How to Improve Memory & Focus Using Science Protocols | Dr. Charan Ranganath

In Ranganath’s trivia fMRI study, the more curious participants were about an answer, the stronger the activation in dopaminergic midbrain and ventral striatum. That curiosity state not only improved memory for the trivia answer but also for unrelated faces shown in between. Practically, you can harness this by intentionally stoking curiosity (posing questions, seeking novelty, identifying knowledge gaps) before studying or learning; the elevated dopamine state makes subsequent information more likely to stick.

The prefrontal cortex doesn’t just hold information—it controls what you attend to based on goals and values. Ranganath distinguishes raw attention (what’s loud, bright, salient) from intention (choosing what matters and why). If you don’t clearly decide, “This is what I want to remember and for what purpose,” your brain defaults to salience, leading to fragmented, shallow memories. Before important experiences (lectures, meetings, family events), briefly state to yourself what you want to take away; that intentional framing recruits prefrontal control and improves encoding.

Every time you check your phone, email, or social media during a task, you incur switch costs in both directions and disrupt the continuity needed for the hippocampus to form a cohesive memory episode. You end up with many shallow fragments instead of one strong, retrievable memory trace. A practical intervention is to create strict “single-task” blocks: put your phone in another room or on a different device (e.g., a separate ‘social media phone’ with a timer), use focus modes, and commit to one activity until a defined break.

Large longitudinal data (e.g., a 29,000-person, 10-year Chinese cohort) show that people with 4–6 healthy lifestyle factors—regular exercise, good sleep, healthy diet (Mediterranean/DASH style with leafy greens, fruits, vegetables, fish; low processed foods), no smoking, minimal alcohol, cognitive engagement, and social connection—performed nearly twice as well on memory tests as those with 0–1 factor. Hearing aids, cataract treatment, and good oral hygiene also meaningfully reduce dementia risk via reduced cognitive load and inflammation. The implication: consistent, basic health habits are as powerful as any single drug we have for cognitive aging.

Untreated hearing loss forces the brain to work harder just to decode sound, diverting resources from memory and accelerating decline; hearing aid use is now linked to reduced Alzheimer’s risk. Cataracts and poor vision likewise impair cognition. Gum disease can allow oral bacteria into the bloodstream, potentially crossing the blood–brain barrier and fueling neuroinflammation, which interacts with amyloid/tau pathology. Regular audiology checks, eye exams (and cataract treatment when needed), and strong oral hygiene are low-friction, high-yield interventions for preserving cognition.