memory and marijuana

Cannabis and the Brain: How THC Affects Memory, Attention, and Emotion

March 24, 2023

It's no secret that the cannabis plant can have significant effects on people's minds and bodies; people have been using this plant for thousands of years, and scientific research has demonstrated how it can affect things like pain, inflammation, stress levels, sensations of nausea, appetite, energy levels, and so on.

While the plant can offer an array of medical benefits that make it a useful treatment option for those with various conditions, like cancer, epilepsy, and chronic pain problems, studies also show that one cannabinoid in particular, THC, can have quite serious and powerful short and long-term effects on the brain.

THC and Memory

It's normal for a person's memory to degrade as they get older, and many elderly people may struggle to remember things as clearly or easily as they once did. However, scientific studies show that regular and repeated use of cannabis products containing tetrahydrocannabinol, or THC, may speed up this process.

How THC Affects Short-Term Memory

Many people who smoke cannabis that contains high levels of THC report that they tend to feel a little forgetful for a while afterward or that their brains feel "slow" when it comes to making decisions or thinking of things. 

From a scientific perspective, this is because THC attaches to certain cannabinoid receptors in key parts of the brain that are connected to memory, like the hippocampus, amygdala, and cerebral cortex, disrupting the way it works.

How THC Affects Long-Term Memory

Studies into THC’s effects on long-term memory aren’t quite as clear, as there are lots of factors that might affect a person’s memory over time, and it’s hard to say how big of an influence THC truly has. 

However, animal studies have shown that subjects exposed to THC at an early stage of life tend to show more cognitive weaknesses and memory problems when they're older. It's believed that this might be because THC hastens the age-related loss of nerve and brain cells that help us remember things.

The Impact of Chronic THC Use on Memory

Research indicates that individuals who start using cannabis at a young age and continue the habit for an extended period of time are more likely to experience cognitive issues in their later years, such as memory difficulties.

In other words, people who use a lot of cannabis will generally become more forgetful as they get older, due to the way in which THC affects the hippocampus. However, more studies are required to provide conclusive evidence.

THC and Attention:  How THC Affects Attention and Focus

People who consume THC may also find that they struggle to concentrate or maintain their attention levels on something for an extended period of time. Studies have shown that regular marijuana use can produce similar symptoms to attention deficit hyperactivity disorder. 

Again, scientific evidence on this subject is limited, but it is believed that as THC interferes with certain processes in the brain and attaches to key neuron receptors, it can make a person less focused, impairing their processing speeds and learning functions.

THC and Emotion:  How THC Affects Mood

THC can also have some notable impacts on a person's mood and emotions. Many people associate THC with cannabis' famous 'high' and feelings of happiness and euphoria, and in the short-term, it can make people feel very relaxed and happy.

Cannabis, and THC in particular, can make people feel more talkative, sociable, and confident, too. However, there's also a risk of negative emotions, such as paranoia, depression, and panic, and in the long term, users who consume excessive amounts may be at a greater risk of psychosis and certain mental health disorders.

Brain Mechanisms of THC's Effects

It’s clear that THC can have some serious and long-lasting impacts on the brain, but how does it actually work? In this section, we’ll look at how THC takes effect and makes its mark on the brain.

How THC Interacts with the Endocannabinoid System

The main way in which THC and other cannabinoids work are by interacting with the endocannabinoid system, or ECS. The endocannabinoid system (ECS) is an intricate cell-signaling network in the human body that regulates various physiological processes and sensations, including pain perception, mood, appetite, and fatigue.

THC is able to bind with receptors, known as CB1 and CB2 receptors, within the ECS. These receptors are located primarily in the brain, and once THC binds with them, it can influence or trigger the ECS to create certain changes throughout the body. This is how THC can help with things like pain relief or making people feel hungrier.

The Impact of THC on Neurotransmitters and Brain Regions Associated With Memory, Attention, and Emotion

Studies show that THC can have a direct effect on neurotransmitters, chemical messengers that deliver signals between nerve cells. Specifically, it can stimulate neurons to release dopamine, which is well-known as the brain chemical that can help people feel happier and more relaxed. 

In addition, by binding with receptors in key regions of the brain, like the hippocampus and cerebral cortex, THC can have both short and long-term effects on cognitive processes, affecting people’s memory levels, attention spans, and emotions. 

Further research is necessary to fully understand the mechanisms involved, but it is evident that THC interacts with receptors in these brain regions and alters their functioning. With repeated and high-dose THC usage, it is logical to assume that long-term alterations in these brain regions' activity will occur.


As cannabis products become increasingly prevalent and cannabis consumption rises in many regions globally, it is crucial for users to recognize the potential long-term implications of excessive or repeated use. While THC and other cannabis components offer various advantages, they also present risks that should not be overlooked.

Author Bio

Rebecca Akers is an enthusiastic and creative writer at THC Design. Her main goal is to spread information about growing cannabis and its health benefits. After studying communications and creative writing, and with years of background working with cannabis businesses, Rebecca's primary goal is to educate and share.