New research published in Nature Communications suggests that the part of the brain responsible for visual processing plays a more significant role in working memory than previously understood. Traditionally, it was believed that working memory relied heavily on the prefrontal cortex. However, findings indicate that multiple brain regions are involved.
Clayton Curtis, a psychology professor at New York University and senior author of the paper, stated, “Our results show that working memory isn’t confined to one specific brain area, but is instead distributed across multiple regions—from the prefrontal cortex in the front to early visual cortex, which situated at the back and helps us see.” This discovery could lead to new clinical research avenues for neurological and psychiatric conditions with working-memory impairments.
Curtis highlighted potential implications for schizophrenia treatments, which currently focus on the prefrontal cortex despite perceptual issues experienced by patients. He also noted that visual aspects of working memory are sensitive to changes in brain dysfunction and could help assess Alzheimer’s disease progression and treatment responses.
The study’s lead author, Mrugank Dake, an NYU doctoral student, explored whether the early visual cortex (V1) is essential not only for vision but also for memory. Previous studies showed V1 activity correlates with visual working memory but did not confirm its necessity.
Curtis explained that studying people blind from V1 damage was not feasible as they couldn’t see information to memorize. Instead, researchers used transcranial magnetic stimulation (TMS) to disrupt neural activity in V1 while participants stored visual information in working memory. The magnetic pulses targeted a localized part of V1 representing a specific visual field area.
Results revealed impaired memory when TMS affected parts of the visual field corresponding to V1 disruption. This impairment occurred even when TMS was applied after images disappeared from view, suggesting V1 actively holds information for future use.
“This suggests that V1 is not merely used for seeing but is also used to actively hold onto that information for future use,” Curtis said. Dake added, “We discovered that disrupting neural activity in V1 affects visual working memory—a surprising finding given its assumed role as only a basic processor of visual information.”
The research received support from National Institutes of Health grants R01-EY016407 and R01-EY033925.
