Lotta Edholm called for the return to traditional learning, with handwriting favored over keyboarding skills and the printed page prized above illuminated screens, after complaints snowballed of graduates who could barely function without devices in front of them. Since schools returned this month, teachers have downplayed the previous emphasis on independent learning and the use of online resources.

Even so, there’s some evidence that light therapy may have a similar effect on the brain to many antidepressants. In a study published in 2016, 11 patients with SAD treated with two weeks of light therapy saw plunging levels of serotonin transporter binding – a measure of how quickly serotonin’s activity is curtailed. Their levels became similar to those seen during summertime. There is other evidence, besides. At the back of our eyes, an unusual type of photoreceptor has been found that seems to help synchronize our circadian rhythms to the 24-hour cycle of light and dark.