Duffy et Al

• Individual Differences: However, it is important to note the differences between individuals when it comes to circadian cycles.
• Duffy et al. (2001) focused on chronotypes. They found that ‘morning people’ prefer to rise and go to bed early (about 6 am and 10 pm) whereas ‘evening people’ prefer to wake and go to bed later (about 10 am and 1 am).
• Chronotypes are natural preferences of the body for wakefulness and sleep
• This demonstrates that there may be innate individual differences in circadian rhythms, which suggests that researchers should focus on these differences during investigations.