Related Experiment Videos
Marijuana and memory impairment: effect on free recall and recognition memory
Pharmacology, Biochemistry, and Behavior
|August 1, 1977
Summary
Marijuana significantly impairs immediate and final word recall but has minimal effect on recognition memory. Long-term retention and acquisition rates remain unaffected by delta-9-THC.
Area of Science:
- Neuroscience
- Psychopharmacology
- Cognitive Psychology
Background:
- Understanding the cognitive effects of cannabis, particularly delta-9-tetrahydrocannabinol (THC), is crucial.
- Memory functions, including recall and recognition, are key areas of investigation regarding THC's impact.
Purpose of the Study:
- To investigate the specific effects of a single marijuana dose on various memory processes.
- To determine how delta-9-THC influences immediate recall, final recall, and recognition memory.
Main Methods:
- Two groups of 17 male volunteers received a marijuana cigarette with 14 mg delta-9-THC.
- Participants were tested on immediate free recall, final free recall, and recognition memory using word lists (repeated and nonrepeated).
Main Results:
- Marijuana significantly reduced immediate and final free recall performance.
- Recognition memory was only slightly affected, indicating preserved ability to identify previously seen words.
- Acquisition rates for repeated words and long-term retention were not significantly influenced by marijuana.
- Serial position curves showed some drug effects on the recency portion, and both internal and external intrusions increased.
Conclusions:
- Delta-9-THC primarily impairs the ability to actively retrieve information (recall) rather than recognize it.
- While immediate retrieval and intrusion rates are affected, the encoding and long-term storage of information appear relatively preserved.
- Findings contribute to understanding the nuanced effects of cannabis on memory consolidation and retrieval processes.