Cannabis reduces short-term motivation in humans read more at here www.spinonews.com/index.php/item/765-cannabis-reduces-short-term-motivation-in-humans

A study from UCL finds, Smoking the equivalent of a single spliff of cannabis makes people less willing to work for money while ‘high’.

The research demonstrates the short-term effects of cannabis on motivation in humans. The researchers also tested motivation in people who were addicted to cannabis but not high during the test, and found that their motivation levels were no different to volunteers in the control group.

“Although cannabis is commonly thought to reduce motivation, this is the first time it has been reliably tested and quantified using an appropriate sample size and methodology,” says lead author Dr. Will Lawn.

Long-term cannabis users might also have problems with motivation even when they are not high. However, we compared people dependent on cannabis to similar controls, when neither group was intoxicated, and did not find a difference in motivation. It may not result in residual motivation problems when people stop using it.

In the research 57 volunteers were involved, which consisted of two separate studies. The first involved 17 adult volunteers who all used cannabis occasionally. After, they completed a task designed to measure their motivation for earning money. This was a real-life task as the volunteers were given money they had earned at the end of the experiment.

In each trial of the task, volunteers could choose whether to complete low- or high-effort tasks to win varying sums of money.

Researchers found that people on cannabis were significantly less likely to choose the high-effort option. On average, volunteers on placebo chose the high-effort option 50% of the time for a £2 reward, whereas volunteers on cannabis only chose the high-effort option 42% of the time.

In the second study, 20 people addicted to cannabis were matched with 20 control participants who reported the same levels of non-cannabis drug use. They were then asked to perform the same motivation task as participants in the first study.

The results showed that cannabis-dependent volunteers were no less motivated than the control group.

 

The first study was funded by Drug Science and the second study was funded by UCL and the Biotechnology and Biological Sciences Research Council.