[Changes in the routine work and moral distress in psychiatric care during the COVID-19 pandemic : A survey among physicians active in inpatient care in Germany]. / Änderungen des Arbeitsalltags und Moral Distress in der psychiatrischen Versorgung während der COVID-19-Pandemie : Eine Umfrage unter stationär tätigen Ärzt*innen in Deutschland.

BACKGROUND: During the COVID-19 pandemic a number of ethical challenges have arisen in the healthcare system. A psychological response to moral challenges is termed moral distress (MD). OBJECTIVE: Identification of causes of MD in inpatient psychiatric care in the context of the COVID-19 pandemic in Germany. MATERIAL AND METHODS: A survey was conducted using a self-administered non-validated online questionnaire as part of a cross-sectional study, in which 26 items about the experience of MD were examined and open questions about the handling of the pandemic and its effects on everyday work were posed. Physicians who worked in inpatient psychiatric care during the COVID-19 pandemic in Germany were surveyed anonymously with a convenience sample. The data acquisition took place between 17 November 2020 and 6 May 2021. RESULTS: A total of 141 participants were included. They indicated multiple pandemic-related changes in their daily work partly resulting in MD. CONCLUSION: MD is a neglected potential burden of inpatient psychiatric care under pandemic conditions (and beyond), which requires further research and an adequate handling. These results include implications for decision makers in crisis teams as well as a need for support services such as clinical ethics consultation services.

Sleep recordings in individuals with borderline personality disorder before and after trauma therapy.

Most individuals diagnosed with borderline personality disorder (BPD) have been exposed to severe and traumatic stressors and thus frequently present with symptoms of a posttraumatic stress disorder (PTSD). Severe sleep disturbances often accompany these complex cases, but changes of sleep parameters during therapy and the impact of sleep on treatment response have barely been studied. Narrative Exposure Therapy (NET) is an evidence-based approach for the treatment of trauma-related psychological disorders. To investigate the effect of NET on sleep in patients with BPD and comorbid PTSD, we screened 45 inpatients and outpatients who met the inclusion criteria of both diagnoses according to DSM-IV and who had a minimum of 2 weeks' stable medication. Patients were allocated to NET (N = 13) or treatment as usual (TAU; N = 8) in blocks. Polysomnographies and psychological questionares were performed before, directly and 6 months after the last therapy session. The aim of this pilot study was to investigate the effectiveness of trauma therapy by NET on sleep quantity (total sleep time) and sleep continuity (sleep efficiency and awakenings) in patients with comorbid BPD and PTSD. Participants of the NET group compared with those who received TAU showed an increased reduction in sleep latency from baseline to the end of therapy and a reduction in arousals over time. Patients with longer pre-treatment total sleep time and pre-treatment REM sleep duration showed a better outcome of NET with respect to PTSD symptoms. NET seems not lead to a change in sleep for the worse during therapy and seems to improve sleep as good as treatment as usual. Furthermore, our results provide evidence of an influence of sleep structure at baseline on treatment success later on.

Sleep enhances memory consolidation in the hippocampus-dependent object-place recognition task in rats.

The positive impact of sleep on memory consolidation has been shown for human subjects in numerous studies, but there is still sparse knowledge on this topic in rats, one of the most prominent model species in neuroscience research. Here, we examined the role of sleep in the object-place recognition task, a task closely comparable to tasks typically applied for testing human declarative memory: It is a one-trial task, hippocampus-dependent, not stressful and can be repeated within the same animal. A test session consisted of the Sample trial, followed by a 2-h retention interval and a Test trial, the latter examining the memory the rat had for the places of two objects presented at the Sample trial. In Experiment 1, each rat was tested twice, with the retention interval taking place either in the morning or evening, i.e., in the inactive or active phase, respectively. Rats showed significantly (p<0.01) better memory for object place after the Morning session. To control for confounding circadian factors, in Experiment 2 rats were tested four times, i.e., in the morning or in the evening while sleep was or was not deprived. Sleep during the retention interval was recorded polysomnographically. Rats only showed significant memory for the target object place in the Test trial after the Morning retention interval in the absence of sleep deprivation, and recognition performance in this condition was significantly superior to that in the three other conditions (p<0.05). EEG recordings during spontaneous morning sleep revealed increased slow oscillation (0.85-2.0 Hz) and upper delta (2.0-4.0 Hz), but reduced spindle band (10.5-13.5 Hz) activity, as compared to evening sleep. However, spindle band power was increased in the Morning retention interval in comparison to a Morning Baseline period (p<0.05). We conclude that consolidation of object-place memory depends on sleep, and presumably requires NonREM sleep rich in both slow wave and spindle activity.

Declarative memory performance is associated with the number of sleep spindles in elderly women.

OBJECTIVE: Recent evidence suggests that the sleep-dependent consolidation of declarative memory relies on the nonrapid eye movement rather than the rapid eye movement phase of sleep. In addition, it is known that aging is accompanied by changes in sleep and memory processes. Hence, the purpose of this study was to investigate the overnight consolidation of declarative memory in healthy elderly women. SETTING: Sleep laboratory of University. PARTICIPANTS: Nineteen healthy elderly women (age range: 61-74 years). MEASUREMENTS: We used laboratory-based measures of sleep. To test declarative memory, the Rey-Osterrieth Complex Figure Test was performed. RESULTS: Declarative memory performance in elderly women was associated with Stage 2 sleep spindle density. Women characterized by high memory performance exhibited significantly higher numbers of sleep spindles and higher spindle density compared with women with generally low memory performance. CONCLUSION: The data strongly support theories suggesting a link between sleep spindle activity and declarative memory consolidation.

Bed-Sharing in Couples Is Associated With Increased and Stabilized REM Sleep and Sleep-Stage Synchronization.

BACKGROUND/OBJECTIVES: Sharing the bed with a partner is common among adults and impacts sleep quality with potential implications for mental health. However, hitherto findings are contradictory and particularly polysomnographic data on co-sleeping couples are extremely rare. The present study aimed to investigate the effects of a bed partner's presence on individual and dyadic sleep neurophysiology. METHODS: Young healthy heterosexual couples underwent sleep-lab-based polysomnography of two sleeping arrangements: individual sleep and co-sleep. Individual and dyadic sleep parameters (i.e., synchronization of sleep stages) were collected. The latter were assessed using cross-recurrence quantification analysis. Additionally, subjective sleep quality, relationship characteristics, and chronotype were monitored. Data were analyzed comparing co-sleep vs. individual sleep. Interaction effects of the sleeping arrangement with gender, chronotype, or relationship characteristics were moreover tested. RESULTS: As compared to sleeping individually, co-sleeping was associated with about 10% more REM sleep, less fragmented REM sleep (p = 0.008), longer undisturbed REM fragments (p = 0.0006), and more limb movements (p = 0.007). None of the other sleep stages was significantly altered. Social support interacted with sleeping arrangement in a way that individuals with suboptimal social support showed the biggest impact of the sleeping arrangement on REM sleep. Sleep architectures were more synchronized between partners during co-sleep (p = 0.005) even if wake phases were excluded (p = 0.022). Moreover, sleep architectures are significantly coupled across a lag of ± 5min. Depth of relationship represented an additional significant main effect regarding synchronization, reflecting a positive association between the two. Neither REM sleep nor synchronization was influenced by gender, chronotype, or other relationship characteristics. CONCLUSION: Depending on the sleeping arrangement, couple's sleep architecture and synchronization show alterations that are modified by relationship characteristics. We discuss that these alterations could be part of a self-enhancing feedback loop of REM sleep and sociality and a mechanism through which sociality prevents mental illness.

Olfactory dysfunction in patients with narcolepsy with cataplexy is restored by intranasal Orexin A (Hypocretin-1).

Until recently, olfactory dysfunction was an unknown feature of narcolepsy. Orexin A, also called hypocretin-1, is abnormally decreased or undetectable in the cerebrospinal fluid of narcoleptic patients with cataplexies. As hypothalamic orexin-containing neurons project throughout the entire olfactory pathway, from the olfactory mucosa to the olfactory cortex, disturbed orexinergic transmission may crucially be involved in impaired olfactory performance of narcolepsy patients. In our study we analysed the olfactory performance (threshold, discrimination, identification and sum score of these measurements, the TDI score) of narcoleptic patients with cataplexies (n = 10) and of age-, gender-, BMI- and smoker/non-smoker-matched healthy controls (n = 10). We then in a double-blind, randomized, placebo-controlled cross-over design applied orexin A intranasally to seven of the patients and measured 2-phenyl-ethyl alcohol (PEA) single-staircase odour detection thresholds. Compared to the controls, patients showed significantly lower scores for olfactory threshold (patients: median 8.0, range 4.0-10.5; controls: median 9.4, range 7.5-13.3; P < 0.05), discrimination (patients: median 12.5, range 10-15; controls: median 15.0, range 12-16; P < 0.005), identification (patients: median 13.0, range 10-16; controls: median 14.0, range 13-16; P < 0.05) and TDI score (patients: median 33.4, range 30-36; controls: median 38.4, range 35-43; P < 0.0001). In all patients, the PEA olfactory threshold score increased after administration of orexin A (median 11.5, range 6.5-13.25) compared to placebo (median 7.75, range 6.25-11.25; P < 0.05). Our results support the hypothesis that mild olfactory dysfunction is an intrinsic symptom of narcolepsy with cataplexies. The observation that intranasal orexin A restores olfactory function is in favour of this hypothesis. Furthermore, our data support that the pathophysiological mechanism underlying olfactory dysfunction in narcolepsy is the lack of CNS orexin.

Relationship between cerebrospinal fluid concentrations of orexin A/hypocretin-1 and body composition in humans.

The hypothalamic neuropeptide orexin A (hypocretin-1) is a key signal in sleep/wake regulation and promotes food intake. We investigated the relationship between cerebrospinal fluid orexin A concentrations and body composition in non-narcoleptic human subjects with a wide range of body weight to gain insight into the role of orexin A in human metabolism. We collected cerebrospinal fluid and blood samples and measured body composition by bioelectric impedance analysis in 36 subjects (16 women and 20 men) with body mass indices between 16.24 and 38.10 kg/m2 and an age range of 19-80 years. Bivariate Pearson correlations and stepwise multiple regressions were calculated to determine associations between orexin A and body composition as well as biometric variables. Concentrations of orexin A in cerebrospinal fluid averaged 315.6 ±â€¯6.0 pg/ml, were comparable between sexes (p > 0.15) and unrelated to age (p > 0.66); they appeared slightly reduced in overweight/obese compared to normal-weight subjects (p = .07). Orexin A concentrations decreased with body weight (r = -0.38, p = .0229) and fat-free mass (r = -0.39, p = .0173) but were not linked to body fat mass (p > 0.24). They were inversely related to total body water (r = -0.39, p = .0174) as well as intracellular (r = -0.41, p = .0139) and extracellular water (r = -0.35, p = .0341). Intracellular water was the only factor independently associated with cerebrospinal fluid orexin A concentrations (p = .0139). We conclude that cerebrospinal fluid orexin A concentrations do not display associations with body adiposity, but are inversely related to intracellular water content. These cross-sectional findings suggest a link between orexin A signaling and the regulation of water homeostasis in humans.

Slow-wave sleep predicts long-term social functioning in severe mental illness.

Sleep's relevance for long-term social functioning in psychiatric disorders has been widely overlooked so far. Here, we investigate social functioning in a transdiagnostic sample of 31 patients with severe mental illness, namely schizophrenia (n = 15) or major depression (n = 16), in relation to their polysomnographic sleep characteristics 6 (± 2.4) years earlier. In addition, cognitive performance at follow-up and clinical characteristics (i.e., severity of disorder-related symptoms and number of hospitalizations between baseline and follow-up) are assessed. Multiple regression analysis results in a model with slow-wave sleep (SWS) and number of hospitalizations as significant predictors accounting for 50% (R2 = 0.507; p <0.001) of the variance in social functioning. SWS remains a significant predictor of long-term social functioning throughout a series of refining analyses which also identify baseline functioning as an additional significant predictor, whereas diagnosis is non-significant. Also, the effect of SWS on social functioning is not mediated by number of hospitalizations as assessed by a bootstrapped mediation analysis. We thus conclude that duration of slow-wave sleep is a powerful predictor of long-term social outcome in psychiatric disorders. Also, we discuss the relevance of verbal memory, symptom severity, and diagnostic category for social functioning. Future studies should test this finding by using a prospective design, a bigger sample, optimized predictor variables, and a more diverse set of diagnoses. Moreover, it should be explored whether or not treating sleep disturbances in psychiatric illnesses independently improves long-term social functioning.

Association of daytime sleepiness with nigrostriatal dopaminergic degeneration in early Parkinson's disease.

INTRODUCTION: Many patients with Parkinson's disease (PD) report daytime sleepiness. Its etiology, however, is still not fully understood. The aim of this study was to examine if the amount of nigrostriatal dopaminergic degeneration is associated with subjective daytime sleepiness in patients with PD. PATIENTS AND METHODS: We investigated 21 patients with PD clinically and by means of [(123)I] FP-CIT-SPECT (DaTSCAN(R)). Each patient filled in the Epworth sleepiness scale (ESS), the Parkinson's Disease Sleep Scale (PDSS), and the self-rating depression scale according to Zung (SDS) to assess sleepiness, sleep quality, and depressive symptoms. RESULTS: The mean specific dopamine transporter binding in the 21 PD patients (60.8 +/- 10.4 years, nine females, median Hoehn and Yahr stage 2.0) was decreased. Nine patients were in Hoehn and Yahr stage 1 (58.7 +/- 6.6 years, four females; ESS score 7.4 +/- 4.5; PDSS score 105.1 +/- 30.9), the other 12 patients were in Hoehn and Yahr stage 2 (62.4 +/- 12.6 years, five females; ESS score 6.7 +/- 4.7, PDSS score 97.1 +/- 25.6). Age, gender, ESS, and PDSS scores were not significantly different in both groups. However, ESS scores showed an inverse correlation with mean DAT binding in the striatum (r = -0.627, p = 0.03), the caudate nucleus (r = -0.708, p = 0.01), and the putamen (r = -0.599, p = 0.04) in patients with Hoehn and Yahr stage 2. There was no correlation of the ESS score with age, disease duration, UPDRS motor score, PDSS score, or depression score. CONCLUSION: Subjective daytime sleepiness seems to be associated with dopaminergic nigrostriatal degeneration in early PD.

"Are We in Sync with Each Other?" Exploring the Effects of Cosleeping on Heterosexual Couples' Sleep Using Simultaneous Polysomnography: A Pilot Study.

The present study aimed to explore dynamic and interactive aspects of cosleep in heterosexual couples. The sample consisted of eight young healthy adults who belonged to four heterosexual couples with a good relationship quality and a history of cosleeping. All individuals underwent simultaneous polysomnography in a sleep laboratory for four nights in which they slept individually and with their partner. Also, a sleep protocol of subjective sleep measures was completed. Statistical analyses included cross recurrence quantification analysis to assess synchronization during sleep. Cosleeping was associated with better subjective sleep quality, increased total sleep time, sleep efficiency, total slow wave sleep, and REM sleep. Sleep stages were more synchronized during cosleep independent of awakenings. Cardiorespiratory measures remained unchanged. The results indicate that young healthy couples in good relationships benefit from cosleeping on a subjective and objective level. Combining simultaneous polysomnography and cross recurrence quantification analysis is a promising method to study dynamic and interactive aspects of cosleep possibly leading to deeper understanding of the role of sleep for sociality, the nature of REM sleep, and the partner as a social zeitgeber. Moreover, clinical implications may arise from these findings.

Circadian distribution of motor-activity in unilaterally 6-hydroxy-dopamine lesioned rats.

Sleep abnormalities in idiopathic Parkinson's disease (PD) frequently consist in a reduction of total sleep time and efficacy and subsequent excessive daytime sleepiness. As it remains unclear whether these phenomena are part of the disease itself or result from pharmacological treatment, animal models for investigating the pathophysiology of sleep alterations in PD may add knowledge to this research area. In the present study, we investigate whether changes in circadian motor activity occur in 6-OHDA-lesioning model for PD, and allow a screening for disturbed sleep-waking behaviour. Activity measurements of six male Wistar rats with 6-OHDA-lesions in the medial forebrain bundle and six controls were carried out in two consecutive 12:12 h light-dark (LD) cycles. A computer-based video-analysis system, recording the animals' movement tracks was used. Distance travelled and number of transitions between movement periods and resting periods were determined. Although 6-OHDA-lesioned animals show a reduced locomotor activity compared to non-lesioned rats, the circadian distribution basically remained intact. However, some lesioning effects were more pronounced in the resting phase than in the activity phase, possibly paralleling nocturnal akinesia in PD. In order to further elucidate the described phenomena, it will be necessary to perform studies combining sleep recordings with locomotor activity measurements.

Sleep at baseline and after electroconvulsive therapy in patients with major depression.

Sleep in major depressive disorder is frequently altered and possibly indicative for treatment outcomes. For example, increased rapid eye movement (REM-) sleep density seems to predict worse treatment outcomes of psychotherapy. We therefore investigated pre-treatment sleep and sleep changes after termination of electroconvulsive therapy (ECT). Sleep was polysomnographically recorded. The analysed sample consisted of 15 inpatients with ages ranging from 30 to 80 (mean 59 years). ECT was applied two times a week up to 7 weeks. Stable remission of depressive symptoms was defined by a score in the Hamilton Rating Scale of Depression <8 at six months after ECT. The main results were an increase in sleep efficiency and a decrease in the number of awakenings within the course of ECT in the entire patient group. Significant increases in slow wave sleep and REM sleep duration and a significant decrease in REM density were only seen in stable remitters and not in non-remitters. In pre-treatment baseline sleep a higher REM density of the first REM sleep period was significantly associated with better ECT outcome. In conclusion, REM density of the first REM sleep period seems to be an interesting candidate as putative predictor of stable treatment outcome of ECT.

Fate of pre-differentiated mouse embryonic stem cells transplanted in unilaterally 6-hydroxydopamine lesioned rats: histological characterization of the grafted cells.

We transplanted mouse embryonic stem (ES) cells pre-differentiated on a PA6 feeder cell layer into the striatum of 6-hydroxydopamine hemi-lesioned adult rats and studied the fate of the grafted cells 1 and 5 weeks post-grafting. At both time points, ES cell grafts contained tyrosine hydroxylase positive (TH+) and 5-HT immunoreactive cells. Between 1 and 5 weeks, there was an enlargement of the grafts and an increase in number of TH+ cells although the differences between the two time points were not significant. The mean number of TH+ neurons per striatum was 330 +/- 73 after 1 week and 1220 +/- 400 after 5 weeks. Over the same time period, mean soma profile area of the TH+ neurons increased significantly by 25.2%. Neurites were longer after 5 weeks (by 24.9%), but the difference to 1 week post-grafting was not reliable. The percentage of TH+ somata without neurites increased from 6.7% after 1 week to 38.3% after 5 weeks (not significant). After 5 weeks, two out of fifteen graft recipients had tumors indicating that pre-differentiation of mouse embryonic stem cells using this differentiation protocol is not sufficient to prevent tumor formation.

Impairment of sleep-related memory consolidation in schizophrenia: relevance of sleep spindles?

OBJECTIVES: Deficits in declarative memory performance are among the most severe neuropsychological impairments in schizophrenia and contribute to poor clinical outcomes. The importance of sleep for brain plasticity and memory consolidation is widely accepted, and sleep spindles seem to play an important role in these processes. The aim of this study was to test the associations of sleep spindles and picture memory consolidation in patients with schizophrenia and healthy controls. METHODS: We studied 16 patients with schizophrenia on stable antipsychotic medication (mean age ± standard deviation, 29.4 ± 6.4 years) and 16 healthy controls matched for age and educational level. Sleep was recorded and scored according to American Academy of Sleep Medicine (AASM) standard criteria. We performed a picture recognition paradigm and compared recognition performance for neutral and emotional pictures in sleep and wake conditions. RESULTS: Recognition accuracy was better in healthy controls than in patients with schizophrenia in the sleep and wake conditions. However, the memory-promoting effect of sleep was significantly lower in schizophrenia patients than in controls. Sleep spindle activity was reduced in patients, and sleep spindle density was correlated with sleep-associated facilitation of recognition accuracy for neutral pictures. CONCLUSION: Reduced sleep spindles seem to play an important role as a possible mechanism or biomarker for impaired sleep-related memory consolidation in patients with schizophrenia, and are a new target for treatment to improve memory functions and clinical outcomes in these patients.

Assessment of spontaneously occurring periodic limb movements in sleep in the rat.

OBJECTIVE: Periodic limb movements in sleep (PLMS) are often associated with the restless legs syndrome (RLS). Although the dopaminergic system seems to be involved, the pathophysiology of PLMS and RLS is still obscure. The objective of this study is to explore whether a PLMS-like phenomenon can be observed in rodents in order to elucidate the underlying mechanisms. METHODS: In a group of young and old rats (1.4-1.6 and 16.2-20.5 months, respectively), sleep-wake behavior was recorded and hindlimb movements were detected by means of a magneto-inductive device during two 12-h light periods. Furthermore, in the old rats, recordings were made after administration of the dopamine antagonist haloperidol (HAL) on three consecutive days. Periodic hindlimb movements (PHLM) during nonrapid eye movement sleep (NREM) were identified according to modified human criteria. RESULTS: In the young animals, no PHLM were observed, whereas, 4 out of 10 old rats showed PHLM, two of them have more than 5 PHLM/h. Haloperidol affects neither the sleep pattern nor the number of PHLM. Interestingly, the percentage of old rats spontaneously displaying PHLM resembles the prevalence of PLMS in the elderly. CONCLUSIONS: Our study demonstrates for the first time that periodic hindlimb movements (PHLM) in sleep can occur spontaneously in rats. A clear effect of age on this phenomenon was seen, with only old animals displaying PHLM. To validate whether the observed PHLM constitute a good model for human PLMS or even RLS, their pharmacological properties need to be characterized in a large number of PHLM positive animals.

The effect of intranasal orexin-A (hypocretin-1) on sleep, wakefulness and attention in narcolepsy with cataplexy.

Narcolepsy with cataplexy is a sleep dysregulation disorder with alterations of REM sleep, i.e., sleep onset REM periods and REM sleep instability. Deficient orexin-A (hypocretin-1) signaling is assumed to be a major cause of narcolepsy with cataplexy. In this study we investigated fourteen subjects with narcolepsy with cataplexy in a within-subject, random-order crossover, placebo-controlled design. Patients received double-blinded intranasal orexin-A (435 nmol) or sterile water (placebo) in the morning. Administration was preceded by an adaptation night and followed by a modified maintenance of wakefulness test, attention testing and a second full night of polysomnographic recording. We found comparable sleep behavior during the adaptation nights between both conditions. After orexin-A administration patients had less wake-REM sleep transitions and a decreased REM sleep duration. In the subsequent night, patients showed an increased N2 duration. In the test of divided attention, patients had fewer false reactions after orexin-A administration. Our results support orexin-A to be a REM sleep stabilizing factor and provide functional signs for effects of orexin-A on sleep alterations and attention in narcolepsy with cataplexy.

Effects of blockade of peripheral interleukin-6 trans-signaling on hippocampus-dependent and independent memory in mice.

Besides functions of the interleukin-6 (IL-6)/gp130 cytokine family in immunology, IL-6 signaling has influence on memory processes. IL-6 acts on target cells via a membrane-bound IL-6 receptor (IL-6R) and subsequent association with the signal-transducing protein gp130. While gp130 is expressed on all cells in the body, IL-6R is expressed in only on few cells such as hepatocytes and some leukocytes. Cells lacking IL-6R were shown not to be responsive to the cytokine. Interestingly, a soluble form of the IL-6R in complex with IL-6 can stimulate cells that do not express the membrane-bound IL-6R. This signaling pathway has been called IL-6 trans-signaling. IL-6 trans-signaling can specifically be blocked by a soluble gp130 protein (sgp130Fc) without affecting IL-6 classic signaling via the membrane-bound IL-6R. Transgenic mice expressing sgp130Fc in the blood, but not in the central nervous system, were analyzed for hippocampus-dependent and independent memory, together with exploratory- and anxiety-related behavior. Transgenic animals did not show impaired hippocampus-dependent or independent learning and memory. However, compared to wild-type animals, they showed reduced exploratory behavior and an increased thermal pain threshold, indicating that these effects depend on IL-6 trans-signaling. These results bear important consequences for the therapeutic blockade of IL-6 activity in autoimmune diseases.

Effects of daytime naps on procedural and declarative memory in patients with schizophrenia.

Sleep has been identified as a state that optimizes the consolidation of newly acquired information in memory. Straight memory deficits and sleep disturbances are well-known in patients with schizophrenia. This study tested the hypothesis that patients with schizophrenia have a deficit in procedural and declarative memory consolidation after a short midday nap when compared to healthy controls and patients with remitted to moderate major depression. Following a normal night's sleep, 22 healthy subjects, 20 patients with major depression and 21 patients with schizophrenia were studied in a napping and wake condition in a random-order cross-over design, early in the afternoon. To test declarative memory, the Rey-Osterrieth Complex Figure Test respectively the Taylor Complex Figure Test and, for procedural learning, a mirror tracing task were performed. The present study is the first to demonstrate significant differences between individuals with schizophrenia, depression and healthy matched controls with regard to measures of sleep and memory performance after a short period of daytime sleep (napping). In particular we found that a daytime nap of only about 40min led to improvement of declarative memory performance in all investigated groups, whereas no beneficial effect was seen on procedural performance in the group of medicated patients with schizophrenia in contrast to healthy controls and patients with remitted to moderate major depression.