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Alertness
Kinds of Alertness Selected AbstractsDiurnal variations in the waking EEG: comparisons with sleep latencies and subjective alertnessJOURNAL OF SLEEP RESEARCH, Issue 3 2000Lafrance Daytime measures of sleep latency and subjective alertness do not correlate with one another, suggesting that they assess different aspects of alertness. In addition, their typical diurnal variations show very different time courses. Quantitative analysis of the waking electroencephalogram (EEG) has been proposed as an objective measure of alertness, but it is not clear how it compares with other measures. In this study, the waking EEG was measured in the daytime to determine the presence of diurnal variations in the activity of standard frequency bands and to compare these variations with the temporal patterns typical of sleep propensity and subjective alertness. Alertness was evaluated in four men and 12 women, aged 19,33 y. Assessments were conducted every 2 h, from 10.00 to 24.00, in the following order: a visual analogue scale of alertness, a waking EEG recording and a sleep latency test. The waking EEG was recorded with eyes open. For each recording session, 32,60 s of artefact-free signals were selected from the C3/A2 derivation, then subjected to amplitude spectral analysis. Four EEG frequency bands showed significant diurnal variations: delta, theta, sigma and beta1. None of these variations showed a significant correlation with the temporal patterns of sleep latencies or subjective alertness. At the individual level, however, theta band activity increased when subjective alertness decreased, suggesting that the theta band can be used to monitor variations in alertness in a given individual, even at the moderate levels of sleepiness experienced during the daytime. [source] Role of orexins in the hypothalamic-pituitary-ovarian relationshipsACTA PHYSIOLOGICA, Issue 3 2010P. Silveyra Abstract Appropriate nutritional and vigilance states are needed for reproduction. In previous works, we described the influence of the hormonal milieu of proestrus on the orexinergic system and we found that orexin receptor 1 expression in the hypothalamus, but not other neural areas, and the adenohypophysis was under the influence of oestradiol and the time of the day. Information from the sexual hormonal milieu of proestrous afternoon impacts on various components of the orexinergic system and alertness on this particular night of proestrus would be of importance for successful reproduction. In this review, we summarize the available experimental data supporting the participation of orexins in the hypothalamic-pituitary-ovarian relationships. All together, these results suggest a role of the orexinergic system as an integrative link among vital functions such as reproduction, food intake, alertness and the inner biological clock. [source] Vagus nerve stimulation for treatment of epilepsy in Rett syndromeDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 8 2006Angus A Wilfong MD, Assistant Professor This case series presents the outcomes of seven females with Rett syndrome and medically refractory epilepsy who were treated with adjunctive vagus nerve stimulation (VNS) therapy for a minimum of 12 months. Patients ranged in age from 1 to 14 years (median age 9y) at the time of implantation, had experienced seizures for a median period of approximately 6 years, and had failed at least two trials of antiepileptic drugs before receiving VNS. The median number of seizures per month was 150 (range 12,3600). At 12 months, six females had ,50% reduction in seizure frequency. VNS was safe and well tolerated, with no surgical complications and no patients requiring explantation of the device. Quality of life outcomes of note among these patients included reports at 12 months of increased alertness among all seven patients. No change in mood or communication abilities was noted. [source] Modulation of spatial attention in a child with developmental unilateral neglectDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 4 2003Veronika B Dobler MD Attentional neglect of left space is one of the most striking acquired neurological disorders of adulthood. Recent evidence indicates a link between left spatial neglect and general right-hemisphere impairments in sustained attention and alertness. Poor sustained attention and alertness is also a central feature of other disorders, particularly childhood attention-deficit-hyperactivity disorder (ADHD). Here we present the case of a 7-year-old male showing that frank neglect can be present in children with sustained attention problems without a clear aetiological event, or obvious structural brain abnormalities as indicated by a normal MRI. Experimental amelioration of the neglect through left-hand movement and externally alerting stimulation by uninformative sounds further suggest close similarities to the adult disorder. We suggest that such distortions of spatial attention may be more common in childhood than previously thought. [source] Fetal size in mid- and late pregnancy is related to infant alertness: The generation R studyDEVELOPMENTAL PSYCHOBIOLOGY, Issue 2 2009Jens Henrichs Abstract The vulnerability for behavioral problems is partly shaped in fetal life. Numerous studies have related indicators of intrauterine growth, for example, birth weight and body size, to behavioral development. We investigated whether fetal size in mid- and late pregnancy is related to infant irritability and alertness. In a population-based birth cohort of 4,255 singleton full-term infants ultrasound measurements of fetal head and abdominal circumference in mid- and late pregnancy were performed. Infant irritability and alertness scores were obtained by the Mother and Baby Scales at 3 months and z -standardized. Multiple linear regression analyses revealed curvilinear associations (inverted J-shape) of measures of fetal size in both mid- and late pregnancy with infant alertness. Fetal size characteristics were not associated with infant irritability. These results suggest that alterations of intrauterine growth affecting infant alertness are already detectable from mid-pregnancy onwards. © 2008 Wiley Periodicals, Inc. Dev Psychobiol 51: 119,130, 2009 [source] The Relative Influence of Epileptic EEG Discharges, Short Nonconvulsive Seizures, and Type of Epilepsy on Cognitive FunctionEPILEPSIA, Issue 1 2004Albert Aldenkamp Summary: Purpose: This study addressed whether cognitive impairment in children with epilepsy is caused by disease-related stable factors, such as the type of epilepsy, or by acute effects of paroxysmal epileptic activity such as epileptic EEG discharges. We studied a nonselected group with short nonconvulsive seizures, as these seizures may elude detection and may therefore persist over a longer period. In this group, the diagnostic issue is to differentiate between the combined effects of several epilepsy-related factors on cognition. Methods: All children were assessed with 32-channel EEG, synchronized with a computerized cognitive test system and a video-monitoring system. Recording time was 2 h. The primary inclusion criteria were unclear seizures and fluctuations in cognitive performance and/or frequent epileptic EEG discharges in a recent EEG. Results: One hundred fifty-two patients met the inclusion criteria; 31 patients appeared not to have a diagnosis of epilepsy and were used as a nonepilepsy control group. Our results show that type of epilepsy has an impact on stable cognitive functions, such as educational achievement. Paroxysmal epileptic activity (acute effects of seizures and epileptic EEG discharges) affects primarily transient mechanistic cognitive processes (alertness, mental speed). Conclusions: These results suggest that the effects of paroxysmal epileptic activity on transient cognitive mechanisms may accumulate over time and consequently affect the more stable aspects of cognitive function such as educational achievement. The clinical relevance is that early detection of the cognitive impact of seizure-related activity and subsequent treatment may prevent its detrimental impact on cognitive and educational development. [source] Topiramate in Patients with Learning Disability and Refractory EpilepsyEPILEPSIA, Issue 4 2002Kevin Kelly Summary: ,Purpose: Management of seizures in learning disabled people is challenging. This prospective study explored the efficacy and tolerability of adjunctive topiramate (TPM) in patients with learning disability and refractory epilepsy attending a single centre. Methods: Sixty-four patients (36 men, 28 women, aged 16,65 years) were begun on adjunctive TPM after a 3-month prospective baseline on unchanged medication. Efficacy end points were reached when a consistent response was achieved over a 6-month period at optimal TPM dosing. These were seizure freedom or ,50% seizure reduction (responder). Appetite, behaviour, alertness, and sleep were assessed by caregivers throughout the study. Results: Sixteen (25%) patients became seizure free with adjunctive TPM. There were 29 (45%) responders. A further 10 (16%) patients experiencing a more modest improvement in seizure control continued on treatment at the behest of their family and/or caregivers. TPM was discontinued in the remaining nine (14%) patients, mainly because of side effects. Final TPM doses and plasma concentrations varied widely among the efficacy outcome groups. Many patients responding well to adjunctive TPM did so on ,200 mg daily. Mean carer scores did not worsen with TPM therapy. Conclusions: TPM was effective as add-on therapy in learning-disabled people with difficult-to-control epilepsy. Seizure freedom is a realistic goal in this population. [source] Lamotrigine Therapy of Epilepsy in Tuberous SclerosisEPILEPSIA, Issue 7 2001David Neal Franz Summary: ,Purpose: Lamotrigine (LTG), a newer antiepileptic drug (AED), has activity against both partial-onset and generalized seizures. Its reported benefits for behavior, and its effectiveness in Lennox,Gastaut syndrome and other forms of refractory epilepsy, make it a logical choice for treatment of epilepsy in tuberous sclerosis complex (TSC). We present our experience with LTG therapy of epilepsy in 57 patients with TSC. Methods: Patients fulfilled the diagnostic criteria for clinically definite TSC. LTG was initiated and increased until improvement in seizure frequency was noted, intolerable side effects occurred, or maximal doses were reached. Seizure frequency and behavioral changes were recorded during LTG therapy and compared with those prior to the introduction of LTG. Results: Twenty-four (42%) were seizure free, and 21 (37%) had a >50% reduction in seizure frequency. Eighteen (32%) had subjectively improved behavior and/or alertness with daily activities. Thirty-eight (67%) had no change in this regard, whereas one (2%) became worse. Responders were more likely to not have a history of infantile spasms, and to have experienced only partial seizures (p < 0.05). Otherwise no phenotypic correlations with response were apparent. Conclusions: Among patients with TSC and epilepsy, LTG was effective and well tolerated, including as initial monotherapy. Improved alertness and behavior were apparent in many patients. The incidence of side effects is similar to that reported for other pediatric populations with symptomatic partial epilepsy. The usefulness of LTG in TSC may relate to an underlying defect of glutamatergic neurotransmission in partial epilepsy. [source] Effect of Exogenous Melatonin on Mood and Sleep Efficiency in Emergency Medicine Residents Working Night ShiftsACADEMIC EMERGENCY MEDICINE, Issue 8 2000Milan Jockovich MD Abstract. Objective: To determine whether melatonin taken prior to attempted daytime sleep sessions will improve daytime sleep quality, nighttime sleepiness, and mood state in emergency medicine (EM) residents, changing from daytime to nighttime work schedules. Methods: A prospective, randomized, double-blind crossover design was used in an urban emergency department. Emergency medicine residents who worked two strings of nights, of at least three nights' duration each, and separated by at least one week of days were eligible. Subjects were randomized to receive either melatonin 1 mg or placebo, 30 to 60 minutes prior to their daytime sleep session, for three consecutive days after each night shift. Crossover to the other agent occurred during their subsequent night shifts. Objective measures of quality of daytime sleep were obtained using the Actigraph 1000. This device measures sleep motion and correlates with sleep efficiency, total sleep time, time in bed, and sleep latency. The Profile of Mood States (POMS) and the Stanford Sleepiness Scale (SSS) were also used to quantify nighttime mood and sleepiness. Results: Among the 19 volunteers studied, there was no difference in sleep efficiency (91.16% vs 90.98%, NS), sleep duration (379.6 min vs 342.7 min, NS), or sleep latency (7.59 min vs 6.80 min, NS), between melatonin and placebo, respectively. In addition, neither the POMS total mood disturbance (5.769 baseline vs 12.212 melatonin vs 5.585 placebo, NS) nor the SSS (1.8846 baseline vs 2.2571 melatonin vs 2.1282 placebo, NS) demonstrated a statistical difference in nighttime mood and sleepiness between melatonin and placebo. Conclusions: There are no beneficial effects of a 1-mg melatonin dose on sleep quality, alertness, or mood state during night shift work among EM residents. [source] A Combination of Midazolam and Ketamine for Procedural Sedation and Analgesia in Adult Emergency Department PatientsACADEMIC EMERGENCY MEDICINE, Issue 3 2000Carl R. Chudnofsky MD Abstract Objective: To describe the clinical characteristics of a combination of midazolam and ketamine for procedural sedation and analgesia in adult emergency department (ED) patients. Methods: This was a prospective, observational trial, conducted in the ED of an urban level II trauma center. Patients , 18 years of age requiring procedural sedation and analgesia were eligible, and enrolled patients received 0.07 mg/kg of intravenous midazolam followed by 2 mg/kg of intravenous ketamine. Vital signs were recorded at regular intervals. The adequacy of sedation, adverse effects, patient satisfaction, and time to reach discharge alertness were determined. Descriptive statistics were calculated using statistical analysis software. Results: Seventy-seven patients were enrolled. Three were excluded due to protocol violations, three due to lack of documentation, and one due to subcutaneous infiltration of ketamine, leaving 70 patients for analysis. The average age was 31 years, and 41 (59%) were female. Indications for procedural sedation and analgesia included abscess incision and drainage (66%), fracture/joint reduction (26%), and other (8%). The mean dose of midazolam was 5.6 ± 1.4 mg and the mean dose of ketamine was 159 ± 42 mg. The mean time to achieve discharge criteria was 64 ± 24 minutes. Fivepatients experienced mild emergence reactions, but there were no episodes of hallucinations, delirium, or other serious emergence reactions. Eighteen (25%) patients recalled dreaming while sedated; twelve (17%) were described as pleasant, two (3%) unpleasant, three (4%) both pleasant and unpleasant, and one (1%) neither pleasant nor unpleasant. There were four (6%) cases of respiratory compromise, two (3%) episodes of emesis, and one (1%) case of myoclonia. All of these were transient and did not result in a change in the patient's disposition. Only one (1%) patient indicated that she was not satisfied with the sedation regimen. Conclusions: The combination of midazolam and ketamine provides effective procedural sedation and analgesia in adult ED patients, and appears to be safe. [source] Impact of the novel antidepressant agomelatine on disturbed sleep,wake cycles in depressed patients,HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 3 2010Maria-Antonia Quera-Salva Abstract Background Disturbance of sleep,wake cycles is common in major depressive disorder (MDD), usually as insomnia, but also as hypersomnia or reduced daytime alertness. Agomelatine, an MT1 and MT2 receptor agonist and 5-HT2C receptor antagonist, represents a novel approach in MDD, with proven antidepressant efficacy and a positive impact on the sleep,wake cycle. We review the effects of agomelatine 25/50,mg/day on objective and subjective measures of the sleep,wake cycle in MDD. Subjective measures Agomelatine improved all aspects of the sleep,wake cycle from as early as 1 week in randomized trials versus selective serotonin reuptake inhibitors and venlafaxine, particularly getting off to sleep and quality of sleep, with an improvement in daytime alertness. Objective measures Agomelatine's effect on sleep architecture in MDD has been measured by polysomnography (PSG). There were significant improvements in sleep efficiency, slow-wave sleep (SWS), and the distribution of delta activity throughout the night, but no change in amount or latency of rapid eye movement (REM) sleep. Furthermore, the slow-wave sleep was resynchronized to the first sleep cycle of the night. Conclusion Agomelatine, a novel antidepressant, improves disturbed sleep,wake cycles in MDD. The improvement of both nighttime sleep and daytime functioning with agomelatine are promising features of this antidepressant regarding the management of MDD. Copyright © 2010 John Wiley & Sons, Ltd. [source] Evaluation of the cognitive, psychomotor and pharmacokinetic profiles of rupatadine, hydroxyzine and cetirizine, in combination with alcohol, in healthy volunteersHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 1 2006Manuel J. Barbanoj Abstract Introduction The Central Nervous System (CNS) impairment induced by moderate alcohol (ALC) ingestion may be enhanced if other drugs are taken simultaneously. Rupatadine (RUP) is a new H1 -antihistamine which also inhibits platelet activating factor (PAF) release in inflammatory reactions. Objective The main aim of the study was to assess the effects of ALC 0.8,g/Kg on RUP (10,mg and 20,mg) CNS effects. An evaluation of alcohol and RUP pharmacokinetics was also attained. Methods Eighteen healthy young volunteers of both sexes participated in a phase I, randomised, crossover, double-blind, placebo-controlled study. At 2-week intervals they received six treatments: (a) placebo (PLA), (b) ALC alone and ALC in combination with: (c) hydroxyzine 25,mg (HYD), (d) cetirizine 10,mg (CET), (e) RUP 10,mg or (f) RUP 20,mg. At baseline and several times thereafter, seven psychomotor performance tests (finger tapping, fine motoric skills, nystagmus, temporal estimation, critical-flicker-fusion frequency, ,d2' cancellation, simple reaction) and eleven subjective self-reports (drunkenness, sleepiness, alertness, clumsiness, anger, inattentiveness, efficiency, happiness, hostility, interest and extraversion) were carried out. Two-way (treatment, time) ANOVAs for repeated measures to each variable together with a multivariate non-parametric approach were applied. Plasma concentrations of alcohol, and of RUP and its metabolites, were quantified by validated immunofluorescence and LC/MS/MS methods, respectively. Plasma-time curves for all compounds were analysed by means of model-independent methods. Results The combination of alcohol with HYD, CET and RUP 20,mg produced more cognitive and psychomotor impairment as compared to alcohol alone, being the combination of alcohol and HYD the one which induced the greatest deterioration. The combination of alcohol and RUP 10,mg could not be differentiated from ALC alone. Subjective self-reports reflect effects on metacognition after the combination of alcohol with HYD and CET i.e. the increased objective impairment observed was not subjectively perceived by the subjects. No significant differences were obtained when comparing alcohol plasma concentrations assessed after the treatments evaluated. RUP showed a lineal kinetic relationship after 10 and 20,mg with a higher exposition to both metabolites assayed. Conclusions Present results showed that single oral doses of rupatadine 10,mg in combination with alcohol do not produce more cognitive and psychomotor impairment than alcohol alone. Higher doses of rupatadine, in combination with alcohol, may induce cognitive and psychomotor deterioration as hydroxyzine and cetirizine at therapeutic doses. Copyright © 2006 John Wiley & Sons, Ltd. [source] Comparing effects of methylphenidate, sertraline and placebo on neuropsychiatric sequelae in patients with traumatic brain injuryHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 2 2005Hoon Lee Abstract Background This study aimed to investigate the effects of methylphenidate and sertraline compared with placebo on various neuropsychiatric sequelae associated with traumatic brain injury (TBI). Methods This was a 4 week, double-blind, parallel-group trial. Thirty patients with mild to moderate degrees of TBI were randomly allocated to one of three treatment groups (n,=,10 in each group) with matching age, gender and education, i.e. methylphenidate (starting at 5,mg/day and increasing to 20,mg/day in a week), sertraline (starting at 25,mg/day and increasing to 100,mg/day in a week) or placebo. At the baseline and at the 4 week endpoint, the following assessments were administered: subjective (Beck Depression Inventory) and objective (Hamilton Depression Rating Scale) measures of depression; Rivermead Postconcussion Symptoms Questionnaire for postconcussional symptoms; SmithKline Beecham Quality of Life Scale for quality of life; seven performance tests (Critical Flicker Fusion, Choice Reaction Time, Continuous Tracking, Mental Arithmetic, Short-Term memory, Digit Symbol Substitution and Mini-Mental State Examination); subjective measures of sleep (Leeds Sleep Evaluation Questionnaire) and daytime sleepiness (Epworth Sleepiness Scale). All adverse events during the study period were recorded and their relationships to the drugs were assessed. Results Neuropsychiatric sequelae seemed to take a natural recovery course in patients with traumatic brain injury. Methylphenidate had significant effects on depressive symptoms compared with the placebo, without hindering the natural recovery process of cognitive function. Although sertraline also had significant effects on depressive symptoms compared with the placebo, it did not improve many tests on cognitive performances. Daytime sleepiness was reduced by methylphenidate, while it was not by sertraline. Conclusions Methylphenidate and sertraline had similar effects on depressive symptoms. However, methylphenidate seemed to be more beneficial in improving cognitive function and maintaining daytime alertness. Methylphenidate also offered a better tolerability than sertraline. Copyright © 2005 John Wiley & Sons, Ltd. [source] Cross-cultural validation of the Leeds sleep evaluation questionnaire (LSEQ) in insomnia patientsHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 8 2003Ricardo Tarrasch Abstract The Leeds sleep evaluation questionnaire (LSEQ) is a standardized self-reporting instrument comprising ten 100,mm visual analogue scales that pertain to the ease of getting to sleep (GTS), quality of sleep (QOS), ease of awakening from sleep (AFS) and alertness and behaviour following wakefulness (BFW). Although the LSEQ has been used in a variety of populations, published psychometric data on insomnia patients are limited. The LSEQ reliability and construct validity was evaluated in 396 French insomnia patients aged 55 years and over, who were treated with placebo (2 weeks) and melatonin (3 weeks). The results supported LSEQ internal consistency, reliability and construct validity with minor differences from those of the original English version. Then the internal consistency of the LSEQ was evaluated in 257 insomnia patients (age 20,80 years) in France and Israel who, following a 1 week placebo baseline, were randomized to placebo or melatonin treatment for 3 weeks. Cronbach's , and Pearson's r correlation coefficients for placebo and drug treatment conditions (p<0.001 for all) supported LSEQ internal consistency in different treatment and age groups and in different languages. It is concluded that the consistency, reliability and validity of the four LSEQ domains allows them to be singled out as independent outcome variables in cross cultural sleep research and clinical practice in adult and elderly patients with insomnia. Copyright © 2003 John Wiley & Sons, Ltd. [source] The effects of caffeine on simulated driving, subjective alertness and sustained attentionHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 7 2001Carolyn Brice Abstract There is evidence that caffeine increases alertness and reduces fatigue. This may be especially so in low arousal situations (e.g. working at night or for prolonged hours). Caffeine has also been found to improve performance on vigilance tasks and simple tasks requiring sustained response. Again, these effects are often clearest when alertness is reduced, although there is evidence that benefits may still occur when the individual is unimpaired. Most studies to date have investigated the behavioural effects of caffeine in laboratory experiments using artificial tasks. In the current study 3,mg/kg caffeine was found to improve steering accuracy in a 1,h simulated drive. Measures of mood and performance on a sustained attention task also showed the benefits of caffeine. These findings suggest that laboratory results reflect a general benefit of caffeine that may also be observed in real-life situations. Other evidence examining the effects of caffeine on performance efficiency over the working day has shown the benefits of caffeine consumption on measures of sustained attention and alertness. This study also provided evidence suggesting that caffeine is often consumed when alertness is low to maximise alertness and performance efficiency. The implications of these findings for road safety are also considered. Copyright © 2001 John Wiley & Sons, Ltd. [source] Human resources planning on terrorism and crises in the Asia Pacific region: Cross-national challenge, reconsideration, and proposition from western experiencesHUMAN RESOURCE MANAGEMENT, Issue 1 2008Dian-Yan Liou Since the 9/11 attacks in the United States (2001) and the two bombing events in Bali (2002, 2005), there has been renewed interest in emergency prevention policies in many organizations around the world. Functional terrorism preparedness requires changes in organizational thinking about external environmental threats. This shift in organizational thinking could be led by human resource departments. In order to achieve this goal, HR departments must redefine their role in terms of crisis management, and then four key planning measures for insuring postemergency operations should be observed. Using system dynamics (SD) methodology, this article examines the causes of states in which organizations operate after terrorist attacks. Based on the qualitative analytic approach of causal loops, this article explores the major challenges for HR development prompted by terrorism. Specifically, we focus on changes both to organizational communication and to workforce planning and succession. These activities are a tremendous challenge immediately following a disaster. A functional HR plan must include elements for proactive alertness, the ability to dispatch inventory, evacuation plans, and record preservation coupled with dissemination to employees and explicit employee training and cross-cultural management. © 2008 Wiley Periodicals, Inc. [source] Time budgets of Snow Geese Chen caerulescens and Ross's Geese Chen rossii in mixed flocks: implications of body size, ambient temperature and family associationsIBIS, Issue 1 2009JÓN EINAR JÓNSSON Body size affects foraging and forage intake rates directly via energetic processes and indirectly through interactions with social status and social behaviour. Ambient temperature has a relatively greater effect on the energetics of smaller species, which also generally are more vulnerable to predator attacks than are larger species. We examined variability in an index of intake rates and an index of alertness in Lesser Snow Geese Chen caerulescens caerulescens and Ross's Geese Chen rossii wintering in southwest Louisiana. Specifically we examined variation in these response variables that could be attributed to species, age, family size and ambient temperature. We hypothesized that the smaller Ross's Geese would spend relatively more time feeding, exhibit relatively higher peck rates, spend more time alert or raise their heads up from feeding more frequently, and would respond to declining temperatures by increasing their proportion of time spent feeding. As predicted, we found that Ross's Geese spent more time feeding than did Snow Geese and had slightly higher peck rates than Snow Geese in one of two winters. Ross's Geese spent more time alert than did Snow Geese in one winter, but alert rates differed by family size, independent of species, in contrast to our prediction. In one winter, time spent foraging and walking was inversely related to average daily temperature, but both varied independently of species. Effects of age and family size on time budgets were generally independent of species and in accordance with previous studies. We conclude that body size is a key variable influencing time spent feeding in Ross's Geese, which may require a high time spent feeding at the expense of other activities. [source] Relationships between tail-flicking, morphology, and body condition in MoorhensJOURNAL OF FIELD ORNITHOLOGY, Issue 1 2006Fernando Alvarez ABSTRACT Prey-predator communication of alertness has been reported for Moorhens (Gallinula chloropus) and other species of birds. Because ability to flee is probably related to body condition, healthy potential prey may behave more conspicuously to send predators an unambiguous message. Moorhens have a contrasting rump patch that is flashed by rapid tail-flicking. During two winter months, we observed sex-related differences in the rate of tail-flicking. Females tail-flicked at a faster rate than males, and more vigilant and more symmetrical males tail-flicked faster. The rate of tail-flicking was negatively correlated to the heterophil/lymphocyte ratio in both sexes and positively correlated to hematocrit and albumin/globulin ratio in females. These results suggest that male and female Moorhens in better physical condition tail-flick at a faster rate and support the pursuit deterrent hypothesis, with healthy individuals appearing to inform predators that they would be difficult to capture. SINOPSIS Es conocida la comunicación del estado de alerta de las presas hacia los predadores potenciales en la Gallineta Gallinula chloropus y en otras especies de aves. Puesto que la facilidad de captura está probablemente relacionada con la condición física, sería de esperar que los individuos presa en mejor condición física actuaran de forma más conspicua, pudiendo así informar sin ambigüedad a los predadores. La Gallineta presenta un escudo anal contrastado, que se hace más conspicuo mediante rápidos movimientos verticales de la cola. Durante dos meses invernales se registraron las diferencias en la tasa de movimiento de cola con relación al sexo de los sujetos, así como su relación con la tasa de vigilancia y con varios parámetros de condición física. Las hembras presentaron mayor tasa de exhibición del escudo anal que los machos, y los más vigilantes y más simétricos de éstos realizaron una exhibición más rápida. Mientras que en ambos sexos la tasa de exhibición apareció relacionada negativamente con la razón heterófilos/linfocitos, en las hembras se mostró positivamente relacionada con su hematocrito y con la razón albúmina/globulina. Estos resultados sugieren que los machos y hembras con mejor salud, así como los machos con tarsos más simétricos, realizan una más rápida exhibición, lo que apoya la hipótesis del efecto disuasorio a la persecución, ya que las presas potenciales podrían estar informando a los predadores respecto a la dificultad de su captura. [source] Intake of Energy Drinks in Association With Alcoholic Beverages in a Cohort of Students of the School of Medicine of the University of MessinaALCOHOLISM, Issue 10 2007Alessandro Oteri Background:, Energy drinks (ED) are a widely used group of beverages known for their stimulant effects on central nervous system (CNS). The main components of ED are caffeine, taurine, carbohydrates, glucuronolactone, inositol, niacin, pantenol, and , -complex vitamins. The studies evaluating the effects of ED describe improvements in attention and/or reaction times and indices of alertness. It has been also shown that combination of caffeine and glucose, fundamental constituents of ED, can ameliorate deficits in cognitive performance and subjective fatigue during extended periods of cognitive demand. Moreover, the associated ingestion of alcohol and ED has recently been observed to be becoming more and more widespread. Methods:, With the aim to know the habits and uses of students, we administered a questionnaire containing questions regarding ED drinking alone or in association with alcoholic beverages. Five hundred students of the School of Medicine of the University of Messina were interviewed, and 450 filled the questionnaire. Results:, A total of 56.9% of students declared using ED. A great part of users (48.4%) associate frequently ED and alcohol. In particular, 35.8% of ED + alcohol users have used ED + alcohol more than 3 times in the last month. Distinguishing the users into 2 groups (users of ED + alcohol and users of both ED and ED + alcohol), we observed in the second group a major use of cocktail containing a mix of ED and alcoholic beverages. This difference between the 2 groups is less represented about the ingestion of ED + alcohol in the night. Conclusions:, Our data indicate that association of ED + alcohol is very popular among students. This behavior can be dangerous. In fact, the combination of ED + alcoholic drinks can reduce adversive symptoms of alcohol intoxication including the depressant effects. As consequence, users of ED + alcoholic beverages might not feel the signs of alcohol intoxication, thus increasing the probability of accidents and/or favoring the possibility of development of alcohol dependence. [source] Investigating the interaction between the homeostatic and circadian processes of sleep,wake regulation for the prediction of waking neurobehavioural performanceJOURNAL OF SLEEP RESEARCH, Issue 3 2003Hans P. A. Van Dongen Summary The two-process model of sleep regulation has been applied successfully to describe, predict, and understand sleep,wake regulation in a variety of experimental protocols such as sleep deprivation and forced desynchrony. A non-linear interaction between the homeostatic and circadian processes was reported when the model was applied to describe alertness and performance data obtained during forced desynchrony. This non-linear interaction could also be due to intrinsic non-linearity in the metrics used to measure alertness and performance, however. Distinguishing these possibilities would be of theoretical interest, but could also have important implications for the design and interpretation of experiments placing sleep at different circadian phases or varying the duration of sleep and/or wakefulness. Although to date no resolution to this controversy has been found, here we show that the issue can be addressed with existing data sets. The interaction between the homeostatic and circadian processes of sleep,wake regulation was investigated using neurobehavioural performance data from a laboratory experiment involving total sleep deprivation. The results provided evidence of an actual non-linear interaction between the homeostatic and circadian processes of sleep,wake regulation for the prediction of waking neurobehavioural performance. [source] Daytime sleepiness during Ramadan intermittent fasting: polysomnographic and quantitative waking EEG studyJOURNAL OF SLEEP RESEARCH, Issue 2 2003Rachida Roky Summary During the lunar month of Ramadan, Muslims abstain from eating, drinking and smoking from sunrise to sunset. We reported previously that Ramadan provokes a shortening in nocturnal total sleep time by 40 min, an increase in sleep latency, and a decrease in slow-wave sleep (SWS) and rapid eye movement (REM) sleep duration during Ramadan. During the same study, the effects of Ramadan intermittent fasting on daytime sleepiness were also investigated in eight healthy young male subjects using a quantitative waking electroencephalograph (EEG) analysis following the multiple sleep latency test (MSLT) procedure. This procedure was combined with subjective alertness and mood ratings and was conducted during four successive experimental sessions: (1) baseline (BL) 15 days before Ramadan, (2) beginning of Ramadan (R11) on the 11th day of Ramadan, (3) end of Ramadan (R25) on the 25th day of Ramadan, (4) recovery 2 weeks after Ramadan (AR). During each session, four 20-min nap opportunities (MSLTs) were given at 10:00, 12:00, 14:00 and 16:00 h and were preceded by rectal temperature readings. Nocturnal sleep was recorded before each daytime session. Subjective daytime alertness did not change in R25 but decreased in R11 at 12:00 h, and subjective mood decreased at 16:00 h, both in R11 and R25. During the MSLT, mean sleep latency decreased by an average of 2 min in R11 (especially at 10:00 and 16:00 h) and 6 min in R25 (especially at 10:00 and 12:00 h) compared with BL. There was an increase in the daily mean of waking EEG absolute power in the theta (5.5,8.5 Hz) frequency band. Significant correlations were found between sleep latency during the MSLT and the waking EEG absolute power of the fast alpha (10.5,12.5 Hz), sigma (11.5,15.5 Hz) and beta (12.5,30 Hz) frequency bands. Sleep latency was also related to rectal temperature. In conclusion, Ramadan diurnal fasting induced an increase in subjective and objective daytime sleepiness associated with changes in diurnal rectal temperature. [source] Diurnal variations in the waking EEG: comparisons with sleep latencies and subjective alertnessJOURNAL OF SLEEP RESEARCH, Issue 3 2000Lafrance Daytime measures of sleep latency and subjective alertness do not correlate with one another, suggesting that they assess different aspects of alertness. In addition, their typical diurnal variations show very different time courses. Quantitative analysis of the waking electroencephalogram (EEG) has been proposed as an objective measure of alertness, but it is not clear how it compares with other measures. In this study, the waking EEG was measured in the daytime to determine the presence of diurnal variations in the activity of standard frequency bands and to compare these variations with the temporal patterns typical of sleep propensity and subjective alertness. Alertness was evaluated in four men and 12 women, aged 19,33 y. Assessments were conducted every 2 h, from 10.00 to 24.00, in the following order: a visual analogue scale of alertness, a waking EEG recording and a sleep latency test. The waking EEG was recorded with eyes open. For each recording session, 32,60 s of artefact-free signals were selected from the C3/A2 derivation, then subjected to amplitude spectral analysis. Four EEG frequency bands showed significant diurnal variations: delta, theta, sigma and beta1. None of these variations showed a significant correlation with the temporal patterns of sleep latencies or subjective alertness. At the individual level, however, theta band activity increased when subjective alertness decreased, suggesting that the theta band can be used to monitor variations in alertness in a given individual, even at the moderate levels of sleepiness experienced during the daytime. [source] Rhythms of Mental PerformanceMIND, BRAIN, AND EDUCATION, Issue 1 2008Pablo Valdez ABSTRACT, Cognitive performance is affected by an individual's characteristics and the environment, as well as by the nature of the task and the amount of practice at it. Mental performance tests range in complexity and include subjective estimates of mood, simple objective tests (reaction time), and measures of complex performance that require decisions to be made and priorities set. Mental performance tasks show 2 components, a circadian rhythm and the effects of time awake. The circadian rhythm is in phase with the rhythm of core temperature and there is evidence for a causal link. Increasing time awake results in performance deterioration and is attributed to fatigue. The relative contribution of these 2 components depends upon the task under consideration; simple tasks generally show smaller effects due to increasing time awake. These contributions have been assessed by constant routines and forced desynchronization protocols and have formed the basis of several mathematical models that attempt to predict performance in a variety of field conditions. Mental performance is negatively affected by sleep loss; although short naps are beneficial, sleep inertia limits their value immediately after waking. The processes involved in cognition include attention (tonic and phasic alertness, and selective and sustained attention), working memory (phonological, used for speech, reading, and writing; and visuospatial, used for spatial processing, drawing, and mathematics), and executive function (initiative, decision making, and problem solving). These processes are illuminated by analysis of the regions of the brain involved, the presence of circadian rhythmicity, and the effects of sleep loss. The results from such laboratory- and field-based observations are relevant to the issue of learning in schoolchildren and lead to suggestions for improving their performance. [source] Latest news and product developmentsPRESCRIBER, Issue 23-24 2007Article first published online: 8 JAN 200 Cervical cancer risk falls after COC use ends Combined oral contraceptives (COCs) are associated with a slight increase in the risk of cervical cancer but this diminishes with time after use ends, an international study has shown (Lancet 2007;370:1609,21). Analysis of data for 16 573 women with and 35 509 women without cervical cancer confirmed that using a COC for 10 years between the ages of 20 and 30 increases the incidence of invasive cervical cancer from 3.8 to 4.5 per 1000 by age 50. However, the excess risk disappears 10 years after cessation of use. , A new analysis of the US Nurses' Health Study suggests that protection against ovarian cancer does not persist beyond 20 years after cessation of COC use. This study also showed that tubal ligation is associated with reduced risk of ovarian cancer (Am J Epidemiol 2007; 166;894,901). Pharmaceutical services fund moves to PCTs The ,global sum' that provides central funding for NHS pharmaceutical services is being shifted to PCTs. The Government has included legislation for the change in the recent Health and Social Care Bill. The fund pays the fees and allowances for pharmacy contractors and appliance contractors. The Government says this is a ,natural progression and in keeping with moves to devolve NHS funds to the frontline' that will enable PCTs to manage pharmacy services better by ,encouraging best prescribing practice'. Fewer fluoroquinolones in the community Restricting prescribing of fluoroquinolone antibacterials does not increase hospital admissions for infection among older people, say Canadian researchers (Am J Med 2007;120:893,900). Their analysis of an Ontario medical database shows that, in a community where fluoroquinolones were the most widely prescribed antibacterials, a one-third reduction in prescribing was not followed by an increase in hospital admissions for infectious episodes in the over,65s. On the contrary, there was a 32 per cent reduction in admissions for gastrointestinal conditions. FDA reports increased TB risk with infliximab The US Food and Drug Administration has published an analysis of cases of TB associated with infliximab (Remicade) detected via its spontaneous adverse event reporting scheme (Ann Intern Med 2007;147: 699,702). In 2001 the FDA placed a warning about the risk of TB on product labelling for infliximab and advised testing for TB before initiating treatment. This analysis of 130 cases of TB since reported in patients treated with infliximab found that 45 per cent had developed extra-pulmonary disease; risk factors included use of immunosuppressants (including methotrexate), a history of TB and time spent in an endemic area. Of 67 cases in which treatment was initiated after the warning was issued, 34 with a negative tuberculin skin test developed TB after receiving infliximab. MHRA announces anticounterfeit strategy The UK is a transit point, distribution hub and end-user of counterfeit medicines, says the MHRA in its first anti-counterfeiting strategy (www.mhra.gov.uk). Counterfeits have been detected in the legitimate supply chain with increasing frequency since 2004, resulting in nine batch recalls and a further five incidents detected at wholesale level. The MHRA's proposed approach includes: communication to raise awareness of the risk and facilitate reporting, collaboration with the WHO, the industry and law enforcement agencies, and targeted surveillance, prosecution and regulation. Evidence lacking for choosing DMARD There is insufficient evidence to choose one DMARD or biological agent over another in patients with RA, US investigators say (www.annals.org/cgi/content/abstract/0000605,20080115000192v1). Their systematic review of meta-analyses and intervention and observational trials found no evidence of differences among DMARDs or anti-TNF agents. Mono-therapy with an anti-TNF agent was associated with superior radiographic but not clinical outcomes; methotrexate plus an anti-TNF agent was superior in clinical and functional terms to either drug given alone. Be alert to psychiatric ADRs with rimonabant Clinicians should remain alert for the development of anxiety, depression and an increased risk of suicide with rimonabant (Acomplia), say Danish investigators (Lancet 2007;370:1706,13). Their meta-analysis of four randomised trials involving a total of 4105 patients showed that rimonabant was associated with an increased risk of serious adverse events (odds ratio 1.4; number needed to harm, NNH, 59), including a 2.5,fold increased risk of depression (NNH 49) and a threefold increased risk of anxiety (NNH 166). Following a warning from the FDA of an increased risk of suicide with rimonabant, the authors say their findings indicate a need for ,increased alertness by physicians to these potentially severe psychiatric adverse reactions'. New strategy for NHS medicines information The UK Medicines Information Service (www.ukmi.nhs.uk) has published its new management strategy setting out how it will respond to recent developments in the NHS. Developments include greater access to information for patients, support for nontraditional prescribers and new commissioning arrangements. New antiretroviral Maraviroc (Celsentri) is the first CCR5 antagonist to be introduced for the treatment of HIV infection. CCR5 is one of two co-receptors to which the HIV virus must attach to achieve cell entry. Maraviroc is licensed for use by treatment-experienced patients in whom only CCR5-tropic HIV-1 is detectable. The recommended dose ranges from 150 to 600mg twice daily depending on interactions with concurrent medication. Dimeticone superior Dimeticone 4 per cent lotion (Hedrin) is superior to malathion 0.5 per cent in the eradication of head lice, a UK study in 58 children and 15 adults has shown (PLoS ONE 2007;2: e1127. doi:10.1371/journal.pone. 0001127). Two applications of dimeticone lotion one week apart cleared active infestation in 70 per cent of participants compared with 33 per cent in those who used a single application of malathion. Copyright © 2007 Wiley Interface Ltd. [source] Acute changes in carbon dioxide levels alter the electroencephalogram without affecting cognitive functionPSYCHOPHYSIOLOGY, Issue 4 2000Elisabeth Bloch-Salisbury The partial pressure of carbon dioxide in the arterial blood (PaCO2) is usually tightly regulated, yet it varies among healthy people at rest (range ,32,44 mmHg) as well as within an individual during many natural life situations. The present study examined whether modest changes in end-tidal PCO2 (PetCO2; a noninvasive measure of PaCO2) affect electroencephalographic (EEG) activity, cognitive function, and vigilance. Nine adults were ventilated mechanically using a mouthpiece; respiratory rate and breath size were held constant while PetCO2 was set to levels that produced minimal discomfort. Despite discrete changes in EEG, neither acute PetCO2 increases (mean = 47 mmHg) nor decreases (mean = 30 mmHg) from resting levels (mean = 38 mmHg) affected performance on cognitive tasks, latency or amplitude of the N1, P2, or P3 event-related potential, or alertness. Modest changes in PetCO2 may cause significant alterations in the EEG without disturbing cognitive function. [source] Positional Therapy for Obstructive Sleep Apnea Patients: A 6-Month Follow-Up StudyTHE LARYNGOSCOPE, Issue 11 2006Arie Oksenberg PhD Abstract Background: Approximately half of obstructive sleep apnea (OSA) patients are positional (i.e., the majority of their breathing abnormalities during sleep appear in the supine posture). Little information exists as to whether avoiding the supine posture during sleep (positional therapy) is a valuable form of therapy for these patients. Aim: To assess the use of positional therapy (by the tennis ball technique [TBT]) during a 6 month period in 78 consecutive positional OSA patients. Methods: Demographic, polysomnographic, and self-reported questionnaire data on the use of the TBT were analyzed. Results: Of the 50 patients who returned the questionnaire, 19 (38%) (group A) said they were still using the TBT, and 12 (24%) (group B) said they used it initially and stopped using it within a few months but were still avoiding the supine position during sleep. Nineteen patients (38%) (group C) stopped using the TBT within a few months but did not learn how to avoid the sleep supine posture. Patients still using the TBT showed a significant improvement in their self-reported sleep quality (P < .005) and daytime alertness (P < .046) and a decrease in snoring loudness (P < .001). Patients of groups A and B were older than patients who did not comply with this therapy (P < .001). The main reason for patients stopping the use of the TBT in group C was that using it was uncomfortable. Conclusions: Positional therapy appears to be a valuable form of therapy mainly for some older aged positional OSA patients. [source] Sleep induced by stimulation in the human pedunculopontine nucleus areaANNALS OF NEUROLOGY, Issue 4 2010Isabelle Arnulf MD The pedunculopontine nucleus is part of the reticular ascending arousal system and is involved in locomotion and sleep. Two patients with Parkinson disease received electrodes that stimulated the pedunculopontine nucleus area to alleviate their severe gait impairment. Instead, we found that low-frequency stimulation of the pedunculopontine nucleus area increased alertness, whereas high-frequency stimulation induced non-rapid eye movement sleep. In addition, the sudden withdrawal of the low-frequency stimulation was consistently followed by rapid eye movement sleep episodes in 1 patient. These data have the potential to benefit patients who suffer from sleep disorders. ANN NEUROL 2010;67:546,549 [source] GSM base stations: Short-term effects on well-being,BIOELECTROMAGNETICS, Issue 1 2009Christoph Augner Abstract The purpose of this study was to examine the effects of short-term GSM (Global System for Mobile Communications) cellular phone base station RF-EMF (radiofrequency electromagnetic fields) exposure on psychological symptoms (good mood, alertness, calmness) as measured by a standardized well-being questionnaire. Fifty-seven participants were selected and randomly assigned to one of three different exposure scenarios. Each of those scenarios subjected participants to five 50-min exposure sessions, with only the first four relevant for the study of psychological symptoms. Three exposure levels were created by shielding devices in a field laboratory, which could be installed or removed during the breaks between sessions such that double-blinded conditions prevailed. The overall median power flux densities were 5.2 µW/m2 during "low," 153.6 µW/m2 during "medium," and 2126.8 µW/m2 during "high" exposure sessions. For scenario HM and MH, the first and third sessions were "low" exposure. The second session was "high" and the fourth was "medium" in scenario HM; and vice versa for scenario MH. Scenario LL had four successive "low" exposure sessions constituting the reference condition. Participants in scenarios HM and MH (high and medium exposure) were significantly calmer during those sessions than participants in scenario LL (low exposure throughout) (P,=,0.042). However, no significant differences between exposure scenarios in the "good mood" or "alertness" factors were obtained. We conclude that short-term exposure to GSM base station signals may have an impact on well-being by reducing psychological arousal. Bioelectromagnetics 30:73,80, 2009. © 2008 Wiley-Liss, Inc. [source] Quantification of acetylcholine, an essential neurotransmitter, in brain microdialysis samples by liquid chromatography mass spectrometryBIOMEDICAL CHROMATOGRAPHY, Issue 1 2010Ramakrishna Nirogi Abstract Chemical neurotransmission has been the subject of intensive investigations in recent years. Acetylcholine is an essential neurotransmitter in the central nervous system as it has an effect on alertness, memory and learning. Enzymatic hydrolysis of acetylcholine in the synaptic cleft is fast and quickly metabolizes to choline and acetate by acetylcholinesterase. Hence the concentration in the extracellular fluid of the brain is low (0.1,6,nm). Techniques such as microdialysis are routinely employed to measure acetylcholine levels in living brain systems and the microdialysis sample volumes are usually less than 50,µL. In order to develop medicine for the diseases associated with cognitive dysfunction like mild cognitive impairment, Alzheimer's disease, schizophrenia and Parkinson's disease, or to study the mechanism of the illness, it is important to measure the concentration of acetylcholine in the extracellular fluid of the brain. Recently considerable attention has been focused on the development of chromatographic,mass spectrometric techniques to provide more sensitive and accurate quantification of acetylcholine collected from in-vivo brain microdialysis experiments. This review will provide a brief overview of acetylcholine biosynthesis, microdialysis technique and liquid chromatography mass spectrometry, which is being used to quantitate extracellular levels of acetylcholine. Copyright © 2009 John Wiley & Sons, Ltd. [source] Oxytocin as a "High Alert Medication": A Multilayered Challenge to the Status QuoBIRTH, Issue 4 2009Judith P. Rooks CNM ABSTRACT: Oxytocin is the drug most commonly associated with preventable adverse perinatal outcomes. In 2007 it was added to the Institute for Safe Medication Practices short list of medications "bearing a heightened risk of harm," which may "require special safeguards to reduce the risk of error." In January 2009 the American Journal of Obstetrics and Gynecology published a Clinical Opinion paper about oxytocin's inclusion on the list and how the obstetrics profession in the United States should respond. The authors call for the development of specific evidence-based guidelines to reduce the likelihood of patient harm by limiting elective use of oxytocin, decreasing the need for indicated use, reducing dosages during necessary use, giving more responsibility and authority for the patient's safety to the professional who is "at the bedside administering and monitoring the oxytocin infusion" (i.e., the nurse), and accepting that "more time rather than more oxytocin is generally preferable" once adequate uterine activity has been achieved. It is unfortunate that this important paper discounted the risk of harm from cesarean sections and did not mention the strong linkage between epidural analgesia and use of oxytocin. Physicians, midwives, nurses, and others should examine and discuss these issues further in view of increased alertness to the risk of harm from unsafe use of oxytocin. [source] | ||||||||||||||||||||||