A new study published in the January edition of Personality and Individual Differences identifies two new categories of wakefulness: Some feel bright-eyed and bushy-tailed no matter what time it is, while others feel lethargic all day long.
The research conducted by Sleep scientists in Russia, of which they assembled 130 healthy people to a sleep lab and keeping them awake for 24 hours. While they were there, they were periodically asked to fill out surveys about how peppy or lazy they were currently feeling; the surveys also comprise questions about the previous week’s sleep habits and energy patterns.
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Twenty-nine of the participants reported more energy in the mornings, and 44 of them were most alert in the evenings. But two other types emerged: 25 individuals who said they felt alert in the mornings and evenings, and 32 more who never felt very awake – explained by scienceofus on nymag.
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The researchers are relying on the participants’ subjective opinion of their energy levels, instead of testing the subjects’ alertness throughout the day.
Also, if people are kept awake for 24 hours, they’d start to feel pretty lethargic as the hours go by.