A recent study, that showed how cigarette smokers kicked the habit spontaneously after they suffered a brain stroke or injury, has helped map regions within the cranium that control addiction of any kind. The research, published in the scientific journal Nature Medicine and quoted by the New York Times, says how certain scans, while showing the damage caused by a clinical episode, also exposes “plots of brain regions where an injury miraculously relieves someone’s symptoms, offering clues about how doctors might accomplish the same.”
Clearly, this helps us work on a targetted approach in all kinds of addiction treatments and helping people quit smoking. As one of the study’s lead authors, Dr Juho Joutsa, neurologist at the University of Turku in Finland, said, “One of the biggest problems in addiction is that we don’t really know where in the brain the main problem lies that we should target with treatment. We are hoping that after this, we have a very good idea of those regions and networks.”
These imaging studies have revealed neurochemical and functional changes in the brains of addicted subjects that provide new insights into the mechanisms underlying addictions.
Neurochemical studies have shown that large and fast increases in dopamine are associated with the reinforcing effects of addiction but also that after chronic drug abuse and during withdrawal, brain dopamine functions are markedly decreased and these decreases are associated with dysfunction of pre-orbital regions.
Functional imaging has shown that during intoxication or during craving, these frontal regions become activated as part of complex patterns that include brain circuits involved with reward. Attempts to understand and treat addictions as purely biological or purely environmental problems have not been very successful. PET can be used to measure labelled compounds that selectively bind to specific receptors, transporters or enzymes types of concentration that do not perturb function. Most PET studies of any kind of addiction have a concentration on brain dopamine systems since this is considered to be a neurotransmitters system through which most drugs of abuse exert reinforcing effects.
During intoxication, there is a complex pattern of activation and/or deactivation that includes the ventral tegmental area and the substantia nigra where DA cells (dopamine cells) are located. This study highlights the same fact that addiction is associated with elective pulses to the brain. A stroke or trauma may suggest that nicotine addiction may be dependent on a large dependency. This could be a major target for addiction treatment that delivers electric pulses to the brain and has shown promising results to quit smoking. It is understandable to presume stroke involving the addiction centres like the amygdala central trigeminal area or substantia nigra (deep-seated white matter nuclei which produces dopamine) can lead to loss of craving for nicotine or cocaine, eventually leading to de-addiction.
