New study: can cannabis alter speech production?

A new Australian study showed that speech production could be affected in individuals who consume cannabis.

An objective analysis of the audio samples for timing, vocal control and quality revealed subtle differences between cannabis users and non-users.

Stereotypical depictions of cannabis users speech often suggests low or laboured but there is little to no evidence supporting this. The aim of the study was to examine the long term effects of cannabis use on speech

The study

The researchers collected speech samples from 31 participants with a history of cannabis use and from 40 non-cannabis users. The participants completed speech tasks including monologues, sustained vowels, saying the days of the week and reading a phonetically balanced passage.

The objective analysis of the resulting audio samples for timing, vocal control and quality showed subtle differences between the two groups.

Read more: Treatment resistant stuttering: Could cannabis help patients?

Results

When researchers controlled for lifetime alcohol or tobacco use and applied a false discovery rate, only vocal and intensity differed. They highlighted that this changed in line with how long the users abstained from cannabis use.

The discovery, investigators write, is in “line with similar findings from gait and hand function studies.”

They wrote:“Our digital analysis of speech shows there may be a signal differentiating individuals with a history of recreational cannabis use from healthy controls.”

“We know that depressants or hallucinogenic drugs such as cannabis can cause acute changes in communication and speech rate, but the long-lasting effects of cannabis use on speech are not well-described.”

Read more: Study shows US remote workers used cannabis on the job

Previous studies

There are many different studies on the effects of cannabis for Tourettes syndrome. In a recent study, researchers from Yale University assessed the use of THX-110 (a combination of tetrahydracannabinoid (THC) and Palmitoylethanolamide (PEA) on patients with refractory Tourettes.

They noted that the tic symptoms improved within one week of the twelve week trial and continued to improve over time. The treatment with THX-10 was well-tolerated by most participants in the study.