„Taken together, our results suggest that cognition and white matter integrity are not only affected by experimental sleep deprivation but are also associated with natural differences in habitual sleep duration.

The findings of the present study are in line with other studies, which showed that cognitive performance and white matter are associated with sleep duration.„

On the other hand, I often hear stories of top-performing founders who claim to get by on just four hours of sleep or less over longer periods of time. Yet, getting too little sleep on an ongoing basis can have a negative impact on health. A study conducted by researchers at the University of Pennsylvania's Wharton School and Stanford University, found that employees who slept for six hours or less per night were more likely to be sick, take more time off work and have higher rates of absenteeism than those who got seven to eight hours of shut-eye each night. When I sleep less than 8 hours, I have this sensation of less energy throughout the day, regardless of how much coffee I'm taking in.

One way to reduce the amount of time you are spending in bed not working is to develop a system for falling asleep faster. This is a skill that can be learned. The first step is to develop a routine for going to bed. This should include the same steps every night, such as brushing your teeth, washing your face, and reading a book. The routine should take about 20 minutes or less.

Next, you need to develop a pre-sleep ritual that will help you relax and fall asleep faster. This could include taking a warm bath or shower before bedtime, listening to soothing music, to relaxing nature sounds, or reading something relaxing like poetry or fiction, but not nonfiction because that‘s harder to process by your brain. It’s important not to do anything too stimulating before bedtime because this will make it harder for you to fall asleep. For example, and I'm not suggesting that anyone here is doing that very often, avoid watching movies with lots of action and violence in them because they can stimulate your mind and body too much at night when you are trying to sleep.

There are many techniques to fall asleep faster, thereby reducing the time you lie awake in bed.

- Use the bed only for sleep, being sick or making love. Don’t read, watch TV, or eat in bed.

- Avoid naps during the day. If you must nap, keep it short (no more than 20 minutes) and don’t nap too close to bedtime.

- Exercise regularly but not within 3 hours of your regular bedtime. Exercise can make you feel tired but also revs up your metabolism, which may interfere with falling asleep quickly.

- Avoid blue light around bedtime. It‘s a potent stimulator of the brain’s retinal ganglion cells, relaying visual information to the brain, which is like queuing up mountains of data for the GPU. It also suppresses melatonin production at night, which makes us feel more awake.

- Be mindful about the sonic ambience in your bedroom. Is there distracting patterned noise like someone snoring, outside traffic or people talking? Mask it by playing unpredictable audio that covers up much of the audible spectrum, at the lowest volume possible just so it masks those noises enough.

(new here, I hope this was a helpful contribution)