A team at Washington State University studied cannabis-seeking behaviour in rats and published the results in Neuropsychopharmacology. They created a behavioural profile for each animal, testing social behaviour, sex, cognition, reward and arousal. For three weeks, rats were observed one hour daily, and each could nose-poke to release three seconds of cannabis vapor in an airtight chamber. Students recorded the number of nose-pokes.
The researchers measured baseline corticosterone, the rodent equivalent of human cortisol, and found a direct correlation: rats with higher natural corticosterone self-administered more cannabis. Short-term stress after a challenge did not show a link. The team also found that rats with lower cognitive flexibility and those relying on visual cues showed stronger cannabis-seeking behaviour.
Difficult words
- behaviour — Actions and reactions of animals or people.
- cognition — Mental processes like thinking and remembering.
- corticosterone — A hormone in rodents similar to cortisol.
- correlation — A relationship between two measured things.
- self-administer — Give a drug to oneself without help.self-administered
- cognitive flexibility — Ability to change thinking or behaviour.
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Which of the tested behaviours (social behaviour, sex, cognition, reward, arousal) do you think best predicts drug seeking? Why?
- How could the finding about visual cues help design ways to reduce drug-seeking behaviour?
- Do you think short-term stress affects drug use in people the same way it did in the rats? Explain briefly.
Related articles
People with AMD Judge Car Arrival Times Like Others
A virtual reality study compared adults with age-related macular degeneration (AMD) and adults with normal vision. Both groups judged vehicle arrival times similarly; vision and sound were used together, and a multimodal benefit did not appear.
Financial worries disrupt sleep in National Guard members
A study of full-time Army and Air National Guard members found that financial stress leads to tense bedtime habits and poorer sleep. Researchers measured stress, bedtime behaviours, and sleep using surveys and wrist actigraphs.