A model of risk for mental disease in neurodiverse people

There has been a sharp rise in mental health problems particularly in children and teenagers in the past decade. The increase in ADHD and ASD and related symptoms is becoming hard to explain by improved diagnostic procedures alone. The starting point for our model is the resemblance and overlap of many mental problems ranging from ADHD to ASD as well as their frequent comorbidities, such as social anxiety , sensory processing disorder and depression . The objective is to unify existing models of neurodiversity with the hunter-gatherer neurotype hypothesis.

Thom Hartmann’s hunter-hypothesis for ADHD is widely known. Its core idea is that people with ADHD have a different type of cognition, in particular attention focus. While early farmers had to be able to focus on long routine work, hunter-gatherers were better off with a “radar mind”, that hyperfocused when, say, a deer was spotted. The difference is, therefore, bouts of hyperfocus on high-interest objects vs constant focus on boring routine work. This hyperfocus can also be observed in people with ASD when they engage with their special interest, as well as in gifted and highly intelligent people, who tend to reflect much longer on unexplainable phenomena than neurotypicals.

If people with ADHD have ancient hunter-minds, why not also people who have one of the related mental disorders? We know that mental diseases run in families. What is often surprising is that it is hard to predict which mental disease will appear in a family. If a father has autism, one of his children might well end up with schizophrenia or major depressive disorder. Einstein had a hunter-mind and was almost certainly on the spectrum, comorbid with ADHD (inattentive). Einstein’s first son, Hans-Albert became a successful engineer and university professor, not uncommon for hunter-minds. Einstein’s second son Eduard was highly sensitive and poetically inclined — suffered from schizophrenia, less common for hunter-minds, but perhaps more common for ancient gatherer (female, caregiving-profile) minds.

The pattern that emerges here is that giftedness and mental diseases often run in families and that while they may co-occur in the same person, they may also bifurcate, creating a successful life-trajectory or one that makes a successful life-trajectory very hard to achieve. These hunter-gatherer minds might be the very same people that Thomas Boyce (2020) identified as orchid children, who in turn might be the very same individuals who had highly reactive temperaments as babies (Kegan, 2004). These highly reactive or difficult babies are known to have a shy temperament later on and have a higher vulnerability to mental disease. Another convergent line of research is Ruth Karpinski’s (2018) model of hyperbrain and hyperbody. It states that high IQ people have a high risk for diseases, both mental and physical (autoimmune, allergies, inflammations), due to high-stress reactivity and high cortisol levels.

Some people seem to be more prone to autism , whereas others seem to be more prone to schizophrenia. Simon Baron-Cohen (2004) has noticed that people with autism often have an extreme male-systemizing brain. This is true for the majority of both male and female persons with ASD. The famous Temple Grandin, for example, has a highly systemizing and visual mind. Such an extreme male brain often goes together with a lack of social and verbal skills. Testosterone could influence the trajectory of a mental disorder. ASD, ADHD and ODD are all more common in males than in females. If there is an extreme male brain that has a higher risk of mental disorders, could there also be an extreme female brain susceptible to mental disorders? In Baron-Cohen’s model, the opposite of an extreme systemizing brain is an extremely empathizing brain, dominated by estrogen. In fact, empaths (more often women than men) and highly sensitive people have a higher risk of mental problems (in particular related to depression and anxiety) and make up the majority of people in psychotherapeutic treatment (Elaine Aron, 2017). Men can also have a more “feminized” brain, which is often correlated with a feminized digit (2D:4D) ratio, whereas women can have a more masculinized brain that correlates with a lower digit ratio.

Henry Markram is another researcher who has postulated that brains of people with ASD feel rather too much rather than too little (overexcitability). This is called the intense-world theory of autism . I agree with Markram’s analysis. Hunter-gatherer type minds, in general, are highly excitable with deep neural processing and a hyperactive amygdala (stress-response). These traits are most likely adaptations to a hunter-gatherer lifestyle that was at least partially lost or modified when people took to farming.

Crespi and Badock (2008) have developed a model of ASD and psychosis as diametrical disorders of the social brain . In their model social cognition is underdeveloped in autism spectrum disorders and overdeveloped in psychotic spectrum disorders (schizophrenia, bipolar disorder and major depression). Their model is therefore highly congruent with ours. We would subsume ASD, ADHD and ODD under the “hunter-type disorders, as in all three of them males are overrepresented and it therefore likely that testosterone plays an important role in their development. Anxiety disorders are more common among females than males, however, the bias is not as strong as for ASD and depression.

From all the above research the following model of hyper-systemizing hunter and hyper-empathizing gatherer brains with differential risk to mental diseases can be derived:

I estimate that about 20% of the population are neurodiverse, with more than half of those people unaware of the fact themselves. This is the reason why people with ASD are often initially relieved when they receive their diagnosis. All their life long they had had a feeling that there was something wrong with them. Unfortunately, this initial relief doesn’t last long when it becomes obvious that a diagnosis doesn’t change anything about their misery.

The 20% mark is a recurrent one: 20% of babies are highly reactive, 20% of people are highly sensitive and about 20% of people are intuitives in the Myers-Briggs inventory. I have argued in previous posts that these intuitives have highly egalitarian hunter-gatherer minds.

All this is not to say that other neurotypes — i.e. farmer and herder according to our ancestral modes of subsistence — can’t suffer from any of these mental problems, they are just much less likely to do so.

References:

ARON, E. N. (2017). HIGHLY SENSITIVE PERSON . Place of publication not identified: HARPER THORSONS.

Baron-Cohen, S. (2004). The essential difference . London: Penguin Books.

BOYCE, W. THOMAS. ORCHID AND THE DANDELION: Why Sensitive People Struggle and How All Can Thrive . BLUEBIRD, 2020.

Crespi, Bernard and Badcock, Christopher (2008). Psychosis and autism as diametrical disorders of the social brain. Behavioral and brain sciences, 31 (3). pp. 241–260. ISSN 0140–525X

Hartmann, Thom, and Michael Popkin. ADHD: a Hunter in a Farmer’s World. Healing Arts Press, 2019.

Kagan, Jerome, and Nancy C. Snidman. The Long Shadow of Temperament . Harvard University Press, 2004.

Karpinski, R. I., Kolb, A. M., Tetreault, N. A., & Borowski, T. B. (2018). High intelligence: A risk factor for psychological and physiological overexcitabilities. Intelligence, 66 , 8–23. doi:10.1016/j.intell.2017.09.001

Markram, H. (2007). The intense world syndrome — an alternative hypothesis for autism. Frontiers in Neuroscience, 1 (1), 77–96. doi:10.3389/neuro.01.1.1.006.2007

Originally published at http://the-big-ger-picture.blogspot.com on September 12, 2020.