Does cannabis adversely affect working memory function?

Fisk, J., Newcombe, R., Wareing, M. and Murphy, P. (2003) Does cannabis adversely affect working memory function? Cognitive Section Annual Conference, BPS.

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Claims that cannabis-related impairments in verbal fluency, associative learning, processing speed, and forward and backward digit span are indicative of a general deficit in working memory functioning remain to be tested. Thirty-five cannabis users categorised by pattern of use over the past three months: ‘always’, ‘frequently’, and ‘occasionally’ were compared to 21 nonusers on complex span measures including reading, computation, and visuo-spatial working memory as well as simple word, digit and spatial span measures. Profile analysis with user group between participants, test modality (verbal, arithmetic, and spatial) and complexity (simple versus complex) within participants, revealed a significant effect of user group. Bonferroni corrected pairwise comparisons showed that both heavy user groups were impaired relative to occasional users and nonusers. Significant interactions revealed that the cannabis related deficit was greater on the complex measures and on the arithmetic and visuo spatial tasks. It remains unclear whether these effects are short term or long lasting.

Item Type: Conference or Workshop Item (Paper)
Subjects: B Philosophy. Psychology. Religion > BF Psychology
R Medicine > RM Therapeutics. Pharmacology
Divisions: Psychology
Date Deposited: 25 Oct 2010 11:11

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