Brain predictors of lapsing attention

Slow fluctuations in brain activity, known as slow waves, are a hallmark of sleep. However they also occur in awake people who have been sleep-deprived, where they are linked to poor task performance. In this study, researchers wondered if performance deficits in awake people might be caused by slow waves that trigger attention lapses.

They found that two types of attention lapse occurred when the EEG signal showed slow waves: mind-wandering and mind-blanking. Moreover, the brain region where the slow wave occurred determined whether the participant experienced mind-wandering or mind-blanking: when they occurred in frontal brain regions, mind-wandering tended to follow, but when they occurred in posterior regions, mind-blanking was more likely. Thus the authors show that lapses in attention are due to slow waves, and that the location of the slow wave accounts for the type of attention lapse.

Andrillon et al. (2021) Predicting lapses of attention with sleep-like slow waves. Nature Communications 12: 3657 DOI: https://doi.org/10.1038/s41467-021-23890-7

Student assessments of online source credibility

The internet is full of information, both trustworthy and untrustworthy. Students should be able to gauge the credibility of their sources and the strength of arguments presented in the material. But are they up to the task?

In this study of upper secondary school students in Finland, students were asked to evaluate a blog post and a YouTube video – both on the topic of child vaccination, respectively anti- and pro-vaccination – for their credibility and strength of argumentation. Students rightly questioned the credibility of the sources. However they did so on poor grounds, focusing on the “trustworthiness” or “authority” of the source, without noticing the one-sided argumentation. Students were also deemed poor at analysing the structure and logic of the source’s arguments. The authors recommend schools place more effort in improving how students analyse and interpret online information.

Marttunen et al. (2021) Student evaluations of the credibility and argumentation of online sources. The Journal of Educational Research 114(3): 294-305 DOI: https://doi.org/10.1080/00220671.2021.1929052

Easing remote traumatic memories in mice

Exposure therapy – in which a person who has suffered trauma is repeatedly exposed to reminders of the traumatic event, in a safe environment – is a common treatment for post-traumatic stress disorder (PTSD). However its effectiveness declines if applied long after the initial trauma. Knowing what brain mechanisms lead to this reduction in efficacy could help people who experience PTSD.

In this study of mice, researchers identify a neural pathway that specifically controls the extinction of remote fear memories. When activated, the pathway – from the nucleus reuniens of the thalamus to the basolateral amygdala – promotes extinction of remote (but not recent) fear memories. This is the first demonstration that long-lasting traumatic memories can be biologically reduced in severity.

Silva et al. (2021) A thalamo-amygdalar circuit underlying the extinction of remote fear memories. Nature Neuroscience 24: 964-974 https://pubmed.ncbi.nlm.nih.gov/34017129/

Gender differences in early literacy

It is generally accepted that girls outperform boys in literacy achievement upon entering school. But how long does this effect last after formal instruction, and what might underlie the discrepancy? In this longitudinal study of nearly 6000 Norwegian children, researchers first confirmed that on entering school, girls performed slightly but significantly better than boys in a range of literacy measures, including letter recognition, spelling, and word reading accuracy, but not vocabulary. However across the next two years, the gender discrepancy decreased as boys improved at a faster rate.

The authors believe the small initial difference in literacy might be due to girls’ preference for early literacy activities (for example in pre-school), rather than any innate ability. In their opinion, the gender difference is not worth addressing via intervention, and that early reading instruction should instead focus on overall high quality rather than addressing a specific initial gender imbalance.

McTigue et al. (2021) Gender differences in early literacy: Boys’ response to formal instruction. Journal of Educational Psychology 113(4): 690-705 DOI: https://dx.doi.org/10.1037/edu0000626