Search Results (350)

This study aims to provide a comprehensive overview of psychological distress among medical students in Spain, a growing concern given the high prevalence rates of anxiety, depression, and burnout reported across multiple medical schools and universities. To assess the scope and key characteristics of this phenomenon, a thorough literature search was conducted in the PubMed, ProQuest, and Web of Science (WoS) databases. Studies published between 2010 and 2024 in peer-reviewed scientific journals, written in English or Spanish, and specifically focused on medical students enrolled in Spanish universities were considered for inclusion. A total of 14 studies were analysed. The findings indicate that psychological distress often emerges early in medical training and tends to intensify as students progress academically. Female medical students are consistently more affected, as most of the studies reviewed indicate that they exhibit higher levels of depressive symptoms, trait anxiety, and perceived stress. Some research also suggests greater levels of burnout among female students compared to their male peers. Key contributing factors include academic overload and dissatisfaction, sleep deprivation, and the use of maladaptive coping strategies. Although awareness of the issue is increasing, available evidence suggests that institutional responses remain limited, and that only a small number of universities have implemented structured mental health programmes. Overall, the results underscore the urgent need for institutional reforms in Spanish medical education to safeguard students’ mental wellbeing. Key priorities include revising curricula, implementing structured emotional support programmes, and ensuring accessible services—requiring coordinated, long-term commitment across academic, healthcare, and policy sectors. Future research should explore longitudinal trends and the effectiveness of targeted interventions. Full article

Sleep is crucial to overall health and plays a significant role in skin function. While the circadian rhythm has been extensively researched for its impact on the body’s optimal functioning, the skin also possesses an independent circadian system that serves many important functions. Sleep disruptions or deprivation can significantly affect skin conditions, by compromising the skin barrier and impairing processes such as collagen production, cellular repair, and wound healing. Given the commonality of sleep disturbances, it is crucial to understand the connection between sleep, circadian regulation, and skin health. This is particularly important in understudied populations, such as those with occupational sleep disruption and individuals with hormone-related conditions like PCOS and menopause. Bidirectional relationships have been established between sleep and several inflammatory skin conditions, including atopic dermatitis, psoriasis, rosacea, and hidradenitis suppurativa. While acne is influenced by sleep, the reverse relationship, how acne affects sleep quality, has not been well established. Chronic sleep disruption can increase cortisol levels and oxidative stress, both of which contribute to skin aging and the progression of autoimmune skin conditions, including systemic lupus erythematosus. As sleep is a modifiable risk factor, it is crucial to consider therapeutic options and interventions to prevent or alleviate skin conditions. This review discusses various therapeutic approaches, including melatonin, L-Theanine, Magnesium-L-threonate, Inositol, Cinnamomi cortex, nervous system regulation, and proper sleep hygiene. These therapeutic options have been studied for their impact on sleep, and importantly, several have been evaluated for their utility as adjuncts for treating skin conditions. Overall, the relationship between sleep and skin health is clear, and incorporating sleep-focused therapeutic interventions offers potential to improve both sleep quality and skin health in individuals with a variety of skin conditions. Full article

Short sleep has been linked to overweight, possibly via alterations in appetite-regulating hormones, but findings are inconsistent. Sex differences may contribute to this variability. This systematic review examines whether sex modifies the hormonal response to sleep curtailment. PubMed, Embase, Cochrane, CINAHL, and PsycINFO were searched for English-language experimental studies published before December 2024. Included studies assessed at least one appetite-regulating hormone and presented sex-specific analyses. Studies involving health conditions affecting sleep, circadian misalignment, or additional interventions were excluded. Risk of bias was assessed using the Revised Cochrane Risk-of-Bias tool (RoB 2). Eight studies (n = 302 participants) met inclusion criteria. A narrative synthesis of the findings was conducted for each hormone separately to explore potential differences in their response to sleep restriction. Some sex-related variations in hormonal response to sleep restriction have been observed for leptin (four studies, n = 232), insulin (three studies, n = 56), glucagon-like peptide-1 (one study, n = 27), ghrelin (three studies, n = 87), adiponectin (two studies, n = 71) and thyroxine (two studies, n = 41). However, findings were inconsistent with no clear patterns. No sex-related differences were found for glucagon or PYY, though data were limited. Findings suggest sex may influence hormonal responses to sleep restriction, but inconsistencies highlight the need to consider factors such as BMI and energy balance. Well-controlled, adequately powered studies are needed to clarify these effects. Full article

Transcranial direct current stimulation (tDCS) can modulate cortical excitability in a polarity-specific manner, yet identical protocols often produce inconsistent outcomes across sessions or individuals. This narrative review proposes that much of this variability arises from the brain’s intrinsic temporal landscape. Integrating evidence from chronobiology, sleep research, and non-invasive brain stimulation, we argue that tDCS produces reliable, polarity-specific after-effects only within a circadian–homeostatic “window of efficacy”. On the circadian (Process C) axis, intrinsic alertness, membrane depolarisation, and glutamatergic gain rise in the late biological morning and early evening, whereas pre-dawn phases are marked by reduced excitability and heightened inhibition. On the homeostatic (Process S) axis, consolidated sleep renormalises synaptic weights, widening the capacity for further potentiation, whereas prolonged wakefulness saturates plasticity and can even reverse the usual anodal/cathodal polarity rules. Human stimulation studies mirror this two-process fingerprint: sleep deprivation abolishes anodal long-term-potentiation-like effects and converts cathodal inhibition into facilitation, while stimulating at each participant’s chronotype-aligned (phase-aligned) peak time amplifies and prolongs after-effects even under equal sleep pressure. From these observations we derive practical recommendations: (i) schedule excitatory tDCS after restorative sleep and near the individual wake-maintenance zone; (ii) avoid sessions at high sleep pressure or circadian troughs; (iii) log melatonin phase, chronotype, recent sleep and, where feasible, core temperature; and (iv) consider mild pre-heating or time-restricted feeding as physiological primers. By viewing Borbély’s two-process model and allied metabolic clocks as adjustable knobs for plasticity engineering, this review provides a conceptual scaffold for personalised, time-sensitive tDCS protocols that could improve reproducibility in research and therapeutic gain in the clinic. Full article

Background/Objectives: The glymphatic system plays a crucial role in clearing brain metabolic waste, and its dysfunction has been correlated to various neurological disorders. The Diffusion Tensor Imaging Analysis Along the Perivascular Space (DTI-ALPS) index has been proposed as a non-invasive marker of glymphatic function by measuring diffusivity along perivascular spaces; however, its sensitivity to sleep-related changes in glymphatic activity has not yet been validated. This study aimed to evaluate the feasibility of using the DTI-ALPS index as a quantitative marker of dynamic glymphatic activity during sleep. Methods: Diffusion tensor imaging (DTI) data were obtained from 12 healthy male participants (age = 24.44 ± 2.5 years; Pittsburgh Sleep Quality Index (PSQI) < 5), once while awake and 16 times during sleep, following 24 h sleep deprivation and administration of 10 mg zolpidem. Simultaneous MR-compatible electroencephalography was used to determine whether the subject was asleep or awake. DTI preprocessing included eddy current correction and tensor fitting. The DTI-ALPS index was calculated from nine regions of interest in projection and association areas aligned to standard space. The final analysis included nine participants (age = 24.56 ± 2.74 years; PSQI < 5) who maintained a continuous sleep state for 1 h without awakening. Results: Among nine ROI pairs, three showed significant increases in the DTI-ALPS index during sleep compared to wakefulness (Friedman test; p = 0.027, 0.029, 0.034). These ROIs showed changes at 14, 19, and 25 min after sleep induction, with FDR-corrected p-values of 0.024, 0.018, and 0.018, respectively. Conclusions: This study demonstrated a statistically significant increase in the DTI-ALPS index within 30 min after sleep induction through time-series DTI analysis during wakefulness and sleep, supporting its potential as a biomarker reflecting glymphatic activity. Full article

Sleep deprivation impairs immune function, and melatonin has emerged as a key mediator in this process. This narrative review analyzes 50 studies published between 2000 and 2025 to determine the extent to which reduced melatonin synthesis contributes to immune dysregulation. Consistent sleep loss lowers melatonin levels, which correlates with elevated proinflammatory cytokines (e.g., IL-6 and TNF-α), increased oxidative stress, and reduced immune cell activity, including that of natural killer (NK) cells and CD4+ lymphocytes. Melatonin regulates immune pathways, including NF-κB signaling. It also supports mitochondrial health and helps maintain gut barrier integrity. These effects are particularly relevant in vulnerable populations, including older adults and shift workers. Experimental findings also highlight melatonin’s therapeutic potential in infections like SARS-CoV-2, where it modulates inflammatory responses and viral entry mechanisms. Despite the heterogeneity of study methodologies, a consistent correlation emerges between circadian disruption, melatonin suppression, and immune imbalance. These findings underscore melatonin’s dual role as a chronobiotic and immunomodulator. Addressing sleep loss and considering melatonin-based interventions may help restore immune homeostasis. More clinical trials are needed to determine the best dosing, long-term efficacy, and population-specific strategies for supplementation. Promoting healthy sleep is crucial for preventing chronic inflammation and diseases associated with immune dysfunction. Full article

Morningness-eveningness is usually assessed as either a trait or a state using either a morning–evening preference scale or sleep timing reported for free days, respectively. These assessments were implemented in numerous studies exploring the associations between morningness-eveningness and health, mood, and sleep problems. Evening types almost always had more problems than morning types. We examined these associations in university students with conflicting results of trait and state assessments of morningness-eveningness and tried to confirm their chronotype using a multidimensional chronotyping approach that recognizes four types other than morning and evening (lethargic, vigilant, napping, and afternoon). The conflicting trait and state assessments of morningness-eveningness were found in 141 of 1582 students. Multidimensional chronotyping supported morningness of morning types with late weekend sleep timing, and the associations with health, mood, and sleep problems resembled the associations of other morning types (i.e., these associations persisted despite late sleep timing). In contrast, evening types with early weekend sleep timing were more likely classified as lethargic or napping types rather than evening types. They did not resemble evening types in their associations with health, mood, and sleep problems (i.e., early sleep timing did not change these associations). Model-based simulations of the sleep–wake cycles of students with conflicting trait and state assessments suggested that their bedtimes cannot be solely determined by their biological clocks. On weekdays or weekends, mind-bedtime procrastination can lead to missing the bedtime signal from their biological clocks (i.e., self-deprivation of sleep or, in other words, voluntary prolongation of the wake phase of the sleep–wake cycle). Full article

Glutamate and dopamine receptors play a crucial role in regulating synaptic plasticity throughout the sleep–wake cycle. These receptors form various heterocomplexes in synaptic areas; however, the role of this protein interactome in sleep–wake cycles remains unclear. Co-immunoprecipitation experiments were conducted to observe the complexation of the NMDA glutamate receptor (NMDAR) subunits GluN2A and GluN2B, metabotropic glutamate receptors mGluR1/5, and dopamine receptors (D1R and D2R) with the scaffold protein Homer in the synaptic membranes of the hippocampus after six hours of sleep deprivation (SD) in rats. Our findings indicate that the level of Homer in the GluN2A/mGluR1/D1R interactome decreased during SD, while the content of Homer remained unchanged in the GluN2B/mGluR1/D2R heterocomplex. Moreover, Homer immunoprecipitated a reduced amount of inositol trisphosphate receptor (IP3R) in the microsomal and synaptic fractions, confirming the dissociation of the ternary supercomplex Homer/mGluR1/IP3R during SD. Additionally, our findings indicate that SD increases the synaptic content of the AMPA receptor (AMPAR) subunit GluA1. Unlike AMPAR, NMDAR subunits in synaptic membranes do not undergo significant changes. Furthermore, the G-to-F actin ratio decreases during SD. Changes in the assembly of actin filaments occur due to the dephosphorylation of cofilin. These results suggest that SD causes the dissociation of the GluN2A/mGluR1/D1R/Homer/IP3R heterocomplex in synaptic and endoplasmic membranes. Full article

Background: Sleep is a fundamental component of health, and deprivation has been linked to numerous adverse outcomes, including reduced academic and occupational performance, greater risk of accidents, and increased susceptibility to chronic diseases and premature mortality. Dietary and lifestyle behaviors are increasingly recognized as key determinants of sleep quality. Women are particularly susceptible to sleep disturbances due to hormonal fluctuations and psychosocial factors. However, women remain underrepresented in sleep research. This study aims to examine the associations between sleep quality, nutrition, and lifestyle in a large cohort of Spanish women. Methods: A cross-sectional study was conducted with 785 women aged 18–64. Participants completed the Pittsburgh Sleep Quality Index (PSQI) and the NutSo-HH questionnaire on dietary and lifestyle behaviors. Descriptive analyses, correlation matrices, Gaussian Graphical Models, and Principal Component Analyses were used to assess relationships between variables. Results: More than half of the participants rated their sleep quality as good or very good, although over 30% experienced frequent nighttime awakenings. Poor sleep quality was significantly associated with higher alcohol consumption, lower vegetable and white fish intake, and lower levels of physical activity. Diets rich in ultra-processed foods correlated moderately with subjective poor sleep and daytime dysfunction. However, no strong associations were found between stimulant consumption, late meals, or dietary patterns (e.g., Mediterranean diet) and sleep. Self-perceived health emerged as a protective factor, while nocturnal lifestyles were linked to longer sleep latency and fragmented sleep. Conclusions: In adult women, better sleep quality is linked to healthy dietary choices, regular physical activity, and a positive perception of general health. In contrast, alcohol use and irregular lifestyles are associated with poor sleep. Individual variability and cultural adaptation may moderate the impact of some traditionally harmful behaviors. Personalized, multidimensional interventions are recommended for promoting sleep health in women. Full article

Work-related well-being is an important research topic, as it is linked to various aspects of individuals’ lives, including job performance. To measure it effectively, unobtrusive sensors are desirable to minimize the burden on employees. Because there is a lack of consensus on the definitions of well-being in the psychological literature in terms of its dimensions, our work begins by proposing a conceptualization of well-being based on the refined definition of health provided by the World Health Organization. We focus on reviewing the existing literature on the unobtrusive measurement of well-being. In our literature review, we focus on affect, engagement, fatigue, stress, sleep deprivation, physical comfort, and social interactions. Our initial search resulted in a total of 644 studies, from which we then reviewed 35, revealing a variety of behavioral markers such as facial expressions, posture, eye movements, and speech. The most commonly used sensory devices were red, green, and blue (RGB) cameras, followed by microphones and smartphones. The methods capture a variety of behavioral markers, the most common being body movement, facial expressions, and posture. Our work serves as an investigation into various unobtrusive measuring methods applicable to the workplace context, aiming to foster a more employee-centric approach to the measurement of well-being and to emphasize its affective component. Full article

The widespread adoption of mobile work, driven by advancements in information and communication technology, has increasingly blurred the boundaries between work and personal life. This phenomenon can increase job stress, potentially leading to sleep deprivation, which affects not only employees’ health and well-being but also organizational performance. Grounded in Conservation of Resources theory, this study examines the pathway through which mWork contributes to sleep deprivation, focusing on the mediating role of job stress, and investigates the moderating effects of gender and number of children on this relationship. Data were collected using a stratified random sampling method across three waves with 4-week intervals, involving 325 employees in South Korea engaged in diverse occupations, including the administrative, technical, service, and sales sectors. The findings reveal that mWork increases sleep deprivation through the mediation of job stress. Furthermore, the relationship between mWork and job stress was found to vary depending on gender and number of children, with stronger moderating effects observed among women and employees with children. This study underscores the need for organizations to develop tailored management strategies that address the unique challenges posed by mWork, taking particular note of employees’ gender and family responsibilities. By mitigating the negative effects of mWork on job stress and sleep deprivation, organizations can enhance employee well-being and promote sustainable long-term performance. Full article

Introduction: For patients in intensive care units, the Richards–Campbell Sleep Questionnaire (RCSQ) seems to be a useful tool for assessing sleep quality. However, its application in the Moroccan medical context could be limited due to the lack of a dialectal Arabic version for Morocco. This study’s objective was to translate and validate the RCSQ into Arabic for Moroccan speakers. Patients and methods: For this investigation, a cross-sectional design was adopted. The RCSQ was translated and validated into Arabic for Morocco in accordance with the recommendations. For every scale, psychometric properties were computed. The Cronbach’s α coefficient was utilized to evaluate the internal consistency of multi-item measures. Results: The study involved 224 patients, whose mean age was 47 ± 18.3 years. The RCSQ’s internal consistency, or Cronbach’s alpha, was computed, and all dimensions showed good reliability over the 0.92 (0.894–0.983) level. The items demonstrated good reliability and validity, with correlation values larger than 0.4, according to the data. Conclusion: The RCSQ translated into Arabic for Morocco appears to have good psychometric qualities, making it useful for assessing the quality of sleep of patients in intensive care units within Moroccan healthcare settings. Full article

Introduction: Short sleep duration has been implicated in an increased body mass index (BMI), potentially through disruptions in appetite-regulating hormones, such as leptin and ghrelin. Methods: This systematic review and meta-analysis aimed to examine the effects of sleep deprivation on circulating levels of these hunger hormones and their possible role in obesity. Six randomized controlled trials (RCTs) involving 141 participants were included in the analysis, with sleep deprivation typically manipulated through restricting sleep by 4–5 h or keeping participants awake for 24 h. Data on leptin and ghrelin levels were extracted from blood samples, and statistical analysis was conducted using a random-effects model. Results: The results revealed no significant changes in ghrelin (SMD: −0.27, 95% CI: −1.00, 0.46, p = 0.4712) or leptin (SMD: 0.10, 95% CI: −0.22, 0.42, p = 0.5266) levels following sleep deprivation, contrary to prior studies suggesting a link between sleep loss and altered appetite regulation. Significant heterogeneity was observed for ghrelin levels (I² = 83.83%, p < 0.001), but not for leptin (I² = 21.86%, p = 0.4049). Variations in study design, including differences in blood sampling timing and participant BMI, may explain this variability. Conclusions: These findings suggest that, at least in the short term, sleep deprivation does not consistently affect leptin and ghrelin levels. Given the complex relationship between sleep and appetite regulation, future research should focus on standardized study designs, participant characteristics, and more precise measurements to further explore these mechanisms. Full article

Sleep deprivation (SD) is known to impair cognitive functions, and its effect on vigilance and concentration has been explored extensively. However, its effect on the decision-making ability has been researched to a lesser extent. With varying methodologies and conflicting findings in the literature, the effect of SD on decision-making remains complex and inconsistent. Given the critical implications for fields where decision-making is essential, such as medicine, understanding the impact of SD on this cognitive process is crucial. This scoping review aimed to map the existing literature on the effects of SD on decision-making, identify research trends, and highlight inconsistencies to provide implications for practice and research. The review was conducted following PRISMA-ScR guidelines. Databases searched include APA Psych, Web of Science, Scopus, Academic Search Complete, and PubMed. Inclusion criteria focused on peer-reviewed studies from 2014 onward, exploring the impact of SD on decision-making across various tasks and designs. The final selection included 25 articles, representing 2276 participants. The review may suggest that SD, whether partial or total, impairs decision-making ability, with many studies reporting increased risky decisions. The severity of impairment varied based on the type of decision-making task and the duration of SD. However, a few studies reported insignificant effects, particularly in economic decision-making tasks. Moderating factors, such as gender and the origin of sleep loss (voluntary vs. involuntary), were also identified as influential. Sleep deprivation commonly impairs the decision-making ability, with significant implications for high-stakes professions. However, the variability in findings suggests a need for further research into the moderating factors. The review underscores the importance of adequate sleep for cognitive function and the need for policies that mitigate the risks of SD in critical decision-making environments. Full article

Sleep is essential for physical and mental health, playing a critical role in memory consolidation, behavioral stability, and the regulation of immune and metabolic functions. The incidence of sleep disorders, particularly sleep deprivation (SD), increases with age and is prevalent in neurodegenerative and psychiatric disorders such as Alzheimer’s disease (AD). Nearly 40% of AD patients experience significant chronic sleep impairments. The clinical distinction between late-life sleep disorders and AD is often challenging due to overlapping symptoms, including cognitive decline and behavioral impairments. Although the exact causal relationship between SD and AD remains complex and multifaceted, strong evidence suggests a bidirectional link, with AD patients frequently exhibiting disrupted sleep architecture, reduced slow-wave activity, and shorter total sleep duration. On a pathophysiological level, SD contributes to neuroinflammation, amyloid-β plaque deposition, and tau tangles, which are key features of AD. Current treatments, such as sedatives and antidepressants, often have limitations, including inconsistent efficacy, dependency risks, and poor long-term outcomes/recurrence, highlighting the need for safer and more effective alternatives. This review examines the interplay between SD and AD and proposes omega (n)-3 fatty acids (FAs) as a potential therapeutic intervention. Preclinical and clinical studies suggest that n-3 supplementation may improve sleep onset/quality, reduce neuroinflammation, support synaptic function, and decrease amyloid-β aggregation, thereby alleviating early AD-related neurological changes. Given their safety profile and neuroprotective effects, n-3 FAs represent a promising strategy for managing the comorbidity of sleep disorders in AD. Full article