The following is a summary of “Imagery adds stimulus-specific sensory evidence to perceptual detection,” published in the February 2022 issue of Ophthalmology by Dijkstra, et al.
The overlap between internally generated imagery and externally triggered perception poses a challenge for monitoring perceptual reality, as it is difficult to distinguish between sensory signals that reflect reality and those that arise from the imagination. For a study, researchers sought to investigate the interaction between these processes in determining visual experience, a study was conducted using psychophysics.
Participants were instructed to detect oriented gratings while simultaneously imagining the same grating, a perpendicular grating, or nothing.
The study’s results showed that congruent imagery caused a leftward shift of the psychometric function, which relates stimulus contrast to the perceptual threshold, compared to incongruent imagery and no imagery. The researchers proposed a model in which imagery adds sensory signals to the perceptual input, increasing the visibility of perceived stimuli. This suggested that the brain does not discount self-generated sensory signals from imagery compared to changes in sensory signals caused by self-generated movement.
The findings have important implications for understanding how the brain processes sensory information and integrate it with internally generated information. They highlighted the importance of considering the role of imagery in perception and suggested that it may play a more significant role than previously thought. Further research was needed to investigate this effect’s underlying mechanisms and its potential clinical applications.
Overall, this study contributes to understanding the complex interplay between perception and imagination and sheds light on the neural processes underlying visual experience.