Participants in study who smoked drug daily for around three years had abnormally shaped hippocampus brain region which is vital to memoryThey also performed around 18 per cent worse in long-term memory tests than individuals who had never touched cannabisResults were uncovered using sophisticated brain-mapping scans taken two years after participants stopped smoking cannabis   By

Jenny Hope, Medical Correspondent for the Daily Mail

Published:
20:58 EST, 11 March 2015

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Updated:
05:30 EST, 12 March 2015

Teenagers who smoke cannabis for just three years could be damaging their long- term memory, researchers have warned.Participants in a study who had used the drug daily for around three years in their teens had an abnormally shaped hippocampus – a region of the brain vital to memory – by the time they were in their early 20s.They also performed around 18 per cent worse in long-term memory tests than individuals who had never touched the drug.The results were uncovered using sophisticated brain-mapping scans taken two years after they stopped smoking cannabis.Professor John Csernansky, from Northwestern University in the US, who co-led the research, said: ‘The memory processes that appear to be affected by cannabis are ones that we use every day to solve common problems and to sustain our relationships with friends and family.’ Those who took part in the Northwestern University study who smoked cannabis in their teens performed around 18 per cent worse in long-term memory tests than individuals who had never touched the drugThe study is one of the first to suggest that abnormally shaped brains in heavy cannabis users are directly related to memory impairment.The longer a participant had been exposed to cannabis the more misshapen their hippocampus appeared on scans.This could mean brain regions related to memory may be more susceptible to the effects of the drug the longer the abuse occurs.In total, 97 people took part in the study, including some who started smoking cannabis daily between the ages of 16 and 17 and continued for around three years. At the time of the study, they had been cannabis-free for around two years.The scientists used new computer software to fine-map MRI scans of the … – Click Here To Visit Article Source