***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background : Our view is that sleep disturbance may be a contributory causal factor in the development and maintenance of psychotic experiences . A recent series of r and omized controlled intervention studies has shown that cognitive-behavioural approaches can improve sleep in people with psychotic experiences . However , the effects of psychological intervention for improving sleep have not been evaluated in young people at ultra-high risk of psychosis . Improving sleep might prevent later transition to a mental health disorder . Aims : To assess the feasibility and acceptability of an intervention targeting sleep disturbance in young people at ultra-high risk of psychosis . Method : Patients were sought from NHS mental health services . Twelve young people at ultra-high risk of psychosis with sleep problems were offered an eight-session adapted CBT intervention for sleep problems . The core treatment techniques were stimulus control , circadian realignment , and regulating day-time activity . Participants were assessed before and after treatment and at a one month follow-up . Results : All eligible patients referred to the study agreed to take part . Eleven patients completed the intervention , and one patient withdrew after two sessions . Of those who completed treatment , the attendance rate was 89 % and an average of 7.6 sessions ( SD = 0.5 ) were attended . There were large effect size improvements in sleep . Post-treatment , six patients fell below the recommended cut-off for clinical insomnia . There were also improvements in negative affect and psychotic experiences . Conclusion : This uncontrolled feasibility study indicates that treating  sleep problems in young people at ultra-high of psychosis is feasible , acceptable , and may be associated with clinical benefits ABSTRACT Blue wavelengths form the portion of the visible electromagnetic spectrum that most potently regulates circadian rhythm . We hypothesized that wearing blue-blocking ( BB ) glasses in the evening may influence circadian rhythm disturbances in patients with major depressive disorder ( MDD ) , result ing in improved sleep and mood . We used a r and omized placebo-controlled double-blinded design . Patients with MDD with sleep onset insomnia were r and omly assigned to wearing either BB glasses or clear glasses ( placebo ) . Patients were instructed to wear the glasses from 20:00 hours until bedtime for 2 weeks . We assessed sleep state ( sleep quality on a visual analog scale , the Morningness – Eveningness Question naire [ MEQ ] , and a sleep diary ) and depressive symptoms at baseline and after 2 weeks . Data were analyzed with a full analysis set . In total , 20 patients were r and omly assigned to the BB and placebo groups ( BB group , n = 10 ; placebo group , n = 10 ) . There were three dropouts ( BB group , n = 1 ; placebo group , n = 2 ) . At baseline , sleep quality , sleep latency ( assessed via a sleep diary ) , and antipsychotics use differed between the groups . To take account of these differences , the baseline sleep state or depressive symptoms and antipsychotics use were used as covariates in the later analysis . The change scores for sleep quality did not show a significant improvement in the BB group compared with the placebo group ( mean [ st and ard deviation , SD ] scores for BB versus placebo : 36.1 [ 31.7 ] versus 16.2 [ 15.1 ] , p = 0.43 ) , although half of the BB group showed a clear improvement in sleep quality . The change in MEQ scores did not significantly differ between the groups ( p = 0.14 ) , although there was a trend of a shift to morning type in the BB group ( 3.10 [ 4.95 ] points ) and to evening type in the placebo group ( 0.50 [ 3.89 ] points ) . There were no statistically significant changes in depressive symptoms in either group . Across both groups , 40 % of the participants reported pain or discomfort from wearing the glasses , which were available in only one size . Thus , the failure to find significant differences may have result ed from the glasses used in this study . Glasses fitted to individual patients may improve efficacy and safety . Replication of the study with a larger sample size and size-adjustable glasses is needed OBJECTIVES To improve nighttime sleep in nursing home patients . DESIGN Controlled clinical trial . SETTING Eight community nursing homes enrolled two at a time . PARTICIPANTS Of 1,077 patients assessed in the eight nursing homes , 638 ( 59 % ) were eligible , and consent was obtained for 273 ( 43 % of those eligible ) . Of the 230 who underwent baseline assessment s , 173 completed the immediate-intervention phase of the trial ( 77 in the intervention group and 96 in the control group ) . A total of 160 subjects completed the intervention ( 77 in the immediate-intervention group and 83 in the delayed-intervention phase ) . INTERVENTION Trained research staff provided the intervention , which included daytime physical activity and attempts to keep subjects out of bed , evening bright light exposure , a consistent bedtime routine , nighttime care routines design ed to minimize sleep disruption , and strategies to reduce nighttime noise . Subjects from one nursing home received the intervention ( Group 1 ) , whereas subjects in the second nursing home served as a control group ( Group 2 ) ; then Group 2 received the intervention . MEASUREMENTS Primary outcomes included measures of sleep recorded using wrist actigraphy in all subjects and polysomnography in a subgroup of subjects . Secondary measures included assessment s of mood and behavior using the Neuropsychiatric Inventory , the Geriatric Depression Scale , and behavioral observations . RESULTS There were no significant differences in any of the primary actigraphic sleep outcome measures between the intervention and control group after the immediate-intervention phase of the trial . In the 160 subjects who completed the intervention , there were no significant changes in any actigraphic measure of nighttime sleep , nor were there any significant changes in measures of sleep in the 45 subjects who had baseline and intervention polysomnography . CONCLUSION This multicomponent , nonpharmacological intervention conducted by trained research staff had no effect on nighttime sleep in this sample of nursing home patients . Enhanced nonpharmacological interventions should be developed and tested and combined with environmental interventions to mitigate noise when feasible . Adjunctive drug therapy may be needed to improve sleep in a substantial proportion of this population and should be tested in addition to nonpharmacological interventions in rigorous clinical trials Summary Background Sleep difficulties might be a contributory causal factor in the occurrence of mental health problems . If this is true , improving sleep should benefit psychological health . We aim ed to determine whether treating insomnia leads to a reduction in paranoia and hallucinations . Methods We did this single-blind , r and omised controlled trial ( OASIS ) at 26 UK universities . University students with insomnia were r and omly assigned ( 1:1 ) with simple r and omisation to receive digital cognitive behavioural therapy ( CBT ) for insomnia or usual care , and the research team were masked to the treatment . Online assessment s took place at weeks 0 , 3 , 10 ( end of therapy ) , and 22 . The primary outcome measures were for insomnia , paranoia , and hallucinatory experiences . We did intention-to-treat analyses . The trial is registered with the IS RCT N registry , number IS RCT N61272251 . Findings Between March 5 , 2015 , and Feb 17 , 2016 , we r and omly assigned 3755 participants to receive digital CBT for insomnia ( n=1891 ) or usual practice ( n=1864 ) . Compared with usual practice , the sleep intervention at 10 weeks reduced insomnia ( adjusted difference 4·78 , 95 % CI 4·29 to 5·26 , Cohen 's d=1·11 ; p<0·0001 ) , paranoia ( −2·22 , −2·98 to −1·45 , Cohen 's d=0·19 ; p<0·0001 ) , and hallucinations ( −1·58 , −1·98 to −1·18 , Cohen 's d=0·24 ; p<0·0001 ) . Insomnia was a mediator of change in paranoia and hallucinations . No adverse events were reported . Interpretation To our knowledge , this is the largest r and omised controlled trial of a psychological intervention for a mental health problem . It provides strong evidence that insomnia is a causal factor in the occurrence of psychotic experiences and other mental health problems . Whether the results generalise beyond a student population requires testing . The treatment of disrupted sleep might require a higher priority in mental health provision . Funding Wellcome Trust BACKGROUND Disturbances in rest-activity rhythm are prominent and disabling symptoms in Alzheimer 's disease ( AD ) . Nighttime sleep is severely fragmented and daytime activity is disrupted by multiple napping episodes . In most institutional environments , light levels are very low and may not be sufficient to enable the circadian clock to entrain to the 24-hour day . The purpose of this r and omized , placebo-controlled , clinical trial was to test the effectiveness of morning bright light therapy in reducing rest-activity ( circadian ) disruption in institutionalized patients with severe AD . METHOD Subjects ( n = 46 , mean age 84 years ) meeting the NINCDS-ADRDA ( National Institute of Neurological and Communicative Disorders and Stroke -- the Alzheimer 's Disease and Related Disorders Association ) AD diagnostic criteria were recruited from two large , skilled nursing facilities in San Francisco , California . The experimental group received one hour ( 09:30 - 10:30 ) of bright light exposure ( > or = 2500 lux in gaze direction ) Monday through Friday for 10 weeks . The control group received usual indoor light ( 150 - 200 lux ) . Nighttime sleep efficiency , sleep time , wake time and number of awakenings and daytime wake time were assessed using actigraphy . Circadian rhythm parameters were also determined from the actigraphic data using cosinor analysis and nonparametric techniques . Repeated measures analysis of variance ( ANOVA ) was used to test the primary study hypotheses . RESULTS AND CONCLUSION Although significant improvements were found in subjects with aberrant timing of their rest-activity rhythm , morning bright light exposure did not induce an overall improvement in measures of sleep or the rest-activity in all treated as compared to control subjects . The results indicate that only subjects with the most impaired rest-activity rhythm respond significantly and positively to a brief ( one hour ) light intervention Background Social rhythm refers to the regularity with which one engages in social activities throughout the week , and has established links with bipolar disorder , as well as some links with depression and anxiety . The aim of the present study is to examine social rhythm and its relationship to various aspects of health , including physical health , negative mental health , and positive mental health . Method Question naire data were obtained from a large-scale multi-national sample of 8095 representative participants from the U.S. , Russia , and Germany . Results Results indicated that  social rhythm irregularity  is related to increased reporting of health problems , depression , anxiety , and stress . In contrast , greater regularity is related to better overall health state , life satisfaction , and positive mental health . The effects are generally small in size , but hold even when controlling for gender , marital status , education , income , country , and social support . Further , social rhythm means differ across Russia , the U.S. , and Germany . Relationships with mental health are present in all three countries , but differ in magnitude . Conclusions  Social rhythm irregularity  is related to mental health in Russia , the U.S. , and Germany We treated delayed sleep phase syndrome ( DSPS ) with an illuminated mask that provides light through closed eyelids during sleep . Volunteers received either bright white light  ( 2,700 lux , n = 28 ) or dim red light placebo  ( 0.1 lux , n = 26 ) for 26 days at home . Mask lights were turned on ( < 0.01 lux ) 4 h before arising , ramped up for 1 h , and remained on at full brightness until arising . Volunteers also attempted to systematic ally advance sleep time , avoid naps , and avoid evening bright light . The light mask was well tolerated and produced little sleep disturbance . The acrophase of urinary 6-sulphatoxymelatonin ( 6-SMT ) excretion advanced significantly from baseline in the bright group ( p < 0.0006 ) and not in the dim group , but final phases were not significantly earlier in the bright group ( ANCOVA ns ) . Bright treatment did produce significantly earlier phases , however , among volunteers whose baseline 6-SMT acrophase was later than the median of 0602 h ( bright shift : 0732 - 0554 h , p < 0.0009 ; dim shift : 0746 - 0717 h , ns ; ANCOVA p = 0.03 ) . In this subgroup , sleep onset advanced significantly only with bright but not dim treatment ( sleep onset shift : bright 0306 - 0145 h , p < 0.0002 ; dim 0229 - 0211 h , ns ; ANCOVA p < .05 ) . Despite equal expectations at baseline , participants rated bright treatment as more effective than dim treatment ( p < 0.04 ) . We conclude that bright-light mask treatment advances circadian phase and provides clinical benefit in DSPS individuals whose initial circadian delay is relatively severe We investigated whether low intensity dawn-dusk simulation ( DDS ) , a ' naturalistic ' form of light therapy design ed to embed sleep in its accustomed phase , could improve the disturbed circadian rest-activity cycle , nocturnal sleep and and /or cognitive functions in dementia . A protocol of 3 weeks each of baseline , treatment and follow-up was completed by 13 patients ( 85yr old+/-5yr , MMSE 14+/-5 ; n=9 DDS versus n=4 ' placebo ' dim red light ) who wore an activity/lux monitor throughout . There were no significant changes 
    Output:
    
Although the small number of studies limited meta-regression , evening light avoidance was associated with greater increase in total sleep time .
Effects of light on sleep and circadian outcomes have received limited attention in studies in psychiatric disorders , but results were promising in these groups .