Baseline sleep quality moderates symptom improvement in veterans with comorbid PTSD and TBI receiving trauma-focused treatment.

Poor sleep quality is common among Veterans with posttraumatic stress disorder (PTSD) and history of traumatic brain injury (TBI). However, the relationship between sleep quality and treatment outcomes following trauma-focused interventions is less well-understood in this population. We sought to better understand whether 1) sleep quality changed as a result of trauma-focused treatment and 2) if baseline sleep quality moderated psychological and neurobehavioral treatment outcomes. Our sample consisted of 100 Iraq/Afghanistan era Veterans with PTSD and history of mild to moderate TBI who were randomized to one of two trauma-focused treatments: 1) Cognitive Processing Therapy (CPT) or 2) combined CPT and Cognitive Symptom Management and Rehabilitation Therapy (SMART-CPT). Self-reported sleep quality, psychiatric symptoms (PTSD and depression), and neurobehavioral concerns were assessed at multiple timepoints throughout the study. Multilevel modeling showed sleep quality did not improve, regardless of treatment condition. However, worse baseline sleep quality was associated with less improvement in PTSD symptoms and cognitive complaints. There was no effect of baseline sleep quality on change in depression symptoms. These findings suggest that more targeted treatments to address sleep quality either prior to or in conjunction with trauma-focused therapy may help to improve treatment outcomes for Veterans with comorbid PTSD and TBI history.

Psychometric Characteristics of the Insomnia Severity Index in Veterans With History of Traumatic Brain Injury.

OBJECTIVE/BACKGROUND: The Insomnia Severity Index (ISI) is a widely used self-report measure of insomnia symptoms. However, to date this measure has not been validated or well-characterized in veterans who have experienced traumatic brain injury (TBI). This study assessed the psychometric properties and convergent, divergent, construct, and discriminate validity of the ISI in veterans with a history of TBI. PARTICIPANTS: Eighty-three veterans with history of TBI were seen in the VA San Diego Healthcare System as part of a research protocol. METHODS: Measures included the ISI, Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale, Neurobehavioral Symptom Inventory, Beck Depression Inventory-II, Beck Anxiety Inventory, and PTSD Checklist-Military Version. RESULTS: The ISI demonstrated moderate to strong or excellent convergent and divergent validity. A principal component analysis indicated a single construct with excellent internal consistency (Cronbach's alpha = 0.92). In exploratory analyses, the ISI discriminated well between those with (73%) and without (27%) sleep disturbance based on the PSQI. CONCLUSIONS: Results from this study indicate validity of the ISI in assessing insomnia in veterans with history of TBI and suggest a cutoff score not dissimilar from non-TBI populations. Findings from this study can help inform clinical applicability of the ISI, as well as future studies of insomnia in TBI.

Early versus late wake therapy improves mood more in antepartum versus postpartum depression by differentially altering melatonin-sleep timing disturbances.

BACKGROUND: Peripartum major depression (MD) disables mothers and impairs emotional and neurocognitive development of offspring. We tested the hypothesis that critically-timed wake therapy (WT) relieves peripartum MD by altering melatonin and sleep timing, differentially, in antepartum vs. postpartum depressed patients (DP). METHODS: In a university clinical research center, we initially randomized 50 women - 26 antepartum (17 healthy comparison-HC, 9 DP) and 24 postpartum (8 HC, 16 DP) - to a cross-over trial of one night of early-night wake therapy (EWT: sleep 3:00-7:00 am) vs. late-night wake therapy (LWT: sleep 9:00 pm-01:00 am). Ultimately, we obtained mood, overnight plasma melatonin and polysomnography for: 15 antepartum women receiving EWT, 18 receiving LWT; 15 postpartum women receiving EWT, 14 receiving LWT. RESULTS: EWT improved mood more in antepartum vs. postpartum DP in conjunction with reduced (normalized) melatonin-sleep phase-angle differences (PADs) due to delayed melatonin onsets and advanced sleep onsets, and increased (from baseline) total sleep times (TST). LWT improved mood more in postpartum vs. antepartum DP in conjunction with increased TST. LIMITATIONS: Small samples potentially rendered the study underpowered to detect group differences, making confirmation with larger samples essential. Sufficient follow-up data were not available in most women to document the duration of the mood response to wake therapy. CONCLUSIONS: EWT benefitted antepartum DP more by realigning melatonin and sleep timing, whereas LWT benefitted postpartum DP more by increasing TST. Thus, consistent with precision medicine aims, maximum mood benefits accrue from timing sleep/wake interventions to specific peripartum circadian pathophysiologies.

Neurocognition, psychiatric symptoms, and lifetime homelessness among veterans with a history of traumatic brain injury.

We retrospectively investigated archival clinical data, including correlates of lifetime homelessness, in 503 Veterans with a history of traumatic brain injuries (86.5% mild) who completed neuropsychological evaluations and passed performance validity tests. The 471 never-homeless and 32 ever-homeless Veterans were compared on demographic factors, TBI severity, psychiatric diagnosis, subjective symptoms, and neuropsychological functioning. Homelessness history was significantly associated with unemployment, lower disability income, more severe depressive, anxiety, posttraumatic stress disorder, and postconcussive symptoms, and lower performances on two of fifteen neurocognitive tests. In a multiple logistic regression model, current unemployment and substance use disorder remained significantly associated with lifetime homelessness.

Correlates of employment and postsecondary education enrolment in Afghanistan and Iraq veterans with traumatic brain injuries.

PRIMARY OBJECTIVE: About 20% of Iraq and Afghanistan Veterans have sustained a traumatic brain injury (TBI), which can result in postconcussive symptoms and difficulty transitioning from the military to civilian employment and postsecondary education. To better inform programs help Veterans transition back into civilian life, we evaluated correlates of employment and postsecondary education enrolment among treatment-seeking Veterans with a history of TBI. RESEARCH DESIGN: A cross-sectional design, using an archival database of VA medical records, was used to answer these research questions. METHODS AND PROCEDURES: We examined demographic, TBI-related, postconcussive, psychiatric, and neuropsychological factors in 390 Veterans (86% with mild TBI) to determine what factors were associated with employment or enrolment in postsecondary education. Bivariate correlations and multivariate regression were used. MAIN OUTCOMES AND RESULTS: age, minority status, and service connected disability ratings were significantly associated with employment and postsecondary education enrolment in a multivariate context, whereas TBI-related factors and neurocognitive, postconcussive, and psychiatric symptom severity were not associated with employment or postsecondary education outcomes. CONCLUSIONS: Further research is needed to confirm these findings and to evaluate the contribution of age, minority status, and disability on successful return to work and/or school for Veterans with a history of TBI.

Postconcussive symptom overreporting in Iraq/Afghanistan Veterans with mild traumatic brain injury.

A comprehensive evaluation, including the assessment of neurobehavioral symptoms, has been instituted at the Department of Veterans Affairs (VA) healthcare system to address the large number of Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) Veterans returning with mild traumatic brain injuries (mTBIs). The Validity-10 is measure of symptom overreporting embedded within the Neurobehavioral Symptom Inventory, a component of the comprehensive evaluation that assesses postconcussive symptom severity. The Validity-10 is composed of 10 unlikely/low-frequency items and a validated cutoff score to identify postconcussive symptom overreporting. We examined the items and cutoff used in the initial development and validation study of the Validity-10 through retrospective chart reviews of 331 treatment-seeking Veterans who sustained an mTBI. The Validity-10 exhibited significant relationships with psychiatric variables, VA service connection, and neuropsychological performance validity (all p < 0.01), but nonsignificant relationships with demographic and injury variables (all p > 0.05). Furthermore, the Validity-10 modestly predicted neuropsychological performance validity test failure over and above psychiatric comorbidities and VA service connection. The present study supports the use of the Validity-10 to assess symptom validity in treatment-seeking OIF/OEF Veterans with a history of mTBI.

Multivariate assessment of subjective and objective measures of social and family satisfaction in Veterans with history of traumatic brain injury.

Approximately 20% of current-era Veterans have sustained a traumatic brain injury (TBI), which can result in persistent postconcussive symptoms. These symptoms may disrupt family and social functioning. We explored psychiatric, postconcussive, and cognitive factors as correlates of objective functioning and subjective satisfaction in family and social relationships. At entry into a supported employment study, 50 unemployed Veterans with a history of mild to moderate TBI and current cognitive impairment were administered baseline assessments. Multivariate stepwise regressions determined that higher levels of depressive symptomatology were strongly associated with less frequent social contact, as well as lower subjective satisfaction with family and social relationships. Worse verbal fluency predicted less frequent social contact, whereas worse processing speed and switching predicted higher levels of subjective satisfaction with family relationships. The pattern of results remained similar when examining those Veterans with only mild TBI. Depressive symptoms and cognitive functioning may impact Veterans' social contact and satisfaction with family and social relationships. Evidence-based interventions addressing depression and cognition may therefore aid in improving community reintegration and satisfaction with social and family relationships.

Neuropsychological performance in treatment-seeking Operation Enduring Freedom/Operation Iraqi Freedom Veterans with a history of mild traumatic brain injury.

INTRODUCTION: Clinical neuropsychological presentation of treatment-seeking Veterans with a remote history of mild traumatic brain injury (mTBI) is widely variable. This manuscript seeks to better characterize cognitive concerns in the post-acute phase following mTBI and to identify the neuropsychological profiles of a large sample of clinically referred Operation Enduring Freedom/Operation Iraqi Freedom/Operation New Dawn (OEF/OIF/OND) Veterans with a history of mTBI and current cognitive complaints. We hypothesized that a minority of cases would exhibit valid and widespread neuropsychological deficits. METHOD: Retrospective chart reviews of neuropsychological testing and mental health symptoms and diagnoses were conducted on 411 clinically referred OEF/OIF/OND Veterans with a history of mTBI. Groups were created based on scores on performance validity measures and based on overall neuropsychological performance. RESULTS: A total of 29.9% of the sample performed below normative expectations on at least one performance validity test (PVT). Of those Veterans performing adequately on PVTs, 60% performed within normal limits on virtually all neuropsychological measures administered, leaving only 40% performing below expectations on two or more measures. Mood and neurobehavioral symptoms were significantly elevated in Veterans performing below cutoff on PVTs compared to Veterans who performed within normative expectations or those with valid deficits. Neurobehavioral symptoms were significantly correlated with mental health symptom reports but not with injury variables. CONCLUSIONS: In summary, in a large sample of clinically referred Veterans with persistent cognitive complaints after mild TBI, a third demonstrated invalid clinical neuropsychological testing, and, of those performing at or above cutoff on PVTs, over half performed within normative expectations across most neuropsychological tests administered. Results highlight the importance of objective assessment of cognitive functioning in this population as subjective reports do not correspond to objective assessment in the majority of cases.

A quantitative review of cognitive functioning in homeless adults.

Homeless people experience elevated rates of risk factors for cognitive impairment. We reviewed available peer-reviewed studies reporting data from objective measures of cognition in samples identified as homeless. Pooled sample-weighted estimates of global cognitive screening measures, full-scale intelligence quotient (IQ), and premorbid IQ were calculated, in addition to pooled sample characteristics, to understand the representativeness of available studies. A total of 24 unique studies were identified, with 2969 subjects. The pooled estimate for the frequency of cognitive impairment was 25%, and the mean full-scale IQ score was 85, 1 standard deviation below the mean of the normal population. Cognitive impairment was found to be common among homeless adults and may be a transdiagnostic problem that impedes rehabilitative efforts in this population. Comparatively little data are available about cognition in homeless women and unsheltered persons.

The Relationship Between Postconcussive Symptoms and Quality of Life in Veterans With Mild to Moderate Traumatic Brain Injury.

OBJECTIVE: To assess the relationship between postconcussive symptoms and quality of life (QOL) in Veterans with mild to moderate traumatic brain injury (TBI). METHODS: Sixty-one Operation Enduring Freedom/Operation Iraqi Freedom/Persian Gulf War Veterans with a history of mild or moderate TBI, more than 6 months postinjury, and 21 demographically matched Veteran controls were administered self-report measures of QOL (World Health Organization Quality of Life-BREF) and postconcussive symptom severity (Neurobehavioral Symptom Inventory). RESULTS: Perceived QOL was significantly worse in Veterans with mild-moderate TBI than in controls. In the TBI group, QOL was predominantly associated with affective symptoms, and moderate to strong correlations with fatigue and depression were evident across all QOL areas. Multivariate analyses revealed depression and fatigue to be the best predictors of Psychological, Social, and Environmental QOL, whereas sleep difficulty best predicted Physical QOL in mild-moderate TBI. CONCLUSION: Veterans with post-acute mild-moderate TBI evidence worse QOL than demographically matched Veteran controls. Affective symptoms, and specifically those of fatigue, depression, and sleep difficulty, appear to be the most relevant postconcussive symptoms predicting QOL in this population. These findings underscore the importance of examining specific symptoms as they relate to post-acute TBI QOL and provide guidance for treatment and intervention studies.

Validation of the Modified Fatigue Impact Scale in mild to moderate traumatic brain injury.

OBJECTIVE: To evaluate the validity of the Modified Fatigue Impact Scale (MFIS) in veterans with a history of mild to moderate traumatic brain injury (TBI). PARTICIPANTS: Veterans (N = 106) with mild (92%) or moderate (8%) TBI. SETTING: Veterans Administration Health System. PROCEDURE: Factor structure, internal consistency, convergent validity, sensitivity, and specificity of the MFIS were examined. RESULTS: Principal component analysis identified 2 viable MFIS factors: a Cognitive subscale and a Physical/Activities subscale. Item analysis revealed high internal consistency of the MFIS Total scale and subscale items. Strong convergent validity of the MFIS scales was established with 2 Beck Depression Inventory II fatigue items. Receiver operating characteristic curve analysis revealed good to excellent accuracy of the MFIS in classifying fatigued versus nonfatigued individuals. CONCLUSION: The MFIS is a valid multidimensional measure that can be used to evaluate the impact of fatigue on cognitive and physical functioning in individuals with mild to moderate TBI. The psychometric properties of the MFIS make it useful for evaluating fatigue and provide the potential for improving research on fatigue in this population.

Subjective sleepiness and daytime functioning in bariatric patients with obstructive sleep apnea.

PURPOSE: The purpose of this study was to evaluate associations between obstructive sleep apnea (OSA) severity and self-reported sleepiness and daytime functioning in patients considering bariatric surgery for treatment of obesity. METHODS: Using a retrospective cohort design, we identified 342 patients who had sleep evaluations prior to bariatric surgery. Our final sample included 269 patients (78.6 % of the original cohort, 239 females; mean age = 42.0 ± 9.5 years; body mass index = 50.2 ± 7.7 kg/m(2)) who had overnight polysomnography and completed the Epworth Sleepiness Scale (ESS) and the Functional Outcomes of Sleep Questionnaire (FOSQ). Patients' OSA was classified as none/mild (apnea-hypopnea index (AHI) < 15, n = 112), moderate (15 ≤ AHI < 30, n = 77), or severe (AHI ≥ 30, n = 80). We calculated the proportion of unique variance (PUV) for the five FOSQ subscales. ANOVA was used to determine if ESS and FOSQ were associated with OSA severity. Unpaired t tests compared ESS and FOSQ scores in our sample with published data. RESULTS: The average AHI was 29.5 ± 31.5 events per hour (range = 0-175.8). The mean ESS score was 6.3 ± 4.8, and the mean global FOSQ score was 100.3 ± 18.2. PUVs for FOSQ subscales showed moderate-to-high unique contributions to FOSQ variance. ESS and global FOSQ score did not differ by AHI group. Only the FOSQ vigilance subscale differed by OSA severity with the severe group reporting more impairment than the moderate and none/mild groups. Our sample reported less sleepiness and daytime impairment than previously reported means in patients and controls. CONCLUSIONS: Subjective sleepiness and functional impairment were not associated significantly with OSA severity in our sample of patients considering surgery for obesity. Further research is needed to understand individual differences in sleepiness in patients with OSA. If bariatric patients underreport symptoms, self-report measures are not an adequate substitute for objective assessment and clinical judgment when evaluating bariatric patients for OSA. Patients with severe obesity need evaluation for OSA even in the absence of subjective complaints.

Polysomnographic evaluation of sleep quality and quantitative variables in women as a function of mood, reproductive status, and age.

This archival cross-sectional investigation examined the impact of mood, reproductive status (RS), and age on polysomnographic (PSG) measures in women. PSG was performed on 73 normal controls (NC) and 64 depressed patients (DP), in the course of studies in menstruating, pregnant, postpartum, and peri- and postmenopausal women. A two-factor, between-subjects multivariate analysis of variance (MANOVA) was used to test the main effects of reproductive status (RS: menstrual vs pregnant vs postpartum vs menopausal) and diagnosis (NC vs DP), and their interaction, on PSG measures. To further refine the analyses, a two-factor, between subjects MANOVA was used to test the main effects of age (19 to 27 vs 28 to 36 vs 37 to 45 vs 46+ years) and diagnosis on the PSG data. Analyses revealed that in DP women, rapid eye movement (REM) sleep percentage was significantly elevated relative to NC across both RS and age. Significant differences in sleep efficiency, Stage 1%, and REM density were associated with RS; differences in total sleep time, Stage 2 percentage, and Stage 4 percentage were associated with differences in age. Both RS and age were related to differences in sleep latency, Stage 3 percentage, and Delta percentage. Finally, wake after sleep onset time, REM percentage, and REM latency did not vary with respect to RS or age. Overall, this investigation examined three major variables (mood, RS, and age) that are known to impact sleep in women. Of the variables, age appeared to have the greatest impact on PSG sleep measures, reflecting changes occurring across the lifespan.

Esta investigación evaluó el impacto del ánimo, del estado reproductive (ER) y de la edad en las mediciones polisomnográficas (PSG) de registros de corte transversal en mujeres. Las mediciones PSG se realizaron en 73 controles normales (CN) y 66 pacientes con depresión (PD), en estudios durante la etapa menstrual, el embarazo, el postparto y, la peri y postmenopausia. Para evaluar los principales efectos del estado reproductivo (ER: menstrual v/s embarazo v/s postparto v/s menopausia) y del diagnóstico (CN v/s PD) en la interacción con las mediciones PSG se utilizó un análisis de la varianza multivariado (MANOVA) entre sujetos, para dos factores. Para perfeccionar aun más los análisis en la evaluación de los principales efectos de la edad (19 a 27 v/s 28 a 36 v/s 37 a 45 v/s 46 y más años) y del diagnóstico respecto a los datos PSG se empleó MANOVA entre sujetos, para dos factores. Los análisis revelaron que en las mujeres con depresión el porcentaje de sueño de movimientos oculares rápidos (REM) fue significativamente mayor en relación a los CN tanto para ER como para edad. Hubo diferencias significativas para la eficiencia del sueño, el porcentaje de la etapa 1 y la densidad del sueño REM que se asociaron con el ER. Diferencias para el tiempo total de sueño y el porcentaje de las etapas 2 y 4 se asociaron con diferencias en la edad. Tanto el ER como la edad se relacionaron con diferencias en la latencia de sueño, el porcentaje de la etapa 3 y el porcentaje de delta. Por último, el tiempo para despertar después de iniciar el sueño, el porcentaje de sueno REM y la latencia REM no variaron con relación al ER ni a la edad. Esta investigación examinó globalmente tres importantes variables (ánimo, ER y edad) que se sabe que influyen en el sueño en la mujer. De estas variables la edad tuvo el mayor impacto en las mediciones PSG del sueño, reflejando los cambios que ocurren a lo largo de la vida.

Cette étude croisée d'archives a analysé l'impact de l'humeur, de l'état reproducteur (ER) et de l'âge sur les mesures polysomnographiques (PSG) des femmes. Des mesures PSG ont été réalisées sur 73 patientes témoins normales (TN) et 64 patientes déprimées (PD), au cours d'études chez des femmes ayant leurs règles, enceintes, pendant le postpartum, en périménopause ou déjà ménopausées. Une analyse de variance multivariée (MANOVA) à deux facteurs intersujets a testé les principaux effets de l'état reproducteur (ER: femmes ayant leurs règles vs enceintes vs pendant le postpartum vs ménopausées), du diagnostic (TN vs PD), et leur interaction sur les mesures PSG. Pour affiner ultérieurement les résultats, une analyse MANOVA à deux facteurs intersujets a été utilisée pour tester les principaux effets de l'âge (19 à 27 vs 28 à 36 vs 37 à 45 vs + de 46 ans) et du diagnostic sur les données PSG. Les analyses ont montré que chez les PD, le pourcentage de sommeil à mouvements oculaires rapides (REM) ou sommeil paradoxal était significativement élevé par rapport aux TN, à ER et âge équivalents. L'ER était associé à des différences significatives de fonctionnement du sommeil, de pourcentage de sommeil de stade 1 et de densité de sommeil REM ; avec l'âge, la durée totale du sommeil et le pourcentage de sommeil des stades 2 et 4 étaient changé. L'ER et l'âge ont influé sur la latence du sommeil, le pourcentage de sommeil de stade 3 et le delta. Finalement, l'ER ou l'âge n'ont rien changé au réveil après l'installation du sommeil, au pourcentage et à la latence de sommeil REM. Cette étude a analysé globalement trois variables principales (humour, ER et âge) connues pour influer sur le sommeil chez les femmes. Parmi les variables, l'âge semble avoir le plus grand impact sur les mesures PSG du sommeil, reflétant les changements intervenant au cours de la vie.

Traumatic brain injury and sleep disturbance: a review of current research.

OBJECTIVE: To summarize the current literature regarding the significant prevalence and potential consequences of sleep disturbance following traumatic brain injury (TBI), particularly mild TBI. DESIGN: PubMed and Ovid/MEDLINE databases were searched by using key words "sleep disturbance," "insomnia," "TBI," "brain injury," and "circadian rhythms." Additional sources (eg, abstracts from the annual Associated Professional Sleep Societies meeting) were also reviewed. RESULTS: Sequelae of TBI include both medical and psychiatric symptoms and frequent complaints of sleep disturbance. Sleep disturbance likely result from and contribute to multiple factors associated with the injury, all of which complicate recovery and resolution of symptoms. Interestingly, research now seems to indicate that mild TBI may be more correlated with increased likelihood of sleep disturbance than are severe forms of TBI. CONCLUSIONS: Sleep disturbance is a common consequence of TBI, but much more research is required to elucidate the nature and extent of this relation. Research needs to focus on (1) uncovering the specific types, causes, and severity of TBI that most often lead to sleep problems; (2) the specific consequences of sleep disturbance in this population (eg, impaired physical or cognitive recovery); and (3) the most effective strategies for the treatment of sleep-wake abnormalities in this population.

Discrepancy between subjective symptomatology and objective neuropsychological performance in insomnia.

STUDY OBJECTIVES: While daytime impairment is a defining feature of primary insomnia (PI), prior research using objective measures has not yielded clear and reliable evidence of global or specific deficits. In this investigation subjective and neuropsychological measures of daytime impairment were concurrently evaluated in subjects with primary insomnia (PIs) and in healthy good sleeper subjects (GSs). The goals for the study were to assess (1) whether PIs differ from GSs on subjective and/or objective measures and (2) the extent to which subjective and objective measures provide discordant information. DESIGN: Subjects were evaluated on multiple self-report measures of sleep and daytime performance and were administered a comprehensive set of neuropsychological tests. SETTING: The University of Rochester Sleep and Neurophysiology Research Laboratory (Rochester, NY). PATIENTS OR PARTICIPANTS: Forty-nine subjects (32 PIs and 17 GSs). Seventy-one percent of the sample was female; average age 39 +/- 11 yrs. RESULTS: Overall, PIs reported worse sleep, diminished activity levels, and a greater number and severity of daytime complaints. However, PIs did not show deficits on neuropsychological tests. Additionally, neuropsychological measures were not associated with severity of daytime complaints. Objectively measured sleep was found to be associated with performance (motor speed), while prospective and objective sleep measures were associated with level of daytime complaint. CONCLUSIONS: The discrepancy between subjective daytime complaints and objective performance in individuals with insomnia is common, but poorly understood. This discordance may suggest that daytime impairment corresponds less to "output" and more to attentional bias or to the realistic appraisal that "effort" is required to maintain normal performance.

The effects of one night of sleep deprivation on known-risk and ambiguous-risk decisions.

Sleep deprivation has been shown to alter decision-making abilities. The majority of research has utilized fairly complex tasks with the goal of emulating 'real-life' scenarios. Here, we use a Lottery Choice Task (LCT) which assesses risk and ambiguity preference for both decisions involving potential gains and those involving potential losses. We hypothesized that one night of sleep deprivation would make subjects more risk seeking in both gains and losses. Both a control group and an experimental group took the LCT on two consecutive days, with an intervening night of either sleep or sleep deprivation. The control group demonstrated that there was no effect of repeated administration of the LCT. For the experimental group, results showed significant interactions of night (normal sleep versus total sleep deprivation, TSD) by frame (gains versus losses), which demonstrate that following as little as 23 h of TSD, the prototypical response to decisions involving risk is altered. Following TSD, subjects were willing to take more risk than they ordinarily would when they were considering a gain, but less risk than they ordinarily would when they were considering a loss. For ambiguity preferences, there seems to be no direct effect of TSD. These findings suggest that, overall, risk preference is moderated by TSD, but whether an individual is willing to take more or less risk than when well-rested depends on whether the decision is framed in terms of gains or losses.

Compensatory recruitment after sleep deprivation and the relationship with performance.

This study examined the effects of total sleep deprivation (TSD) on cerebral responses to a verbal learning task with two levels of word difficulty. A total of 32 subjects were studied with functional magnetic resonance imaging (FMRI) after normal sleep and following 36 h of TSD. Cerebral responses to EASY words were identical on both nights, but several brain regions showed increased activation to HARD words following TSD compared with following a normal night of sleep (NORM). These regions included bilateral inferior frontal gyrus, bilateral dorsolateral prefrontal cortex, and bilateral inferior parietal lobe. Better free recall performance on the HARD words after TSD was related to increased cerebral responses within the left inferior and superior parietal lobes and left inferior frontal gyrus. Recall was negatively related to activation within the right inferior frontal gyrus. Overall, the findings support the predictions of the compensatory recruitment hypothesis that task demands influence both the likelihood and location of increased cerebral activation during task performance following TSD, and refine that hypothesis by identifying a specific task demand that plays a role. The performance relationships suggest increased activation may be both beneficial (compensatory) and interfere with task performance, depending on the brain regions involved.

Functional imaging of the sleeping brain: review of findings and implications for the study of insomnia.

Despite the growing literature indicating that insomnia is prevalent and a substantial risk factor for medical and psychiatric morbidity, the pathophysiology of both Primary and Secondary Insomnia is poorly understood. Multiple trait and state factors are thought to give rise to and/or moderate illness severity in insomnia, but 'hyperarousal' is widely believed to be the final common pathway of the disorder. To date, very little work has been undertaken using functional imaging to explore the CNS correlates, underpinnings, or consequences of hyperarousal as it occurs in Primary Insomnia. In fact, all but one of the extant studies have been of healthy good sleepers or subjects with Secondary Insomnia. In the present article, we: (1) review the studies that have been undertaken in good sleepers and in patients using functional neuroimaging methodologies, and (2) discuss how these data can inform a research agenda aimed at describing the neuropathophysiology of insomnia.

No association of sleep with total daily physical activity in normal sleepers.

The aim of two studies was to examine both between-subjects and within-subjects associations between daily amounts of physical activity and sleep in the home environment. Study 1 examined self-reported exercise durations and sleep diaries for 105 consecutive days in 31 college students who were normal sleepers. Between-subjects associations of mean exercise with mean sleep were assessed with Spearman rank-order correlations. Within-subjects correlations were determined across 105 days, and by comparing sleep on the 11 most active vs. the 11 least active days. Study 2 examined 71 physically active adults (n=38 ages 18-30 years, and n=33 ages 60-75 years), the majority of whom were normal sleepers. Over seven consecutive days, physical activity was assessed via actigraphy and a diary-derived estimate of energy expenditure, and sleep was assessed via actigraphy and sleep diaries. Between-subjects associations of mean physical activity with mean sleep were assessed with partial correlations, controlling for age. Within-subjects associations were assessed with ANCOVAs, with daily physical activity serving as the covariate, and by comparing sleep on the most active vs. the least active day. No significant within-subjects associations between physical activity and sleep were found in the main analyses of either study. Two small, but significant, between-subjects correlations between different physical activity measures and subjective sleep were found in Study 2. These results fail to support epidemiologic data on the value of exercise for sleep, but are consistent with experimental evidence showing only modest effects of exercise on sleep.

The effects of an orally administered cholinergic agonist on REM sleep in major depression.

BACKGROUND: Centrally active cholinergic agents such as arecoline and physostigmine shorten rapid eye movement (REM) latency, reduce REM interval times, or both and do so preferentially in patients with depression. We tested an orally administered cholinergic agonist (donepezil HCL 10 mg [Aricept]) to determine whether this agent also alters REM timing in depressed patients (n = 8) compared with age- and gender-matched control subjects (n = 8). METHODS: All subjects were studied for 3 consecutive nights in the sleep laboratory. The design was a fixed-order placebo-donepezil protocol to accommodate the long half-life of donepezil. Night 1 served as an adaptation night. On night 2, placebo was administered at 8:00 PM. On night 3, donepezil was administered at 8:00 PM. RESULTS: The cholinergic challenge distinguished the groups. In depressed patients REM latency was reduced compared with baseline (47.6 vs. 64.4, p =.04) following administration of donepezil. Control subjects showed no response: REM latency after donepezil was virtually identical to baseline REM latency (71.7 vs. 69.3). CONCLUSIONS: These data indicate that donepezil is likely to be useful in testing hypotheses related to cholinergic function in mood disorders.