Correct!
3. Increased brain metabolism during both asleep and awake compared to controls.

Insomnia is a condition of physiological hyperarousal during both sleep and wakefulness (1, 2).  There is increased activation of somatic, cortical and cognitive functioning during the day as well as night.

• Insomniacs have elevated heart rate compared to good sleepers across the sleep-wake cycle
• Body temperature and blood pressure are higher in insomniacs.
• There is a nocturnal and diurnal increase in the whole-body metabolic rate.
• Levels of cortisol and adrenocorticotropic hormone during sleep are elevated. 
• Insomniacs show increased high-frequency electroencephalographic (EEG) beta and sleep spindle (sigma) activity during non–rapid eye movement sleep.
• Alpha and beta EEG frequencies are increased both in wake and sleep.
• One study utilized [(18)F]Fluorodeoxyglucose positron emission tomography to assess regional cerebral glucose metabolism in 7 patients with insomnia and 20 healthy subjects (3). Compared with healthy subjects, patients with insomnia showed greater global cerebral glucose metabolism during sleep and while awake. There was also a smaller decline in relative metabolism from waking to sleep states in wake-promoting regions compared to controls.

References

1. Buysse DJ. Insomnia. JAMA. 2013;309:706-16. [CrossRef] [PubMed] 
2. Bonnet MH, Arand DL. Hyperarousal and insomnia: state of the science. Sleep Med Rev. 2010;14:9-15. [CrossRef] [PubMed] 
3. Nofzinger EA, Buysse DJ, Germain A, Price JC, Miewald JM, Kupfer DJ. Functional neuroimaging evidence for hyperarousal in insomnia. Am J Psychiatry. 2004;161:2126-8. [CrossRef] [PubMed]

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