

Human observers are remarkably proficient at recognizing expressions of emotions and at readily grouping them into distinct categories. When morphing one facial expression into another, the linear changes in low-level features are insufficient to describe the changes in perception, which instead fol...

Full description

Bibliographic Details
Main Authors: Martin Wegrzyn, Isabelle Bruckhaus, Johanna Kissler
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2015-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC4532458?pdf=render
_version_ 1818581771808145408
author Martin Wegrzyn
Isabelle Bruckhaus
Johanna Kissler
author_facet Martin Wegrzyn
Isabelle Bruckhaus
Johanna Kissler
author_sort Martin Wegrzyn
collection DOAJ
description Human observers are remarkably proficient at recognizing expressions of emotions and at readily grouping them into distinct categories. When morphing one facial expression into another, the linear changes in low-level features are insufficient to describe the changes in perception, which instead follow an s-shaped function. Important questions are, whether there are single diagnostic regions in the face that drive categorical perception for certain parings of emotion expressions, and how information in those regions interacts when presented together. We report results from two experiments with morphed fear-anger expressions, where (a) half of the face was masked or (b) composite faces made up of different expressions were presented. When isolated upper and lower halves of faces were shown, the eyes were found to be almost as diagnostic as the whole face, with the response function showing a steep category boundary. In contrast, the mouth allowed for a substantially lesser amount of accuracy and responses followed a much flatter psychometric function. When a composite face consisting of mismatched upper and lower halves was used and observers were instructed to exclusively judge either the expression of mouth or eyes, the to-be-ignored part always influenced perception of the target region. In line with experiment 1, the eye region exerted a much stronger influence on mouth judgements than vice versa. Again, categorical perception was significantly more pronounced for upper halves of faces. The present study shows that identification of fear and anger in morphed faces relies heavily on information from the upper half of the face, most likely the eye region. Categorical perception is possible when only the upper face half is present, but compromised when only the lower part is shown. Moreover, observers tend to integrate all available features of a face, even when trying to focus on only one part.
first_indexed 2024-12-16T07:38:48Z
format Article
id doaj.art-b58013473ac64f76a2e1674415ee7a0e
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-12-16T07:38:48Z
publishDate 2015-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-b58013473ac64f76a2e1674415ee7a0e2022-12-21T22:39:09ZengPublic Library of Science (PLoS)PLoS ONE1932-62032015-01-01108e013479010.1371/journal.pone.0134790Categorical Perception of Fear and Anger Expressions in Whole, Masked and Composite Faces.Martin WegrzynIsabelle BruckhausJohanna KisslerHuman observers are remarkably proficient at recognizing expressions of emotions and at readily grouping them into distinct categories. When morphing one facial expression into another, the linear changes in low-level features are insufficient to describe the changes in perception, which instead follow an s-shaped function. Important questions are, whether there are single diagnostic regions in the face that drive categorical perception for certain parings of emotion expressions, and how information in those regions interacts when presented together. We report results from two experiments with morphed fear-anger expressions, where (a) half of the face was masked or (b) composite faces made up of different expressions were presented. When isolated upper and lower halves of faces were shown, the eyes were found to be almost as diagnostic as the whole face, with the response function showing a steep category boundary. In contrast, the mouth allowed for a substantially lesser amount of accuracy and responses followed a much flatter psychometric function. When a composite face consisting of mismatched upper and lower halves was used and observers were instructed to exclusively judge either the expression of mouth or eyes, the to-be-ignored part always influenced perception of the target region. In line with experiment 1, the eye region exerted a much stronger influence on mouth judgements than vice versa. Again, categorical perception was significantly more pronounced for upper halves of faces. The present study shows that identification of fear and anger in morphed faces relies heavily on information from the upper half of the face, most likely the eye region. Categorical perception is possible when only the upper face half is present, but compromised when only the lower part is shown. Moreover, observers tend to integrate all available features of a face, even when trying to focus on only one part.http://europepmc.org/articles/PMC4532458?pdf=render
spellingShingle Martin Wegrzyn
Isabelle Bruckhaus
Johanna Kissler
Categorical Perception of Fear and Anger Expressions in Whole, Masked and Composite Faces.
PLoS ONE
title Categorical Perception of Fear and Anger Expressions in Whole, Masked and Composite Faces.
title_full Categorical Perception of Fear and Anger Expressions in Whole, Masked and Composite Faces.
title_fullStr Categorical Perception of Fear and Anger Expressions in Whole, Masked and Composite Faces.
title_full_unstemmed Categorical Perception of Fear and Anger Expressions in Whole, Masked and Composite Faces.
title_short Categorical Perception of Fear and Anger Expressions in Whole, Masked and Composite Faces.
title_sort categorical perception of fear and anger expressions in whole masked and composite faces
url http://europepmc.org/articles/PMC4532458?pdf=render
work_keys_str_mv AT martinwegrzyn categoricalperceptionoffearandangerexpressionsinwholemaskedandcompositefaces
AT isabellebruckhaus categoricalperceptionoffearandangerexpressionsinwholemaskedandcompositefaces
AT johannakissler categoricalperceptionoffearandangerexpressionsinwholemaskedandcompositefaces