Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 11 de 11
Filter
Add more filters










Publication year range
1.
Br J Health Psychol ; 29(1): 185-203, 2024 02.
Article in English | MEDLINE | ID: mdl-37787021

ABSTRACT

BACKGROUND: Bedtime procrastination, the volitional delay of going to bed without any external circumstances causing the delay, is linked to multiple indicators of inadequate sleep. Intervening to reduce bedtime procrastination may be an important avenue to improve sleep outcomes, yet the phenomenon remains poorly understood in populations at risk for bedtime procrastination. New career starters, those who have graduated from tertiary education and started a new full-time job within the past 12 months, may be susceptible to problematic bedtime procrastination and are at an opportune time for a 'fresh start' to change behaviour. AIMS: The objectives of this study were to understand how bedtime procrastination is experienced and perceived by new career starters, to identify the enablers and barriers to behaviour change in new career starters and to explore themes for future interventions. MATERIALS & METHODS: Data were collected through in-depth semi-structured interviews with 28 participants. RESULTS: Inductive thematic analysis was used to find seven themes: (1) negative feelings before and during bedtime procrastination; (2) wanting to versus knowing I shouldn't; (3) difficulty falling asleep; (4) influence of automatic processes; (5) consequences of bedtime procrastination; (6) lack of self-control and (7) technology captures late-night attention. Participants emphasised the need for me-time, self-negotiation to continue procrastinating and knowledge of the value of sleep. DISCUSSION & CONCLUSION: Findings suggest that bedtime procrastination involves both reflective and automatic cognitive processes. Future interventions would benefit from a dual-process approach, using cognitive and behavioural techniques to reduce bedtime procrastination.


Subject(s)
Procrastination , Self-Control , Humans , Sleep , Self-Control/psychology , Volition , Students/psychology
3.
Sleep Med Rev ; 66: 101697, 2022 12.
Article in English | MEDLINE | ID: mdl-36375334

ABSTRACT

Bedtime procrastination is defined as the volitional delay of going to bed, without any external circumstances causing the delay, and is associated with inadequate sleep. Alleviating bedtime procrastination is an important target for interventions promoting adequate sleep, yet the correlates of bedtime procrastination are poorly understood. This study examined (1) correlates of bedtime procrastination, and (2) strength and direction of the association between bedtime procrastination and sleep outcomes. Six databases (CINAHL, EMBASE, PsychINFO, PubMed, Scopus, Web of Science) were searched from inception to September 2021 against pre-determined eligibility criteria. Forty-three studies were included (GRADE = low). Meta-analysis revealed that bedtime procrastination had a moderate negative association with self-control (z = -0.39; CI: -0.45, -0.29) and a moderate positive association with evening chronotype (z = 0.43; CI: 0.32, 0.48). Furthermore, bedtime procrastination was moderately negatively associated with sleep duration (z = -0.31; CI: -0.37, -0.24), sleep quality (z = -0.35; CI: -0.42, -0.27) and moderately positively associated with daytime fatigue (z = 0.32; CI: 0.25, 0.38). Further high-quality studies are needed to identify causal relationships between bedtime procrastination and correlates, as well as bedtime procrastination and sleep. Future work will guide the development of interventions targeting bedtime procrastination for improved sleep outcomes. STUDY REGISTRATION: PROSPERO registration number CRD42021248891.


Subject(s)
Procrastination , Sleep Deprivation , Sleep , Humans , Chronotype
4.
Eur J Neurosci ; 51(1): 494-508, 2020 01.
Article in English | MEDLINE | ID: mdl-30295966

ABSTRACT

A key feature of circadian rhythms is the sleep/wake cycle. Sleep causes reduced responsiveness to the environment, which puts animals in a particularly vulnerable state; yet sleep has been conserved throughout evolution, indicating that it fulfils a vital purpose. A core function of sleep across species has not been identified, but substantial advances in sleep research have been made in recent years using the genetically tractable model organism, Drosophila melanogaster. This review describes the universality of sleep, the regulation of sleep, and current theories on the function of sleep, highlighting a historical and often overlooked theory called the Free Radical Flux Theory of Sleep. Additionally, we summarize our recent work with short-sleeping Drosophila mutants and other genetic and pharmacological tools for manipulating sleep which supports an antioxidant theory of sleep and demonstrates a bi-directional relationship between sleep and oxidative stress.


Subject(s)
Drosophila Proteins , Drosophila melanogaster , Animals , Circadian Rhythm , Drosophila , Sleep
5.
PLoS Biol ; 16(7): e2005206, 2018 07.
Article in English | MEDLINE | ID: mdl-30001323

ABSTRACT

Although sleep appears to be broadly conserved in animals, the physiological functions of sleep remain unclear. In this study, we sought to identify a physiological defect common to a diverse group of short-sleeping Drosophila mutants, which might provide insight into the function and regulation of sleep. We found that these short-sleeping mutants share a common phenotype of sensitivity to acute oxidative stress, exhibiting shorter survival times than controls. We further showed that increasing sleep in wild-type flies using genetic or pharmacological approaches increases survival after oxidative challenge. Moreover, reducing oxidative stress in the neurons of wild-type flies by overexpression of antioxidant genes reduces the amount of sleep. Together, these results support the hypothesis that a key function of sleep is to defend against oxidative stress and also point to a reciprocal role for reactive oxygen species (ROS) in neurons in the regulation of sleep.


Subject(s)
Drosophila melanogaster/physiology , Oxidative Stress , Sleep/physiology , Animals , Antioxidants/metabolism , Drosophila Proteins/metabolism , Drosophila melanogaster/genetics , Gene Expression Regulation , Gene Knockdown Techniques , Immunity , Longevity , Mutation/genetics , Neurons/metabolism , Oxidative Stress/genetics , RNA Interference , Reactive Oxygen Species/metabolism
6.
J Cell Biol ; 216(3): 595-605, 2017 03 06.
Article in English | MEDLINE | ID: mdl-28223318

ABSTRACT

Fragile X syndrome, the most common known monogenic cause of autism, results from the loss of FMR1, a conserved, ubiquitously expressed RNA-binding protein. Recent evidence suggests that Fragile X syndrome and other types of autism are associated with immune system defects. We found that Drosophila melanogaster Fmr1 mutants exhibit increased sensitivity to bacterial infection and decreased phagocytosis of bacteria by systemic immune cells. Using tissue-specific RNAi-mediated knockdown, we showed that Fmr1 plays a cell-autonomous role in the phagocytosis of bacteria. Fmr1 mutants also exhibit delays in two processes that require phagocytosis by glial cells, the immune cells in the brain: neuronal clearance after injury in adults and the development of the mushroom body, a brain structure required for learning and memory. Delayed neuronal clearance is associated with reduced recruitment of activated glia to the site of injury. These results suggest a previously unrecognized role for Fmr1 in regulating the activation of phagocytic immune cells both in the body and the brain.


Subject(s)
Drosophila melanogaster/immunology , Fragile X Syndrome/immunology , Immunity, Innate/immunology , Phagocytosis/immunology , Animals , Brain/immunology , Brain/metabolism , Disease Models, Animal , Drosophila Proteins/immunology , Drosophila Proteins/metabolism , Drosophila melanogaster/metabolism , Fragile X Mental Retardation Protein/metabolism , Fragile X Syndrome/metabolism , Learning/physiology , Male , Memory/physiology , Mushroom Bodies/immunology , Mushroom Bodies/metabolism , Neuroglia/immunology , Neuroglia/metabolism , Neurons/immunology , Neurons/metabolism , RNA Interference/immunology , RNA-Binding Proteins/immunology , RNA-Binding Proteins/metabolism
8.
Curr Biol ; 26(2): 184-194, 2016 Jan 25.
Article in English | MEDLINE | ID: mdl-26748856

ABSTRACT

Most metazoans undergo dynamic, circadian-regulated changes in behavior and physiology. Currently, it is unknown how circadian-regulated behavior impacts immunity against infection. Two broad categories of defense against bacterial infection are resistance, control of microbial growth, and tolerance, control of the pathogenic effects of infection. Our study of behaviorally arrhythmic Drosophila circadian period mutants identified a novel link between nutrient intake and tolerance of infection with B. cepacia, a bacterial pathogen of rising importance in hospital-acquired infections. We found that infection tolerance in wild-type animals is stimulated by acute exposure to dietary glucose and amino acids. Glucose-stimulated tolerance was induced by feeding or direct injection; injections revealed a narrow window for glucose-stimulated tolerance. In contrast, amino acids stimulated tolerance only when ingested. We investigated the role of a known amino-acid-sensing pathway, the TOR (Target of Rapamycin) pathway, in immunity. TORC1 is circadian regulated and inhibition of TORC1 decreased resistance, as in vertebrates. Surprisingly, inhibition of the less well-characterized TOR complex 2 (TORC2) dramatically increased survival, through both resistance and tolerance mechanisms. This work suggests that dietary intake on the day of infection by B. cepacia can make a significant difference in long-term survival. We further demonstrate that TOR signaling mediates both resistance and tolerance of infection and identify TORC2 as a novel potential therapeutic target for increasing survival of infection.


Subject(s)
Drosophila Proteins/metabolism , Drosophila melanogaster/metabolism , Feeding Behavior , Period Circadian Proteins/metabolism , Signal Transduction , Amino Acids/metabolism , Animals , Drosophila Proteins/genetics , Drosophila melanogaster/genetics , Feeding Behavior/drug effects , Feeding Behavior/physiology , Mechanistic Target of Rapamycin Complex 1 , Mechanistic Target of Rapamycin Complex 2 , Multiprotein Complexes/metabolism , Period Circadian Proteins/genetics , Phosphorylation , Signal Transduction/drug effects , Sirolimus/pharmacology , TOR Serine-Threonine Kinases/metabolism
9.
Ophthalmic Genet ; 26(2): 77-84, 2005 Jun.
Article in English | MEDLINE | ID: mdl-16020310

ABSTRACT

OBJECTIVE: To describe the clinical and electrophysiological characterization of four family members from three generations who have X-linked infantile periodic alternating nystagmus (XIPAN). METHODS: Complete clinical ophthalmological evaluation, pedigree analysis, electroretinograms (ERG), eye movement recordings (EMR), color vision, and fundus photography were performed on all subjects. RESULTS: Three males in two generations and one female were examined. Clinical examinations showed a jerk/pendular nystagmus with a latent component, strabismus, and a significant refractive error in the three affected males, while the female had only myopic astigmatism. ERG, color contrast, and fundus examinations were normal in all four family members. All four family members showed EMR abnormalities with infantile jerk/dual jerk and pendular nystagmus waveforms. The female had nystagmus present on EMR only and all patients showed (a)periodicity to their nystagmus. CONCLUSIONS: In this family with no other congenital visual sensory system disease, affected males had obvious periodic alternating nystagmus, strabismus, and refractive errors, while the female had clinically "silent" periodic nystagmus that is probably a marker for the carrier state.


Subject(s)
Chromosomes, Human, X/genetics , Eye Movements/physiology , Genetic Diseases, X-Linked/genetics , Genetic Linkage , Nystagmus, Pathologic/genetics , Adult , Aged , Child , Depth Perception/physiology , Electroretinography , Female , Humans , Male , Middle Aged , Nystagmus, Pathologic/congenital , Nystagmus, Pathologic/pathology , Pedigree , Visual Acuity
10.
Am J Ophthalmol ; 139(4): 716-8, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15808174

ABSTRACT

PURPOSE: We report a new method of measuring visual function in patients with INS by demonstrating the effects of eccentric gaze and forced time restriction on optotype recognition. DESIGN: Cross-sectional, comparative case-series. METHODS: No-time-restricted acuity (NTRA) and time-restricted acuity (TRA) for 19 patients and 18 controls were measured at multiple horizontal gaze angles. RESULTS: INS patients showed a significant lower visual acuity than controls (P < 0.0001). The TRA were significantly decreased in most gaze positions relative to NTRA in INS patients (P = 0.03) while there were no difference among controls. About half of the INS patients showed that their best visual acuity was gaze dependent, matching the preferred head posture in both NRTA and TRA paradigms. CONCLUSIONS: Gaze-dependent visual acuity tested with and without time restriction may be a useful measure of visual function in INS patients and could be used in interventional clinical trials.


Subject(s)
Nystagmus, Congenital/physiopathology , Saccades/physiology , Visual Acuity/physiology , Adult , Cross-Sectional Studies , Female , Humans , Male , Posture , Syndrome , Time Factors , Vision Tests/methods
11.
Am J Ophthalmol ; 138(6): 978-87, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15629289

ABSTRACT

PURPOSE: The purpose of this report is to characterize the clinical and electrophysiological effects of extraocular muscle surgery in 15 patients with oculo-cutaneous albinism (OCA) and infantile nystagmus syndrome (INS). Our hypothesis is that surgery on the extraocular muscles of patients with OCA and INS changes their nystagmus and their visual function. DESIGN: Interventional, prospective, cohort, noncomparative case series. METHODS: All 15 patients had surgery on all four virgin horizontal recti; three for strabismus alone, three for nystagmus alone, five for an eccentric gaze null zone alone, and four for an eccentric gaze null zone plus strabismus. All patients have been followed for at least six months. All 15 patients had the subjective outcome measure of pre- and postoperative binocular best optically corrected acuity (BBOCA). Objective outcome measures included anomalous head posture (AHP) in nine patients, eye movement recording measures of expanded nystagmus acuity function (NAFX) in 10 patients, null zone position (NUZP) and null zone width (NUZW) in 10 patients, and foveation time (FOV) in nine patients. RESULTS: The results are summarized as follows; BBOCA increased 0.1 LogMar or greater in 14 of 15 patients. In those operated on for an AHP with or without associated strabismus the AHP improved significantly (P < .01 for all). The NAFX, NUZP, NUZW, and FOV measured from eye movement recordings showed persistent, significant increases in all patients (P < .01 for all). CONCLUSIONS: This report adds to the evidence that surgery on the extraocular muscles in patients with INS has independent neurologic and visual results.


Subject(s)
Albinism, Oculocutaneous/surgery , Nystagmus, Congenital/surgery , Oculomotor Muscles/surgery , Adolescent , Adult , Albinism, Oculocutaneous/complications , Albinism, Oculocutaneous/physiopathology , Child , Child, Preschool , Electrophysiology , Eye Movements/physiology , Female , Head Movements/physiology , Humans , Male , Nystagmus, Congenital/complications , Nystagmus, Congenital/physiopathology , Oculomotor Muscles/physiopathology , Ophthalmologic Surgical Procedures , Posture , Prospective Studies , Syndrome , Visual Acuity/physiology
SELECTION OF CITATIONS
SEARCH DETAIL
...