Some studies have concluded there are links between chronic marijuana use and changes in the human brain.
But new research from Washington University in St. Louis, the University of Missouri, and Kings College in London concludes that cannabis has no unusual effect on brain volume in the hippocampus, amygdala, ventral striatum, and orbitofrontal cortex.
Researchers studied those who used and didn’t use pot among 483 siblings to measure changes in the brain.
Changes among the weed smokers were determined to be “within the range of normal variation,” according to the study, published JAMA Psychiatry. Shared genetics were more likely to blame for changes in the noggin’, they said.
The study says researchers “found no evidence for the causal influence of cannabis exposure” on brain changes.
Previous research claimed that using cannabis could effect memory, emotion and decision-making. The latest research concludes, according to an abstract:
Differences in amygdala volume in cannabis users were attributable to common predispositional factors, genetic or environmental in origin, with little support for causal influences.