Tag Archives: Cannabis Neurochemistry

Marijuana: Neurochemistry &Physiology

After years of fierce debate, increasing amounts of objective, non- judgmental research is available although it is made difficult due to the complexity of the cannabis plant. Cannabis contains hundreds of different molecules. The plant is able to synthesize these cannabinoid compounds which is a family of 150 cannabinoids including the very well known compound THC. 

Though these compounds can affect many physical functions in the body, it is mostly used recreationally. 


Cannabis has many strains with various terpene profiles, however, many botanists believe there are just three species of Cannabis plants. 

Cannabis sativa, a tall plant that is grown throughout the world. It can be cultivated to produce large amounts of THC, the chemical that produces psychic effects. It can be grown, as it has been for thousands of years, or indoors.

Hemp, a source of fiber for rope, concrete, plastic and cloth. Hemp plants contain minimal amounts of THC. they grow rapidly to large sizes and provide sustainable, scalable and eco-friendly material solutions.

Cannabis indica, a short pungent plant often called skunk weed, with high concentrations of THC and a distinct terpene profile. It is especially plentiful in India and the Middle-east though it can be grown anywhere. It is usually the source of hashish and other concentrates or extracts. 

Cannabis ruderalis, found mostly in Central Asia, but it has no use as a fiber and its psychic effects are minimal. In an effort to increase the plant’s potency, cannabis growers use the sinsemilla technique. This method prevents the female plants from being pollinated by the male plants thus increasing the concentration of THC. 

Brain Chemistry 

Stronger varieties of cannabis can produce distortions of time, color, and sound. As with other psychoactive compounds, cannabis’s botanical compounds mimic neurochemicals that exist naturally in the human body and brain. These internal brain chemicals are called endogenous cannabinoids or endocannabinoids.

The first one discovered was anandamide followed by 2 arachidonoylglycerol designated 2AG. Generally, there are 10 times the amount of anandamides in our body and brain as there are the endorphins. Anandamides are  involved in a huge range of functions, they work to modulate and modify, by either increasing or decreasing the sensitivity of our mind.

Anandamides, like all neurotransmitters, help transmit messages from one nerve cell to receptor sites on an adjoining nerve cell. This combination of electrical and chemical signals within the 100 billion cells that make up the central nervous system, help the brain communicate with the outside world through its senses and within itself through memories, emotions, and thoughts. 

Endocannabinoid System

So far, researchers have conclusively identified 2 types of receptor sites: the CB1 and CB2 receptors. The CB1 receptors are found primarily in the brain and their activation results in the psychoactive effects of cannabis. This is because THC mimics anandamide, the endocannabinoid that naturally activates these receptors. 

CB2 receptors are found throughout the body and are much more involved in changing the ocular pressure, heart rate, blood pressure, and pain sensitivity. 

By understanding the neurochemical and physiological effects of cannabis, it is possible to make better judgments about the possible cannabis use or refined cannabinoids for medical applications. 

By extracting and isolating these molecules from cannabis we can focus only on the ones that have the medicinal potential.

Cannabinoid Stimulation


One part of the brain rich in endocannabinoid receptors is the amygdala, found in the brain’s emotional center. A crucial function of the amygdala is to signal a sense of novelty particularly when one encounters a new situation, idea, or even new surroundings.  

As the amygdala is continually stimulated with THC, the CB1 receptors respond with delight. With excess use, these cells react to the overstimulation by retracting into the cell membrane and becoming inactive (self regulation). This process is known as down regulation. 

Once receptor sites are down regulated, it takes approximately two weeks for them to recover. This reversible process can help in fighting mood disorders.

Reward/Reinforcement Center 

Has high levels of endocannabinoids and CB1 receptors. When stimulated, a cascade effect bathes the core of this system, the nucleus accumbens, in dopamine, causing a feeling of accomplishment or gratification. These mechanisms are limited by tolerance.  


The highest concentration of cannabinoids in the body is the hippocampus. The hippocampus is involved in short term memory conversion to long term memory. 

Neurons produce endocannabinoids to shut off memory because we can not remember everything. When we overstimulate, it actually cuts down on the amount of short term memory and changes the frontal lobe activity responsible for decision making. Regulating cannabinoid receptors is key for future medical use.

Motor Activity

A third area of the brain that has very high concentration of cannabinoids naturally is in the basal ganglia and the cerebellum, involved in controlling motor activity to relaxe the muscles and reduce pain. Overall causes a decreased reaction time to situations and slows physical movements. This can be regulated by changing the affinity and concentration of cannabinoids in the system. 


Generally there are two main cannabinoids, THC and CBD. these cannabinoids work synergistically and affect the ability to follow moving objects and effects the ability to carry out complex tasks. 


The  endocannabinoids regulate appetite by the level of stimulation they cause in a set of CB1 receptors in the hypothalamus. By stimulating the receptors appetite is greatly increased. Research indicates that blocking selective CB1 receptor sites instead of stimulating them, causes a reduction in appetite and significant weight loss. 

Respiratory Effects

Cannabis alters  the immune defenses against infection. While smoking is always bad for the lungs, cannabis contains compounds that lower inflammation and fight bacterial infections.

Psychological Effects 

Cannabis has been reported to improve neurocognitive and psychiatric conditions, such as Alzheimer disease, anxiety disorders and bipolar disorder.

In addition, potentially reducing PTSD symptoms, cannabis also mitigates the propensity for inflammation and may be useful in psychological conditions that involve elevated inflammatory processes within the brain.


Cannabis works on the Endocannabinoid System. Compounds such as terpenes help change the affinity of the cannabinoids to the respective receptors. The medical applications are vast. As we understand more about various mechanisms in our body we uncover further benefits.