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Journal of Experimental Zoology. Part... Jul 2024Sleep is a prominent physiological state observed across the animal kingdom. Yet, for some animals, our ability to identify sleep can be masked by behaviors otherwise...
Sleep is a prominent physiological state observed across the animal kingdom. Yet, for some animals, our ability to identify sleep can be masked by behaviors otherwise associated with being awake, such as for some sharks that must swim continuously to push oxygenated seawater over their gills to breathe. We know that sleep in buccal pumping sharks with clear rest/activity cycles, such as draughtsboard sharks (Cephaloscyllium isabellum, Bonnaterre, 1788), manifests as a behavioral shutdown, postural relaxation, reduced responsiveness, and a lowered metabolic rate. However, these features of sleep do not lend themselves well to animals that swim nonstop. In addition to video and accelerometry recordings, we tried to explore the electrophysiological correlates of sleep in draughtsboard sharks using electroencephalography (EEG), electromyography, and electrooculography, while monitoring brain temperature. The seven channels of EEG activity had a surprising level of (apparent) instability when animals were swimming, but also when sleeping. The amount of stable EEG signals was too low for replication within- and across individuals. Eye movements were not measurable, owing to instability of the reference electrode. Based on an established behavioral characterization of sleep in draughtsboard sharks, we offer the original finding that muscle tone was strongest during active wakefulness, lower in quietly awake sharks, and lowest in sleeping sharks. We also offer several critical suggestions on how to improve techniques for characterizing sleep electrophysiology in future studies on elasmobranchs, particularly for those that swim continuously. Ultimately, these approaches will provide important insights into the evolutionary confluence of behaviors typically associated with wakefulness and sleep.
PubMed: 38957102
DOI: 10.1002/jez.2846 -
European Journal of Sport Science Jul 2024An important application for training instructions is found in directing one's attentional focus. This direction can occur in different internal, external, or holistic...
An important application for training instructions is found in directing one's attentional focus. This direction can occur in different internal, external, or holistic forms. However, comparison between these three forms of instructions is a relatively recent development rarely reported at different skill levels or various sports including karate. Therefore, the present study attempts to investigate the effects of three forms of instructions on standing long jump performance in skilled and novice karatekas. The participants were 60 skilled and novice karatekas (all females; mean age: 21.32 ± 1.65) who completed 12 standing long jump trials under different focus conditions (3 trials for each condition: internal, external, holistic and control condition) in a counterbalanced order. Our findings suggested significant main effects, indicating that skilled karatekas outperformed the novices. The findings also showed that regardless of skill levels, the participants exhibited similar performance under external and holistic focus conditions while performance in both of these conditions was superior compared to performance under internal focus and control conditions. No difference was observed between the control and internal focus conditions. It seems that skilled and novice karatekas may benefit from holistic and external focus of attention instructions which enhance their motor performance. Thus, it is recommended that coaches should incorporate these two types of attentional focus instructions into their training sessions.
Topics: Humans; Female; Attention; Martial Arts; Athletic Performance; Young Adult; Motor Skills
PubMed: 38956799
DOI: 10.1002/ejsc.12152 -
Scientific Reports Jul 2024Our study aimed to investigate the relationship between sleep-wake changes and depressive symptoms events among midlife women. We enrolled 1579 women aged 44-56 years...
Our study aimed to investigate the relationship between sleep-wake changes and depressive symptoms events among midlife women. We enrolled 1579 women aged 44-56 years who had no clinically relevant depressive symptoms at baseline. Depressive symptoms were assessed at each visit using the Center for Epidemiologic Studies Depression scale. At the third and fourth follow-up visits, women reported their sleep habits. The sleep midpoint was defined as the time to fall asleep plus one-half of the sleep duration. Sleep-wake changes were determined by the difference in the midpoint of sleep between the third and fourth visits, which were 1 year apart. The median follow-up time was 7 years (range 1-7 years). Cox proportional hazard models were fitted to calculate hazard ratios and 95% confidence intervals for the incidence of depressive symptoms associated with sleep-wake changes. After adjusting for potential confounding factors, the hazard ratio (95% confidence interval) of depressive symptoms for severe sleep midpoint changes was 1.51 (1.12, 2.05) compared with mild sleep midpoint changes. This relationship remained statistically significant and changed little when additionally controlling for sleep duration, sleep quality, insomnia symptoms, use of sleep medications, use of nervous medications, glucose, insulin, lipids, dietary energy intake, and C-reactive protein. Our findings indicate that exposure to long-term severe sleep-wake changes increases the risk of depressive symptoms in midlife women.
Topics: Humans; Female; Middle Aged; Depression; Adult; Sleep; Incidence; Proportional Hazards Models; Sleep Quality; Wakefulness; Risk Factors; Sleep Initiation and Maintenance Disorders
PubMed: 38956441
DOI: 10.1038/s41598-024-66145-3 -
Scientific Reports Jul 2024Recent studies have shown a growing interest in the so-called "aperiodic" component of the EEG power spectrum, which describes the overall trend of the whole spectrum...
Recent studies have shown a growing interest in the so-called "aperiodic" component of the EEG power spectrum, which describes the overall trend of the whole spectrum with a linear or exponential function. In the field of brain aging, this aperiodic component is associated both with age-related changes and performance on cognitive tasks. This study aims to elucidate the potential role of education in moderating the relationship between resting-state EEG features (including aperiodic component) and cognitive performance in aging. N = 179 healthy participants of the "Leipzig Study for Mind-Body-Emotion Interactions" (LEMON) dataset were divided into three groups based on age and education. Older adults exhibited lower exponent, offset (i.e. measures of aperiodic component), and Individual Alpha Peak Frequency (IAPF) as compared to younger adults. Moreover, visual attention and working memory were differently associated with the aperiodic component depending on education: in older adults with high education, higher exponent predicted slower processing speed and less working memory capacity, while an opposite trend was found in those with low education. While further investigation is needed, this study shows the potential modulatory role of education in the relationship between the aperiodic component of the EEG power spectrum and aging cognition.
Topics: Humans; Electroencephalography; Cognition; Male; Female; Aged; Aging; Adult; Middle Aged; Memory, Short-Term; Young Adult; Brain; Educational Status; Attention; Aged, 80 and over
PubMed: 38956186
DOI: 10.1038/s41598-024-66049-2 -
Nature Communications Jul 2024Attention supports decision making by selecting the features that are relevant for decisions. Selective enhancement of the relevant features and inhibition of...
Attention supports decision making by selecting the features that are relevant for decisions. Selective enhancement of the relevant features and inhibition of distractors has been proposed as potential neural mechanisms driving this selection process. Yet, how attention operates when relevance cannot be directly determined, and the attention signal needs to be internally constructed is less understood. Here we recorded from populations of neurons in the anterior cingulate cortex (ACC) of mice in an attention-shifting task where relevance of stimulus modalities changed across blocks of trials. In contrast with V1 recordings, decoding of the irrelevant modality gradually declined in ACC after an initial transient. Our analytical proof and a recurrent neural network model of the task revealed mutually inhibiting connections that produced context-gated suppression as observed in mice. Using this RNN model we predicted a correlation between contextual modulation of individual neurons and their stimulus drive, which we confirmed in ACC but not in V1.
Topics: Animals; Gyrus Cinguli; Decision Making; Attention; Mice; Neurons; Male; Mice, Inbred C57BL; Models, Neurological; Photic Stimulation; Visual Cortex
PubMed: 38956080
DOI: 10.1038/s41467-024-49845-2 -
BMJ Case Reports Jul 2024Camptodactyly-arthropathy-coxa vara-pericarditis syndrome (CACP) is a rare autosomal recessive disease caused by mutation in proteoglycan 4 (PRG4) gene on chromosome...
Camptodactyly-arthropathy-coxa vara-pericarditis syndrome (CACP) is a rare autosomal recessive disease caused by mutation in proteoglycan 4 (PRG4) gene on chromosome 1q25-q31. We faced a dilemma and delay in diagnosis in two sisters. The elder sister had pericardial effusion with constrictive pericarditis, underwent pericardiectomy and received empirical treatment for suspected tuberculosis. After 2 years, she developed bilateral knee swelling with restriction of movement. At the same time, her younger sister also presented with bilateral knee swelling which aroused the suspicion of genetic disease. The whole-genome sequencing revealed homozygous PRG4 mutation suggestive of CACP syndrome.
Topics: Humans; Female; Coxa Vara; Proteoglycans; Hand Deformities, Congenital; Arthropathy, Neurogenic; Pericardial Effusion; Upper Extremity Deformities, Congenital; Pericarditis, Constrictive; Lower Extremity Deformities, Congenital; Pericardiectomy; Mutation; Diagnosis, Differential; Synovitis
PubMed: 38955384
DOI: 10.1136/bcr-2024-260146 -
Complementary Medicine Research Jul 2024Introduction Previously an intervention involving volitional slow breathing reduced trait food craving with protective effects on cardiac vagal activity (CVA). Breathing...
Introduction Previously an intervention involving volitional slow breathing reduced trait food craving with protective effects on cardiac vagal activity (CVA). Breathing with a low inspiration-to-expiration ratio (i/e) also increases CVA. High CVA was separately associated with low unregulated eating and lesser impulsivity. Hence the present study assessed breathing with a low i/e for effects on state food craving, hunger and satiety, state impulsivity, and heart rate variability (HRV) in healthy obese persons. Methods Forty obese persons were randomized to two groups. The intervention group (mean age ± SD, 41.15 ± 12.63, M: F, 10:10) practiced metronome-regulated breathing with low i/e at 12 breaths per minute (expiration 72% of total breath duration) (bpm) and attained expiration 55.8% of total breath duration, while the active control group (mean age ± SD, 44.45 ± 11.06, M: F, 13:07) sat motionless and directed their gaze and awareness to the stationary metronome without modifying their breath consciously. The HRV was recorded before, during and after breathing intervention (or control) (standard limb lead I, acquisition at 2000 Hz, with a LF filter = 0.5 Hz and HF filter = 50 Hz. Time-domain and frequency-domain HRV parameters were obtained with Kubios software. State food craving, hunger and satiety were recorded before and after the intervention/control. Results The intervention group decreased total state food craving scores and the sub-domains (i.e., desire to eat, positive reinforcement, lack of control and hunger), increased current satisfaction with food, decreased total state impulsivity (repeated measures ANOVA, p < 0.05 in all cases), increased HF-HRV and RMSSD (linear mixed model analyses with age and gender as fixed factors; p<0.05 in all cases) during the intervention compared to the preceding baseline. The intervention group also showed an increase in positive mood and a decrease in aroused and negative mood states. Conclusion Changes in state food craving and impulsivity could be related to an increase in HRV or to changes in subjective relaxation and positive mood or to both.
PubMed: 38955170
DOI: 10.1159/000539618 -
Journal of Psychosomatic Research Jun 2024Heart rate variability (HRV) reflects the capacity to adapt to internal and environmental changes. Decreased HRV may indicate inadequate adaptive capacity. This study...
OBJECTIVES
Heart rate variability (HRV) reflects the capacity to adapt to internal and environmental changes. Decreased HRV may indicate inadequate adaptive capacity. This study aims to investigate the relationship between the heart and brain's adaptive abilities, both at rest and when negative emotions are stimulated in depression.
SUBJECTS AND METHODS
The study included 30 patients (20 female, 10 male) with major depression (mean age = 29.8 ± 7.8) and 30 healthy controls, all of whom had similar characteristics in terms of age and gender, selected through convenience sampling. The patients were drug-free at the time of the assessment. Holter recordings were obtained while subjects watched videos stimulating anger, fear, sadness, and a neutral video, and at rest, HRV parameters were calculated. To control for interindividual variability and account for paired sampling, linear mixed effects models were employed.
RESULTS
Watching the 'sadness video' led to an increase in low frequency band (LF) [LF change (Control vs depression); Difference:-620.80 df:107 t:-2.093 P:0.039] and LF/high frequency band ratio (LF/HF) [LF/HF change (control vs depression group); Difference:-1.718 df:105 t:-2.374 P:0.020] in the depression group. The video led to a decrease in LF and LF/HF in the controls. Although the differences between the conditions and interactions with the group were significant, the effects were independent of depression severity.
CONCLUSION
In depression, brain's regulatory effect on the heart differed from controls in the sadness condition, possibly due to increased arousal levels in subjects with depression and their inability to suppress sympathetic activity when a state of sadness is stimulated.
PubMed: 38954865
DOI: 10.1016/j.jpsychores.2024.111855 -
Sleep Jul 2024The Maintenance of Wakefulness Test (MWT) is a widely accepted objective test used to evaluate daytime somnolence and is commonly used in clinical studies evaluating...
The Maintenance of Wakefulness Test (MWT) is a widely accepted objective test used to evaluate daytime somnolence and is commonly used in clinical studies evaluating novel therapeutics for excessive daytime sleepiness. In the latter, sleep onset latency (SOL) is typically the sole MWT endpoint. Here, we explored microsleeps, sleep probability measures derived from automated sleep scoring, and quantitative electroencephalography (qEEG) features as additional MWT biomarkers of daytime sleepiness, using data from a phase 1B trial of the selective orexin receptor 2 agonist danavorexton (TAK-925) in people with narcolepsy type 1 (NT1) or type 2 (NT2). Danavorexton treatment reduced the rate and duration of microsleeps during the MWT in NT1 (days 1 and 7; p ≤ 0.005) and microsleep rate in NT2 (days 1 and 7; p < 0.0001). Use of an EEG-sleep-staging-derived measure to determine the probability of wakefulness for each minute revealed a novel metric to track changes in daytime sleepiness, which were consistent with the θ/α ratio, a known biomarker of drowsiness. The slopes of line-fits to both the log-transformed sleepiness score or log-transformed θ/α ratio correlated well to (inverse) MWT SOL for NT1 (R = 0.93 and R = 0.83, respectively) and NT2 (R = 0.97 and R = 0.84, respectively), suggesting that individuals with narcolepsy have increased sleepiness immediately after lights-off. These analyses demonstrate that novel EEG-based biomarkers can augment SOL as predictors of sleepiness and its response to treatment and provide a novel framework for the analysis of wake EEG in hypersomnia disorders.
PubMed: 38954525
DOI: 10.1093/sleep/zsae148 -
ELife Jul 2024Perceiving biological motion (BM) is crucial for human survival and social interaction. Many studies have reported impaired BM perception in autism spectrum disorder,...
Perceiving biological motion (BM) is crucial for human survival and social interaction. Many studies have reported impaired BM perception in autism spectrum disorder, which is characterised by deficits in social interaction. Children with attention deficit hyperactivity disorder (ADHD) often exhibit similar difficulties in social interaction. However, few studies have investigated BM perception in children with ADHD. Here, we compared differences in the ability to process local kinematic and global configurational cues, two fundamental abilities of BM perception, between typically developing and ADHD children. We further investigated the relationship between BM perception and social interaction skills measured using the Social Responsiveness Scale and examined the contributions of latent factors (e.g. sex, age, attention, and intelligence) to BM perception. The results revealed that children with ADHD exhibited atypical BM perception. Local and global BM processing showed distinct features. Local BM processing ability was related to social interaction skills, whereas global BM processing ability significantly improved with age. Critically, general BM perception (i.e. both local and global BM processing) may be affected by sustained attentional ability in children with ADHD. This relationship was primarily mediated by reasoning intelligence. These findings elucidate atypical BM perception in ADHD and the latent factors related to BM perception. Moreover, this study provides new evidence that BM perception is a hallmark of social cognition and advances our understanding of the potential roles of local and global processing in BM perception and social cognitive disorders.
Topics: Humans; Attention Deficit Disorder with Hyperactivity; Child; Male; Female; Motion Perception; Social Interaction; Adolescent; Attention
PubMed: 38954462
DOI: 10.7554/eLife.90313