A new study carried out by University College London (UCL) has found that marijuana use reduces a person’s short-term motivation to work for money.
Despite popular thought being in line with these results, this is the first research study to reliably demonstrate the short-term effects of cannabis on motivation. It was found that smoking even just a single ‘joint’ can have a negative effect.
The study comprised of a group of cannabis users who were split into two. Both groups were given a vapour – one which contained cannabis and another which contained a placebo. Both groups were then given the choice of carrying out a relatively easy task or a more difficult one. The easy task consisted of tapping the spacebar on a computer keyboard 30 times in seven seconds and the harder instruction required 100 taps in 21 seconds.
The easy task paid out 50p whilst the harder task paid between 80p and £2. Despite being presented with the opportunity to earn more money, those who were high on cannabis were still significantly less likely to choose the high-effort option.
In a second test, the researchers compared people who were ‘cannabis dependent.’ None of the participants were allowed to consume alcohol or drugs (apart from coffee and cigarettes) for 12 hours prior to the study. This time, the groups showed no difference in their willingness to tap the spacebar which supports the idea that marijuana use has a negative impact on our productivity levels.
The growth of cannabis use
The results of the study coincide with figures about cannabis use in the US. The numbers show that there has been a significant rise in the number of Americans who are using cannabis. In 2002, 21.9 million people across the country admitted to using the drug whereas by 2014, this had risen to 31.9 million.
The 2015 European School Survey Project on Alcohol and other Drugs (ESPAD) report also found that while cigarette and alcohol use amongst 15 and 16-year-olds is declining across Europe, the number of cannabis users is growing. There was found to be large differences in cannabis use amongst the different European countries but upward trends were particularly noted in Bulgaria, Greece, Poland and Romania.
It is suspected that one of the reasons for this could be because marijuana is far more readily available than other drugs such as ecstasy or cocaine. Despite the fact that the decriminalisation of marijuana is a much debated topic, interestingly, the report found no correlation between anti-drugs legislation and cannabis use.
What are the effects of cannabis on the body?
A new study published in The Lancet Psychiatry gives another interesting insight into what could be causing the rise in the number of cannabis smokers. The research found that despite the fact that the drug is still illegal in many countries, people perceive it to be less harmful than they used to.
There are a number of other ways that marijuana has an effect on the body, including:
- Brain – cannabis has a major effect on the way that our brains process information. It contains at least 60 different types of chemical compounds which act on receptors throughout the brain. Having too much can therefore make us feel anxious, paranoid or panicked. Continued use can lead to addiction
- Heart – just after you’ve taken your first puff, your heart rate speeds up by 20 to 50 beats per minute. This can continue for up to three hours after smoking
- Eyes – red eyes are one of the most common and obvious signs of cannabis use. In more serious cases, it can also lead to hallucinations because the drug affects parts of the brain which process what we see
- Stomach – cannabis flips a switch in the brain which is normally responsible for controlling our appetite, and this is why people often get so hungry when they smoke it
- Long-term effects – chronic cannabis users tend to have smaller grey matter volumes in the orbitofrontal cortex – this is the part of the brain linked to addiction