I am sure ;-) it’s not primarily blue light, but the mental activity. Years of bad habits, er ‘personal research,’ have taught me that TV and smartphone usage can be used to help me sleep, or inhibit it. If I watch something on TV that is lighthearted, especially if I’ve seen it before, it’s like a someone is telling me a bedtime story: it calms me and helps me sleep. If I watch something new, stressful, etc., then my mind stays awake to anticipate what will happen. (Interestingly, watching “Sherlock” episodes puts me right sleep — not because they are boring — quite thee opposite — but because I’ve seen them multiple times and the known outcomes, plus British accents and even tones and mumbling, calm me.) For smartphones, reading work email is terrible (didn’t take long to figure that out), but answering texts from friends, updating my tasks (with dates I convince myself I can get them all done by), knowing my calendar for tomorrow, etc., all give me peace of mind so I can let the day’s activities and stresses fade away.
