Toward ecological validity in expression discrimination: Forced-choice saccadic responses to posed and naturalistic...

Area of Science:

• Psychology
• Cognitive Science
• Neuroscience

Background:

• Facial expressions, particularly those signaling emotion, capture attention and influence perception.
• Previous research often used posed facial expressions, potentially exaggerating effects.
• The efficacy of discriminating naturalistic facial expressions remains less understood.

Purpose of the Study:

• To investigate the speed and accuracy of discriminating between happy, threatening, and neutral facial expressions.
• To compare performance using posed versus naturalistic facial expression databases.
• To determine if naturalistic faces yield similar or different behavioral biases compared to posed faces.

Main Methods:

• Utilized forced-choice saccadic eye movement responses.
• Participants (N=40) performed discrimination tasks with happy/neutral and neutral/threatening face pairs.
• Compared behavioral markers between posed and naturalistic facial expression datasets.

Main Results:

• Happy expressions were rapidly distinguished from neutral expressions in both posed and naturalistic trials.
• Discrimination bias was amplified for posed expressions.
• Threatening expressions more strongly interfered with neutral expression selection in posed trials.
• Naturalistic faces, despite visual noise, led to faster and more accurate eye movements than posed faces.

Conclusions:

• Naturalistic facial expressions elicit comparable behavioral biases to posed expressions in discrimination tasks.
• Naturalistic stimuli facilitate more efficient visual processing for facial expression discrimination.
• Findings support a shift towards more ecologically valid research in social perception.