You can spot plenty of students staying overnight in libraries during exam season. It might look impressive.
But, research shows that the human brain is not designed for prolonged study sessions, and the ability to learn and remember new information quickly declines with time, usually far before students stop studying.
What is learning?
Learning is simply establishing new connections in our brains.
Through repeated activation, connections between neurons are strengthened. This process is known as Long-Term Potentiation (LTP)— the mechanism behind synaptic plasticity.
However, learning does not happen instantly. Firstly, new information is stored in working memory, which has limited capacity. If this information is processed sufficiently, it is then transferred to long-term memory.
The transfer depends on memory consolidation, a process that describes how newly acquired information is turned into a long-lasting form. The most important fact about working memory is that it is limited. An overload of new information stops the learning.
Why can’t we constantly learn things for hours on end?
The simple answer— the brain has strict biological limits.
Working memory is limited and cannot store many items at the same time. Once the limit is exceeded, new information cannot be stored, which is explained by the Cognitive Load Theory.
Long hours of studying can only lead to cognitive and neural fatigue. Continuous stimulation of neurons becomes less efficient over time as the chemical messengers required for signalling become depleted.
The brain consumes about 20% of the body’s energy. High-intensity focus depletes glucose and leads to a buildup of adenosine, which makes the brain “sluggish.”
Learning also requires periods of rest so that the brain can stabilise and organise new information. That is why breaks are equally important as focused learning.
This limit not only exists in theory, but is observed in real life. In a study of elite musicians, the best violinists practised an average of 24 hours per week, which is roughly 3.5 hours per day of highly focused, deliberate practice.
It is important to note that these tendencies are also observed in other fields which require intense deliberate practice to achieve strong results. As deliberate practice is cognitively demanding, even experts rarely sustain more than a few hours of intense focus per day.
How should we study then?
Since the brain operates with strict limits, we should keep them in mind.
Short, focused study sessions are more efficient than long, continuous ones. 25-50 minute sessions are the “sweet spot” for maintaining high focus.
Breaks are incredibly important as they allow neural systems to recover and restore efficiency.
Spaced study sessions are also something to consider as they improve retention.
Finally, sleep is very important. During sleep, the brain consolidates new information and filters out useless information.
Conclusion
All-night grinding in the library may seem productive, but it could in fact be more detrimental than you think. Our brains are not designed to learn for many hours; they need breaks and sleep to consolidate all the learned material.
Understanding those limits allows us to plan our studying more efficiently and achieve better results in shorter periods of time.
