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# Observing patients in a sleep clinic

## Problem

Sleep is an essential bodily process that can have disastrous effects on a person’s ability to function if it is disrupted. Individuals who have sleep dysfunction often need to seek out specialized treatment from sleep clinics, which are designed in such a way that studies can be performed on the sleep cycles of patients who are experiencing any variety of symptoms. The patients commit to sleeping in the lab for at least one entire night; while they are in the lab they are connected to machines that monitor their breathing and heart rate. In addition, doctors place electrodes on certain parts of each patient’s scalp so that an electroencephalogram (EEG) can monitor the patient’s brainwaves. The electrodes must remain in place all night to capture the full range of brain activity, from waking stages to deep sleep. For different patients, however, doctors may focus on a particular pattern of activity or a particular stage of sleep. One sleep center’s patient data is outlined in Table 1.
Table 1
PatientSymptoms or observations
Patient KHas reported she is unable to sleep through any type of noise. Causing significant distress in her life and marriage; wakes up at slightest sound.
Patient BObserved beta waves for hours; present during most of the night.
Patient QHas reported that she is always fatigued when she wakes up, although she can’t recall having trouble sleeping. Doctors monitoring Patient Q notice that she stops breathing several times during the night. Each time, she wakes up briefly, starts breathing again, and falls back asleep.
What type of brainwave is most likely to be absent from Patient Q’s EEG?