Limits...
Absence of Sex-Contingent Gaze Direction Aftereffects Suggests a Limit to Contingencies in Face Aftereffects.

Kloth N, Rhodes G, Schweinberger SR - Front Psychol (2015)

Bottom Line: To alleviate this concern, one would need to demonstrate some limit to contingent aftereffects.We found that adaptation induced pronounced gaze direction aftereffects, i.e., participants were biased to perceive small gaze deviations to both the left and right as direct.Importantly, however, aftereffects were identical for male and female test faces, showing that the contingency of face sex and gaze direction participants experienced during the adaptation procedure had no effect.

View Article: PubMed Central - PubMed

Affiliation: Australian Research Council Centre of Excellence in Cognition and its Disorders, School of Psychology, The University of Western Australia , Perth, WA, Australia ; DFG Research Unit Person Perception, Friedrich Schiller University of Jena , Jena, Germany.

ABSTRACT
Face aftereffects (e.g., expression aftereffects) can be simultaneously induced in opposite directions for different face categories (e.g., male and female faces). Such aftereffects are typically interpreted as indicating that distinct neural populations code the categories on which adaptation is contingent, e.g., male and female faces. Moreover, they suggest that these distinct populations selectively respond to variations in the secondary stimulus dimension, e.g., emotional expression. However, contingent aftereffects have now been reported for so many different combinations of face characteristics, that one might question this interpretation. Instead, the selectivity might be generated during the adaptation procedure, for instance as a result of associative learning, and not indicate pre-existing response selectivity in the face perception system. To alleviate this concern, one would need to demonstrate some limit to contingent aftereffects. Here, we report a clear limit, showing that gaze direction aftereffects are not contingent on face sex. We tested 36 young Caucasian adults in a gaze adaptation paradigm. We initially established their ability to discriminate the gaze direction of male and female test faces in a pre-adaptation phase. Afterwards, half of the participants adapted to female faces looking left and male faces looking right, and half adapted to the reverse pairing. We established the effects of this adaptation on the perception of gaze direction in subsequently presented male and female test faces. We found that adaptation induced pronounced gaze direction aftereffects, i.e., participants were biased to perceive small gaze deviations to both the left and right as direct. Importantly, however, aftereffects were identical for male and female test faces, showing that the contingency of face sex and gaze direction participants experienced during the adaptation procedure had no effect.

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Contingency scores. (A) Contingency scores for participants who adapted to male faces with left gaze and female faces with right gaze. (B) Contingency scores for participants who adapted to male faces with right gaze and female faces with left gaze. Error bars indicate 95% confidence intervals.
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Figure 5: Contingency scores. (A) Contingency scores for participants who adapted to male faces with left gaze and female faces with right gaze. (B) Contingency scores for participants who adapted to male faces with right gaze and female faces with left gaze. Error bars indicate 95% confidence intervals.

Mentions: Critically, the absence of a significant three-way interaction in the above analysis cannot be taken as conclusive evidence against contingency. In a final step, therefore, we calculated contingency scores for test stimuli with averted gaze, separately for participants in the two adaptation conditions based on the predicted contingency pattern. For participants who had adapted to male faces with leftward gaze and female faces with rightward gaze, one would predict a selective increase in “direct” classifications relative to baseline only for male faces with 5° and 10° leftward gaze, but not for female faces with 5° and 10° leftward gaze. Conversely, one would predict a selective increase in “direct” classifications only for female faces with 5° and 10° rightward gaze, but not for male faces with 5° and 10° rightward gaze. For participants in this adaptation condition, contingency scores for the leftward gaze conditions were therefore calculated by subtracting the increase in direct responses made to female faces with leftward gaze after adaptation relative to baseline (i.e., the unpredicted aftereffect scores for female faces) from the increase in direct responses made to male faces with leftward gaze after adaptation relative to baseline (i.e., the predicted aftereffect scores for male faces). Conversely, contingency scores for the rightward gaze conditions were calculated by subtracting the unpredicted increase in direct classifications made to male faces with rightward gaze from the predicted increase in direct classifications made to female faces with rightward gaze. For participants who had adapted to male faces with rightward gaze and female faces with leftward gaze, contingency scores were calculated accordingly. Positive contingency scores therefore indicate a contingent aftereffect pattern, with larger aftereffects for test faces of the same sex as the adaptors looking in the same direction compared to opposite-sex faces, contingency scores around 0 would indicate the absence of such contingencies, i.e., similar aftereffects for test faces of both sexes. Importantly, and confirming the above analyses, contingency scores were close to 0, and 95% confidence intervals included 0 in all conditions (Figure 5). One-sample t-tests confirmed that contingency scores were not significantly different from 0 for any gaze direction in either adaptation condition (all ts < 1.5, all ps > 0.18).


Absence of Sex-Contingent Gaze Direction Aftereffects Suggests a Limit to Contingencies in Face Aftereffects.

Kloth N, Rhodes G, Schweinberger SR - Front Psychol (2015)

Contingency scores. (A) Contingency scores for participants who adapted to male faces with left gaze and female faces with right gaze. (B) Contingency scores for participants who adapted to male faces with right gaze and female faces with left gaze. Error bars indicate 95% confidence intervals.
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Related In: Results  -  Collection

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Figure 5: Contingency scores. (A) Contingency scores for participants who adapted to male faces with left gaze and female faces with right gaze. (B) Contingency scores for participants who adapted to male faces with right gaze and female faces with left gaze. Error bars indicate 95% confidence intervals.
Mentions: Critically, the absence of a significant three-way interaction in the above analysis cannot be taken as conclusive evidence against contingency. In a final step, therefore, we calculated contingency scores for test stimuli with averted gaze, separately for participants in the two adaptation conditions based on the predicted contingency pattern. For participants who had adapted to male faces with leftward gaze and female faces with rightward gaze, one would predict a selective increase in “direct” classifications relative to baseline only for male faces with 5° and 10° leftward gaze, but not for female faces with 5° and 10° leftward gaze. Conversely, one would predict a selective increase in “direct” classifications only for female faces with 5° and 10° rightward gaze, but not for male faces with 5° and 10° rightward gaze. For participants in this adaptation condition, contingency scores for the leftward gaze conditions were therefore calculated by subtracting the increase in direct responses made to female faces with leftward gaze after adaptation relative to baseline (i.e., the unpredicted aftereffect scores for female faces) from the increase in direct responses made to male faces with leftward gaze after adaptation relative to baseline (i.e., the predicted aftereffect scores for male faces). Conversely, contingency scores for the rightward gaze conditions were calculated by subtracting the unpredicted increase in direct classifications made to male faces with rightward gaze from the predicted increase in direct classifications made to female faces with rightward gaze. For participants who had adapted to male faces with rightward gaze and female faces with leftward gaze, contingency scores were calculated accordingly. Positive contingency scores therefore indicate a contingent aftereffect pattern, with larger aftereffects for test faces of the same sex as the adaptors looking in the same direction compared to opposite-sex faces, contingency scores around 0 would indicate the absence of such contingencies, i.e., similar aftereffects for test faces of both sexes. Importantly, and confirming the above analyses, contingency scores were close to 0, and 95% confidence intervals included 0 in all conditions (Figure 5). One-sample t-tests confirmed that contingency scores were not significantly different from 0 for any gaze direction in either adaptation condition (all ts < 1.5, all ps > 0.18).

Bottom Line: To alleviate this concern, one would need to demonstrate some limit to contingent aftereffects.We found that adaptation induced pronounced gaze direction aftereffects, i.e., participants were biased to perceive small gaze deviations to both the left and right as direct.Importantly, however, aftereffects were identical for male and female test faces, showing that the contingency of face sex and gaze direction participants experienced during the adaptation procedure had no effect.

View Article: PubMed Central - PubMed

Affiliation: Australian Research Council Centre of Excellence in Cognition and its Disorders, School of Psychology, The University of Western Australia , Perth, WA, Australia ; DFG Research Unit Person Perception, Friedrich Schiller University of Jena , Jena, Germany.

ABSTRACT
Face aftereffects (e.g., expression aftereffects) can be simultaneously induced in opposite directions for different face categories (e.g., male and female faces). Such aftereffects are typically interpreted as indicating that distinct neural populations code the categories on which adaptation is contingent, e.g., male and female faces. Moreover, they suggest that these distinct populations selectively respond to variations in the secondary stimulus dimension, e.g., emotional expression. However, contingent aftereffects have now been reported for so many different combinations of face characteristics, that one might question this interpretation. Instead, the selectivity might be generated during the adaptation procedure, for instance as a result of associative learning, and not indicate pre-existing response selectivity in the face perception system. To alleviate this concern, one would need to demonstrate some limit to contingent aftereffects. Here, we report a clear limit, showing that gaze direction aftereffects are not contingent on face sex. We tested 36 young Caucasian adults in a gaze adaptation paradigm. We initially established their ability to discriminate the gaze direction of male and female test faces in a pre-adaptation phase. Afterwards, half of the participants adapted to female faces looking left and male faces looking right, and half adapted to the reverse pairing. We established the effects of this adaptation on the perception of gaze direction in subsequently presented male and female test faces. We found that adaptation induced pronounced gaze direction aftereffects, i.e., participants were biased to perceive small gaze deviations to both the left and right as direct. Importantly, however, aftereffects were identical for male and female test faces, showing that the contingency of face sex and gaze direction participants experienced during the adaptation procedure had no effect.

No MeSH data available.


Related in: MedlinePlus