Use Your Eyes to See How Hard Your Brain WorksYour pupils reveal your cognitive effort in real-time.

From the show

Practical Body Science

Discover that your eyes offer a window into your mind's workload. Pupil size isn't just about light; it's a reliable biomarker for mental effort, directly linked to arousal systems in the brain. The harder your brain works, the wider your pupils get. This pupillary response is controlled by your autonomic nervous system, essentially giving you a built-in, biological effort meter. What your eyes show is a direct reflection of the cognitive load you're experiencing.