A team of scientists from Basel University Hospital and the University of Zurich set out to explore how regular caffeine intake might influence cognitive abilities, publishing their results in Scientific Reports. Their aim was to better understand whether daily coffee consumption could have lasting effects on mental performance and brain function in healthy adults.
Many people reach for coffee to lift energy or sharpen attention, yet long-term patterns of caffeine use do not always align with those short-term boosts. Observations in the field have suggested that the everyday habit may, over time, alter how the brain handles tasks that require sustained focus and quick thinking. This study contributes to that dialogue by examining changes that occur across days of caffeine use, rather than symptoms observed in a single moment.
The research team selected twenty male participants to reduce variability in caffeine processing that can arise from hormonal differences among women. All volunteers were healthy and free from neurological disorders, and they participated in a controlled sequence of sessions designed to compare three distinct caffeine scenarios under the same experimental conditions.
In one phase, subjects consumed moderate quantities of caffeine for ten days. In another phase, caffeine was replaced with a placebo for ten days, allowing researchers to separate the effects of caffeine from expectations and other nonchemical influences. Finally, after completing the caffeine portion, participants abstained from caffeine for 36 hours following a nine-day period of intake. The order of these phases was randomized for each participant, and caffeine was administered in its pure form rather than through beverages to ensure accurate dosing.
To gauge cognitive performance, researchers administered a battery of assessments focused on concentration, psychomotor speed, and working memory. Working memory refers to the ability to hold information briefly while manipulating it to perform tasks. Throughout testing, the team tracked error rates and reaction times to quantify performance changes. In addition to behavioral measures, functional MRI scans provided a window into how caffeine might alter brain activity in relation to cognitive demands.
The study’s findings indicated that moderate daily caffeine intake could impair working memory, leading to more mistakes and slower responses on tasks that require holding and manipulating information. MRI results supported this view by showing that neural activity patterns under caffeine did not align as neatly with the cognitive processes being tested, suggesting a potential disconnect between brain signals and task performance during regular caffeine exposure. These changes appeared most evident after sustained caffeine use, rather than during brief, irregular doses.
These insights contribute to a broader conversation about how popular stimulants affect the brain over time. While caffeine remains a widely consumed substance with generally favorable short-term effects for many people, the study implies that persistent, moderate consumption may subtly shift cognitive dynamics in ways that are not immediately obvious in everyday tasks. The researchers emphasize the importance of considering duration of use and the possibility of gradual adjustments in brain functioning when evaluating caffeine’s overall impact on mental performance over days and weeks. Further investigations could help clarify whether individual sensitivity, genetic factors, or comorbid lifestyle habits modulate these effects, and whether findings translate to different populations or age groups in Canada and the United States. [citation attribution needed]
Overall, the work invites a cautious view of habitual caffeine consumption. It does not deny the short-term perceptual benefits many people experience, but it highlights that regular use might come with trade-offs for certain cognitive functions, particularly working memory. As coffee culture continues to evolve and new caffeine-delivery methods emerge, ongoing research will be essential to map out who might be most affected and how best to balance daily energy with long-term cognitive health.