Sleep, Wake and Phase Dependent Changes in Neurobehavioral Function under Forced Desynchrony

In the context of geriatric research, a growing body of evidence links normal age-related changes in sleep with many adverse health outcomes, especially a decline in cognition in older adults. The most important sleep alterations that continue to worsen after 60 years involve sleep timing, (especially early wake time, phase advance), sleep maintenance (continuity of sleep interrupted by numerous awakenings) and reduced amount of sigma activity (during non-rapid eye movement (NREM) sleep) associated with modifications of sleep spindle characteristics (density, amplitude, frequency) and spindle–Slow Wave coupling. After 60 years, there is a very clear gender-dependent deterioration in sleep. Even if there are degradations of sleep after 60 years, daytime wake level and especially daytime sleepiness is not modified with age. On the other hand, under sleep deprivation condition, older adults show smaller cognitive impairments than younger adults, suggesting an age-related lower vulnerability to extended wakefulness. These sleep and cognitive age-related modifications would be due to a reduced homeostatic drive and consequently a reduced sleep need, an attenuation of circadian drive (reduction of sleep forbidden zone in late afternoon and wake forbidden zone in early morning), a modification of the interaction of the circadian and homeostatic processes and/or an alteration of subcortical structures involved in generation of circadian and homeostatic drive, or connections to the cerebral cortex with age. The modifications and interactions of these two processes with age are still uncertain, and still require further investigation. The understanding of the respective contribution of circadian and homeostatic processes in the regulation of neurobehavioral function with aging present a challenge for improving health, management of cognitive decline and potential early chronobiological or sleep-wake interventions.

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Serum Micronutrient Status, Sleep Quality and Neurobehavioral function among Early Adolescents

Public Health Nutrition ◽

10.1017/s1368980021002329 ◽

2021 ◽

pp. 1-27

Author(s):

Xiaopeng Ji ◽

Charlene W. Compher ◽

Sharon Y. Irving ◽

Jinyoung Kim ◽

David F. Dinges ◽

...

Keyword(s):

Sleep Quality ◽

Early Adolescents ◽

Serum Zinc ◽

Spatial Processing ◽

Poor Sleep ◽

Poor Sleep Quality ◽

Attention Task ◽

Neurobehavioral Function ◽

Iron And Zinc ◽

Nonverbal Reasoning

Abstract Objective: To examine associations between serum micronutrients and neurobehavioral function and the mediating role of sleep quality in early adolescents. Design: In this cross-sectional study, peripheral blood samples were analyzed for iron and zinc levels. The Pittsburgh Sleep Quality Index and Penn Computerized Neurocognitive Battery were used to assess sleep quality and neurobehavioral function, respectively. The generalized linear regressions (bootstrap) were performed to estimate the associations. Setting: Jintan, China Participants: 226 adolescents (106 females) from the Jintan Child Cohort study. Results: Adolescents with low iron (< 75 ug/dl) (OR=1.29, p=0.04) and low zinc (< 70 ug/dl) (OR=1.58, p<0.001) were associated with increased odds for poor sleep quality. Adolescents with low iron and zinc were associated with fast (Iron: β=−1353.71, p=0.002, zinc: β=−2262.01, p=0.02) but less-accurate (Iron: β=−0.97, p=0.04; zinc: β=−1.76, p=0.04) performance on nonverbal reasoning task and poor sleep quality partially mediated the associations between low iron/zinc and nonverbal reasoning (p<0.05). Additionally, low iron was associated with a slower reaction on spatial processing task (β=276.94, p=0.04), and low zinc was associated with fast (β=−1781.83, p=0.03) but error-prone performance (β=−1.79, p=0.04) on spatial processing ability and slower reaction speed (β=12.82, p=0.03) on the attention task. We observed similar trends using a cutoff point of 75 ug/dl for low serum zinc, except for the association with attention task speed (p>0.05). Conclusion: Iron and zinc deficiencies may possibly be associated with poor sleep and neurobehavioral function among early adolescents. Poor sleep may partially mediate the relationship between micronutrients and neurobehavioral function.

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Remote Ischemic Postconditioning vs. Physical Exercise After Stroke: an Alternative Rehabilitation Strategy?

Molecular Neurobiology ◽

10.1007/s12035-021-02329-6 ◽

2021 ◽

Author(s):

Xiaokun Geng ◽

Qingzhu Wang ◽

Hangil Lee ◽

Christian Huber ◽

Melissa Wills ◽

...

Keyword(s):

Physical Exercise ◽

Treadmill Exercise ◽

Infarct Volume ◽

Ischemic Postconditioning ◽

Synaptic Proteins ◽

Neurological Deficits ◽

Sprague Dawley ◽

Neurobehavioral Function ◽

Remote Ischemic Postconditioning ◽

Function Tests

AbstractThere remain debates on neuroprotection and rehabilitation techniques for acute ischemic stroke patients. Therapeutic physical exercise following stroke has shown promise but is challenging to apply clinically. Ischemic conditioning, which has several clinical advantages, is a potential neuroprotective method for stroke rehabilitation that is less understood. In the present study, the rehabilitative properties and mechanisms of physical exercise and remote ischemic postconditioning (RIPostC) after stroke were compared and determined. A total of 248 adult male Sprague-Dawley rats were divided into five groups: (1) sham, (2) stroke, (3) stroke with intense treadmill exercise, (4) stroke with mild treadmill exercise, and (5) stroke with RIPostC. Focal ischemia was evaluated by infarct volume and neurological deficit. Long-term functional outcomes were represented through neurobehavioral function tests: adhesive removal, beam balance, forelimb placing, grid walk, rota-rod, and Morris water maze. To further understand the mechanisms underlying neurorehabilitation and verify the presence thereof, we measured mRNA and protein levels of neuroplasticity factors, synaptic proteins, angiogenesis factors, and regulation molecules, including HIF-1α, BDNF, TrkB, and CREB. The key role of HIF-1α was elucidated by using the inhibitor, YC-1. Both exercise intensities and RIPostC significantly decreased infarct volumes and neurological deficits and outperformed the stroke group in the neurobehavioral function tests. All treatment groups showed significant increases in mRNA and protein expression levels of the target molecules for neurogenesis, synaptogenesis, and angiogenesis, with intermittent further increases in the RIPostC group. HIF-1α inhibition nullified most beneficial effects and indicative molecule expressions, including HIF-1α, BDNF, TrkB, and CREB, in both procedures. RIPostC is equally, or superiorly, effective in inducing neuroprotection and rehabilitation compared to exercise in ischemic rats. HIF-1α likely plays an important role in the efficacy of neuroplasticity conditioning, possibly through HIF-1α/BDNF/TrkB/CREB regulation.

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Predictive Value of Subacute Heart Rate Variability for Determining Outcome Following Adolescent Concussion

Journal of Clinical Medicine ◽

10.3390/jcm10010161 ◽

2021 ◽

Vol 10 (1) ◽

pp. 161

Author(s):

Colt A. Coffman ◽

Jacob J. M. Kay ◽

Kat M. Saba ◽

Adam T. Harrison ◽

Jeffrey P. Holloway ◽

...

Keyword(s):

Heart Rate ◽

Heart Rate Variability ◽

Cognitive Performance ◽

Predictive Value ◽

System Integration ◽

Sports Medicine ◽

Clinical Symptoms ◽

Physiological Stress ◽

Neurological Dysfunction ◽

Neurobehavioral Function

Objective assessments of concussion recovery are crucial for facilitating effective clinical management. However, predictive tools for determining adolescent concussion outcomes are currently limited. Research suggests that heart rate variability (HRV) represents an indirect and objective marker of central and peripheral nervous system integration. Therefore, it may effectively identify underlying deficits and reliably predict the symptomology following concussion. Thus, the present study sought to evaluate the relationship between HRV and adolescent concussion outcomes. Furthermore, we sought to examine its predictive value for assessing outcomes. Fifty-five concussed adolescents (12–17 years old) recruited from a local sports medicine clinic were assessed during the initial subacute evaluation (within 15 days postinjury) and instructed to follow up for a post-acute evaluation. Self-reported clinical and depressive symptoms, neurobehavioral function, and cognitive performance were collected at each timepoint. Short-term HRV metrics via photoplethysmography were obtained under resting conditions and physiological stress. Regression analyses demonstrated significant associations between HRV metrics, clinical symptoms, neurobehavioral function, and cognitive performance at the subacute evaluation. Importantly, the analyses illustrated that subacute HRV metrics significantly predicted diminished post-acute neurobehavioral function and cognitive performance. These findings indicate that subacute HRV metrics may serve as a viable predictive biomarker for identifying underlying neurological dysfunction following concussion and predict late cognitive outcomes.

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One night sleep restriction impairs the cortical oxygenation responses

European Psychiatry ◽

10.1016/s0924-9338(11)73264-3 ◽

2011 ◽

Vol 26 (S2) ◽

pp. 1560-1560

Author(s):

S. Miyata ◽

A. Noda ◽

M. Ito ◽

K. Iwamoto ◽

N. Ozaki

Keyword(s):

Cognitive Function ◽

Performance Test ◽

Sleep Restriction ◽

Night Sleep ◽

Word Fluency ◽

Insufficient Sleep ◽

Neurobehavioral Function ◽

Significant Difference ◽

Concentration Changes ◽

Fluency Task

IntroductionSleep restriction has adverse effects on performance and neurobehavioral function. However, the mechanism of impaired performance and neurobehavioral function has not been studied yet.ObjectivesWe examined the effect of insufficient sleep on cerebral blood flow and cognitive function in 8 healthy adults (mean age 22.4 years).MethodsAll participants were in bed for 8 h (sufficient sleep), and for < 4 h (insufficient sleep). The oxyhemoglobin (oxyHb) level by a word fluency task was measured with a near-infrared spectroscopy recorder on the morning following sufficient and insufficient sleep periods. Wisconsin card sorting test (WCST), continuous performance test (CPT) and N-back test were evaluated on the same days.ResultsThe peak oxyHb level was significantly lower in the left and right frontal lobes after insufficient sleep than after sufficient sleep (left: 0.25 ± 0.10 vs. 0.70 ± 0.29 mmol, P < 0.05; right: 0.23 ± 0.13 vs. 0.73 ± 0.22 mmol, P < 0.05). There was no significant difference in the number of words generated during the word fluency task between sufficient and insufficient sleep states. The percentage of correct responses on CPT after insufficient sleep was significantly lower than that after sufficient sleep (86.6 ± 10.2 vs. 96.0 ± 4.9%, P < 0.05). The reaction time of WCST was significantly longer after insufficient sleep than after sufficient sleep (76.6 ± 13.4 vs. 70.6 ± 16.2 sec, P < 0.05).ConclusionsOne night sleep restriction decreased the concentration changes of oxyHb in brain tissue, leading to impaired cognitive function.

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