Your Brain On Coffee (youtube, 2:45): The video runs for 3:14, but it’s a textbook advertisement starting at 2:45
They cover lethal dose of caffeine but nothing about:
- perceived decrease of activity difficulty
- laxative effect
Experiments show coffee naps are better than coffee or naps. A coffee nap is drinking a cup of coffee and then taking a quick (20 minute) nap.
In a few different studies, researchers at Loughborough University in the UK found that when tired participants took a 15-minute coffee nap, they went on to commit fewer errors in a driving simulator than when they were given only coffee, or only took a nap (or were given a decaf placebo). This was true even if they had trouble falling asleep, and just laid in bed half-asleep during the 15 minutes.
Meanwhile, a Japanese study found that people who took a caffeine nap before taking a series of memory tests performed significantly better on them compared to people who solely took a nap, or took a nap then washed their faces or had a bright light shone in their eyes. They also subjectively rated themselves as less tired.