The upper-hemifield advantage for masked face processing: Not just an attentional bias.

Area of Science:

• Cognitive Neuroscience
• Visual Perception

Background:

• Evidence suggests enhanced face processing in the upper visual field (UVF) compared to the lower visual field (LVF).
• The role of visuospatial attention in this UVF advantage remains unclear.

Purpose of the Study:

• To investigate whether an upward bias in visuospatial attention explains the enhanced face processing in the UVF.
• To determine if spatial attention modulates face processing in both UVF and LVF.

Main Methods:

• Participants performed a face sex classification task with masked primes in either UVF or LVF.
• Spatial attention was manipulated by varying the predictability of target location across sessions (50:50 UVF:LVF vs. 20:80 UVF:LVF).
• Event-related potentials (ERPs) were analyzed to assess priming effects and their timing.

Main Results:

• When target location was unpredictable, faster priming occurred for UVF faces (165 ms) than LVF faces (195 ms).
• When targets were more likely in the LVF, this advantage reversed, with faster priming for LVF faces (53 ms) than UVF faces (165 ms).
• UVF prime processing remained consistent regardless of attentional deployment.

Conclusions:

• Voluntarily directed spatial attention can modulate masked face processing in the LVF.
• Spatial attention alone does not account for the observed UVF advantage in masked face processing.
• The UVF advantage for face processing may involve mechanisms beyond attentional deployment.