04 September 2018Share
New research shows regular cannabis use impairs our capacity to envisage the future by hindering the brain’s ability to create a database of experience.
An Australian Catholic University study, published in the Journal of Psychopharmacology, found regular cannabis use severely impaired episodic foresight – our ability to mentally travel into our future.
Lead author Kimberly Mercuri, a psychologist specialising in drug and alcohol abuse, said the study provided new insight into how people with drug and alcohol addiction think.
“Our brain creates a database of experiences to help us prepare for and pre-experience future events,” Dr Mercuri said.
“It’s like scaffolding and gives us the ability to recognise the consequences of self-destructive behaviour.
“This research gives us an insight into the level of functioning of the people we see. It helps to inform the way we work with clients because we can now understand that reasons behind their behaviour may be due to more complex neurological functions.”
The study compared 57 cannabis users, aged 18 to 35 years, to 57 matched control subjects.
Episodic foresight was measured using an autobiographical interview task, which asked participants to respond to a cue word by either describing an experience or thinking up a future event.
Regular cannabis users — who reported smoking cannabis at least three times per week — had difficulty imagining future scenarios, compared to participants who didn’t use cannabis and those who used cannabis less than once a week.
“There is growing evidence for cognitive deterioration with regular use which can hinder the simplest of day-to-day tasks,” Dr Mercuri said.
“The capacity to recall and imagine the self also plays important roles in other cognitive process such as decision making and goal setting.”
Dr Mercuri said much of current addiction treatment is focused on planning the future – for example how a person will say no to drugs when they encounter them out in the community.
Knowing about marijuana's effect on our ability to make future personal plans can help drive alternative treatment.
“We can make the goal setting quite close to the here and now by asking what we can do right now to make it better rather than focusing on a later goal,” she said.
“This type of information can help clinicians to deliver better outcomes.”