Despite its moniker, mental illness often has a biological component. Some researchers suspect it has to do with a person's inability to shut out stimuli. Selectively ignoring certain incoming sights, sounds and thoughts is a hallmark of the mentally healthy, a trait psychologists call "latent inhibition." For example, a study of nearly 200,000 20-year-old Finnish males found those with higher intelligence were more than 12 times more likely to develop bipolar disorder as they aged. The link, surmised researchers, was the capability to rapidly process information while problem-solving, a hyper-alertness thought to accompany some types of mental illnesses [source: Collingwood]. Turns out, the selective hearing your child or spouse develops when it is time to take out the trash may be a good thing.
On the other hand, biology could be behind a person's propensity for certain mental maladies. For example, researchers have discovered nerve cells in a portion of the brain called the posterior cingulate cortex become more active when monkeys explore potentially rewarding new courses of behavior instead of the normal routines. It is suspected that for people who have an obsessive-compulsive disorder compelling them to adhere to strict behavioral patterns, the flexibility to pursue new -- even potentially gratifying -- avenues is absent [source: Futurity].
And then there are those who defy their diseases. Although Tesla exhibited behaviors consistent with obsessive-compulsive disorder, his thought process was agile. Just as engineers now use computer models to construct a complicated apparatus, Tesla virtually tested and recalibrated every invention before ever building a single prototype. Only he did it entirely in his own mind!
Tesla's autobiography, in which he described his creative process, reveals that across hundreds of inventions, he never built a device that didn't work as he thought it would [source: Knapp]. The link between intelligence and mental illness -- even if we don't fully understand it -- often seems to be two sides of the same coin.
Author's Note: Is there a link between intelligence and mental illness?
When I began researching this article, I wondered how many of the world's historical geniuses would be considered mentally ill were they alive today? Turns out, probably many of them. From the suspected autism of Michelangelo, bipolar tendencies of Sylvia Path and depression of Abraham Lincoln, there are plenty of suppositions to be made. In the end, what I really found interesting was the connection between mental illness and intellect at either end of the spectrum. Both a high IQ and a low IQ are thought to protect against some forms of mental illness -- and potentially cause mental illness, too.
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- Bayne, John. "7 'Eccentric' Geniuses Who Were Clearly Just Insane." Aug. 18, 2008. (Feb. 1, 2013) Cracked. http://www.cracked.com/article_16559_7-eccentric-geniuses-who-were-clearly-just-insane_p2.html
- Collingwood, Jane. "Intelligence Linked to Bipolar Disorder." 2010. (Feb. 1, 2013) Psych Central. http://psychcentral.com/lib/2010/intelligence-linked-to-bipolar-disorder/
- Davis, Jeanie Lerche. "Did Michelangelo Have Autism?" May 26, 2004. (Feb. 1, 2013) WebMD. http://www.webmd.com/mental-health/news/20040526/did-michelangelo-have-autism
- Futurity. "Monkey Brain Signals Mental Wanderlust." (Feb. 1, 2013) http://www.futurity.org/science-technology/monkey-brains-signal-mental-wanderlust/
- Hsu, Christine. "Scientists Find Truth in 'Mad Scientist' Stereotype: There is a Link Between Genius and Insanity." June 4, 2012. (Feb. 1, 2013) Medical Daily. http://www.medicaldaily.com/articles/10149/20120604/genius-insanity-schizophrenia-bipolar-disorder.htm
- Knapp, Alex. "Nikola Tesla: Unique Genius or a Model for Everyone?" April 28, 2011. (Feb. 1, 2013) Forbes. http://www.forbes.com/sites/alexknapp/2011/04/28/nikola-tesla-unique-genius-or-a-model-for-everyone/
- National Alliance on Mental Illness. "What is Mental Illness?" (Feb. 1, 2013) http://www.nami.org/Template.cfm?Section=By_Illness
- National Institute of Mental Health. "Common Gene Version Optimizes Thinking -- but With a Possible Downside." Feb. 9, 2007. (Feb. 6, 2013). http://www.nimh.nih.gov/science-news/2007/common-gene-version-optimizes-thinking-but-with-a-possible-downside.shtml
- PBS. "American Experience: John Nash." (Feb. 1, 2013) http://www.pbs.org/wgbh/amex/nash/peopleevents/p_jnash.html
- Science Daily. "Link Between Creativity and Mental Illness Confirmed in Large-Scale Swedish Study." Oct. 16, 2012. (Feb. 1, 2013) ScienceDaily. http://www.sciencedaily.com/releases/2012/10/121016084934.htm
- Tesla Memorial Society of New York. "Tesla Biography. (Feb. 10, 2013). http://www.teslasociety.com/biography.htm
- Waugh, Rob. "There is a Link Between Genius and Madness, Claim Scientists." June 4, 2012. (Feb. 6, 2013) Daily Mail. http://www.dailymail.co.uk/sciencetech/article-2154393/There-IS-link-genius-madness-claim-scientists--dont-know-evolved-gift.html