Electric fish and children’s play: the week’s best psychology links

Electric fish seem to have mastered the art of the pause, writes Katherine J. Wu at The Atlantic. Brienomyrus brachyistius communicate by producing a series of electrical pulses. But researchers have found that the fish sometimes pause during their "conversations", apparently as a signal that what they are about to communicate is important — similar to a "dramatic pause" in human speech.

As we covered in a recent podcast, play is a vital part of children's development. But how do the toys we choose to give kids shape their interests and skills? At BBC Future, Melissa Hogenboom explores how gendered toys can reinforce existing stereotypes and biases.

Researchers have allowed a bind man to see again after 40 years, through the use of light-sensitive proteins injected into cells in the eye. With the help of specialised goggles, the man was able to make out high-contrast images, reports Sara Reardon at Nature. The study represents the first clinical use of optogenetics, a technique often used in basic neuroscience research. 

..and in other optogenetics news, researchers have used the technique to manipulate social behaviours in mice. After inducing synchronous patterns of activity in the medial prefrontal cortex of two mice, the team found that the animals became more social, reports Virginia Hughes at The New York Times. The work has interesting parallels with that on "interbrain synchrony" in humans.

Depending on the kinds of questions researchers ask, human memory can be seen as quite extraordinary — or really bad. Nicole C. Rust examines the two perspectives at Scientific American.

Psychologists surely know enough about the replication crisis now to avoid uncritically citing work known to have issues… right? Not according to a recent study, which looked at how often researchers cite work that has failed to replicate, compared to more robust findings. The team found that studies with replication issues were cited 153 times more often than those without, reports John Timmer at Ars Technica — and those citations rarely mentioned the fact that the original paper had not replicated.