Thinking hard can leave you feeling exhausted. The feeling is known as ‘cognitive fatigue,’ and it typically kicks in after extended bouts of concentration. It is not a sign that you are about to pass out from exhaustion or anything like that. Instead, it is a natural response to your brain working harder than usual.
When we think hard, exercise our brain and challenge ourselves with complex tasks, we tend to feel sleepy soon after. Why does this happen? Is it a sign of overexertion? It is because thinking hard uses energy, and that energy needs time to replenish before you feel alert again. But why does this happen? Let’s take a look at some explanations.
Why thinking hard will make you tired
We all know that thinking is a taxing mental activity. But this does not mean it is too demanding for the brain to handle. Many studies have shown that our brains can take quite a bit of mental work before we start feeling tired.
The average human brain contains about 86 billion neurons connected by an estimated 100 trillion synapses – the connections between neurons. Each neuron can communicate with thousands of other neurons and receive signals from billions of other neurons via the synapses. That makes the number of possible connections in the brain enormous so you would expect that thinking hard on anything will result in a lot of neuronal activity.
The problem occurs when we think about something too complex for our brains to cope with. When this happens, our brains try to reduce their workload by shutting down some processes and slowing down other processes to cope with the strain. The result is cognitive fatigue – a state in which we feel tired even if we do not exert ourselves physically or mentally.
Understanding Metabolites
Before gaining control over your brain, it is excellent first to understand glutamate. It is a metabolite, meaning this is something your body produces during the conversion of food to energy. However, know that it is the biggest neurotransmitter in the brain. It implies the metabolite is an essential messenger to your brain cells.
Simple research was conducted in Paris as researchers wanted to understand how cognitive fatigue works. During the study, participants were assigned various tasks to complete. They also had to make economic choices after the functions. Researchers then examined the participant’s metabolites using MRS (magnetic resonance spectroscopy).
They found that participants who handled more cognitively demanding tasks had a glutamate buildup in their lateral prefrontal cortex (LPFC). Most practitioners believe this part of your brain is crucial and may perform problem-solving, planning, and inhibition tasks. Experts claim that once the glutamate accumulates in the brain, your LPFC may require extra energy to activate.
Working Smarter
With the above study trying to understand why you feel tired after thinking hard, the big question is, how can you go around it?
The founder of Menlo Park Psychiatry & Sleep Medicine, Dr. Alex Dimitriu, says people need to stock how they feel. You ought to determine what causes the fatigue. Is it anxiety, lack of sleep, or being too busy at work?
Experts claim that glutamate concentrations will often reduce when you sleep. Dr. Alex mentioned that enough sleep is the ideal way to deal with cognitive fatigue.
The Pacific Neuroscience Institute senior research scientist Jennifer Bramen says that avoiding multi-tasking can help reduce cognitive fatigue. If you focus on only one activity at a time, you will prevent brain fatigue. The expert says she takes some minutes of mental break between different tasks.
You could also change the physical surroundings during your breaks. Walk outside, stroll the street, stand by the window, or do something outside the working area. Most experts recommend you take breaks in between tasks and even get some exercise. That way, no glutamate will accumulate in your brain for thinking hard.