Marijuana reduces brain dopamine, experts say
A recent study shows sufficient evidence that marijuana can significantly affect brain function. Cannabis usage reduces brain dopamine levels which are associated with mood changes, fatigue, depression and lack of motivation. Likewise, low levels of dopamine are also found in many neurological diseases like Parkinson's disease and Attention Deficit Hyperactivity Disorder or ADHD.
Dopamine is a neurotransmitter released by the brain that plays a number of roles in humans and in other animals, such as movement, memory, pleasurable reward, behavior, and cognition, attention, inhibition of prolactin production, mood, sleep, and learning.
Since the legalization of cannabis for recreational and medicinal purposes are increasing around the world, researchers are keen in their studies to learn more about the effects of the drug in the human brain.
Based on the article in Healtheo360, Study leader Prof. Olive Howes of the Medical Research Council Clinical Sciences Center at Imperial College London in the UK, and his team, conducted a review of numerous studies investigating how the primary psychoactive compound in cannabis, tetrahydrocannabinol (THC), affects the brain.
The results of the research obtained a substantial evidence that a long-term exposure of THC can decrease the level of dopamine in the brain.
"The available evidence indicates that THC exposures produces complex, diverse and potentially long-term effect on the dopamine system." The authors of the study also explain that in response to an acute THC exposure, it will increase the nerve firing and dopamine release, and dopaminergic blunting associated with its long-term use.
The researchers also believe that people who engage in a long-term marijuana use are at risk for mental health problems - psychoses.
According to NCPIC, psychoses refers to a group of mental illnesses where people experience difficulty in distinguishing what is real and what is unreal. An individual who is suffering from psychosis might hear voices or see/taste/smell which doesn't (hallucinations) or have beliefs that are not true (delusions). Hallucinations and delusions are both accompanied by confused thinking and speech, making a person so difficult to understand and to function in life.
Schizophrenia is the most known in the group of mental illnesses. Cannabis has been clearly shown to make psychotic symptoms worse in people who already have psychotic disorder. Any use of cannabis can double the risk of schizophrenia in those who are vulnerable, and bring on the first episode up to two and a half years earlier.
While some people use cannabis to alleviate the symptoms of depression, evidence shows that smoking marijuana may also aggravate depression. Frequent or heavy use of cannabis predicts depression in later life.