AO3

• One strength of research into circadian rhythms is that it has shown that light influences circadian rhythms. For example, Hughes found that extremes of daylight found in polar regions of the world may be responsible for variations in circadian hormone release.
• A second strength is that it has shown that temperature is also an important factor in circadian rhythms. For example, Buhr et al. found that fluctuations in temperature on a 24-hour circadian or inactive rhythm set the
• However, one limitation of research into circadian rhythms is that some of it is flawed. For example, early studies assumed that dim, artificial light would not affect circadian rhythms, but more recent research has shown this is incorrect, weakening the evidence of earlier studies.