Marijuana attentional abilities

Other studies of heavy marijuana users show that the drug inhibits the ability to focus attention, learn new information, and solve problems as long as two days after taking it. This most likely occurs because THC changes the way the brain processes new information THC stifles neural activity in the hippocampus by suppressing acetylcholine release. Long-term use can cause changes in users brains that are similar to those caused by other controlled substances. 

A 50-year-old man with hereditary osteo-onychodys-plasia had smoked marijuana since 1974 to alleviate muscle spasms and pain (current use 7 g/day of 3.75% THC). He had mild-to-moderate impairment of attention and concentration and reduced ability to acquire new verbal material. He scored poorly on the California Verbal Learning Test (CVLT), a measure of short-term memory recall, and had difficulty with motor tasks. 

Acute physical and psychological effects. Marijuana intoxication has an adverse effect on attention span, short-term memory, and psychomotor performance. Anxiety and panic attacks can occur, primarily in new users who are not familiar with marijuanas eflFects. At very high doses, some people experience delusions and hallucinations. There are no cases of fatal marijuana poisoning and humans are very unfikely to be able to ingest a fatal dose. The eflFect of marijuana intoxication impairs motor and cognitive abilities necessary to safely drive a car or operate machinery. The extent to which marijuana is involved in auto accidents is unclear. Many motorists intoxicated with marijuana drive more slowly and carefully and take fewer risks. However, there is an increased risk of accidents after using marijuana, but marijuana alone does not appear to contribute a great deal to accidents. Marijuana in combination with alcohol does. 

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