Maximum duration of a learning bout?
I teach a graduate seminar on Professional Musician Wellbeing for performing musician graduate students at McGill University in Montreal. Deliberate practice is one important topic. I can't find a study that proves the longest duration one can truly concentrate in one practice session (learning bout) although I have seen "45 minutes" and read related recommendations such as taking 10-second breaks every few minutes (from you almost one year ago), or recommendations for the maximum number of hours one can do deliberate practice / learning per day (4 hours). Is there a source for conclusive evidence, or is the reliable information more about the neuroscience of learning, brain chemistry, sleep, etc that promotes neuroplasticity? And each musician can follow those guidelines and figure out the durations of each practice session for themselves, and how many hours total they can practice per day?
Is it possible to get too much REM sleep?
I've been tracking my sleep for the past 2 years (WHOOP strap for 1 year, Oura ring for 1 year). My sleep score is optimal most days of the week, and I typically sleep 7-8 hours per night. However, the trend I've noticed lately is that I typically spend 3+ hours in REM, and not enough time in DEEP (less than 2 hours) sleep. What does this mean, and how can I shift my routine so that I feel less groggy upon waking?
Hiccups and how to stop them from happening
I develop chronic and sometimes severe hiccups every so often, more often lately. They can take the form of intense burping (always in prime numbers - 3, 5 7 or more), then hiccuping numerous time ina row, and sometimes an air lock in my esophagus. I’ve been to a gastroenterologist who has stuck too many tubes down my throat, always a clean picture, no polyps or scars, no acid reflux, nothing. I have been prescribed baclafin and Thorazine, and nether do anything to combat, prevent or decrease the frequency or intensity. What’s the next step?