These are the brains of various substance users, alcohol is seen to be incredibly damaging even in weekend only drinking, while marijuana use has an effect observed similar to caffeine. On the right are alcoholic and various other drug users. Using four times a week over the period of three years, this heavy drinker's brain is scalloped out, and damage to the blood circulation in the brain is apparent. In a normal person without any substance use and in continued sobriety, seen at the beginning, there is no damage to the circulation of the brain. Due to statistics suggesting infection from toxoplasmosis, the information provided here regarding marijuana, which is frequently homegrown may be incorrect, however it does show that marijuana use is equivocal to the effect of caffeine with responsible adult use. For those who experience more negative results with marijuana, potential toxoplasmosis gondii infection and hard substance use should be investigated (as both are linked and causal factors in schizophrenia and other disorder cases) and childhood history should be gathered and confirmed using a blood test for the stress hormone cortisol as well, as elevated cortisol levels have been identified as a primary causal factor in adult psychotic depression, and in childhood trauma victims, will be permanently higher (Belanoff). The scan remains an excellent example of light alcohol use as well as the impact of potential parasitic infection from using marijuana in a decriminalized or illegal setting. [Article from News Illustrated, 2013]
With the alcohol and other drug users, this looks like swiss or cottage cheese after decades or years of abuse. Interestingly and significantly, an example of a weekend only drinker is provided. The brain still looks completely decimated by the alcohol use, dismissing the concept that just sometimes using alcohol limits or reduces the damage done by the neuro-toxins present in alcoholic beverages. I wondered what might occur with light marijuana use (and much less alcohol use).
After about a year of sobriety (enough time for the circulation of the brain to return completely to normal), this experiment involved use of one half to one full ounce of marijuana and around 36 beers over a 6 month period and getting a single photon emission computed tomography scan which accurately shows brain function and substance use.
Source: The Hanley Center, Amen Clinic, Siemens
First, it is necessary to look at a brain with bad habits and excessive caffeine use, this is a baseline:
Marijuana and alcohol use:
Over a six month period, occasional use of around 36 beers, seen following, moderate non-consecutive use and between one half and one full ounce of marijuana, medium quality consumed less than one half of a gram at a time. The damage to blood flow in the brain is clearly beginning in the same areas as that exhibited by an alcohol and marijuana user, though only a fraction of the levels as displayed through heavy use, and consistent with caffeine use. This indicates positively that light substance use has a legitimate and severe negative impact on multiple areas of cognitive and motor skill functioning as well as emotional processing, but is not nearly to the same level as some research has claimed. It must be noted, however, that in a legal setting the impact of pesticide and parasite free marijuana may be completely different from alcohol, and some studies have connected current light marijuana use, that is responsible adult use (5-10 grams per week in Fried et al.) with an increase in IQ (though alcohol remains negative regardless of legality). The scalloping seen on the top of the head is light, and most likely caused by alcohol consumption, along with reduced circulation to decision making and memory functions which are likely caused and exacerbated by marijuana consumption as well, though retrospective research using MRIs suggests that marijuana use may actually increase connectivity and alleviate these symptoms. There is currently no permanent structural damage, as expected as well. No significant history of physical brain trauma, ie. head injury or medical problems to rule out. Some prior use of hallucinogens including absinthe, but several years past and not apparent in this scan. It can also be mentioned before the experiment light alcohol use for 3.5 years and marijuana use for 5 years. The subject was 22 years old, and the brain seen is nearly complete in development, giving an accurate view of the substances involved.
Second Addendum: Results may not be reproducible as lead contamination in marijuana has been confirmed in both Germany and the Northeast of the USA, both of which are regions in which the subject consumed marijuana under decriminalization procedures, a practice carried out by dealers of the historical artifacts to increase profits and potency. A similar research experiment in these regions recorded blood lead levels of around 3.5 micrograms per deciliter one month after cessation and urine THC levels were over 500 ng/mL (or over 10 times the level recorded in a chronic user 12 hours after use), suggesting the high core temperature of a lead-infused joint (1200 degrees centigrade vs. 700 in a cigarette or 500 in pipe tobacco) resulted in significantly more THC absorption than was previously believed. This is confirmed from studies on tobacco which show the absorbed nicotine from cigarettes is 5X greater than that of pipe tobacco, though research on THC absorption as a result of different incineration temperatures is not yet available. Finally, a case-study from Romania has recently shown that the short-term effects of THC are also positive, increasing alertness and even overwhelming the effect of "significant" alcohol intake, which decreased alertness until administration of THC brought the subjects to a level of cognitive functioning even above a control baseline level.
Imaging by Eclipse Nuclear Medicine
Facility: The Hanley Center
Affiliations: Undergraduate research completed while enrolled at the University of Vermont, no declared affiliations.
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