February is the tail end of winter and often has the worst weather of the year. Those of us in four-season zones are tired of being cold and can’t wait for spring. Maybe that’s the reason that February is so short and full of holidays! You’d also think that February might be the peak month for Seasonal Affective Disorder, or SAD. But a study of over 34,000 adults show that about the same number of people show symptoms of depression no matter what time of year it is. Another study used fewer people but measured more parameters, including doing tasks while hooked up to a brain scanner.
The participants’ feelings of alertness, their emotional state, and melatonin levels mostly didn’t vary with the seasons, and they actually performed equally well on both tasks in the scanner regardless of the time of year, thus undermining the idea that the winter has an adverse effect on our mental abilities (more on this shortly). One question on mood did show some seasonal variation, but participants’ moods were lowest in the fall, not winter. In terms of underlying brain function, participants’ neural activity was highest during the memory task for those participants tested in spring and lowest for those tested in the fall, so, far from being a special case, winter brain activity sat in the middle.
Meanwhile, during the vigilance task, brain activity was lowest in the winter and highest in the summer. Some media outlets have interpreted this as evidence for winter sluggishness, but as the participants’ performance and alertness was as good in winter as at other times of year, their reduced winter brain activity can actually be seen as a sign of improved efficiency. For comparison, consider research showing how the more expert people become at a task, the less brain activity is seen while they perform that task, as the brain becomes more efficient.
There are other studies that focused on how weather affects our mood and abilities, including one from the Arctic Circle. The upshot is that winter weather may be tough, but humans have learned to deal with it pretty well, for the most part. Read more about this research at The Science of Us. -via Digg