Cannabis induced amotivational syndrome

Cannabis induced amotivational syndrome

By Dr. Fernando Caudevilla

One of the problems associated with cannabis consumption is known as the “amotivational syndrome”. According to some scientists, frequent consumption of cannabis can lead to a symptom picture that includes apathy, indifference towards things, loss of the spirit of improvement, lack of curiosity…

Ultimately, a lifestyle change that causes the ambitions and conventional motivations that push most people to disappear. There are many reasons to doubt of the existence of this syndrome. Throughout history and in relation to cannabis, references to something similar to this syndrome are unknown until the 1960s. It is during that decade that the first cases are described by American universities. This delay is amazing because the use of cannabis as a psychoactive is more than 8000 years old. No culture in history has ever kept record that people using cannabis for recreational or therapeutic purposes have suffered motivation issues.

Scientific data about this syndrome are scarce and old. Any search on any medical database for terms like “psychosis and cannabis” or “memory and cannabis” throws up hundreds of studies as a result. But a specific search for “amotivational syndrome” only obtains a few studies dating from the mid 70s and of a very poor scientific quality. Observations on this syndrome come from descriptive studies and several cases found amongst college and school population. These studies (Kolansky, 1971; McGlothin, 1968; Smith, 1968; Brill, 1974) showed a not very rigorous methodology design. As we know, cannabis can cause alterations in attention span and memory, intellectual capacities needed for an adequate academic or scholar performance. Use of cannabis is associated to worse school grades, absenteeism and negative attitudes towards school, but those results are better explained by the social context of the substance use, rather than being an effect of the substance itself (Lynskey, 2000; Fergusson 2003). It is obvious that frequent consumption of cannabis can have a significant negative impact over some teenagers’ school performance, but very rarely is school failure consequence of only one factor.

There is no doubt that many people can experience changes in their values or attitudes at the same time they start using cannabis. Lots of people start to smoke it during their teenage years or early youth, precisely a stage in life when most personality changes take place. Therefore, to have motivations or curiosities different to those of an adult can be considered more like a symptom of a normal development stage than a “cannabis associated illness”.

Another issue raised by this syndrome is its definition.  The diagnosis of a mental illness requires a series of universally accepted criteria. These requirements can be found in international classifications of psychiatry professional associations (DSM-IV,CIE-10). The amotivational syndrome does not appear in any of the aforementioned classifications and there has never been a description of what the specific requirements for its diagnosis are. 

This means that any professional or group of psychiatrists can choose the terms more to their liking to define the syndrome. We can find a relevant example of this in the Drug Addiction Guide written by Comunidad de Madrid’s Anti Drug Agency (2002), where the following definition can be read:

“Chronic use of marijuana has been associated to amotivational syndrome, characterized by apathy, loss of efficacy in developing complex works, early frustration, poor concentration and overestimation of self productivity. Such patients tend to be less compatible with their family and friends. They develop a less religious behavior, they act more independently and are less involved in conventional institutions. Their social customs are problematic and they show greater tolerance towards deviated conducts and are more frequently involved in actions of, at least, problematic nature”

We can guess what they mean by “less religious behavior” but  What do the authors mean by “tolerance towards deviated conducts” and “problematic actions”? Do marijuana smokers not perpetrate tax fraud like the rest of mortals? Or are they perhaps not happy when the national team wins? Or do they not go to the shopping centre on weekends? Jokes aside, this example should be useful to evaluate the scientific level of many so-called professionals that work in the drug field, as well as their tendency to pass their prejudices and moral premises as science.


McGlothlin WH, West LJ, The Marijuana Problem: An Overview, American Journal of Psychiatry, 125(3), pp. 370-378, 1968.

Smith DE, Acute and Chronic Toxicity in Marihuana, Journal of Psychedelic Drugs, 2, pp. 37-47, 1968.

Kolansky H. Moore W.T. “Effects of marihuana on. adolescente an young adults“. JAMA. Vol. 216, No. 3,. 1971.

Brill, N.Q., & Christie, R.L. (1974). Marihuana and psychosocial adjustment. _Archives of General Psychiatry, 31, 713-719.

Carlin AS and Post RD, Drug Use and Achievement, International Journal of the Addictions, 9(3), pp. 401-410, 1974.

Lynskey M, Hall W. The effects of adolescent cannabis use on educational attainment: a review. Addiction. 2000 Nov;95(11):1621-30.

Fergusson DM, Horwood LJ, Beautrais AL. Cannabis and educational achievement. Addiction. 2003 Dec;98(12):1681-92.


Este sitio web utiliza cookies para que usted tenga la mejor experiencia de usuario. Si continúa navegando está dando su consentimiento para la aceptación de las mencionadas cookies y la aceptación de nuestra política de cookies, pinche el enlace para mayor información

Aviso de cookies
¿Eres mayor de edad? Este sitio web requiere que tengas 18 años de edad o más. Verifique su edad para ver el contenido o haga clic en "No" para salir.