Researchers of a case-control study tested their hypothesis that narcolepsy is linked to changes in brain pulsations, and looked to see if the pulsations can discern narcolepsy type 1 (NT1) from healthy controls. There were a total of 23 patients included in the study with NT1 who were imaged with ultrafast fMRI, as well as a total of 23 healthy controls who were matched with age and sex. Compared with healthy controls, greater variance and fractional variance in the very low frequency band was seen in NT1, with variances in cardiac and respiratory bands being lower. The differences in pulsations were noticeable in the ascending arousal network area. The researchers concluded that their findings reflect dynamics of impaired cerebrospinal fluid that could be connected to changed NT1 glymphatic circulation.
Reference: Järvelä M, Kananen J, Korhonen V, Huotari N, Ansakorpi H, Kiviniemi V. Increased very low frequency pulsations and decreased cardiorespiratory pulsations suggest altered brain clearance in narcolepsy. Commun Med (Lond). 2022;2:122. doi:10.1038/s43856-022-00187-4
