Title: The Science Behind Marijuana and Motivation - Leaf Science
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Content: Some studies show that marijuana can lower motivation, while others find no difference at all. The belief that marijuana reduces motivation can be traced back to the 1960s and 70s. During this time, North America saw an increase in cannabis use, and many early studies claimed that using marijuana could lead to chronic laziness. Amotivational Syndrome
In 1972, scientists came up with the term amotivational syndrome to describe the loss of drive to work, socialize, and attain success in life commonly seen in marijuana users. Marijuana users were described as apathetic, lethargic, and disengaged. This theory has since been challenged. Today, there is little evidence to support the idea that marijuana causes amotivational syndrome. What evidence we do have is poor-quality: observational, and with small sample sizes. For example, Lynskey and Hall cite several studies which find that marijuana use is correlated with lower educational attainment, such as lower grades, higher rates of skipping class, and less satisfaction with school.