It is uncertain whether frequent marijuana use adversely affects human brain function. Using positron emission tomography (PET), memory-related regional cerebral blood flow was compared in frequent marijuana users and nonusing control subjects after 26+ h of monitored abstention. Memory-related blood flow in marijuana users, relative to control subjects, showed decreases in prefrontal cortex, increases in memory-relevant regions of cerebellum, and altered lateralization in hippocampus. Marijuana users differed most in brain activity related to episodic memory encoding. In learning a word list to criterion over multiple trials, marijuana users, relative to control subjects, required means of 2.7 more presentations during initial learning and 3.1 more presentations during subsequent relearning. In single-trial recall, marijuana users appeared to rely more on short-term memory, recalling 23% more than control subjects from the end of a list, but 19% less from the middle. These findings indicate altered memory-related brain function in marijuana users.
This research output has an Altmetric Attention Score of 33. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 29 November 2019.
All research outputs
#1,554,029
of 34,518,147 outputs
Outputs from Pharmacology, Biochemistry & Behavior
#99
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Outputs of similar age
#1,687
of 178,195 outputs
Outputs of similar age from Pharmacology, Biochemistry & Behavior
#4
of 50 outputs
Altmetric has tracked 34,518,147 research outputs across all sources so far. Compared to these this one has done particularly well and is in the 95th percentile: it's in the top 5% of all research outputs ever tracked by Altmetric.
So far Altmetric has tracked 4,277 research outputs from this source. They typically receive a little more attention than average, with a mean Attention Score of 6.7. This one has done particularly well, scoring higher than 97% of its peers.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 178,195 tracked outputs that were published within six weeks on either side of this one in any source. This one has done particularly well, scoring higher than 99% of its contemporaries.
We're also able to compare this research output to 50 others from the same source and published within six weeks on either side of this one. This one has done particularly well, scoring higher than 92% of its contemporaries.
