A5023887512- Circadian rhythm and melatonin
- Sleep and Wakefulness Research
- Photoreceptor and optogenetics research
- Neurobiology and Insect Physiology Research
- Sleep and related disorders
- Spaceflight effects on biology
- Neuroendocrine regulation and behavior
- Dietary Effects on Health
- Light effects on plants
- Adipose Tissue and Metabolism
- Neuroscience and Neuropharmacology Research
- Neuroscience of respiration and sleep
- Stress Responses and Cortisol
- Heart Rate Variability and Autonomic Control
- Biochemical effects in animals
- Neurotransmitter Receptor Influence on Behavior
- Neuroinflammation and Neurodegeneration Mechanisms
- Alzheimer's disease research and treatments
- Receptor Mechanisms and Signaling
- Behavioral Health and Interventions
- Psychological and Temporal Perspectives Research
- Heavy Metal Exposure and Toxicity
- Impact of Light on Environment and Health
- Genetics, Aging, and Longevity in Model Organisms
- Neural dynamics and brain function
University of Calgary
2014-2024
Allen Institute for Brain Science
2013-2019
University of Pennsylvania Health System
2014
Leiden University Medical Center
2012
Institute of Psychology
2009
Columbia University
2003-2007
Simon Fraser University
1998-2002
Dalhousie University
1995
Our study examined whether mindfulness-based stress reduction (MBSR) is noninferior to cognitive behavioral therapy for insomnia (CBT-I) the treatment of in patients with cancer.This was a randomized, partially blinded, noninferiority trial involving cancer recruited from tertiary center Calgary, Alberta, Canada, September 2008 March 2011. Assessments were conducted at baseline, after program, and 3 months follow-up. The margin 4 points measured by Insomnia Severity Index. Sleep diaries...
Circadian rhythms in several species can be phase-shifted by procedures that stimulate locomotor activity (“exercise”) during the usual sleep period. The role of arousal or loss, independent activity, this effect has not been adequately resolved. We show here, using deprivation procedure gentle handling, comparably large phase shifts (up to 240 min advances) rest–activity cycle induced Syrian hamsters 3 hr behavioral arousal, with minimal locomotion, beginning 6 before active Horizontal...
We studied the influence on circadian rhythms of peptides that have been reported to be colocalized in suprachiasmatic nucleus (SCN) neurons. Gastrin-releasing peptide (GRP1-27), histidine isoleucine (PHI), and vasoactive intestinal polypeptide (VIP) were microinjected into region Syrian hamsters free running under three different constant lighting conditions. All injections caused phase-dependent phase shifts hamster locomotor activity which unaffected by GRP1-27 (150 pmol) large delays...
Seizures are often followed by sensory, cognitive or motor impairments during the postictal phase that show striking similarity to transient hypoxic/ischemic attacks. Here we seizures result in a severe hypoxic attack confined period. We measured brain oxygenation localized areas from freely-moving rodents and discovered event (pO2 < 10 mmHg) after termination of seizures. This lasted over an hour, is mediated hypoperfusion, generalizes people with epilepsy, attenuated inhibiting...
Abstract In mammals, the suprachiasmatic nuclei (SCN) of hypothalamus control endogenous circadian rhythms and entrainment to environment. A core SCN region calbindin (CalB)‐containing cells is retinorecipient therein lack rhythmic expression clock genes electrical activity. The surrounded by a ‘shell’ oscillator cells. present experiments, we studied spatial arrangement examining temporal patterns canonical Per1, Per2 vasopressin mRNA, clock‐controlled gene. Surprisingly, in shell,...
Circadian rhythms in mammals are regulated by a system of endogenous circadian oscillators (clock cells) the brain and most peripheral organs tissues. One group clock cells hypothalamic SCN (suprachiasmatic nuclei) functions as pacemaker for co-ordinating timing elsewhere body. This master can be reset entrained daily LD (light–dark) cycles thereby also serves to interface internal with external time, ensuring an appropriate alignment behavioural physiological solar day. Two features...
Circadian rhythms are regulated by the suprachiasmatic nucleus (SCN), a small structure at base of hypothalamus. While light effects on SCN well established, little is known behavioral effects. This study elucidates direct modulating action activity use in vivo electrophysiology recordings, assessments general locomotor behavior, and video-tracking mice. The results show suppression neuronal spontaneous magnitude being dependent intensity, duration type activity. was moderate (32% circadian...
Fetal BPA exposure, even below safe regulatory limits, disrupts the developing hypothalamus and affects behavior activity.
Abstract Healthy sleep supports robust development of the brain and behavior. Modern society presents a host challenges that can impair disrupt critical circadian rhythms reinforce optimal physiological functioning, including proper timing consolidation sleep. While acute effects inadequate disrupted are being defined, adverse developmental consequences understudied. Here, we exposed mice to disrupting light–dark cycles from birth until weaning demonstrate such exposure has impacts on...
Endogenous depression is often accompanied by alterations in core parameters of circadian rhythms, and antidepressant treatments, including serotonergic drugs, sleep deprivation exercise, alter phase or period humans animal models. Antidepressants may act part through the system, behavioral antidepressants a common path to clock. This review evaluates evidence from models that serotonin (5-HT) mediates phase-shifting effects stimuli on rhythms. In rodents, 'exercise' stimulated during rest...
The suprachiasmatic nuclei (SCN) control circadian oscillations of physiology and behavior. Measurements electrical activity gene expression indicate that these heterogeneous structures are composed both rhythmic nonrhythmic cells. A fundamental question with regard to the organization system is how SCN achieve a coherent output while their constituent independent cellular oscillators express wide range periods. Previously, consensus individual had been attributed coupling among authors...
Recent literature suggests that sleep deprivation has a general stimulatory effect on the central serotonergic system. Herein we report in hamsters, induced by gentle handling for 3 h under dim red light at midday stimulates serotonin release suprachiasmatic nuclei as much 171%. Basal levels of 5-HT are re-established within 1 after cessation treatment. Sleep also evokes phase advances circadian activity rhythm averaging 2 h. When is undertaken bright light, stimulated, but phase-shifting...
The circadian clock located in the mammalian suprachiasmatic nucleus (SCN) exhibits substantial heterogeneity both its neurochemical and functional organization, with retinal input oscillatory timekeeping functions segregated to different regions within nucleus. Although it is clear that photic information must be relayed from directly retinorecipient cells population of oscillator nucleus, intra-SCN signal (or signals) underlying such communication has yet identified. Gastrin-releasing...
Serotonin (5-HT) is thought to play a role in regulating nonphotic phase shifts and modulating photic of the mammalian circadian system, but results with different species (rats vs. hamsters) techniques (in vivo vitro; systemic intracerebral drug delivery) have been discordant. Here we examined effects 5-HT 1A/7 agonist 8-OH-DPAT 1/2 quipazine on system mice, some parallel experiments conducted hamsters for comparative purposes. In neither drug, delivered systemically at range phases doses,...