A new study has found an association between regular cannabis use and an impaired ability to mentally travel back and forth in time. Those who use cannabis infrequently or who have never used the drug show no impairment in episodic foresight.

Episodic foresight is defined as the ability to project oneself into the future and mentally simulate situations and outcomes. Kimberly Mercuri, a researcher at the Australian Catholic University, and colleagues conducted a study involving 57 cannabis users and 57 control subjects.

In order to measure episodic foresight, the participants had to complete the Autobiographical Interview task, which involves responding to a cue word by either describing an event that occurred in the past or imagining a novel future event.

Regular cannabis users, defined here as those who smoked at least three times per week, showed difficulties imagining future scenarios, compared to the participants who had never used cannabis or use it less than once a week.

“The findings indicate that with regular cannabis use the ability to mentally time travel is negatively impacted; relative to people who have never used the drug and those who use it infrequently,” Mercuri told PsyPost.

“I guess the take home message is that there is growing evidence for possible cognitive deterioration with regular use which in turn can hinder the simplest of day-to-day tasks as the capacity to recall and imagine the self plays important roles other cognitive process (e.g decision making, goal setting).”

“Also, this deficit is not isolated to cannabis users, with another paper of ours indicating a significant impairment in future thinking observed in long-term opiate users,” the researcher said.

Mercuri notes that the findings do not imply that recreational cannabis use does not have consequences on episodic foresight. More research is required to understand the neurological underpinnings of the effect identified by the study. One important line of inquiry is whether the same effect is present in other drug-dependent groups.

The findings appeared in the Journal of Psychopharmacology.

Updated for grammar and spelling.

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