Effects of smoking marijuana on focal attention and brain blood flow

Daniel S O'Leary; Robert I Block; Julie A Koeppel; Susan K Schultz; Vincent A Magnotta; Laura Boles Ponto; G Leonard Watkins; Richard D Hichwa

doi:10.1002/hup.832

Back

Effects of smoking marijuana on focal attention and brain blood flow

Journal article

Peer reviewed

Effects of smoking marijuana on focal attention and brain blood flow

Daniel S O'Leary, Robert I Block, Julie A Koeppel, Susan K Schultz, Vincent A Magnotta, Laura Boles Ponto, G Leonard Watkins and Richard D Hichwa

Human psychopharmacology, Vol.22(3), pp.135-148

04/2007

DOI: 10.1002/hup.832

PMID: 17397099

View Online

Abstract

Using an attention task to control cognitive state, we previously found that smoking marijuana changes regional cerebral blood flow (rCBF). The present study measured rCBF during tasks requiring attention to left and right ears in different conditions. Twelve occasional marijuana users (mean age 23.5 years) were imaged with PET using [15O]water after smoking marijuana or placebo cigarettes as they performed a reaction time (RT) baseline task, and a dichotic listening task with attend-right- and attend-left-ear instructions. Smoking marijuana, but not placebo, resulted in increased normalized rCBF in orbital frontal cortex, anterior cingulate, temporal pole, insula, and cerebellum. RCBF was reduced in visual and auditory cortices. These changes occurred in all three tasks and replicated our earlier studies. They appear to reflect the direct effects of marijuana on the brain. Smoking marijuana lowered rCBF in auditory cortices compared to placebo but did not alter the normal pattern of attention-related rCBF asymmetry (i.e., greater rCBF in the temporal lobe contralateral to the direction of attention) that was also observed after placebo. These data indicate that marijuana has dramatic direct effects on rCBF, but causes relatively little change in the normal pattern of task-related rCBF on this auditory focused attention task.

Cerebrovascular Circulation - physiology

Humans

Magnetic Resonance Imaging - methods

Male

Reaction Time - physiology

Tomography, Emission-Computed - methods

Brain - metabolism

Neuropsychological Tests

Attention - physiology

Brain Mapping

Marijuana Smoking - pathology

Adult

Choice Behavior - physiology

Female

Marijuana Smoking - metabolism

Details

Title: Subtitle: Effects of smoking marijuana on focal attention and brain blood flow
Creators: Daniel S O'Leary - Department of Psychiatry, Roy J. and Lucille A. Carver College of Medicine, The University of Iowa, Iowa 52242, USA. daniel-oleary@uiowa.edu
Robert I Block
Julie A Koeppel
Susan K Schultz
Vincent A Magnotta
Laura Boles Ponto
G Leonard Watkins
Richard D Hichwa
Resource Type: Journal article
Publication Details: Human psychopharmacology, Vol.22(3), pp.135-148
DOI: 10.1002/hup.832
PMID: 17397099
NLM abbreviation: Hum Psychopharmacol
ISSN: 0885-6222
eISSN: 1099-1077
Publisher: England
Grant note: DA10551 / NIDA NIH HHS
Language: English
Date published: 04/2007
Academic Unit: Roy J. Carver Department of Biomedical Engineering; Radiology; Psychiatry; Research Administration; Iowa Neuroscience Institute; Pharmaceutical Sciences and Experimental Therapeutics; Physics and Astronomy; Radiation Oncology; Anesthesia; Internal Medicine
Record Identifier: 9984004075202771

Metrics

26 Record Views

43 Times Cited - Web of Science

See more details