Read about the latest research published in Psychological Science:
Eran Eldar, Yael Niv, and Jonathan D. Cohen
How is the balance between focus and breadth determined during perceptual processing? The authors hypothesized that this balance is determined by neural gain such that high gain leads to perceptual processing being dominated by the most salient signal (focus), whereas low gain results in weak and strong inputs producing more equal neural activity (breadth). The researchers investigated the effects of gain on perception in a neural-network model and in an experiment in which they examined how the impact of subliminal manipulations of feature saliency on perception varied with gain. The results of these two studies supported the researchers’ hypothesis and implicate gain as a possible mechanism underlying individual differences in perception.
Georgie Powell, Zoe Meredith, Rebecca McMillin, and Tom C. A. Freeman
Bayesian models assume that cognition and perception are the product of optimal combinations of noisy input and prior knowledge. Perceptual differences, then, are influenced both by a person’s sensitivity to incoming sensory information and by their prior knowledge. It has been suggested that people with autism have a flatter prior knowledge distribution than those without autism. The researchers tested this in two studies by examining the Aubert-Fleischel phenomenon (in which perception of speed is lowered during pursuit eye movements) and by examining contrast effect and associated discrimination thresholds. The researchers found that these perceptual phenomena were predicted when differences in thresholds and autistic traits were combined in a quantitative Bayesian model. These findings highlight the importance of accounting for both prior knowledge and sensitivity to sensory inputs when explaining individual differences in perception.