That of the mad scientist is a stereotype fortunately contradicted by intelligent people and in good mental health. Yet, there is something true in associating intelligence with mental illnesses. Even the big screen often proposes this combination: the famous Dr. House is an excellent doctor who nevertheless fights with a form of acute depression, or Scherlock Holmes, the intelligent investigator, clearly sociopathic.
How much is true and scientific in the connection between "madness" and intelligence?
The correlation between high IQ and increased risk of developing mental illness has assumed greater scientific value thanks to a study, which examined 3715 volunteers with an IQ above 130: the result of the research shows that those with an intelligence above the norm they are exposed to a significantly higher risk for disorders and psychological illnesses.
In particular, anxiety disorders are the most common among survey participants: about 20% of volunteers presented this type of problem, compared to a 10% incidence in a generic population sample.
At the base of this greater predisposition there is a hyper-sensitivity to external stimuli: people with a high IQ experience a greater level of awareness that leads them to react more to the stimuli of the environment. This results in an overactive nervous system
"Insignificant stimuli, such as the contact between a garment tag on the skin or an unusual sound, activate a hyper-body response that generates a level of chronic low-level stress," said Nicole Tetreault, co-author of the study.
This extreme sensitivity and hyper-excitability contribute to a higher intelligence, but can also be disabling on a certain plane.
The study, however, is limited to talking about a correlation bond and not of causality: it is therefore not certain if the exaggerated responses to the stimuli are a consequence of the intelligence or the cause. In any case, the study confirms that there really is a link between IQ and mental health.