Our weekly round-up of the best psychology coverage from elsewhere on the web

A large review of studies published over the past 40 years has found little evidence that cannabis is helpful in treating mental health conditions like depression and anxiety, Ruby Prosser Scully reports in New Scientist. Researchers say that people should be wary of claims by companies producing medical cannabis, and that there is a need for more large-scale, well-controlled studies into the effects of the drug on different conditions.

“As more data points come in, understanding and interpretation become more complete — and more nuanced. Mischel’s original work on the marshmallow test wasn’t wrong. It was simply incomplete.” Erman Misirlisoy explores the “squishy” legacy of the marshmallow test at Elemental.

Another classic experiment has also been revisted this week: Benjamin Libet’s work on free will. In a 1983 experiment, Libet famously found that particular patterns of brain activity come before people’s conscious decision to make a movement — a finding that, it was originally claimed, showed free will to be an illusion. Since then, Libet’s findings have gone through various interpretations and re-interpretations — and Neuroskeptic has written about the latest iteration over at Discover Magazine.

Having narcissistic tendencies is related to lower levels of stress and depression, reports Emma Betuel at Inverse. Research suggests that narcissism is related to “mental toughness” and that this may provide a buffer against stressors — though there’s still work to be done to disentangle cause-and-effect.

Can science ever explain consciousness? Not by using our current scientific approaches, says Philip Goff at The Conversation, who argues in favour of a kind of “panpsychism” which conceptualises consciousness as a property of all matter.

Finally, the week wouldn’t be complete without some spooky Halloween links. Our own 2014 piece on the psychology of Halloween has proved very popular this week; elsewhere Frank T McAndrew explores the appeal of haunted houses while Rosemary Counter asks psychologists why so many kids claim to see ghosts.

And you can always count on psychologists and neuroscientists to bring their A-game to Halloween decorations, as demonstrated on Twitter this week:

My daughter and I made some halloween 🎃 treats as a tribute to Phineas Gage—the most important lesion patient in the history of #neuroscience. He survived an accident in which a large iron rod shot through his frontal lobe and impaired his emotional & social capacity. pic.twitter.com/GWGKfWCQtI — Jay Van Bavel (@jayvanbavel) October 28, 2019

Compiled by Matthew Warren (@MattbWarren), Editor of BPS Research Digest