A recent article in New York Times Magazine looked at the effects of marijuana on brain structures. A joint study out of Harvard and Northwestern University found evidence of structural changes in the brains of participants who smoked Marijuana. The study looked at brain scans of 40 young adults, half of whom were nonusers and half reported smoking for one to six years and who showed no signs of dependence. Of the smokers, seven were light smokers, nine used three to five days a week and four used daily. The results showed that all the individuals who smoked displayed abnormalities in the shape, density, and volume of the nucleus accumbens and amygdala. The nucleus accumbens is responsible for motivation, pleasure and plain, and the decisions we make, and the amygdala is essential for processing emotions, memories and fear responses. What the findings indicate is that the effects of THC are longer lasting than previous believed. There is a common belief that marijuana is harmless and it is not addictive, and with healthy adults this seems to be the case. However, with the higher potency levels in THC and rising usage amongst teenagers, when their brains are developing into the mid-20s, there is an increase in learning and mental health problems.
Moore, A.S. (2014, October 29). This is your brain on drugs. New York Times Magazine