New research shows that cannabis users experience increased cortical activation during the brain’s resting state.
The resulting “noisy brain” could impair brain activity and disrupt cognitive processes, according Dr. Shikha Prashad, the study’s lead author and a research scientist at the Center for BrainHealth at The University of Texas at Dallas.
“This study is the first to characterize global cortical activation and both inter- and intrahemispheric functional connectivity during resting state in cannabis users,” said Prashad, who works in the lab of Dr. Francesca M. Filbey.
For the study, the researchers collected electroencephalogram (EEG) data from 38 participants: 17 cannabis users and 21 nonusers. The EEG test measures electrical activity in the brain, also known as brain waves.
They measured the synchronization of brain waves to evaluate the strength of the brain signals in different cortical regions. This measures communication between different regions of the brain, according to the researchers.
The findings demonstrated that cannabis users exhibited increased synchronization — or activation — of most of the different types of brain waves, compared to nonusers. Similar results have been found in other studies of heroin, alcohol and cocaine users.
The scientists also observed greater cortical communication among the frontal regions of the brain in cannabis users.
According to Prashad, this could signify that cannabis users have difficulty inhibiting neural activity which has been observed in Filbey’s previous studies. This would cause them to exert more effort as they attempted to stop doing certain tasks, she explained.
Changes in communication between the brain’s cortical areas could also be related to cognitive impairments correlated with cannabis use, she added.
These results could contribute to understanding cognitive impairments and the development of electrophysiological patterns to help map and evaluate the success of interventions, Prashad noted.
She added that further studies are needed during task-related activity for comparison, Prashad said.
The study was published in the journal NeuroImage.