Cognitive overload in students: understanding it and easing off

At exam time, I often hear the same sentence: "I read, I reread, and nothing goes in." It is not laziness or a lack of intelligence. It is often cognitive overload: the brain is taking in more than it can absorb, and it gets saturated.

I am a sophrologist, hypnotherapist and wellbeing coach in Bordeaux. I work with teenagers and students, and I have run workshops in French state schools. I have also known overload from the inside: before my burnout, working in start-ups, I spent my days juggling ten subjects and ended up remembering nothing at all.

Here you will find what cognitive overload is, why students are so prone to it, how to revise without overloading your brain, three exercises to handle exam stress and pointers on when to ask for help.

What cognitive overload is

When you learn, your brain uses its working memory: it keeps information in mind while you understand it, connect it to what you already know and store it. The problem is that it is small. Work by the researcher Nelson Cowan shows that it can only hold around three to five items at a time in a young adult.

When you ask it for more, it overflows. That is what we call cognitive overload. You reread the same line without understanding it, you forget the formula you learnt five minutes ago, you feel as if your head is full and empty at the same time.

Mental load and stress get mixed up

Stress makes things worse. Part of your attention is busy worrying: about failing, about the time left, about what your parents will think. The WHO points out that it is natural to feel stressed before exams, and that stress makes it harder to concentrate. It becomes a loop: you understand less, so you stress more, so you understand even less.

Why students are so prone to it

During your studies, everything piles up. Several very different subjects in the same day, exams bunched into a few weeks, often a part-time job, sometimes running a home on your own for the first time, money worries. On top of that, there is the phone, always within reach.

The multitasking trap

Revising with notifications on, a series playing in the background and one eye on your messages means asking your working memory to handle everything at once. A study by Ophir and colleagues at Stanford University compared people who juggle a lot between screens with people who do so less. The first group were more easily distracted and less efficient when they had to switch from one task to another. In other words, multitasking does not make you faster. It wears you out.

Warning signs

Some signs come up often in the students I see:

• you read without taking anything in, even simple things;
• it takes you much longer than before to get started on a study session;
• you forget appointments, belongings, dates;
• you struggle to fall asleep because your lectures keep going round in your head;
• you are irritable or, on the contrary, you cry more easily;
• you get headaches or stomach aches more often at exam time.

When I ask them about it, many tell me they thought they were "useless" or "not cut out for studying". That is almost never the case. Their brain was simply overloaded, and changing the way they worked and bringing the pressure down was often enough to get things moving again.

One or two of these signs for a few days is what many students go through before exams. If they settle in for weeks, or if you can no longer work at all, it is time to talk about it. I come back to this below.

Revising differently to avoid overload

The good news is that some ways of revising put much less strain on your memory than others. A large review by Dunlosky and colleagues assessed ten learning techniques. Two clearly stand out: testing yourself and spreading your revision over time. Highlighting and rereading, the two methods students use most, are among those that help least.

Test yourself rather than rereading

Close your notes and try to recall what you have just learnt: write it down from memory, answer questions, explain it out loud as if to a friend. It is more uncomfortable than rereading, because you get stuck. But that effort is exactly what makes the information stick.

Spread it out rather than cramming

It is better to go over a chapter four times for twenty minutes across two weeks than once for eighty minutes the night before. Make a simple plan, with each subject coming back at regular intervals.

One thing at a time

Phone in another room or on airplane mode. One subject, one precise goal per session ("I can redo exercises 1 to 3"), then a real break. Many of the students I work with study in blocks of 25 to 45 minutes, followed by five to ten minutes away from screens.

Sleep

Sleep is not time taken away from revision. The WHO recommends regular sleep times, limiting screens before bed and avoiding caffeine in the evening. An all-nighter before an exam often means an even smaller working memory the next day.

Three exercises to bring the pressure down

These are sophrology exercises I give students before exams. You can do them at home, in a library or just before walking into the exam room.

1. The long out-breath

Breathe in through your nose for a count of four, then breathe out slowly through your mouth for a count of six to eight, as if you were blowing on a candle without putting it out. Do this for two minutes. A long out-breath helps the body come out of alarm mode. If you want to go further, heart coherence breathing works on the same principle, five minutes three times a day.

2. Grounding through your feet

Sit with your feet flat on the floor. Bring your attention to the contact of your feet with the ground, then to the weight of your body on the chair, then to your hands resting on the table. Thirty seconds is enough. It is the ideal exercise when panic rises in the exam room: it brings you back to the present, here and now.

3. Picturing the exam going well

The night before, with your eyes closed, picture the exam in detail: you arrive, sit down, read the paper calmly and start with the question you know best. Picture a moment where you get stuck too, and see yourself breathing and then carrying on. In my sessions, I often guide this exercise with teenagers in sophrology, because it prepares the body as much as the mind.

You will find more exercises in my sophrology exercises to do at home.

On the day of the exam

A few simple pointers I give every time:

• arrive early, so you do not add the stress of the commute;
• avoid revising in the corridor with others, it often ramps up the pressure;
• before you start, take three breaths with a long out-breath;
• read the whole paper, then start with what you know how to do;
• if your mind goes blank, put your pen down, ground your feet, breathe for a minute and move on: the information often comes back once you stop chasing it.

When to ask for help

Sophrology does not replace medical advice. Talk to your doctor or your university health service if you have been sleeping very badly for weeks, if you can no longer get up or go to lectures, if you feel drained and low all the time, or if you have dark thoughts. In that last case, do not wait: talk to someone close to you or a doctor straight away. Exhaustion can affect students too, and I have described the signs to watch for in my article on the signs of burnout.

When stress is there without taking over everything, sophrology can help you regain control before an exam period. I work with teenagers and adults at my practice on rue Ducau, and I also offer online sophrology, which is handy if you study far from Bordeaux. For a very specific fear of exams, hypnosis for teenagers can also be an option, at my practice only. My background is on the about page.

In the meantime, try just one thing tonight: close your notes and recite what you have just learnt. Then two minutes of long out-breaths before you go to sleep.