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Introduction: The efficacy of bright light and/or melatonin treatment for Delayed Sleep Wake Phase Disorder (DSWPD) is contingent upon an accurate clinical assessment of the circadian phase. However, the process of determining this circadian phase can be costly and is not yet readily available in the clinical setting. The present study investigated whether more cost-effective and convenient estimates of the circadian phase, such as self-reported sleep timing, can be used to predict the circadian phase and guide the timing of light and/or melatonin treatment (i.e. dim-light melatonin onset, core body temperature minimum and melatonin secretion mid-point) in a sample of individuals with DSWPD., Method: Twenty-four individuals (male = 17; mean age = 21.96, SD = 5.11) with DSWPD were selected on the basis of ICSD-3 criteria from a community-based sample. The first 24-hours of a longer 80-hour constant laboratory ultradian routine were used to determine core body temperature minimum (cBT min ), dim-light melatonin onset (DLMO) and the midpoint of the melatonin secretion period (DLM mid = [DLM° ff -DLMO]/2). Prior to the laboratory session subjective sleep timing was assessed using a 7-day sleep/wake diary, the Pittsburgh Sleep Quality Index (PSQI), and the Delayed Sleep Phase Disorder Sleep Timing Questionnaire (DSPD-STQ)., Results: Significant moderate to strong positive correlations were observed between self-reported sleep timing variables and DLMO, cBT min and DLM mid . Regression equations revealed that the circadian phase (DLMO, cBT min and DLM mid ) was estimated within ±1.5 hours of the measured circadian phase most accurately by the combination of sleep timing measures (88% of the sample) followed by sleep diary reported midsleep (83% of the sample) and sleep onset time (79% of the sample)., Discussion: These findings suggest that self-reported sleep timing may be useful clinically to predict a therapeutically relevant circadian phase in DSWPD.

A significant delay in the timing of endogenous circadian rhythms has been associated with delayed sleep phase disorder (DSPD). More recently, other mechanisms have also been proposed to account for this disorder. To further explore the etiology of DSPD, the present study compared nocturnal melatonin profiles of 26 DSPD patients (18 males, 8 females; age, 21.73 ± 4.98 years) and 17 normally timed good sleepers (10 males, 7 females; age, 23.82 ± 5.23 years) in a time-free, dim-light (<10 lux) laboratory environment. A 30-h modified constant routine with alternating 20-min sleep opportunities and 40 min of enforced wakefulness was used to measure the endogenous melatonin circadian rhythm. Salivary melatonin was sampled half-hourly from 1820 h to 0020 h and then hourly from 0120 h to 1620 h. DSPD patients had significantly later timed melatonin profiles that were delayed by approximately 3 h compared to normal sleepers, and there were no notable differences in the relative duration of secretion between groups. However, melatonin secretion between dim-light melatonin onset (DLMO) and acrophase was less prominent in DSPD patients compared to good sleepers, who showed a more acute initial surge of melatonin following the DLMO. Although the regulatory role of melatonin is unknown, abnormal melatonin profiles have been linked to psychiatric and neurological disorders (e.g., major depression, obsessive compulsive disorder, Parkinson disease). These results therefore suggest that in addition to a delayed endogenous circadian rhythm, a diminished initial surge of melatonin secretion following DLMO may contribute to the etiology of DSPD., (© 2015 The Author(s).)

Cognitive processes play an important role in the maintenance, and treatment of sleep difficulties, including insomnia. In 2002, a comprehensive model was proposed by Harvey. Since its inception the model has received >300 citations, and provided researchers and clinicians with a framework for understanding and treating insomnia. The aim of this review is two-fold. First, we review the current literature investigating each factor proposed in Harvey's cognitive model of insomnia. Second, we summarise the psychometric properties of key measures used to assess the model's factors and mechanisms. From these aims, we demonstrate both strengths and limitations of the current knowledge of appropriate measurements associated with the model. This review aims to stimulate and guide future research in this area; and provide an understanding of the resources available to measure, target, and resolve cognitive factors that may maintain chronic insomnia., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Sleep problems are not a core feature of obsessive-compulsive disorder (OCD), but emerging empirical data indicate some form of sleep disruption to be highly common. Available research in both adult and child patients is limited in several important ways, including the use of subjective reports (particularly in children), high rates of comorbid depression, and concurrent use of psychotropic medication. The presence of sleep disruption in OCD patients may compound severity and impairment of the disorder. More research is needed to fully understand the nature and consequences of sleep-wake disruption in children with OCD., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Teenagers need sufficient sleep to function well daily, yet consolidated evidence advising which factors protect, or harm, adolescents' sleep is lacking. Forty-one studies, published between 2003 and February, 2014, were meta-analysed. Mean weighted r values were calculated to better understand the strength of protective and risk factors for 85,561 adolescents' (age range = 12-18 y) bedtime, sleep onset latency (SOL) and total sleep time (TST). Results showed good sleep hygiene and physical activity were associated with earlier bedtimes. Video gaming, phone, computer and internet use, and evening light related to delayed bedtimes. Good sleep hygiene negatively correlated with sleep latency. Alternatively, sleep latency lengthened as a negative family environment increased. Tobacco, computer use, evening light, a negative family environment and caffeine were associated with decreased total sleep, whereas good sleep hygiene and parent-set bedtimes related to longer sleep length. Good sleep hygiene appears to be protective, whereas a negative home environment and evening light appear to be risk factors. Cautious use of technology (other than television), caffeine, tobacco and alcohol should be considered. These factors, along with pre-sleep worry, are likely to have some negative impact on sleep. Parent-set bedtimes and physical activity may be beneficial. Future research directions are discussed., (Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.)

Aim: Technology use by adolescents close to bedtime commonly leads to sleep problems, and individual factors predicting those at heightened risk are under studied. We investigated whether risk-taking perceptions influenced length of adolescent technology use at bedtime and whether being aware of time moderated this association., Methods: We recruited 16 males and five females, with a mean age of 17.6 years, from school and university populations to assess adolescent technology use and bedtimes. They were assessed for trait risk-taking using the Cognitive Appraisal of Risky Events questionnaire and had unrestrained access to a video game on two separate nights, counterbalanced for clock present or clock absent conditions. The adolescents' self-selected bedtime provided a measure of the level of technology use and was the dependent variable., Results: Adolescents who perceived fewer negative consequences of risky activities on the Cognitive Appraisal of Risky Events played the video game longer and went to bed later than those who perceived more negative consequences (p = 0.03). There was no influence on bedtimes from perceived benefits of risk-taking or clock presence., Conclusion: Adolescents who perceived fewer negative consequences of risk-taking were more likely to stay up later using technology, facing a heightened risk of displaced sleep., (©2015 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.)

Adolescents' video gaming is increasing at a rapid rate. Yet, little is known about what factors contribute toward more hours of gaming per week, as well as what factors may limit or protect adolescents from excessive gaming. The aim of the present study was to examine associations between adolescents' accessibility to video gaming devices, the locations played (i.e., bedroom, shared rooms), parental regulation of technology use, and the amount of hours spent video gaming during the week (weekdays vs. weekends). Adolescents (N=422; age 16.3±2.0 years, 41% male) completed an online questionnaire battery, including demographics, video gaming behaviors (e.g., hours played weekdays/weekends, time of day played, devices owned, locations played, etc.), and a questionnaire measuring aspects of parents' regulation of game playing (e.g., rules, limit setting, co-gaming). Accessibility to the adolescents' own devices, but not shared devices or device portability, was predictive of hours gaming on weekdays and weekends. Location (i.e., bedroom) was associated with increased gaming across the week. Parents discussing cybersafety was predictive of lower hours of gaming (weekdays and weekends). However, limit setting, monitoring, and co-gaming showed no significant effects. Adolescents' access to their own gaming equipped devices, as well as gaming in their bedrooms, were linked to increased hours of gaming. The findings suggest that in order to curb the increase in hours gaming, parents are advised to delay the ownership of adolescents' devices, encourage use in shared rooms, and discuss aspects of cybersafety with their teenage children.

Objectives: The current study aimed to evaluate school-based motivational sleep education programs (SEPs) with adjunct bright light therapy (BLT) and/or parental involvement (PI)., Design: Randomized controlled trial., Setting: Six high schools, matched on socio-economic status (SES)., Participants: A total of 193 adolescents (mean age, 16.3 ± 0.4 years, 79%f)., Intervention: Classes were randomly assigned to (i) SEP + BLT, (ii) SEP + PI, (iii) SEP + BLT + PI, or (iv) classes-as-usual (CAU). Sleep education programs involved 4×50 minute classes (over 4 weeks) based on a Motivational Interviewing framework (Sleep Med 2011;12:246-251). Students in BLT groups attempted a weekend phase advance using portable green light LED glasses (500 nm; 506 lux). Parents of PI groups watched a series of 4 YouTube clips (2-3 minutes in length) outlining their adolescent's learning in class and how they could assist. Students in the CAU groups continued their regular classes., Measurements: Online questionnaires measuring sleep knowledge, sleep patterns (bedtime, sleep latency, total sleep time [TST], etc) and mood at preintervention and postintervention and 6-week follow-up. Intervention groups also completed a motivation-to-change questionnaire and provided qualitative feedback., Results: Improvements in sleep knowledge (d = 0.59-0.88), sleep onset latency (d = 0.45-0.50), TST (d = 0.32-0.57), and mood (d = 0.24-0.46) were observed in all intervention groups relative to the CAU group. Similar improvements were observed in a subgroup of students identified as having delayed sleep timing (ie, sleep knowledge: d = 0.45-0.92; sleep onset latency: d = 0.59-0.82; TST: d = 0.82-1.18). Increases in motivation to regularize out of bedtimes, obtain morning bright light (BLT groups), and avoid sleeping-in on weekends occurred (all P < .005)., Conclusions: This motivational SEP produced meaningful and similar benefits for adolescents in all intervention groups. Longer BLT (ie, over school holidays) and more intensive parental inclusion should be investigated in future studies., (Copyright © 2015 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.)

The present preliminary study aimed to shed light on the mechanisms underlying the development of insomnia. An analogue stressor (i.e., trauma video) was used to prevent presleep cognitive de-arousal. Subsequent changes in nocturnal sleep and sleep-related attentional processing were examined. Thirty-four participants were randomly assigned to either a cognitive arousal (trauma video; age: M = 22.9, SD = 4.3, 6 male, 11 female) or control (pleasant video; age: M = 23.8, SD = 5.8, 7 male, 10 female) condition. Although no significant differences were found for presleep cognitive de-arousal (p = .39), the cognitive arousal group experienced a significant worsening in sleep latency (p = .048, partial η(2) = .12) and an increase in sleep-related attentional bias (p = .032, d = 0.51) following the manipulation. However, changes in sleep and attentional bias were not maintained. Vulnerability to stress did not significantly account for any change in attentional bias, arousal, or sleep. These findings challenge current conceptualizations of the development of insomnia, yet also supporting the notion that good sleep is a default state that protects individuals from sleep disturbance.

The purpose of this review was to quantify the strength of evidence for a directional relationship between sleep disturbance and depression in adolescents. A literature search was conducted to identify research investigating the relationship between sleep disturbance and depression in adolescent samples (12-20 y). Twenty-three studies were identified; 13 explored associations between depression and sleep disturbance; seven examined the prospective role of sleep disturbance in the development of depression; and three investigated the role of adolescent depression in the development of subsequent sleep disturbance. Average weighted mean differences in sleep/depression-related outcome variables were calculated between adolescents with depression, and non-clinical adolescents, or those in remission. Adolescents with depression experienced significantly more wakefulness in bed (sleep onset latency, wake after sleep onset, number of awakenings and sleep efficiency), lighter sleep (more stage 1), and reported more subjective sleep disturbance. Overall effect sizes from longitudinal and treatment studies suggest sleep disturbance acts as a precursor to the development of depression. At follow-up, depressed adolescents had significantly longer sleep onset, more wake after sleep onset, and lower sleep efficiency compared to adolescents who were non-clinical, or had undergone remission. Little support was found for a predictive role of depressive symptoms in the development of sleep disturbance. Based on these findings we propose a model to understand the development of depression from initial sleep disturbance, provide recommendations for clinicians and recommendations for future research., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The paper investigates the impact of text and background color combinations on the legibility of text presented on LCDs. The legibility of 56 elementary color combinations was tested by 308 participants. The first task required the participants to identify 21 uppercase alphabetic characters selected and presented in conformance with a Snellen chart in various color combinations. For each color combination, the number of correctly identified characters was recorded as a visual performance measure. In the second task, participants subjectively rated the legibility of color combinations on a ten-point Likert scale. The results show that neither the Le Courier legibility table nor the CRT legibility table is appropriate for LCDs. A new legibility table is proposed for LCDs where the highest ranked are contrastive color combinations with positive polarity whereas for CRT displays, the highest ranked are contrastive color combinations with negative polarity. The findings of this study can be used to determine the best possible color combinations when developing content displayed on LCDs., (Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.)

The present study investigated adolescent video-game use prior to bedtime and subsequent sleep, working memory and sustained attention performance. Participants were 21 healthy, good-sleeping adolescents (16 male) aged between 15 and 20 years (M = 17.6 years, SD = 1.8). Time spent video-gaming and subsequent sleep was measured across one night in the sleep laboratory. There were significant correlations between time spent video-gaming and sleep and between video-gaming and sustained attention, but not working memory. Sleep duration, in turn, had a significant negative association with sustained attention performance. Mediation analyses revealed that the relationship between video-gaming and sustained attention was fully mediated by sleep duration. These results indicate that video-gaming affected the ability to sustain attention only in as much as it affected sleep. In order to minimise negative consequences of video-game playing, video-games should be used in moderation, avoiding use close to the sleep period, to obviate detriments to sleep and performance., (Copyright © 2014 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.)

Objectives: Sleep disturbance and psychopathology are common during adolescence and are highly prevalent in individuals diagnosed with autism spectrum disorder (ASD). The aim of this study was to investigate relationships between sleep disturbance, psychopathology symptoms, and daytime functioning in adolescents with high-functioning autism spectrum disorder (HFASD) compared to typically developing (TD) adolescents., Methods: Twenty-seven adolescents with HFASD and 27 age- and sex-matched TD adolescents completed questionnaires related to sleep, psychopathology and daytime functioning. Participants also completed a 7-day sleep/wake diary. A subsample of HFASD adolescents (55%) and all the TD adolescents wore an actigraphy monitor concurrently with the sleep diary., Results: Adolescents with HFASD had significantly higher scores for depressed mood, anxiety and pre-sleep arousal compared with TD adolescents and poorer daytime functioning. There were more significant correlations between sleep variables and psychopathology variables, and sleep variables and daytime functioning, in the HFASD group than in the TD group. Standard regression found that sleep variables significantly accounted for 57% of the variance in daytime functioning symptoms of insufficient sleep in the HFASD group, while psychopathology variables accounted for 63% of the variance in daytime functioning., Conclusions: Both sleep disturbance and psychopathology are more prevalent in adolescents with HFASD and are major contributors to poor daytime functioning in these individuals., (Copyright © 2014. Published by Elsevier B.V.)

Objective: Daylight is an important zeitgeber for entraining the circadian rhythm to a 24 h clock cycle, especially within the Polar circle, which has long Polar nights several months each year. Phase delays in sleep timing may occur, but the mean shift is normally small. However, the individual variation in phase shifts is large, implicating moderating factors. Here we examined the role of several self-regulatory variables (mood and fatigue, behavioral habits, and psychological self-regulation) as moderators of seasonality in sleep timing and chronotype., Methods: A sample of 162 young adults (76% females; mean age: females 23.4 years, males 24.3 years) participated in a prospective study across three seasons (September, December, March) in Tromsø/Norway at 69°39′N Sleep diary and sleep/health-related questionnaire data were collected at each time-point., Results: Sleep timing and chronotype were delayed during the dark period (December) compared with brighter photoperiods (September and March). Comparable effects were observed for insomnia, fatigue, mood (depression and anxiety), subjective health complaints, physical activity, and school-related stress. Most importantly, depression and fatigue moderated the degree of seasonal shifting in sleep timing, whereas the other self-regulation indicators did not (ie eating habits, physical activity, and psychological self-regulation)., Conclusion: Seasonality in sleep timing and chronotype was confirmed, and it seems that depressive symptoms during the dark period exacerbate phase-shifting problems for people living in sub-Arctic regions.

Electronic media use is prevalent among adolescent populations, as is the frequency of sleeplessness. One mechanism proposed for technology affecting adolescents' sleep is the alerting effects from bright screens. Two explanations are provided. First, screens emit significant amounts of short-wavelength light (i.e. blue), which produces acute alertness and alters sleep timing. Second, later chronotypes are hypothesised to be hypersensitive to evening light. This study analysed the pre-sleep alertness (GO/NOGO task speed, accuracy; subjective sleepiness), sleep (sleep diary, polysomnography), and morning functioning of 16 healthy adolescents (M = 17.4 ± 1.9 yrs, 56% f) who used a bright tablet screen (80 lux), dim screen (1 lux) and a filtered short-wavelength screen (f.lux; 50 lux) for 1 hr before their usual bedtime in a within-subjects protocol. Chronotype was analysed as a continuous between-subjects factor; however, no significant interactions occurred. Significant effects occurred between bright and dim screens for GO/NOGO speed and accuracy. However, the magnitude of these differences was small (e.g. GO/NOGO speed = 23 ms, accuracy = 13%), suggesting minimal clinical significance. No significant effects were found for sleep onset latency, slow-rolling eye movements, or the number of SWS and REM minutes in the first two sleep cycles. Future independent studies are needed to test short (1 hr) vs longer (>2 hrs) screen usage to provide evidence for safe-to-harmful levels of screenlight exposure before adolescents' usual bedtime.

Objective: Catastrophising is a repetitive cognitive process related to sleep disturbance in adult insomnia patients. More recently catastrophising has been associated with increased sleep disturbances in community samples of children and adolescents, with this association mediated by anxiety and depression. However, there currently is no evidence of these processes outside of community samples; impeding our ability to draw clinical conclusions. Knowledge on such dysfunctional cognitive processes in adolescents experiencing sleep disturbance would be clinically beneficial in aetiology and intervention. Our research examined the link between catastrophising, anxiety, depression and sleep latency in a sample of sleep-disordered adolescents. We also explored specific catastrophising themes which may impact the sleep latency of these adolescents., Method: Forty adolescents (age=15.1±1.5 years, 53% boys) diagnosed with delayed sleep phase disorder completed a 7-day sleep diary, along with measures of anxiety and depression and a catastrophising interview with a trained sleep therapist., Results: Several catastrophisation themes were generated, the most common concerning interpersonal and performance aspects of school. Bootstrapping analyses showed depression did not mediate the relationship between catastrophising and sleep; however, an indirect relationship was found between catastrophising, anticipatory anxiety, and sleep latency., Conclusion: These findings have implications for the role of dysfunctional thinking in prolonging sleep onset for adolescents and providing a clinical framework for health professionals when assessing and treating adolescents with delayed sleep timing., (Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.)

Study Objectives: To describe the technology use and sleep quality of Americans, and the unique association between technology use and sleep disturbances., Methods: Interviews were conducted via random digit dialing (N = 750) or the Internet (N = 758). 1,508 Americans (13-64 years old, 50% males) matched to 2009 U.S. Census data provided complete interviews. The sample was further divided into adolescents (13-18 years, N = 171), young adults (19-29 years, N = 293), middle-aged adults (30-45 years, N = 469), and older adults (46-64 years, N = 565) to contrast different generations' technology use. Participants answered a 47-item semi-structured survey, including questions about their sleep habits, and the presence and use of technology in the hour before bed in the past 2 weeks., Results: Nine of 10 Americans reported using a technological device in the hour before bed (e.g., TVs the most popular; 60%). However, those under 30 years of age were more likely to use cell phones (72% of adolescents, 67% of young adults) than those over 30 years (36% of middle-aged, and 16% of older adults). Young adults' sleep patterns were significantly later than other age groups on both weekdays and weekend nights. Unlike passive technological devices (e.g., TV, mp3 music players), the more interactive technological devices (i.e., computers/laptops, cell phones, video game consoles) used in the hour before bed, the more likely difficulties falling asleep (β = 9.4, p < 0.0001) and unrefreshing sleep (β = 6.4, p < 0.04) were reported., Conclusions: Technology use near bedtime is extremely prevalent in the United States. Among a range of technologies, interactive technological devices are most strongly associated with sleep complaints.

The present study developed and tested a theoretical model examining the inter-relationships among sleep duration, sleep quality, and circadian chronotype and their effect on alertness, depression, and academic performance. Participants were 385 adolescents aged 13-18 years (M = 15.6, SD = 1.0; 60% male) were recruited from eight socioeconomically diverse high schools in South Australia. Participants completed a battery of questionnaires during class time and recorded their sleep patterns in a sleep diary for 8 days. A good fit was found between the model and the data (χ(2)/df = 1.78, CFI = .99, RMSEA = .04). Circadian chronotype showed the largest association with on adolescent functioning, with more evening-typed students reporting worse sleep quality (β = .50, p < .001) and diminished alertness (β = .59, p < .001). Sleep quality was significantly associated with poor outcomes: adolescents with poorer sleep quality reported less sleep on school nights (β = -.28, p < .001), diminished daytime alertness (β = .33, p < .001), and more depressed mood (β = .47, p < .001). Adolescents with poor sleep quality and/or more evening chronotype were also more likely to report worse grades, through the association with depression. Sleep duration showed no direct effect on adolescent functioning. These results identified the importance of two lesser-studied aspects of sleep: circadian chronotype and sleep quality. Easy-to-implement strategies to optimize sleep quality and maintain an adaptive circadian body clock may help to increase daytime alertness, elevate mood, and improve academic performance., (Copyright © 2013 The Foundation for Professionals in Services for Adolescents. All rights reserved.)

The currently assumed aetiology for delayed sleep phase disorder (DSPD) is a delay of the circadian system. Clinicians have sought to use bright light therapy, exogenous melatonin or chronotherapy to correct the disorder. However, these treatments have achieved unreliable outcomes for DSPD patients and, as such, one suggestion has been that the disorder may be caused by a longer than normal circadian rhythm period length (i.e. tau). The present study investigated this premise using a 78-h ultradian, ultra-short sleep-wake cycle. This constant bedrest routine was used to simulate a series of 1-h long 'days' by alternating 20-min sleep opportunities and 40 min of enforced wakefulness. Thirteen participants were recruited for the study including, six people diagnosed with DSPD according to the International Classification of Sleep Disorders-2 [mean age = 22.0, standard deviation (SD) = 3.3] and seven good sleepers (mean age = 23.1, SD = 3.9) with normal sleep timing. The DSPD participants' core temperature rhythm tau (mean = 24 h 54 min, SD = 23 min) was significantly longer (t = -2.33, P = 0.04, Cohen's d = 1.91) than the good sleepers' (mean 24 h 29 min, SD = 16 min). The temperature rhythm of the DSPD participants delayed more rapidly (i.e. >25 min day(-1) ) than the good sleepers'. These findings provide an explanation for the difficulty that DSPD patients have in phase advancing to a more conventional sleep time and their frequent relapse following treatment. The outcomes of this study support a vigorous and continued application of chronobiological and behavioural therapies to entrain DSPD patients to their desired earlier sleep times., (© 2013 European Sleep Research Society.)

Purpose of Review: For over 30 years, delayed sleep phase disorder (DSPD) has been defined as a debilitating sleep condition. Recently, there is more awareness of DSPD in young people, yet considerable information is needed to understand its cause and treatment. This review describes the latest research findings describing the clinical features, cause, and treatment of DSPD., Recent Findings: The prevalence of DSPD in adolescents and young adults ranges from 1 to 16%. The impact on the individuals is significant, particularly in the domains of school/work performance and mental health. We describe various contributing factors including reduced homeostatic sleep pressure, a lengthened and delayed circadian rhythm, insensitivity to clock-resetting morning light, and heightened cognitive activity. Evening melatonin administration as a sole treatment appears promising, as is a combination of cognitive-behavior therapy and morning bright light., Summary: Recent findings suggest clinicians to be aware of the clinical features (i.e., significant daytime sleepiness, anxiety and depression symptoms, potential for school dropout) of DSPD, as several biological features underpinning this disorder are unseen in clinical settings. We advise clinicians to become familiar with exogenous evening melatonin administration, and cognitive and behavioral techniques to simultaneously treat the delayed circadian rhythm and associated sleep-onset insomnia.

Objectives: To examine the efficacy of self-report and parental report of adolescent sleep problems and compare these findings to the incidence of adolescents who fulfill clinical criteria for a sleep problem. Sleep and daytime functioning factors that predict adolescents' self-identification of a sleep problem will also be examined., Method: 308 adolescents (aged 13-17 years) from eight socioeconomically diverse South Australian high schools participated in this study. Participants completed a survey battery during class time, followed by a 7-day Sleep Diary and the Flinders Fatigue Scale completed on the final day of the study. Parents completed a Sleep, Medical, Education and Family History Survey., Results: The percentage of adolescents fulfilling one or more of the criteria for a sleep problem was inordinately high at 66%. Adolescent self-reporting a sleep problem was significantly lower than the adolescents who had one or more of the clinical criteria for a sleep problem (23.1% vs. 66.6%; χ(2) = 17.46, p<.001). Parental report of their adolescent having a sleep problem was significantly lower than adolescent self-report (14.3% vs. 21.1%, p<.001). Adolescents who reported unrefreshing sleep were 4.81 times more likely to report a sleep problem. For every hour that bedtime was delayed, the odds of self-reporting a sleep problem increased by 1.91 times, while each additional 10 minutes taken to fall asleep increased the odds 1.40 times., Conclusion: While many adolescents were found to have sleep patterns indicative of a sleep problem, only a third of this number self-identify having a sleep problem, while only a sixth of this number are indicated by parental report. This study highlights important features to target in future sleep education and intervention strategies for both adolescents and parents.

Study Objectives: To establish the extent to which the developmental changes in sleep timing experienced by Australian adolescents meet the International Classification of Sleep Disorders (ICSD-2) diagnostic criteria for delayed sleep phase disorder (DSPD), and whether adolescents with DSPD engage in poorer lifestyle choices, and are more impaired compared to good sleeping adolescents., Methods: Three-hundred seventy-four Australian adolescents (mean age 15.6 years, SD 1.0) participants completed a 7-day sleep diary, wore wrist actigraphy, and completed a battery of questionnaires to assess DSPD criteria., Results: The ICSD-2 criteria for DSPD were met by 1.1% (N = 4) of the adolescents sampled. The majority of adolescents (51.9%, N = 194) met one criterion, 14% (N = 52) of the adolescents met 2 criteria, while 33.2% (N = 124) did not fulfill any DSPD criteria. Despite having significantly delayed sleep timing, adolescents who met all criteria for DSPD reported similar lifestyle habits and daytime functioning. However, there were trends for greater alcohol and caffeine consumption, less sport participation, yet more time spent on extracurricular activities (i.e., learning to play a musical instruments for adolescents with DSPD., Conclusions: Despite the majority of adolescents reporting DSPD symptoms, only a small minority met full diagnostic criteria. Adolescents with DSPD reported similar lifestyle habits and daytime functioning to those with some or no symptoms. Future investigations of non-school-attending DSPD adolescents are needed to confirm the trends for lifestyle behaviors found in the present study.

Objective: To investigate the sleep patterns and disturbances in a pure sample of adolescents with high-functioning autism spectrum disorder (HFASD)., Method: Adolescents completed a sleep questionnaire battery and a 7 d sleep diary. Actigraphic data were collected from a sub-sample of participants (55%) with HFASD and all typically developing (TD) adolescents., Results: Adolescents with HFASD were three times more likely to report a sleep problem than their TD peers (46.2% vs. 14.8%). Adolescents with HFASD had decreased sleep efficiency (diary) (p = 0.04, η(2 )= 0.10), and more fatigue (p = 0.002, η(2 )= 0.18) compared with TD adolescents. While TD adolescents generally experienced one symptom of insomnia, adolescents with HFASD were likely to experience two or three symptoms of insomnia (p = 0.02, V = 0.36)., Conclusion: The findings suggest that adolescents with HFASD show a continuation of the maladaptive sleep patterns as seen in children with an autism spectrum disorder and these sleep disturbances are associated with increased daytime sleepiness.

Study Objective: To test whether sleep duration on school nights differs between adolescents in Australia and the United States and, if so, whether this difference is explained by cultural differences in school start time, parental involvement in setting bedtimes, and extracurricular commitments., Participants: Three hundred eighty-five adolescents aged 13 to 18 years (M = 15.57, SD = 0.95; 60% male) from Australia and 302 adolescents aged 13 to 19 years (M = 16.03, SD = 1.19; 35% male) from the United States., Methods: Adolescents completed the School Sleep Habits Survey during class time, followed by an 8-day sleep diary., Results: After controlling for age and gender, Australian adolescents obtained an average of 47 minutes more sleep per school night than those in the United States. Australian adolescents were more likely to have a parent-set bedtime (17.5% vs. 6.8%), have a later school start time (8:32 a.m. vs. 7:45 a.m.), and spend less time per day on extracurricular commitments (1 h 37 min vs. 2 h 41 min) than their U.S. peers. The mediating factors of parent-set bedtimes, later school start times, and less time spent on extracurricular activities were significantly associated with more total sleep., Conclusions: In addition to biological factors, extrinsic cultural factors significantly affect adolescent sleep. The present study highlights the importance of a cross-cultural, ecological approach and the impact of early school start times, lack of parental limit setting around bedtimes, and extracurricular load in limiting adolescent sleep.

Pathological video-gaming, or its proposed DSM-V classification of "Internet Use Disorder", is of increasing interest to scholars and practitioners in allied health disciplines. This systematic review was designed to evaluate the standards in pathological video-gaming instrumentation, according to Cicchetti (1994) and Groth-Marnat's (2009) criteria and guidelines for sound psychometric assessment. A total of 63 quantitative studies, including eighteen instruments and representing 58,415 participants, were evaluated. Results indicated that reviewed instrumentation may be broadly characterized as inconsistent. Strengths of available measures include: (i) short length and ease of scoring, (ii) excellent internal consistency and convergent validity, and (iii) potentially adequate data for development of standardized norms for adolescent populations. However, key limitations included: (a) inconsistent coverage of core addiction indicators, (b) varying cut-off scores to indicate clinical status, (c) a lack of a temporal dimension, (d) untested or inconsistent dimensionality, and (e) inadequate data on predictive validity and inter-rater reliability. An emerging consensus suggests that pathological video-gaming is commonly defined by (1) withdrawal, (2) loss of control, and (3) conflict. It is concluded that a unified approach to assessment of pathological video-gaming is needed. A synthesis of extant research efforts by meta-analysis may be difficult in the context of several divergent approaches to assessment., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Video-gaming is an increasingly prevalent activity among children and adolescents that is known to influence several areas of emotional, cognitive and behavioural functioning. Currently there is insufficient experimental evidence about how extended video-game play may affect adolescents' sleep. The aim of this study was to investigate the short-term impact of adolescents' prolonged exposure to violent video-gaming on sleep. Seventeen male adolescents (mean age = 16 ± 1 years) with no current sleep difficulties played a novel, fast-paced, violent video-game (50 or 150 min) before their usual bedtime on two different testing nights in a sleep laboratory. Objective (polysomnography-measured sleep and heart rate) and subjective (single-night sleep diary) measures were obtained to assess the arousing effects of prolonged gaming. Compared with regular gaming, prolonged gaming produced decreases in objective sleep efficiency (by 7 ± 2%, falling below 85%) and total sleep time (by 27 ± 12 min) that was contributed by a near-moderate reduction in rapid eye movement sleep (Cohen's d = 0.48). Subjective sleep-onset latency significantly increased by 17 ± 8 min, and there was a moderate reduction in self-reported sleep quality after prolonged gaming (Cohen's d = 0.53). Heart rate did not differ significantly between video-gaming conditions during pre-sleep game-play or the sleep-onset phase. Results provide evidence that prolonged video-gaming may cause clinically significant disruption to adolescent sleep, even when sleep after video-gaming is initiated at normal bedtime. However, physiological arousal may not necessarily be the mechanism by which technology use affects sleep., (© 2012 European Sleep Research Society.)

Aim: Adolescent sleep patterns vary between countries, and these differences influence adolescent functioning and well-being. The present study provides data on the sleep and well-being of Australian adolescents., Methods: 385 adolescents aged 13-18 years were recruited from 8 South Australian schools spanning the socio-economic spectrum. Adolescents completed survey battery during class time at school, followed by a 7-day sleep diary., Results: Australian adolescents, on average, obtained inadequate sleep across the school week. Adolescents commonly reported difficulty initiating sleep, unrefreshing sleep, and the subjective feeling of restless legs. Problematic levels of sleepiness, fatigue, depressed mood and anxiety were highly prevalent. Later bedtimes, longer sleep onset latencies, and shorter sleep duration were significantly associated with aspects of poor daytime functioning., Conclusion: These results add to our knowledge of adolescent sleep and well-being worldwide. They also highlight the need for greater attention to sleep during this phase of development, when future behaviors and outcomes are being shaped., (Copyright © 2012 The Foundation for Professionals in Services for Adolescents. All rights reserved.)

Excessive and potentially addictive use of the Internet among children and adolescents has emerged as a major concern in recent times. Internet addiction is often conceptualized as an impulse control disorder, with features similar to pathological gambling. However, there remains considerable debate about the core components, etiological processes, course, and maintaining factors of the disorder. This article presents a case study of a 16-year-old male with generalized pathological Internet use. Critical issues relevant to case conceptualization, assessment, and choice of therapy are examined. Although the evidence base is limited in this emerging area of clinical psychology, we provide a summary of empirically supported cognitive-behavioral techniques for Internet addiction., (© 2012 Wiley Periodicals, Inc.)

Although adolescents often experience insufficient and/or poor sleep, sleep variables such as total sleep time do not account for individuals' sleep need and sleep debt and may therefore be an inadequate representation of adolescents' sleep problems and its daytime consequences. This problem can be overcome by using the Chronic Sleep Reduction Questionnaire (CSRQ), an assessment tool that measures symptoms of chronic sleep reduction and therefore accounting for sleep need and sleep debt. The present study aims at developing an English version of the CSRQ and assesses the reliability and validity of the Dutch and the English CSRQ version. The CSRQ was administered in large Dutch (n = 166, age = 15.2 ± 0.57 years, 28% male) and Australian (n = 236, age = 15.5 ± 0.99 years, 65% males) samples. Subjective sleep variables were measured with surveys and sleep diaries of five school nights. Additionally, sleep of the same five nights was monitored with actigraphy. Both CSRQ versions showed good psychometric properties concerning their reliability (Dutch: α = 0.85; English: α = 0.87) and validity as the same overall structure of the two CSRQ versions and significant correlations with subjective and objective sleep variables were found. School grades were related to chronic sleep reduction, whereas the relationship between grades and other sleep variables was weak or absent. These results highlight the idea that chronic sleep reduction may be a better indicator of adolescents' insufficient and/or poor sleep than other sleep variables such as total sleep time., (© 2012 European Sleep Research Society.)

This paper reviews 15 adolescent (10-19 yrs) studies that have directly investigated the effects of shortened sleep duration on overweight and obesity. The research studies included in this review inconsistently found significant effects between shortened sleep duration and weight status. This heterogeneity in study findings largely resulted from variability in study design, gender, and the method used to measure sleep duration. Consequently, due to the conflicting research findings, it remains inconclusive as to whether shortened sleep is a risk factor for overweight or obesity during adolescence. This review also identified methodological limitations within the literature and presented alternative methodologies for future research. First, sleep duration measures were identified that had questionable reliability and were possibly less accurate than other recommended sleep measurements. Second, 92% of cross-sectional studies found a significant relationship, yet 0% of prospective studies did. Third, the vast majority of studies neglected to statistically adjust for co-contributions from depression, and approximately half of the studies considered the role of physical activity. Recommendations for future research directions are presented which may help to clarify the conflicting findings and address the methodological concerns identified within this topical area., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Study Objectives: Many studies of adolescent insomnia use experience of insomnia-like symptoms to categorize "caseness." This is likely to lead to inflated prevalence and may have important ramifications for the research using individual symptoms to operationalize insomnia. The aim of the present study was to contrast the occurrence of insomnia symptoms with cases of insomnia diagnosed using criteria from the fourth edition of the Diagnostic and Statistical Manual for Mental Disorders (DSM-IV) and the second edition of the International Classification of Sleep Disorders (ICSD-II) in a sample of Australian adolescents., Methods: Data were collected from 384 representative Australian adolescents aged 13-18 years old (59% male). During school hours, adolescents completed a comprehensive questionnaire battery targeting insomnia criteria and then completed a sleep diary for 7 days., Results: Insomnia symptoms were frequently reported by adolescents (e.g., 34.6% for frequent sleep-related daytime consequences). The proportion of adolescents meeting the diagnositc criteria for insomnia was much smaller: 10.9% of adolescents were classified as having General Insomnia using ICSD-II criteria, and 7.8% were classified as having Primary Insomnia according to DSM-IV criteria. ICSD-II Psychophysiological Insomnia was observed in 3.4% of adolescents. Insomnia diagnoses did not vary according to age, gender, school grade, or socioeconomic status. Using the ICSD-II criteria for General Insomnia resulted in a significantly higher number of insomnia diagnoses than did DSM-IV criteria for Primary Insomnia (p < 0.001) and ICSD-II Psychophysiological Insomnia (p < 0.001)., Conclusions: These results reveal that approximately 3 adolescents in the average classroom of 30 are likely to meet the diagnostic criteria for insomnia, while many more will have insomnia symptoms. There were significant differences in prevalence rates, depending on how insomnia was operationalized.

Objective: To evaluate cognitive-behavior therapy plus bright light therapy (CBT plus BLT) for adolescents diagnosed with delayed sleep phase disorder (DSPD)., Design: Randomized controlled trial of CBT plus BLT vs. waitlist (WL) control with comparisons at pre- and post-treatment. There was 6-month follow-up for the CBT plus BLT group only., Setting: Flinders University Child & Adolescent Sleep Clinic, Adelaide, South Australia., Patients: 49 adolescents (mean age 14.6 ± 1.0 y, 53% males) diagnosed with DSPD; mean chronicity 4 y 8 months; 16% not attending school. Eighteen percent of adolescents dropped out of the study (CBT plus BLT: N = 23 vs. WL: N = 17)., Interventions: CBT plus BLT consisted of 6 individual sessions, including morning bright light therapy to advance adolescents' circadian rhythms, and cognitive restructuring and sleep education to target associated insomnia and sleep hygiene., Measurements and Results: DSPD diagnosis was performed via a clinical interview and 7-day sleep diary. Measurements at each time-point included online sleep diaries and scales measuring sleepiness, fatigue, and depression symptoms. Compared to WL, moderate-to-large improvements (d = 0.65-1.24) were found at post-treatment for CBT plus BLT adolescents, including reduced sleep latency, earlier sleep onset and rise times, total sleep time (school nights), wake after sleep onset, sleepiness, and fatigue. At 6-month follow-up (N = 15), small-to-large improvements (d = 0.24-1.53) continued for CBT plus BLT adolescents, with effects found for all measures. Significantly fewer adolescents receiving CBT plus BLT met DPSD criteria at post-treatment (WL = 82% vs. CBT plus BLT = 13%, P < 0.0001), yet 13% still met DSPD criteria at the 6-month follow-up., Conclusions: CBT plus BLT for adolescent DSPD is effective for improving multiple sleep and daytime impairments in the immediate and long-term. Studies evaluating the treatment effectiveness of each treatment component are needed., Clinical Trial Information: Australia-New Zealand Trials Registry Number: ACTRN12610001041044.

Although there is ongoing debate concerning the clinical status of Internet addiction, and the quality of the extant literature in this emerging field is not optimal, several clinical trials of both pharmacological and psychological treatments for Internet addiction have been published in recent years. A systematic review investigating the reporting quality of eight treatment studies is presented. Reporting quality was defined according to the 2010 Consolidating Standards of Reporting Trials (CONSORT) statement. An evaluation of the reviewed studies highlighted several key limitations, including (a) inconsistencies in the definition and diagnosis of Internet addiction, (b) a lack of randomization and blinding techniques, (c) a lack of adequate controls or other comparison groups, and (d) insufficient information concerning recruitment dates, sample characteristics, and treatment effect sizes. It is concluded that improvements in future studies' design and reporting would be of significant benefit to both researchers and clinicians, and to the overall positioning of Internet addiction in the behavioral addiction field., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Study Objectives: To determine the proportion of adolescents whose bedtime is set by their parents and to evaluate whether parent-set bedtimes are associated with earlier bedtimes, more sleep, and better daytime functioning., Participants: 385 adolescents aged 13-18 years (mean = 15.6, SD = 0.95; 60% male) from 8 socioeconomically diverse schools in South Australia., Measurements and Methods: Adolescents completed the School Sleep Habits Survey during class time and then completed an 8-day Sleep Diary. The Flinders Fatigue Scale was completed on the final day of the study., Results: 17.5% of adolescents reported a parent-set bedtime as the main factor determining their bedtime on school nights. Compared to adolescents without parent-set bedtimes, those with parent-set bedtimes had earlier bedtimes, obtained more sleep, and experienced improved daytime wakefulness and less fatigue. They did not differ significantly in terms of time taken to fall asleep. When parent-set bedtimes were removed on weekends, sleep patterns did not significantly differ between groups., Conclusions: Significant personal and public health issues, such as depression and accidental injury and mortality, are associated with insufficient sleep. Converging biological and psychosocial factors mean that adolescence is a period of heightened risk. Parent-set bedtimes offer promise as a simple and easily translatable means for parents to improve the sleep and daytime functioning of their teens.

Chronic sleep problems can lead to the development of Behavioural Insomnia of Childhood - a sleep disorder involving problematic sleep-onset associations (i.e., parental presence), and resulting in impairments for children and family members. The aim of the present paper was to perform a controlled evaluation of cognitive-behaviour therapy (CBT) for Behavioural Insomnia. 42 children (M = 9.3 ± 1.9 yrs, range 7-13 yrs, 18f, 24 m) were randomised to CBT (N = 21) or waitlist control (N = 21). CBT consisted of 6 sessions, and combined behavioural sleep medicine techniques (e.g., sleep restriction) with anxiety treatment techniques (e.g., cognitive restructuring). Compared to waitlist controls, children receiving CBT showed significant improvements in sleep latency, wake after sleep onset, and sleep efficiency (all p ≤ .003), but not total sleep time (p > .05). CBT was also associated with a reduction in problematic sleep associations (p ≤ .001), child-reported total and separation anxiety (both p ≤ .01), with all gains being maintained 6 months post-treatment. This is the first controlled study to demonstrate that multi-component CBT can be effective for the sleep, insomnia, and anxiety symptoms of Behavioural Insomnia of Childhood in school-aged children. Future research is needed to ascertain active treatment components., (Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.)

Objective: The current study aimed to develop and evaluate a motivational school-based intervention for adolescent sleep problems., Methods: The intervention was implemented in three co-educational secondary schools in Adelaide, South Australia. Two year-11 Psychology classes from each school participated, with one as the intervention class (N=53) and one as the control class (N=51). Students in the intervention classes attended four 50-min sleep education classes, held once per week. The lessons were modified from those of Moseley and Gradisar [23] to incorporate a motivational interviewing framework. Students completed an online questionnaire battery measuring school day and weekend sleep parameters, daytime sleepiness, and depression at pre- and post-program and follow-up, and completed motivation to change questionnaires during the program., Results: Students in the intervention group significantly increased their knowledge about sleep relative to the control group (p=0.001). During the intervention, students' motivation to regularize their out-of-bed times improved (p=0.03), and there was a trend towards improved motivation to increase average total sleep time (p=0.11). But despite improvements in sleep and daytime functioning for adolescents in the program group (p<0.05), these changes were not significantly different from the control group (all p>0.05)., Conclusions: School-based interventions are promising for educating adolescents about sleep. Future programs should translate increased motivation into long-term behavioral change. The identification of barriers and support to assist this change is recommended., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Adolescent sleep health is becoming increasingly recognized internationally as a significant concern, with many countries reporting high incidences of sleep disturbance in our youth. Notwithstanding the value of findings obtained from each large-scale survey of adolescent sleep performed within individual countries, the field lacks synthesis and analysis of adolescent sleep studies into a single review. This review presents findings from a meta-analysis of 41 surveys of worldwide adolescent sleep patterns and problems published in the last decade (1999-2010). Sleep patterns tended to delay with increasing age, restricting school-night sleep. Notably, Asian adolescents' bedtimes were later than peers from North America and Europe, resulting in less total sleep time on school nights and a tendency for higher rates of daytime sleepiness. Weekend sleep data were generally consistent worldwide, with bedtimes 2+ hours later and more total sleep time obtained. We note a worldwide delayed sleep-wake behavior pattern exists consistent with symptoms of Delayed Sleep Phase Disorder, which may be exacerbated by cultural factors. Recommendations for future surveys of adolescent sleep patterns are discussed and provided in light of current methodological limitations and gaps in the literature., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Electronic media have often been considered to have a negative impact on the sleep of children and adolescents, but there are no comprehensive reviews of research in this area. The present study identified 36 papers that have investigated the relationship between sleep and electronic media in school-aged children and adolescents, including television viewing, use of computers, electronic gaming, and/or the internet, mobile telephones, and music. Many variables have been investigated across these studies, although delayed bedtime and shorter total sleep time have been found to be most consistently related to media use. A model of the mechanisms by which media use may affect sleep is presented and discussed as a vehicle for future research., (Copyright 2010 Elsevier B.V. All rights reserved.)

Study Objectives: Video-game use before bedtime has been linked with poor sleep outcomes for adolescents; however, experimental evidence to support this link is sparse. The present study investigated the capacity of presleep video-game playing to extend sleep latency and reduce subjective feelings of sleepiness in adolescents. The arousing psychophysiologic mechanisms involved and the impact of presleep video-game playing on sleep architecture were also explored., Method: Thirteen male adolescent "evening types" (mean age = 16.6 years, SD = 1.1) participated in a counterbalanced, within-subjects design with experimental (active video gaming) and control (passive DVD watching) conditions. The experiment was conducted in the Flinders University Sleep Research Laboratory., Results: Relative to the control condition, presleep video-game playing increased sleep-onset latency (Z= 2.45, p= .01) and reduced subjective sleepiness (Z = 2.36, p = .02)-but only slightly. Video gaming was related to changes in cognitive alertness (as measured by a power: p < 0.01) but not physiologic arousal (as measured by heart rate: p > 0.05). Contrary to previous findings, sleep architecture was unaffected (both rapid eye movement and slow wave sleep: p > 0.05)., Conclusions: Results suggest the direct effect of presleep video-game playing on adolescent sleep may be more modest than previously thought, suggesting that surveys linking stimulating presleep activities to poor sleep need substantiating with empirical evidence.

The link between sleep hygiene and adolescent sleep is well documented, though evidence suggests contributions from other factors, particularly the family environment. The present study examined whether sleep hygiene mediated the relationship between family disorganization and self-reported sleep onset latency, total sleep time, and daytime sleepiness in adolescents. Participants were 217 adolescents, aged 13 to 18 (M = 14.9, SD = 1.0) years, (43% male), recruited from four high schools in South Australia. Sleep hygiene fully mediated the relationship between family disorganization and sleep onset latency (z = 2.77, p < .01) and daytime sleepiness (z = 3.47, p < .01). Only partial mediation was evident for total sleep time (z = 2.50, p < .05). These findings suggest that consideration should be given to the family environment when assessing sleep disturbance in adolescents, and subsequently implementing interventions.

Childhood sleep problems have been associated with a range of adverse cognitive and academic outcomes, as well as increased impulsivity and emotional disorders such as anxiety and depression. The aim of the study was to examine subjective reports of sleep-related problems in children with anxiety disorders during school and weekend nights. Thirty-seven children with clinically-diagnosed anxiety disorders and 26 non-clinical children aged 7-12 years completed an on-line sleep diary to track sleep patterns across school nights and weekend nights. Anxious children reported going to bed significantly later (p=0.03) and had significantly less sleep (p=0.006) on school nights compared to non-anxious children. No significant differences in sleep onset latency, number of awakenings or time awake during the night, daytime sleepiness, or fatigue were found between the two groups. On the weekends, anxious children fell asleep quicker and were less awake during the night than on weeknights. School-aged anxiety disordered children showed a sleep pattern that differs from their non-anxious peers. Although the mean 30 min less sleep experienced by anxious children may initially seem small, the potential consequences on daytime performance from an accumulation of such a sleep deficit may be significant, and further investigation is warranted.

Sleepiness and sleep propensity are strongly influenced by our circadian clock as indicated by many circadian rhythms, most commonly by that of core body temperature. Sleep is most conducive in the temperature minimum phase, but is inhibited in a "wake maintenance zone" before the minimum phase, and is disrupted in a zone following that phase. Different types of insomnia symptoms have been associated with abnormalities of the body temperature rhythm. Sleep onset insomnia is associated with a delayed temperature rhythm presumably, at least partly, because sleep is attempted during a delayed evening wake maintenance zone. Morning bright light has been used to phase advance circadian rhythms and successfully treat sleep onset insomnia. Conversely, early morning awakening insomnia has been associated with a phase advanced temperature rhythm and has been successfully treated with the phase delaying effects of evening bright light. Sleep maintenance insomnia has been associated not with a circadian rhythm timing abnormality, but with nocturnally elevated core body temperature. Combination of sleep onset and maintenance insomnia has been associated with a 24-h elevation of core body temperature supporting the chronic hyper-arousal model of insomnia. The possibility that these last two types of insomnia may be related to impaired thermoregulation, particularly a reduced ability to dissipate body heat from distal skin areas, has not been consistently supported in laboratory studies. Further studies of thermoregulation are needed in the typical home environment in which the insomnia is most evident.

Study Objectives: To evaluate the psychometric properties and clinical significance of a new scale for measuring daytime fatigue associated with insomnia: The Flinders Fatigue Scale (FFS)., Methods: The 7-item FFS was used in two separate studies. Study 1 was an on-line validation study involving 1093 volunteers (mean [SD] age = 38.6 [14.7] y, 626 poor sleepers, 467 good sleepers) in a cross-sectional design; Study 2 investigated the clinical sensitivity of the FFS on 113 insomnia patients (mean [SD] age = 48.3 [15.0] y) in response to a 5-week cognitive-behavior therapy for insomnia (CBT-I) program., Results: The FFS had an internal consistency of 0.91; it comprised a single factor, accounting for 67% of the total variance. Poor sleepers in Study 1 scored significantly higher than good sleepers on the FFS (p < 0.0001). In Study 2, significant reductions in FFS scores were found in response to CBT-I (p < 0.0001). These reductions in fatigue correlated with improvements on subjective sleep parameters (all p < 0.0001). The FFS showed good discriminant validity with the Epworth Sleepiness Scale., Conclusions: The Flinders Fatigue Scale is a brief, clinically sensitive measure with strong psychometric properties.

The aim of this study was to assess the effectiveness of Intensive Sleep Retraining, a novel, short duration behavioural therapy in treating chronic primary insomnia. Seventeen consecutive volunteers from the general public (mean age = 39.1 years), meeting selection criteria for chronic primary insomnia participated in the treatment study. The study was performed as a case replication series. Assessment involved sleep diary, actigraph and questionnaire measures of sleep and daytime functioning for a period of 2 weeks prior to, immediately after, and 6 weeks following the treatment. Treatment involved a single night of sleep deprivation, facilitating short sleep latencies (mean: 6.9 min) to a series of 50 brief nap opportunities. Following treatment, Sleep Onset Latency significantly decreased by a mean of 30.5 min (SD = 28.3), Wake Time after Sleep Onset significantly decreased by a mean of 28 min (SD = 34.0), and Total Sleep Time significantly increased by 64.6 min (SD = 45.5). Significant improvements were also seen in the daytime functioning and psychological measures of fatigue and vigour, cognitive sleep anticipatory anxiety and self-efficacy for sleep. This brief therapy was effective in improving sleep and some daytime functioning and psychological questionnaire measures. These improvements were maintained up to 2 months following the treatment weekend. Further exploration of this brief therapy is needed, with larger, randomized, placebo-controlled trials over longer follow-up periods, and in comparison to other traditional therapies for insomnia.

For good sleepers, distal skin temperatures (e.g., hands and feet) have been shown to increase when sleep is attempted. This process is said to reflect the body's action to lose heat from the core via the periphery. However, little is known regarding whether the same process occurs for insomniacs. It would be expected that insomniacs would have restricted heat loss due to anxiety when attempting sleep. The present study compared the finger skin temperature changes when sleep was attempted for 11 chronic primary insomniacs [mean age = 40.0 years (SD 13.3)] and 8 good sleepers [mean age = 38.6 years (SD 13.2)] in a 26-h constant routine protocol with the inclusion of multiple-sleep latency tests. Contrary to predictions, insomniacs demonstrated increases in finger skin temperature when attempting sleep that were significantly greater than those in good sleepers (P = 0.001), even though there was no significant differences in baseline finger temperature (P = 0.25). These significant increases occurred despite insomniacs reporting significantly greater sleep anticipatory anxiety (P < 0.0008). Interestingly, the core body temperature mesor of insomniacs (37.0 +/- 0.2 degrees C) was significantly higher than good sleepers (36.8 +/- 0.2 degrees C; P = 0.03). Whether insomniacs could have impaired heat loss that is masked by elevated heat production is discussed.

Skin temperature circadian rhythms have been explored relatively recently. It has been suggested that distal and proximal skin temperature changes play a role in the regulation of the core temperature circadian rhythm and sleepiness. The authors investigated the circadian finger and core temperature rhythms in conjunction with the circadian rhythms of subjective and objective sleepiness. Fourteen healthy, young, good sleepers participated in a modified constant-routine procedure in which palmar finger temperature, rectal temperature, subjective sleepiness, and objective sleep latency were measured half-hourly across a 48-h period of enforced wakeful bed rest. Individual curves were adjusted to the group mean temperature minimum time of 0500 h and averaged to create the 4 mean curves. The 5 possible cross-correlation curves between these 4 measures were calculated for half-hourly phase lags from 12 h before to 12 h after the group mean core temperature minimum time. Maximum cross-correlations for each curve suggested that finger temperature preceded core temperature by 3 h (r = -0.22), and subjective sleepiness followed core temperature by 0.5 h (r = -0.33) and objective sleepiness by 2 h (r = 0.29). Although these data are correlational, they are consistent with the notion that finger temperature changes drive core temperature changes, which determine changes of subjective and objective sleepiness.

A resurgence in the field of sleep initiation and thermoregulation has seen a number of investigators reporting relatively gradual increases in distal skin temperatures of the hands and feet prior to sleep onset at typical bedtimes. The present study extends upon prior knowledge by investigating whether: (1) this is a change of distal skin temperature triggered specifically by the attempt to fall asleep and (2) whether this relationship holds for various phases of the circadian rhythm whenever sleep is attempted. Fourteen healthy good sleepers participated in a modified 45-h constant routine (CR) with multiple sleep onset latency tests (MSLT) conducted every half hour. After a brief decrease of finger temperature associated with small postural adjustments at the beginning of each sleep latency test, finger temperature showed rapid (0.8 degrees C min-1) increases of 1-3 degrees C leading up to the onset of sleep. This rapid increase of finger temperature was relatively consistent across the 45-h CR, despite very significant circadian variation of the pre-MSLT baseline finger temperature and homeostatic decrease of sleep latency.