The fractal of basal ganglia

The Basal Ganglia can have two parallel circuits which run in conjunction with each other. Motor activity is dependant on the balance between these circuits. One is the venteromedial group of nuclei which have a large input from the limbic cortex. The other group is the dorsolaterlal group of nuclei which have their major input from the frontal lobe. The names of these two groups of nuclei are quite illustrative based on the framework one would want to differentiate them on. In an evolutionary framework, the venteromedial is earlier in development compared to the dorsolateral. Hence its functions are more “primitive” and “less sophisticated” than the dorsolateral counterpart. The dorsolateral pathways can manage inhibition of behaviors as well as activation of behaviors. The venteromedial pathways only manage disinhibiting behaviors. In terms of position also it resides “inwards” compared to the more “outwards” position of the dorsolateral structures. The venteromedial deals more with the inner feelings, hence the connections from the limbic system while the dorsolateral deals with the outer realm of things.
In Obsessive Compulsive Disorder, the venteromedial system is over-activated and an increase in disinhibition can result. This is typified by the disinhibited patterns on behaviors which are termed as compulsions. They can range from counting, checking, hoarding or cleaning. It is a hypothesis that behavioral therapy strengthens the dorsolateral pathways, especially the part which is able to inhibit behaviors.

The dynamics of a person with OCD revolve around behaviors which are dysfunctional. Dysfunction means that the behaviors do not help an individual adapt to the external reality. All behaviors are being driven by the limbic system, or the internal cues. The example is of an autistic child who tries to answer everything in his or her framework. Evolutionary it serves a function of shutting of the “thinking mind” in dangerous situations and the result is an uncontrolled motor activity which is avoidant. The dysfunction comes when this behavior goes on without any danger present in the external environment. Think of a deer that runs regardless of whether it is facing a predator or green pastures.

The balance problem with these structures represents a fractal and this fractal at different level points to a similar dysfunction seen in psychiatric patients. The psychiatric patient engages in similar dysfunctional behaviors in its interaction with other people. There is a reason why Freud called it symptom compulsion. Dr Gustafson has called it the mismatch between the internal and the external world. Think of the system that has figured out how to make profits. Every thing which is not a loss is a profit and since profit is better, all activity will be utilized to get profit. Anything that is not profit is not an activity to be engaged in. The pack will continue to increase to the point of dysfunction.

In an alternative view the venteromedial system could represent the channeling of id. Not all of those behaviors are functional in nature and it requires the functioning of a counterbalance of superego (dorsolateral) system when to inhibit behaviors, control impulses or engage in increased activity in the service of adaptation.

Mature defenses like suppression, humor, sublimation, altruism and asceticism all involve the ability to suppress the internal urges to an extent. However a couple of them like humor, sublimation and altruism actually involve behavior which is adaptable based on the cues of the environment.

However when thinking about this a certain flexibility is required. Implementation of a prefect solution no matter how elegant will run in to failure (and the be the perfect example of the basal ganglia in OCD) the moment consciousness to the uniqueness of a situation is disregarded.