Despite being non-psychoactive, CBD has many different effects on the brain.
Cannabidiol (CBD) is a non-psychoactive chemical produced by the cannabis plant. It is the second most common chemical found in marijuana, after the psychoactive ingredient THC.
While most people think of THC when thinking about marijuana, CBD is becoming more popular because of its wide range of health benefits.
As a result, many cannabis breeders have started to focus on increasing CBD levels in the strains they produce. Some newer strains of cannabis, such as Charlotte’s Web and Avidekel, now contain more CBD than THC.
But how exactly does CBD work in the brain? Let’s take a look at the science.
Activates the Endocannabinoid System
The endocannabinoid system consists of a group of molecules and receptors that occur naturally in the body. The system is composed of CB1 receptors which are found mostly in the brain, and CB2 receptors that are found mostly on immune cells.
When marijuana is consumed, compounds like THC and CBD travel through the bloodstream to the brain and activate the endocannabinoid system.
In the brain, THC binds to CB1 receptors to produce many psychological effects. These effects include short-term memory impairments, heightened mood, increased hunger, and pain relief.
The role CBD plays in the brain is both interesting and complex. For example, unlike THC, CBD does not have psychoactive effects. This is because CBD does not activate CB1 receptors.
Instead, CBD interacts with CB1 receptors in a way that prevents other compounds like THC from binding to the receptor. As a result, CBD reduces many of the effects of THC, such as anxiety and memory problems.
CBD also increases anandamide levels in the brain. Anandamide is one of the few cannabinoids found naturally in the human body.
Anandamide is responsible for regulating levels of other chemicals found in the brain, including serotonin and dopamine. By increasing anandamide levels, CBD ultimately regulates other important neurotransmitters as well.
Helps Anxiety and Depression
Many cannabis users are familiar with the drug’s ability to relieve stress and promote relaxation. While THC can make some people feel more relaxed, it also seems to increase anxiety in others. This has led researchers to focus on CBD as a treatment for anxiety and depression.
In one human study, researchers used imaging scans to understand which brain regions are involved with CBD’s anti-anxiety effects.
They found that CBD causes a reduction in blood flow to specific regions of the brain linked to anxiety, such as the hypothalamus. These regions typically become overactive in anxiety disorders, whereas CBD seems to quiet their activity. CBD was also effective at reducing the overall anxiety scores of participants in the study.
Besides reducing anxiety, CBD has been found to work as an antidepressant.
This has opened the door for clinicians and patients alike seeking alternative ways of treating depression. Unlike CBD, current antidepressant medications have significant side effects and may take several weeks to begin working.
Reduces Pain and Inflammation
While the pain-killing effects of THC have long been known, recent studies show that CBD can reduce pain too.
One study investigating the ability of a CBD ointment to treat pain in arthritis found that the drug reduced both joint inflammation and spontaneous pain. The study also found that CBD was better absorbed into the blood when it was applied as an ointment, since it avoids being metabolized by the body.
One of these functions involves suppressing the inflammation response produced by the immune system. This reduces the amount of inflammatory molecules, such as cytokines and chemokines, that occur at sites of inflammation.
By reducing inflammation peripherally, CBD is able to block pain signals from being sent to the brain.
Protects Brain Cells From Harm
In fact, the U.S. Department of Health and Human Services obtained a patent in 1999 for the neuroprotective effects of cannabinoids (US patent 6630507).
The patent asserts that cannabis and its chemical compounds can protect brain cells in neurodegenerative diseases such as Parkinson’s disease, Alzheimer’s disease, and other forms of dementia.
Researchers investigating what role CBD plays in protecting the brain have also found that it can reduce brain damage caused by various traumas. In a study involving animal models of brain injury, researchers found that CBD increased the number of viable brain cells and reduced the number of injured brain cells by more than 50%.
The neuroprotective effects of CBD are related to its action on the CB2 receptor. CBD acts on CB2 receptors to produce anti-inflammatory responses in immune cells of the brain, thus minimizing the extent of damage caused by inflammation.
Oxidation also contributes to damage in brain tissue, and is partly responsible for the brain damage seen in conditions such as Alzheimer’s and Parkinson’s disease. Studies show that CBD acts on the CB2 receptor to reduce oxidative damage.
Damage to brain cells can cause additional harm by disrupting normal cellular functions. When brain cells are disrupted and begin firing repeatedly, the damage is known as excitotoxicity. CBD can help minimize this effect and maintain normal function in brain cells which would otherwise be susceptible to excitotoxicity.
Fights Seizures and Psychosis
One of the most fascinating effects of CBD involves its role in treating epilepsy. This effect has garnered widespread attention and has led to significant advancements in the treatment of seizure disorders.
The most prominent case of CBD being used to treat epilepsy is that of Charlotte Figi, a young girl suffering from Dravet syndrome. Dravet syndrome is a severe form of epilepsy in children, and at one point caused Charlotte to suffer from over 300 grand mal seizures a week. However, after starting treatment with CBD-rich oil, her seizures decreased drastically to only 2-3 per month.
CBD appears to exert its anticonvulsant effects by lowering the degree of excitation of brain cells which contribute to seizures. CBD also works to minimize excitotoxicity in epilepsy, expanding beyond its anti-convulsive effects and contributing to the protection of brain cells in the disorder.
It is thought that CBD decreases seizures in epilepsy in the same way that it regulates other chemicals in the brain. By enhancing the release of the inhibitory neurotransmitter GABA, CBD stops the brain mechanisms that contribute directly to seizures.
CBD also has significant antipsychotic properties. In a double-blind clinical study, researchers compared the effects of CBD to an antipsychotic drug called amisulpride in schizophrenic patients. They found that the antipsychotic effects of CBD were similar to those of amisulpride, but CBD was preferred by patients because it had less side effects.
The antipsychotic effects of CBD are related to its effect on anandamide. Specifically, higher levels of anandamide have been linked to a decrease in psychotic symptoms, and CBD is known to increase anandamide in the brain.
While the spectrum of conditions that CBD may treat is already very wide, the reality is researchers are only beginning to understand how this compound works in the brain and body.