Cannabinoids, being the active ingredients in cannabis, possess a wide array of physiological effects that include acting on the brain and memory. The two most prominent cannabinoids, delta-9-tetrahydrocannabinol and cannabidiol, are receiving ever greater appreciation for their potential use in therapy, even if there is a very continuous concern regarding their effects on memory formation. Some research indicates that some types of memory may be adversely affected by cannabinoids, while others seem to indicate that memory loss conditions may be treated with the help of cannabinoids.
In order to determine when and how cannabinoid treatment will affect memory, it is necessary to learn about the Endocannabinoid system (ECS) and, more importantly, the difference between THC and CBD and what those differences lead to in the short and long term.
How Does the Endocannabinoid System Relate to Memory Enhancement?
The endocannabinoid system (ECS) consists of several components and acts in the regulation processes of mood, pain, appetite, memory, etc. It comprises cannabinoid receptors CB1 and CB2, orthosteric and allosteric receptors, endogenous cannabinoids and enzymes. The ECS is located within the deepest memory centers, such as the hippocampus — the region responsible for new memory constructions. To the brain’s CB1 receptors, cannabinoids, including THC and CBD, bind. The ECS disruption by cannabis use changes how memory is formed and retrieved.
What Are the Effects of Marijuana Use on Memory?
Tetrahydrocannabinol – the major psychoactive component in cannabis, is mostly believed to work by inhibiting short-term memory. THC interacts with areas in the brain that are responsible for the formation of memories, including the hippocampus and prefrontal cortex, via binding to the CB1 receptors, thus inhibiting the normal cycle of information encoding and retrieval.
- Short-term memory suppression: The most remarkable effect that results from phytocannabinoid consumption is that it causes impairment in creating new memories, which means that new information cannot be learned and even recent events may not be remembered. This occurrence is very short and only lasts as long as cannabis is in the system, and such memory impairment decreases with time because the substance is broken down. Further, these memory impairments in cognition function are likely more pronounced in patients who use more THC, in which recent use of cannabis is associated with changes in attention and learning.
- Long-term consequences of chronic use: Long-term episodes of high tetrahydrocannabinol use, including addiction, have been studied by several scientists. These researchers have found that extended periods of cannabis use may lead to structural changes within the brain, mainly affecting the hippocampus and possibly resulting in permanent loss of cognitive function. It is, however, very alarming, more so for adolescents, whose brains are still growing, as some effects of cannabis on the memory and learning processes could make them more susceptible than adults' brains.
How Does CBD Oil Affect Memory?
Cannabidiol differs from THC in that it is not psychoactive. It does not cause the user to experience any feeling of being ‘stoned’ or euphoric. In fact, several studies have found that CBD is effective in protecting against damage caused by THC, the component of marijuana that causes the “high” and which also has memory-impairing effects.
- Protective action against memory degradation: Most recent studies have reported investigations into the use of CBD as a potential remedy for various aspects of age-related cognitive decline and even the promotion of the formation of new cells in the hippocampus, a process called neurogenesis. As a result, this prompted an intense curiosity about the potential of CBD in preventing the development of diseases associated with a decline in the functioning of memory centers, such as Alzheimer’s disease and other dementias.
- CBD and THC interaction: Interestingly, it has also been discussed that the effects of CBD, when combined with THC, can help alleviate some of the memory-impairing effects of THC. CBD has been found to play a role in the interaction of THC and CB1 receptors and possibly decrease the level of impairment in short-term memory. This indicates that cannabis products that have a higher ratio of CBD as compared to THC would be more effective with respect to the reduction of adverse cognitive effects that are often related to high THC strains.
What is the Relation Between Cannabinoids and Memory Disorders?
Besides the usual effects of marijuana on memory, marijuana, as well as cannabinoids, has been ineffective in diseases of memory dysfunction such as dementia, Alzheimer’s disease, Parkinson’s disease, traumatic brain injury (TBI) etc. It is well-known that these diseases involve some memory and cognitive degeneration, and the available evidence indicates that cannabinoids may be beneficial in some neurodegenerative conditions.
- Alzheimer’s disease: Alzheimer's disease is a type of dementia and a disease of the nervous system characterized by progressive loss of memory. There are studies that show that prolonging Alzheimer's disease can be mediated with the use of cannabinoids, mostly CBD, by moderating inflammation, oxidative stress, and limiting the aggregation of amyloid plaques which is typical in this disorder. While more research is needed, these early findings enable the conclusion of cannabinoids as protective substances for memory and the overall health of the brain.
- Traumatic Brain Injury: After a head injury, inflammation and oxidative stress can further degrade cognitive processes, including memory. Cannabinoids were at least partially successful at limiting these adverse effects, facilitating recovery from injury, and potentially improving cognition in TBI patients. It has been shown that cannabinoids can help in the preservation of memory after injury, due to the reduction of neuroinflammatory processes and the stimulation of creation of new neurons.
- Post-Traumatic Stress Disorder: The most prominent symptoms of PTSD are generally centered on highly intrusive memories of a traumatic event or flashbacks, which suggest an abnormality in memory processing. Cannabinoids, particularly CBD, have garnered interest as a prospective clinical modality to treat PTSD because of their usefulness in modulating fear emotions and increasing defense from anxiety. There is some evidence that suggests cannabinoids could assist patients in dealing with these memories to promote less distressing and frequent recollections, which would be beneficial.
How Do the Effects on Short-Term and Long-term Memory Compare?
Different cannabinoid compounds could manage different forms of memory in better way than others. Short term remembrance involves the retention and retrieval of information for short durations typically between minutes to hours, while long-term memory involves the retention of information for long periods of up to days, months, and years.
- Short-term memory effects: There are several temporary short-term effects when it comes to cannabis, one of them being short-term memory loss. This is when recalling events immediately is hampered, as well as attention and learning of new events. These effects are most of the time on a short-term basis, especially for light marijuana users of cannabis within which moderate THC content is found. However, high-THC regular cannabis users may develop memory deficits, which may be relatively long-lasting.
- Long-term memory effects: Even though chronic use of marijuana is accompanied by side effects, chronic exposure, particularly during younger ages or high levels of THC consumption, has been associated with adverse impacts on long-term memories. There has been evidence that shows a person using cannabis has long-term effects on the structure of the brain, especially the regions related to memory storage, but these effects may lift after a period of abstinence from cannabis.
What Factors Influence Cannabinoid Effects on Memory
Several factors influence how cannabinoids are thought to modify memory, including:
- Dosage: It is expected that higher doses of THC will cause more short-term memory loss than lower doses.
- Frequency of use: People who use cannabis occasionally would have less likelihood of being mentally impaired in the future compared to those who are severe users of the substance. On the other hand, chronic use or excessive usage can lead to irreversible cognitive changes.
- Age and brain development: Young people are likely to be more vulnerable to the memory-impairing effect of cannabis.
- Individual differences: People’s genetic constitutions, health conditions, and behavioral lifestyles all generate variations in the way you respond to cannabinoids and memory. For example, while some may have difficulties recovering from the adverse effect of cannabis on memory, others will take little notice of the impact.
Conclusion
The effects of cannabis on memory are dynamic, with most literature indicating a deleterious effect of THC on memory formation while CBD is healing for memory. This can be attributed to the dose of THC. However, CBD facilitates the ability of the brain to withstand damages caused or emanating from Alzheimer’s disease and PTSD, an aspect that is very encouraging.