Research shows that today's actions affect your brain two weeks later, especially in terms of attention, memory and cognitive function

A research team from Aalto University in Finland announced that 'the effects of daily activities such as exercising and staying up late can last up to two weeks on the brain.'

Longitudinal single-subject neuroimaging study reveals effects of daily environmental, physiological, and lifestyle factors on functional brain connectivity | PLOS Biology

https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3002797

Your Brain Changes Based on What You Did Two Weeks Ago - Newsweek
https://www.newsweek.com/brain-changes-neuroscience-exercise-sleep-health-two-weeks-1965107

Although the human brain and behavior are intimately linked, most studies to date have only examined the state of the brain at a specific moment in time, leaving it unclear how the brain responds to long-term changes in the environment or behavior.

The research team used smartphones and wearable devices to track the subjects' behavior for 133 days, and also performed 30 fMRI scans during the period to investigate how changes in the environment and behavior affect the brain over time scales ranging from days to months.

According to the paper, various behaviors such as sleep, exercise, and watching movies affect the brain, and the effects last for up to 15 days. In other words, the current brain is shaped by one's actions over the past 15 days, and the research team says, 'To better understand the brain, we need to recognize its interdependence with external factors.'

The researchers classified the brain's response to behavior into two patterns: short waves, which last less than a week, and long waves, which last between one week and 15 days. A typical example of a short wave is a rapid response, such as a decrease in concentration the day after lack of sleep, while long waves have a more gradual and lasting effect.

'It's crucial to consistently maintain good healthy habits, such as sleep, exercise and stress management,' said lead author Ana Triana. 'These habits have a particular impact on attention, memory and cognitive function, so don't just focus on the most important weeks - make sure you also focus on the weeks leading up to them.'