The previous descriptive comparative designs with paired control subjects have indicated that people with insomnia tend to have more stress, emotional arousal, and physiological activation as indicated by higher heart rates, metabolic rates, and SNS activity. This relationship is seen most strikingly in subjects displaying psychophysiological-type insomnia. The reciprocal issue is whether poor physical sleep triggers or reinforces excess stress activation. Another approach to probing the relationship of insomnia with sleep loss (i.e. psychophysiological-type) to stress arousal and activation is to mimic the sleep loss pattern in people without insomnia or to worsen the sleep in people with insomnia and assess the appropriate stress indicators.

In order to design such a study you elect to use the same sample selection process as suggested previously. Similarly, you will recruit and select a group of people with insomnia using criteria and scores from a 2-week sleep diary. You will match each person reporting no sleep problems to a person who meets criteria for insomnia on the basis of age, gender, and body mass index or select all subjects with a BMI within a narrow range of 23-25 kg/m². After an adaptation night, a second night PSG record is used to represent usual sleep. Subjects are qualified as having insomnia if they show sleep onset latency > 30 min. or sleep efficiency < 85% on both screening nights. Control subjects are retained and matched if they meet PSG criteria of sleep onset latency < 30 min and sleep efficiency90%.

For the next 7 nights, the control subjects will be exposed to a sleep pattern that mimics the pattern of their designated insomnia pair subject in terms of sleep onset, number of awakenings and sleep stage amounts as documented using PSG. During these nights, mood, body temperature and daytime sleepiness will be assessed. This design is referred to as a yoked control design, as used by Bonnet and Arand (Bonnet and Arand, 1996). When your research team looks at the results, you find that the sleep-disrupted group of previously good sleepers has lower self-reported tension/confusion (POMS) scores and daytime body temperatures, from pre- (baseline) to post-induced insomnia time points. They score higher in daytime sleepiness [lower multiple sleep latency test scores] as shown in the chart below (Bonnet and Arand, 1996).

Question 3.7.1

These outcomes (secondary to poor physical sleep imposed on good sleepers) are different from those seen in people with chronic insomnia.
	True
	False

Question 3.7.2

It is logical to suppose that these secondary outcomes are related to physical sleep loss, i.e. partial sleep deprivation.
	True
	False

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