Inclusion Criteria:  Participants aged from 21 - 35 years and who have an average sleep duration of 6-6.5 h are eligible for this study.  Exclusion Criteria:  Participants who have an average sleep duration of less than 6 h or more than 6.5 h, who report sleep apnea symptoms, who report drinking more than 5 cups of caffeinated drinks a day, who have a BMI greater or equal to 30, or report elevated depression or anxiety symptoms will be excluded.