Selected problems of analysis and interpretation of the effects of sleep deprivation on temperature and performance...

One of the major methodological-analytic problems encountered by researchers in sleep deprivation involves the examination and analysis of the relationship between sleep loss and rhythmic influences on performance. The comparison of performance rhythms with physiological rhythms, e.g., body temperature, generated under the same conditions of sleep deprivation, has become an important means of testing for an endogenous source of the rhythmicity in the data and for clarifying the nature of the proposed oscillator system. Should the data sets be correlated before or after their separation into monotonic and rhythmic parts? Correlating the raw data without separating them into their components can yield negative results, while, in reality, some of the major underlying rhythms may be highly related. The example used in this chapter showed strong cross correlations of the circadian components of temperature and two performance tasks. Sleep deprivation is thus seen to interact with performance rhythms. This interaction is only revealed after the data are analyzed and broken into their component parts. This procedure leads to the conclusion that certain performance rhythms and temperature may share the same generating oscillators.