The New Field of Neurodiversity: Why 'Disabilities' Are Essential to the Human Ecosystem
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Just as niche construction for animals consists of a wide range of strategies—nests, holes, burrows, paths, webs, dams, migration patterns and more—so niche construction for human beings is likewise diverse. Choices about lifestyle or career may be among the most critical in determining whether a person suffers as a disordered individual or finds satisfaction in an environment that recognizes his strengths.
One of the worst career choices for a person with attention deficit hyperactivity disorder, for instance, would probably be a nine-to-five desk job in a large and impersonal corporate office. Without an opportunity for movement, the person’s ADHD symptoms would stick out like a sore thumb. This would be a good example of poor niche construction.
On the other hand, if that individual were to pick a job that involved speed, novelty, change and physical activity, factors associated with the strengths of ADHD (a delivery person, for instance, or an itinerant photographer), it is likely that the symptoms would not even be regarded as problematic but would be seen as positive traits useful in the workplace.
Similarly, for a person with dyslexia who possesses spatial strengths, working with words at a computer all day long in a legal firm would likely be much more stressful and incongruent than spending time engaged with a computer graphics software program in an architect’s office.
This raises another set of strategies important in building a good niche for the neurodiverse brain: assistive technologies. These refer to a wide range of high-tech tools, including computer hardware, software and peripherals, that enable individuals with disabilities to perform tasks that they were previously unable to accomplish. The Kurzweil hand-held reader, for example, scans printed texts and transforms them electronically into the spoken word. This enables people with severe dyslexia (as well as the blind) to access a whole world of print previously inaccessible to them. For individuals with ADHD or anxiety disorders, neurofeedback devices help focus attention and facilitate deep relaxation.
– 8 – Positive niche construction directly modifies the brain, which in turn enhances its ability to adapt to the environment
In the late 1960s at the University of California, Berkeley, biological psychologist Mark Rosenzweig and neuroanatomist Marian Diamond engaged in an experiment that was pivotal to the field of neuropsychology. They placed rats in different environments (or “niches”) for an extended period of time. Some of the rats were in “enriched environments” consisting of large cages with stimulating activities such as mazes, ladders and wheels. Other rats were put into less enriching environments where they were either alone or with only one or two cage mates and no available stimulation.
After several weeks, the brains of the rats were dissected and studied. Rosenzweig and Diamond discovered that the rats in the enriched cages had more synapses, or brain connections, than those in the less stimulating cages. It turns out that the environmental experiences of the rats directly changed their brain structure.
Since that time, we’ve learned a lot about the powerful influence of environment on brain development, particularly in the early years. We know that environmental adversity (including family conflict and parent criminality) is associated with a greater risk of ADHD. We know that a young child who has an episode of depression is at greater risk of having a second episode because of the “kindling effect,” wherein the emotional trauma of the first depression sparks changes in the brain’s chemistry that make a second depressive episode more likely.
On the positive side, we know that early intervention in autism can increase a child’s chances of significantly improving social functioning, and that a warm home environment in childhood provides a buffer against depression.