Inhibition, impulses and the nonsense we do – 10/23/2023 – Luciano Melo

It happened in a supermarket: a man very maliciously groped a woman. The two did not know each other. It then became the epicenter of a commotion that took over the shelves and boxes. It took a long, long time before it was discovered that the man was not a shameless harasser, but a sick person. The violent act was the first undisguised sign of brain cancer, precisely in the prefrontal cortex, previously undiagnosed.

The prefrontal cortex is a large nerve center. Connected to many other brain regions, it makes up a vast network of influences. These connections organize our interactions with the world, their activities are transformed into plans and coping with unforeseen events. This core is essential for us to persist or give up, as it calibrates the internal pressures of our volitions and inhibitions.

Inhibition emerged in scientific texts to represent the mechanism by which the intellect controls passions and overcomes impulses. In 1649, Descartes wrote: ”…if anger makes the hand rise in order to attack, the will can normally restrain it; If fear incites the legs to flee, willfulness can stop them.” This concept is tied to the morals of classical philosophy, well summarized in the words of Franz Gall (1758-1828), the controversial pioneer in saying what each part is for of the brain: “the laws of nature decree that the faculties of a lower order must obey those of a higher order.” Embryonic neuroscientific ideas suggest that agency and consciousness produce inhibition. Therefore, to exercise inhibitory controls, self-awareness is necessary.

But, in fact, all it takes is one neuron. These cells often inhibit the activity of their peer or other bodily targets. Therefore, a singular structure, long before morality was invented, had already initiated inhibition in some of our ancestors. More macroscopically, several brain areas interrupt the functions of others. The main expressions of this process are cognitive inhibition and behavioral inhibition.

Cognitive inhibition is our ability to resist distraction, whether it be a salience in the environment or an inappropriate or irrelevant thought. It is in our midst to suppress interference, at the cost of much or minimal intentional effort. And at other times it is unconscious, as our brain involuntarily filters what will be sucked into memory. Behavioral inhibition controls impulses that violate the rule of the moment and prepares us for changes in the environment.

Thanks to my clear explanations, you, dear and rational reader, already know how a brain tumor corrupts neural containment mechanisms. With this extra repertoire, at a party you will have the option of nudging the friend next to you to tell her that a problem in the prefrontal cortex can suppress the ability to interrupt inappropriate thoughts, which will result in uncontrollable cravings, which will ultimately be expressed in a violent act. Your friend will agree and add that violence can arise from excessive impulsiveness, when frontal failure no longer guarantees contingencies.

Unfortunately, both may be wrong. I warn the ladies that what I did was light a match against an entire cave. Be careful, neuroscience is limited and decodes the brain into generalizations. Outside of laboratories, the mental state remains largely inaccessible. Other explanations for what happened in the supermarket are welcome and perhaps more accurate.

The loss of mental control also causes impulsivity, a predisposition to quick and poorly planned reactions in response to stimuli, without weighing the negative consequences of these reactions. But remember: aggression is often a deliberate and controlled act. It is possible that the man in the supermarket lost his ability to judge and optimistically assessed that the woman would accept him. In this situation, the neoplasm caused the brain to inhibit the effect of information from the environment and its memory, which would alert it to the genesis of crooked reasoning.

Strange? Nothing. This happens all the time, even in normal brains. Take his example, my persevering reader and smoker. When burning a cigarette, you distort risks. Dominated by an optimistic bias, it underestimates harm and overestimates some immediate positive effects.

Inside our skull, volition and inhibition dance, and our behavior follows which dancer predominates. Without impulses, we would fall into apathy. On the other hand, without inhibitions, we would not correct our thoughts and actions. This ballet of our neurons seems wonderful. But we only need to read the news or look out the window to realize that it is not necessary to have a brain tumor for us to do stupid things. From the human movements of destruction comes evidence that this balance did not work.

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