Psychological Effects of Weed: 3 Myths, Motivation and the Psychosis Risk

Yes, smoking weed can affect you psychologically: THC temporarily changes mood, memory and motivation, and heavy, long-term use of high-THC cannabis is linked to a higher risk of dependence, anxiety and psychotic symptoms, especially in young people. People have smoked cannabis for centuries, for medicine and for fun, but today its effects on the mind sit at the center of a global debate.

When you smoke weed, THC enters the bloodstream fast and reaches the brain, where it binds to cannabinoid receptors. Those receptors are part of the endocannabinoid system, which plays a key role in regulating mood, appetite, memory and sleep.

THC's interaction with these receptors can temporarily change those functions, and that's what produces the immediate effects of getting high.

Some people find those effects enjoyable; others find them unsettling, especially first-timers or anyone who overdoes it.

Cannabis and mental health: 3 weed myths to bust

Weed comes wrapped in myths and misunderstandings. Separating fact from fiction is essential if you want to make informed decisions about using it. Here are three of the most common myths, and what's actually true.

Myth 1: "Weed doesn't affect your mental health"

FALSE. The idea that weed has no impact on mental health is wrong. Long-term use of high-THC cannabis (THC being the main active compound in weed) can significantly raise the odds of developing an addiction.

On top of that, a study published in The Lancet found that people who smoke weed regularly are more likely to develop cannabis-induced psychosis and to have recurring depressive episodes.

Myth 2: "Smoking weed regularly reduces anxiety"

FALSE. This myth comes from mixing up cannabis compounds. The plant's two headline ingredients are CBD and THC. CBD is extracted to help with certain physical and mental health issues, like anxiety, and it doesn't get you high.

THC, on the other hand, the compound in recreational weed, is what produces the euphoric, feel-good high, but it isn't an anxiety treatment. In fact, in some cases THC can make anxiety symptoms worse instead of better.

Myth 3: "Weed is safe because it isn't addictive"

FALSE. Plenty of people think of weed as harmless, but long-term use can lead to addiction. Dependence may take longer to develop than with drugs like cocaine or meth, but cannabis use disorder is real and it does damage.

People who become dependent on weed may have trouble remembering or learning new things, and can come to rely on it for their emotional and psychological well-being.

That dependence can cause problems in relationships and daily life, as people drift away from family, friends and the things they used to enjoy.

The takeaway

Busting these myths is key to understanding how weed really affects mental and physical health. Recognizing that cannabis can affect your mental health, isn't a miracle cure for anxiety and can be addictive is essential for making informed choices about using it.

As research on this plant keeps moving forward, it pays to stay up to date and question the information floating around.

Psychological effects of weed: how it affects your mind

How cannabis affects the human mind is a topic of growing interest and concern. Recent research published in The Journal of Psychopharmacology, Neuropsychopharmacology and the International Journal of Neuropsychopharmacology shows how its use can influence a range of cognitive and psychological processes.

How many people use cannabis?

According to the United Nations Office on Drugs and Crime (UNODC), around 192 million people worldwide between the ages of 15 and 64 used cannabis recreationally, based on 2018 data. About 35% of them were between 18 and 25, so young adults make up a big share of users.

Since young people's brains are still developing, they may be especially vulnerable to cannabis's long-term effects on the brain.

The role of THC, the main psychoactive compound in cannabis plants

Tetrahydrocannabinol (THC) is the main psychoactive ingredient in cannabis. It interacts with the brain's endocannabinoid system, which has specific receptors that respond to cannabis compounds.

These receptors are especially abundant in the prefrontal and limbic areas of the brain, regions that are crucial for regulating reward and motivation.

How THC affects brain chemistry

Cannabinoid receptors regulate signaling for several major neurotransmitters, including dopamine, gamma-aminobutyric acid (GABA) and glutamate.

Dopamine

Dopamine is a key neurotransmitter involved in motivation, reward and learning. THC's interaction with cannabinoid receptors can change how dopamine is released and regulated, which can affect motivation and the ability to feel pleasure.

Gamma-aminobutyric acid (GABA)

GABA is an inhibitory neurotransmitter that plays a crucial role in regulating neuron excitability and anxiety. THC can influence GABA signaling, which can lead to changes in anxiety levels and emotional regulation.

Glutamate

Glutamate is the brain's main excitatory neurotransmitter and is involved in cognitive processes like memory and learning. THC can disrupt glutamate signaling, which could have negative effects on cognitive function.

Cannabis and mental health: what the research shows

Cannabis doesn't just affect how we think, but also how we feel and behave. Here's a look at recent research on its effects on motivation and the brain circuits behind it.

Does weed kill your motivation?

Research suggests cannabis can influence the brain's reward and motivation circuits. Those changes can affect how we perform at everyday things like work or school, dampening motivation and the sense of reward.

One recent study used a brain-imaging task in which participants, while in an MRI scanner, had to respond to blue and orange squares. The orange squares came with a cash reward if the participant responded correctly.

This setup let researchers study how the brain responds to rewards, zeroing in on the ventral striatum, a key region in the brain's reward system.

The results showed subtle effects of cannabis on the ventral striatum, even though the participants were only moderate users. The effects are expected to be more pronounced in chronic users.

Mental effects of weed

Cannabis use is also linked to mental health problems, including anhedonia (the inability to feel pleasure) in teens, a problem that got worse during the COVID-19 lockdowns.

Cannabis-induced psychosis

Cannabis can be a risk factor for psychotic episodes and schizophrenia. One study found that moderate weed use increases the risk of psychotic symptoms in young people, especially those with a genetic predisposition to psychosis.

In a study of 2,437 teens and young adults (ages 14–24), cannabis users with no predisposition to psychosis saw their risk of psychotic symptoms rise from 15% to 21%, while among those with a predisposition it jumped from 25% to 51%.

It's not fully understood why cannabis is linked to psychotic episodes, but dopamine and glutamate are thought to play important roles in the neurobiology behind them.

Another study of 780 teens linked cannabis use and psychotic experiences to a brain region called the uncus, part of the parahippocampal gyrus (involved in memory) and close to the brain's smell-processing areas, a spot packed with cannabinoid receptors.

What shapes the psychological effects of cannabis?

The cognitive and psychological effects of cannabis depend on several factors, including dose (how often, for how long and how potent), sex, genetic vulnerabilities and the age you started. A key question is whether these effects are temporary or permanent. A review summarizing multiple studies suggests that with moderate use, the effects may fade after periods of abstinence.