As a scientist,Carl is concerned with the intensity of lights in the modern human environment.In his research project,Group A consists of volunteers who have agreed to sleep each night for a week with a 150 watt light bulb hanging over their bed.Group C will sleep in their usual environment.Alertness,blood pressure,respiration rate,and muscle tension will be sampled in the morning and evening.Carl is studying:

2 answers

What are your alternatives?

Effect of sleep variables on waking variables?
psychophysics