Anecdotally people share how marijuana use turned a high performing, eager person into a slug. Images of a consumer laying on a couch with empty bags of chips fill pictures with people assume to a be a “regular” partaker. But is this true? Does science back up the impression? Globally, marijuana is third behind alcohol and nicotine in consumed controlled substances.
Like alcohol and other intoxicants, early use of cannabis causes less development in brain functions. It is widely accepted in the medical world, they should avoid intoxicants until there are into there 20s to allow the brain full functioning abilities.
Day drinking alcohol can make you feel drowsy or lethargic. If you didn’t sleep well the night before, even one drink can make you drowsy, especially if you drink during one of your usual low-energy times such as midafternoon or late evening. Alcohol produces chemical imbalances in specific neurocircuits and can be neurotoxic.
Chronic heavy drinking can, for example, damage brain regions involved in memory, decision-making, impulse control, attention, sleep regulation, and other cognitive functions.
Like alcohol, casual marijuana use can have short and long term effects on the brain and behavior. There have been few studies examining the link between cannabis and motivation using performance-based measure. But there is a difference between casual and heavy use.
But there is one key element. Cannabis use in humans is associated with reduced dopamine in the striatum. Dopamine is responsible for allowing you to feel pleasure, satisfaction and motivation. When you feel good that you have achieved something, it’s because you have a surge of dopamine in the brain. PET studies have shown lower striatal dopamine synthesis and release capacity in cannabis users.
Alcohol use overloads the brain with dopamine, while also reducing the brain’s dopamine receptors in the process. This makes quitting alcohol difficult.
Researchers found dopamine levels in a part of the brain called the striatum were lower in people who smoke more cannabis and those who began taking the drug at a younger age.
They suggest this finding could explain why some cannabis users appear to lack motivation to work or pursue their normal interests.
It seems causal use has little effect, but dependence can have long term issues that would need to be addressed. This is not unlike alcohol.