Marijuana memory effects

Dornbush RL (1974) Marijuana and memory effects of smoking on storage. Trans N Y Acad Sci 36 94-100... 

Marijuana s effects are not limited to the hippocampus, however. Besides making a person high and interfering with memory, marijuana can cause some people to experience uncontrollable laughter one minute and paranoia the next. These effects are due to cannabinoid receptors in another part of the brain, the limbic system, where emotions are produced. 

This chapter summarizes the methods and results of studies in which the author examined the acute or chronic effects of marijuana on human associative processes and memory. Eleven tests used to assess marijuana s effects on associative processes, semantic memory, and episodic memory are described. 

Key Words A -tetrahydrocannabinol acute effects associative processes chronic effects constrained associations episodic memory free associations free recall human learning marijuana memory paired-associate learning reaction time recall retrieval semantic memory THC. 

Block RI and Wittenborn JR (1986). Marijuana effects on the speed of memory retrieval in the letter-matching task. International Journal of Addictions, 21, 281-285. 

Heishman SJ, Arasteh K and Stitzer ML (1997). Comparative effects of alcohol and marijuana on mood, memory, and performance. Pharmacology, Biochemistry and Behaviour, 58, 93-101. 

Parley CF, Tinklenberg JR, Roth WT, Vernon S, Kopell BS. (1977). Marijuana effects on long-term memory assessment and retrieval. Psychopharmacology (Berlin). May 9 52(3) 239-41. 

Hooker WD, Jones RT. (1987). Increased susceptibility to memory intrusions and the Stroop interference effect during acute marijuana intoxication. Psychopharmacology (Berlin). 91(1) 20-24. 

Recently, two studies have examined the residual effects of long-term marijuana use.224,225 In both studies, marijuana smokers were abstinent for 28 days during which time a battery of neuropsychological tests was repeatedly administered. Daily, chronic smokers were compared to less frequent smokers. Bolla et al.224 reported that daily smokers were impaired on tests of memory, executive functioning, and psychomotor skills after 28 days of marijuana abstinence. In contrast,... 

A9-Tetrahydrocannabinol (A9-THC) is considered to be the predominant compound in preparations of C. sativa (marijuana, hashish, bhang) that is responsible for the central nervous system effects in humans. The recognized central nervous system responses to these preparations include alterations in cognition and memory, euphoria, and sedation. Potential therapeutic applications of cannabis preparations that are of either historical or contemporary interest include analgesia, attenuation of the nausea and vomiting of cancer chemotherapy, appetite stimulation, decreased intestinal motility of diarrhea, decreased bronchial constriction of asthma, decreased intraocular pressure of glaucoma, antirheumatic and antipyretic actions, and treatment of convulsant disorders. These effects have been reviewed recently (Howlett, 1995). 

The short-term effects of marijuana use include an impairment of short-term memory and learning. A survey of 12- to 17-year-old students found a correlation between past-year marijuana use and lower grade averages. However, this survey did not take into consideration possible pre-existing behavioral problems that may have also influenced grade averages. 

Consequences of the short-term effects of marijuana can greatly influence a teen s future life. Short-term acute effects describe a condition that is temporary and short-lived longterm chronic effects are cumulative and can last a lifetime. Many studies document the acute and chronic health consequences of smoking marijuana. For instance, there are consistent reports that marijuana temporarily impairs short-term memory and learning. This is confirmed by users of marijuana outside the... 

While the effects of marijuana on health are still being debated, a number of facts seem clear. The effects of marijuana differ from individual to individual. Regularly observed physical effects include a substantial increase in the heart rate, bloodshot eyes, dry mouth and throat, and increased appetite. Short-term memory is reduced, but ideas flow rapidly and the smoker may feel high or hilarious. The most common response is a calm, mildly euphoric state in which time seems to slow down. A song on a compact disc that lasts about two minutes may seem to take twenty minutes. Sensitivity to touch, sights, and sound are enhanced, so the words of the song that once seemed jumbled are now clear—or at least, they seem clear. 

While many things about marijuana remain controversial, even the most liberal supporters consider its use by adolescents harmful. It is possible that the increased popularity of marijuana is cyclical, and that this drug will become less popular as new information about its effects on the body is discovered. More is known about marijuana today than was known when many parents smoked it as teens. Some of the most important effects are noted by Joseph Califano, president of the National Center of Addiction and Substance Abuse at Columbia University Marijuana can savage short-term memory and adversely affect motor skills. It inhibits social and emotional development at the time when such skills and development are most critical for teens. There are very real dangers attached to marijuana s frequent use. 

Smith, A. M., Fried, P. A, Hogan, M. J., and Cameron, I. (2006). Effects of prenatal marijuana on visuospatial working memory An fMRI study in young adults. Neurotoxicol. Teratol. 28, 286-295. 

The panel did find short-term effects on "immediate memory, "oral communication and "learning, and said that it sometimes "may trigger temporary confusion and delirium. Noting that "about a quarter of the entire [U.S.] population has tried it at least once, Reiman reported the study group s recommendations (1) more work to produce marijuana derivatives with increased therapeutic action and less side effects, (2) a high-priority national effort to find out more about this drug, and (3) the decriminalization of penalties for personal marijuana use. 

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