Obsessive-Compulsive Spectrum Disorders
Consider this: The ability to shift from one activity (e.g., doing one’s taxes) to another (e.g., answering the phone) involves inhibiting the first activity to pursue a second activity and results in the production of new sequences of behavior. Repetitive stereotyped activities, such as obsessive-compulsive behavior and Gilles de Tourette syndrome, indicate the malfunctioning of this system. To put it baldly, you’re literally stuck in a cliched set of actions without recourse from your manual tyranny: Addictive behaviors (gambling, some forms of market investing, drugs, and sex) are a common example, but you also see individuals engaged in stereotypical thinking: For instance, about politics, about relationships, about how to carry out a particular procedure at work, about what car to purchase, where to live, what to wear, and so on. In psychiatry, these are grouped together as OCD (“obsessive-compulsive disorder”) spectrum disorders: Gambling, paraphilia (sexual fetishes), body dysmorphic disorder (e.g., thinking you’re fat when you’re thin), trichotillomania (constant hair-pulling), hypochondriasis, somatization disorder (frequent psychosomatic complaints), Gilles de Tourette syndrome (motor and vocal tics), autism, kleptomania, impulse control disorders, obsessive-compulsive personality disorder, bulimia, and anorexia nervosa.
The cortex (namely, the orbitomedial frontal cortex), the subcortex (particularly a set of structures known as the basal ganglia), and the body work together in communion with the social and physical environment to accomplish everyday intellective tasks. The orbitomedial frontal cortex is involved in inhibiting socially inappropriate behaviors and freeing the mind from distractions for the task at hand. The basal ganglia, located deep within the interior of the brain, dynamically modulates behavior based on feedback from the motor and affective systems and from our various external sensory modalities (touch, vision, audition, olfaction, and gustation) — the body. These two brain structures are intimately connected and cutting their nerve fibers, as it turns out, is sometimes useful with patients with refractory OCD.
Indeed, a malfunctioning basal ganglia leads to stereotyped movement patterns and the absence of novel behaviors. One patient I treated had obsessive thoughts that he was going to be infected with a sexually transmittable disease from casual sex (OCD) and another I observed in a clinic was a compulsive swearer (Gilles de Tourette syndrome). The first gentleman was a particularly interesting clinical case because he grew up in a home where his father was a compulsive gambler and continually stole money from his wife and two sons. As a result, the family was always broke and family finances — like mortgage, electric, and gas payments — were often unmet. The twin brothers, who were identical twins, both suffered from OCD. The mother was the only so-called “normal” individual in the family. It must have been quite difficult for her raising a family of compulsive gamblers and “ideators.” In both cases, the basal ganglia along with the orbitofrontal cortex, constrained the father’s and the sons’ ability to switch mental set and each one of them were mentally “stuck” in one mode or the other of responding to the world. In the case of the two twins as it turns out, the actions of the first sibling led to certain thoughts (i.e, obsessive thoughts about being infected with a sexually transmittable disease) and the thoughts of the second led to certain actions (the second sibling was a compulsive hand washer).
Clomipramine (“Anafranil”), a nonselective serotonin reuptake inhibitor (NSRI), can be an effective treatment for OCD. However, about 40% of patients with obsessive-compulsive disorder do not respond to either NSRI or selective serotonin reuptake inhibitor (SSRI) treatment. This may be so because some forms of obsessive-compulsive behavior are a result of excessively high levels of dopamine, not serotonin. High doses of dopaminergic drugs that increase production of dopamine in the brain (e.g., amphetamine, apomorphine, bromocriptine, and L-DOPA) appear to increase stereotypical movement and compulsive behaviors in humans in one of four dopamine pathways, the nigrostriatal pathway. On the other hand, another dopamine pathway, the mesocortical pathway, appears to be involved with some of the “cognitive” symptoms of OCD, such as obsessive thoughts. Genetic studies suggest that these kinds of obsessive-compulsive disorders are highly heritable. As a result, it is often difficult to treat OCD individuals with supportive psychotherapy alone so treatment is often augmented with the use of psychoactive drugs.
What about everyday risk-taking? Many forms of gambling and stock speculation (e.g., investing in stock options and mortgage-backed securities), high-risk activities (such as bungee jumping, rock climbing, cave exploration, and parachuting), and similar pursuits probably arise from deep roots in human nature that are affected by culture, age (adolescence), and experience. They have many positive benefits and some negative effects and potentially lurk within all of us. To be sure, a sobering thought.
Some suggesting readings:
(1) American Psychiatric Association. (2000). Diagnostic and statistical manual of mental disorders (4th ed., text revision). Washington, D.C.: American Psychiatric Association.
(2) Horwitz, A. (2002). Creating mental illness. Chicago: University of Chicago Press.
(3) Stahl, S. M. (2000). Essential psychopharmacology: Neuroscientific basis and practical applications (2nd. ed.). Cambridge: University of Cambridge Press.