That study was conducted at Harvard a number of years ago. Based on their sort of comprehensive neuropsych IQ tests, they didn't see any differences between the heavy users, the recently abstinent, and those who were never users.
Associate Professor, University of British Columbia, As an Individual
That study was conducted at Harvard a number of years ago. Based on their sort of comprehensive neuropsych IQ tests, they didn't see any differences between the heavy users, the recently abstinent, and those who were never users.
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