Perceptual bias in Gestalt grouping by proximity affected by visual working memory load

Area of Science:

• Cognitive Psychology
• Neuroscience
• Visual Perception

Background:

• Perceptual grouping processes are susceptible to biases, such as cardinal orientation bias.
• This bias can interfere with Gestalt grouping principles like proximity in visual tasks.
• Previous research suggested visual working memory (VWM) load influences orientation bias, but confounded VWM load with perceptual complexity.

Purpose of the Study:

• To investigate whether perceptual orientation bias originates from perceptual encoding or top-down influences via VWM.
• To disentangle the effects of VWM load and perceptual load on orientation bias.
• To determine if psychophysical models of bias generalize to perceptual bias.

Main Methods:

• A simplified experimental design was employed to independently manipulate VWM load and perceptual load.
• VWM load was varied using an N-back task.
• Perceptual load was manipulated through flanker congruency in dot-lattice stimuli.

Main Results:

• The intrusion of perceptual bias into grouping by proximity was found to be dependent on VWM load.
• Perceptual load did not significantly affect the intrusion of perceptual bias.
• A dissociation was observed between perceptual orientation bias and psychophysical orientation bias.

Conclusions:

• The findings suggest that top-down effects, specifically VWM load, play a crucial role in perceptual orientation bias.
• Psychophysical models may not fully capture perceptual bias due to the significant influence of VWM.
• Future research should consider VWM's role in understanding biases in visual perception.