Key Takeaways:
Regular cannabis users are often portrayed with a negative, “lazy stoner” stereotype.
Previous research suggests there may be some truth to this, especially in young people, but more recent studies don’t support it.
The potential for negative long-term side effects from cannabis use appears to be greater for young people.
Movies, TV shows, and even the news media commonly portray cannabis users as “lazy stoners.” This depiction may be changing a bit, since cannabis use is now legal in many areas. But the stereotype persists. So, is there any truth to it?
Researchers have been studying this question for decades. But the data so far hasn’t been consistent. Now, though, there’s more research available on this issue than ever before. And, with increasing legalization, use, and funding for research, we can expect to learn even more in years to come.
Cannabis works in the brain by tapping into the body’s natural endocannabinoid system (ECS). The endocannabinoid system is a messaging system in the brain and body. There are ECS receptors throughout the brain and the body. When someone uses cannabis, the main ingredients — cannabidiol (CBD) and tetrahydrocannabinol (THC) –- attach to these receptors. This is what causes the short-term effects on mood, memory, and how you feel physically.
THC is the active ingredient responsible for the “high” (the mind-altering effects of cannabis). It influences your:
Thinking, concentration, learning, and memory
Planning and sense of time
Sense of pain
Bodily movements and coordination
Emotions, pleasure, and senses
THC also activates the reward system of the brain. This is important to the conversation about laziness or lack of motivation.
CBD, on the other hand, doesn’t have the same effects as THC on the brain. But it does have many reported health benefits, including helping with anxiety, sleep, and pain.
How cannabis makes you feel usually depends on the ratio of THC and CBD in the cannabis product you’re using.
There’s some variation in how regular, heavy, and chronic cannabis use are defined across research. Here are some typical definitions:
Regular use: being high 3 or more times a week
Heavy use: being high daily or several times a day
Chronic use: long-term heavy use over months and years
In the short-term, cannabis use can cause problems with memory, thinking clearly, concentration, and coordination. It can also cause feelings of panic, paranoia, and sadness — and even psychosis.
There’s evidence that long-term cannabis use (over months and years) can negatively affect your ability to think, learn, and save memories. This is especially true when cannabis use starts during adolescence. Small studies have shown that frequent cannabis users have impulse control problems and difficulty interpreting others’ expressions.
All of these things can impact your behavior and how you interact with the world around you.
The common stereotype is that a person who smokes cannabis is unmotivated, tired, and lazy. The term “cannabis amotivational syndrome” came about in the 1960s to describe this. Experts believed that regular, long-term cannabis use caused apathy, learning problems, and a lack of motivation.
There’s some evidence to support this idea. But there’s also data to suggest otherwise.
To understand this, researchers study the relationships between cannabis use and apathy and anhedonia:
Apathy is a loss of, or a drop in, motivation.
Anhedonia is a loss of interest in previously enjoyable activities.
Both apathy and anhedonia are related to how the brain processes rewards. And, as mentioned above, THC affects the reward system in the brain.
Past studies (from 2016) suggested that regular cannabis use is associated with anhedonia in adolescents and apathy in young adults. Experts believed heavy cannabis use could lead to lack of motivation in daily or required tasks. The reason given for this was that cannabis use becomes the primary motivator.
That said, recent research didn’t find these links in teens or adults when compared with controls (people who don’t use cannabis).
Another recent study agreed. It looked at 260 regular cannabis users (using it 3 or more times per week). The participants reported feeling more impulsive while high. But their overall motivation or willpower wasn’t affected by regular use or regular heavy use of cannabis.
It’s increasingly clear among experts that the relationship between cannabis use and motivation and behavior is complex.
Not only that, but the studies are difficult to interpret. For example, observational studies can’t control for variables — other factors that may also influence behavior but aren’t related to cannabis use. And many studies rely on people self-reporting their cannabis use.
In other words, there’s a lot of room for error and bias. Without better evidence, it’s very hard to prove that cannabis use causes laziness or a lack of motivation.
There are few studies on workplace performance and cannabis use. But many studies suggest that the frequency of cannabis use is linked with worse high school and college grades and completion rates. This is probably not surprising, since cannabis is known to impair the following:
Attention
Coordination
Cognitive functioning
Memory
Learning ability
Cannabis with high THC content is the most potent. (That’s anything with a THC concentration higher than 20%.) These products can impair your memory and motivation while you’re high. But issues with learning may last even after the high ends. Without the ability to concentrate and focus, performing well in a work or school setting becomes a real challenge.
There are links between regular cannabis use and several mental health conditions. But it’s not easy to determine cause and effect. That means it’s not clear if cannabis use causes mental health problems — or if people with undiagnosed and untreated mental health problems turn to cannabis for relief from their symptoms.
Previously, experts thought that chronic cannabis use was linked to an increased risk of psychosis. But recent research findings don’t support this. Similarly, there may be a link between cannabis use and depression. But this could be explained by people with depression being more likely to use cannabis.
That said, cannabis use disorder and dependence are more likely in people with mood disorders, including major depressive disorder. So, the relationship between cannabis use and mental health changes is not clear-cut.
It’s worth noting that the negative effects of cannabis use seem to be more concerning for younger people. For example, regular cannabis use in teens is linked to:
Altered brain networking
Problems with cognition (thinking)
Addiction later in life
As noted, cannabis use has plenty of consequences and potential negative effects. But there are short-term benefits of cannabis use. People use cannabis to experience:
Feeling calm and relaxed
Sensing things around you in a different way
A sense that time is speeding up or slowing down
Stress relief
Some people also seek out cannabis for its medical benefits. Experts are either studying or recommending the use of cannabis or cannabinoids to treat health concerns like:
Multiple sclerosis (MS)
In many cases, the long-term benefits of using cannabis for medical uses require further research.
Cannabis can trigger unwanted side effects in addition to the desired ones. Some of the most common undesirable, short-term effects of THC include:
Feeling anxious
Fast heart rate
Dizziness
Paranoia, distrust, and delusional thinking
Hallucinations, where you see, hear, smell, taste, or feel things that aren’t really there
The risk of these side effects increases as the THC dosage goes up. Regular use of high-THC cannabis products can also lead to longer-lasting issues. These include:
Cannabis hyperemesis syndrome (increased vomiting and stomach pain)
An increased risk of cardiovascular disease
Dependence (needing to keep using cannabis)
Researchers continue to look into the long-term effects on the brain from regular cannabis use.
It’s important to note that THC content has increased over the last several decades in many countries, including the U.S. And higher content is linked with greater harm.
Cannabis has a reputation for causing laziness and lack of motivation. Some research supports that — but not all of it. What’s clear is that the developing brains of teens and young people seem to be most open to the harmful, long-term effects of cannabis. Time (and research) will tell us more about these long-term effects.
If you or someone you know struggles with substance use or mental health, help is available. Call SAMHSA’s National Helpline at 1-800-662-HELP (4357) to learn about resources in your area. For immediate assistance, call the National Suicide Prevention Lifeline at 988, or text “HOME” to 741-741 to reach the Crisis Text Line.
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