Effects of Sleep Deprivation on Phase Synchronization as Assessed by Wavelet Phase Coherence Analysis of Prefrontal Tissue Oxyhemoglobin Signals

Abstract

PurposeTo reveal the physiological mechanism of the decline in cognitive function after sleep deprivation, a within-subject study was performed to assess sleep deprivation effects on phase synchronization, as revealed by wavelet phase coherence (WPCO) analysis of prefrontal tissue oxyhemoglobin signals.Materials and MethodsTwenty subjects (10 male and 10 female, 25.5 ± 3.5 years old) were recruited to participate in two tests: one without sleep deprivation (group A) and the other with 24 h of sleep deprivation (group B). Before the test, each subject underwent a subjective evaluation using visual analog scales. A cognitive task was performed by judging three random numbers. Continuous recordings of the near-infrared spectroscopy (NIRS) signals were obtained from both the left and right prefrontal lobes during rest, task, and post-task periods. The WPCO of cerebral Delta [HbO2] signals were analyzed for these three periods for both groups A and B.ResultsSix frequency intervals were defined: I: 0.6–2 Hz (cardiac activity), II: 0.145–0.6 Hz (respiratory activity), III: 0.052–0.145 Hz (myogenic activity), IV: 0.021–0.052 Hz (neurogenic activity), V: 0.0095–0.021 Hz (nitric oxide related endothelial activity) and VI: 0.005–0.0095 Hz (non-nitric oxide related endothelial activity). WPCO in intervals III (F = 5.955, p = 0.02) and V (F = 4.7, p = 0.037) was significantly lower in group B than in group A at rest. During the task period, WPCO in intervals III (F = 5.175, p = 0.029) and IV (F = 4.585, p = 0.039) was significantly lower in group B compared with group A. In the post-task recovery period, the WPCO in interval III (F = 6.125, p = 0.02) was significantly lower in group B compared with group A. Reaction time was significantly prolonged, and the accuracy rate and F1 score both declined after sleep deprivation.ConclusionsThe decline in WPCO after sleep deprivation indicates reduced phase synchronization between left and right prefrontal oxyhemoglobin oscillations, which may contribute to the diminished cognitive function.

Alteration in Brain Functional and Effective Connectivity in Subjects With Hypertension

“…For improving the accuracy of experimental results, NIRS signals denoizing was conducted by using the method described in our previous studies ( Li et al, 2013b ; Bu et al, 2017 ). A method based on moving standard deviation and spline interpolation was used to reduce movement artifacts in this study ( Scholkmann et al, 2010 ).…”

“…One method of characterizing the FC is based on the wavelet phase coherence (WPCO). Numerous previous studies have used this method as basis for evaluating FC between difference regions ( Dommer et al, 2012 ; Bu et al, 2016 , 2017 ). To fully understand the neurovascular coupling interaction among brain regions, we adopted EC, which can reveal the flow of information between the brain regions.…”

Functional connectivity analysis of distracted drivers based on the wavelet phase coherence of functional near-infrared spectroscopy signals

“…Some different, and possibly overlapping, physiological mechanisms such as the sympathetic nervous system, endothelial derived nitric oxide, and vascular myogenic responses could play some part in neurovascular coupling [ 55 ]. We previously demonstrated the oscillations in NIRS signals with six characteristic frequencies [ 49 , 56 , 57 ], possibly reflecting neurovascular coupling and systemic regulation activities. Overall, six frequency intervals were divided in WA and WPCO analyses based on their possible physiological origins: I, 0.6–2 Hz (cardiac activity); II, 0.145–0.6 Hz (respiration); III, 0.052–0.145 Hz (myogenic activity); IV, 0.021–0.052 Hz (neurogenic activity); and V, 0.0095–0.021 Hz (NO-related endothelial metabolic activity), VI, 0.005–0.0095Hz (NO-independent endothelial activity) [ 58 ].…”

Assessing low-frequency oscillations in cerebrovascular diseases and related conditions with near-infrared spectroscopy: a plausible method for evaluating cerebral autoregulation?

“…However, desynchronization has been shown with poor sleep quality in healthy elderly 102 and with sleep deprivation in healthy young people. 103 In contrast, the amplitude of OxyHb LFOs is sensitive to stimulations and increases with sympathetic stimulations, 24,100 deep breathing, 100 and poor sleep, 102 diminishes with hypercapnia, 80 while visual stimulations did not affect them. No difference has been observed across gender or between hemispheres, but the day-to-day amplitude ratio seems to fluctuate considerably.…”