Moral panics and poor sleep: the week’s best psychology links

A neural implant has allowed a paralysed individual to type by imagining writing letters. The implant of 200 electrodes in the premotor cortex picks up on the person's intentions to perform the movements associated with writing a given letter, translating these into a character on a screen. The individual was able to type 90 characters per minute with minimal errors, reports John Timmer at Ars Technica.

Robin Dunbar famously estimated that humans are limited to having around 150 friends, due to cognitive restrictions imposed by the size of our brains. Now a new study challenges the accuracy of Dunbar's number, as Jenny Gross reports at The New York Times (though Dunbar in turn disputes the findings).

Poor sleep can make us less able to focus on a task at hand and ignore distractions. That's according to a study comparing the performance on an attention test of 23 people with insomnia and 23 good sleepers. The results might not sound very surprising, but as researchers David James Robertson and Christopher B Miller point out at The Conversation, it hammers home how important sleep is for tasks like driving, where distractions can be deadly.

An analysis of bacteria in the teeth of Neanderthals and ancient Homo sapiens has found that both groups ate lots of starchy foods. This in turn suggests that their common ancestor was already eating these kinds of foods more than 600,000 years ago, reports Ann Gibbons at Science. This was a time when hominin brains became a lot bigger, so the researchers think that the starch gave ancient humans the energy needed to fuel this growth.

Moral panics about technology are common — but they rarely consider how those technologies evolve. After all, movies and video games from the 1970s are very different from their modern day counterparts. So have the supposed links between these technologies and mental health outcomes changed over time? Broadly, no, reports Tom Chivers at Unherd.

Researchers have explored how individual neurons across different parts of the brain behave when someone (well, a monkey) undergoes anaesthesia. At Wired, Max G Levy looks at the results of the studies, and ponders their implications for understanding consciousness.

Can we control our experience of disgust? At Scientific American, Charlie Kurth explores what the research says about combatting disgust in non-moral scenarios (think a medical student disgusted by the sight of blood) — and how this might extend to moral situations (when someone is disgusted by members of a certain social group, for instance).