What happens to our cognition in the darkest depths of winter?

Tim Brennen in Psyche:

We tested 100 participants twice on a range of tests: some took them first in summer and then winter, and some in the opposite order. Among the tasks, there was a test of pure speed (‘press this button as quickly as possible as soon as you see a circle in the middle of the screen’); a test of immediate memory for digits; a test of memory for words presented 10 minutes previously; the classic ‘Stroop test’ (that measures mental control); an alertness task; a face-recognition task; a time-estimation task; and a verbal fluency task. Most tests showed no difference in performance between summer and winter, and, of those that did, four out of five actually suggested a winter advantage. The ‘Arctic cognition’ paper, as we called it in 2000, was disseminated over the whole world and had its 15 minutes of fame in newspapers and magazines.

I moved on to other research topics, but last year, now working at the University of Oslo at a mere 59°N, I decided to revisit the science of human seasonality.

More here.