Abstract

Translating noisy sensory signals to perceptual decisions is critical for successful interactions in complex environments.

Learning is known to improve perceptual judgments by filtering external noise and task-irrelevant information.

Yet, little is known about the brain mechanisms that mediate learning-dependent suppression.

Here, we employ ultra-high field magnetic resonance spectroscopy of GABA to test whether suppressive processing in decision-related and visual areas facilitates perceptual judgments during training.

We demonstrate that parietal GABA relates to suppression of task-irrelevant information, while learning-dependent changes in visual GABA relate to enhanced performance in target detection and feature discrimination tasks.

Combining GABA measurements with functional brain connectivity demonstrates that training on a target detection task involves local connectivity and disinhibition of visual cortex, while training on a feature discrimination task involves inter-cortical interactions that relate to suppressive visual processing.

Our findings provide evidence that learning optimizes perceptual decisions through suppressive interactions in decision-related networks.

Citations

Polytimi Frangou, Uzay E. Emir, Vasilis M. Karlaftis, Caroline Nettekoven, Emily L. Hinson, Stephanie Larcombe, Holly Bridge, Charlotte J. Stagg & Zoe Kourtzi . Learning to optimize perceptual decisions through suppressive interactions in the human brain. Nature Communications Jan 2019.

Sponsorship: Supported by the NIHR (E.L.H)

URI: https://www.oxfordhealth.nhs.uk/orka/title/learning-to-optimize-perceptual-decisions-through-suppressive-interactions-in-the-human-brain/