REM sleep and memory reorganization: Potential relevance for psychiatry and psychotherapy.

Sleep can foster the reorganization of memory, i.e. the emergence of new memory content that has not directly been encoded. Current neurophysiological and behavioral evidence can be integrated into a model positing that REM sleep particularly promotes the disintegration of existing schemas and their recombination in the form of associative thinking, creativity and the shaping of emotional memory. Particularly, REM sleep related dreaming might represent a mentation correlate for the reconfiguration of memory. In a final section, the potential relevance for psychiatry and psychotherapy is discussed.

Brain-derived neurotrophic factor genetic polymorphism rs6265 and creativity.

The protein brain-derived neurotrophic factor (BDNF) promotes neural plasticity of the central nervous system and plays an important role for learning and memory. A single nucleotide polymorphism (rs6265) at position 66 in the pro-region of the human BDNF gene, resulting in a substitution of the amino acid valine (val) with methionine (met), leads to attenuated BDNF secretion and has been associated with reduced neurocognitive function. Inhomogeneous results have been found regarding the effect of the BDNF genotype on behavior. We determined the BDNF genotype and performance on the Compound Remote Associate (CRA) task as a common measure of creativity in 76 healthy university students. In our main analyses, we did not find significant differences between met-carriers (n = 30) and non-met carriers (n = 46). In a secondary analysis, we found that met-carriers had a slower solution time (medium effect size) for items of medium difficulty. Our results suggest that met-carriers and non-met-carriers do not generally differ regarding their creativity, but non-met-carriers may have a certain advantage when it comes to moderately difficult problems. The wider literature suggests that both genetic variants come with advantages and disadvantages. Future research needs to sharpen our understanding of the disadvantages and, potentially, advantages met allele carriers may have.

Become your own SLEEPexpert: design, implementation, and preliminary evaluation of a pragmatic behavioral treatment program for insomnia in inpatient psychiatric care.

Study Objectives: The majority of patients with mental disorders suffer from insomnia, associated with adverse health outcomes. Cognitive behavioral therapy for insomnia (CBT-I) represents the first-line treatment, but is too complex for severely ill patients and not systematically implemented in inpatient psychiatric care. This project aimed to develop a pragmatic behavioral treatment program that empowers inpatients with severe mental disorders to take care of their own sleep health. Methods: CBT-I was adapted based on implementation research involving 24 inpatients with psychiatric disorders across diagnostic entities and comorbid insomnia and 30 health care providers at the University Hospital of Psychiatry and Psychotherapy, Bern. The program was implemented and evaluated by 15 patients and 22 health care providers based on interviews and questionnaires before participation and prior to discharge. Results: Implementation research resulted in the SLEEPexpert intervention, centering on bedtime restriction and circadian adaptation in three phases; therapist-guided treatment initiation, self-management with nursing support, and self-management. Evaluative pre-post assessments in 15 patients demonstrated feasibility. Time in bed decreased by 60 minutes (520 ± 105.3 vs. 460 ± 78.1, p = 0.031, d = 0.6) and total sleep time increased by around 45 minutes (331 ± 110.6 vs. 375 ± 74.6, p = 0.09, d = 0.5), resulting in increased sleep efficiency (65.3 ± 21.8 vs. 81.9 ± 11.2%, p = 0.011, d = 0.8). Patients improved on the Insomnia Severity Index (18.3 ± 4.6 vs. 11.4 ± 4.4, p < 0.001, d = 1.2) and Pittsburgh Sleep Quality Index (12.9 ± 3.8 vs. 10.3 ± 3.3, p = 0.031, d = 0.6). Conclusions: We propose a new pragmatic behavioral treatment program (SLEEPexpert) customized to the needs of patients and health care providers in inpatient psychiatric care. Data demonstrate feasibility. An improvement of insomnia severity was observed, but a control comparison is needed to further test for efficacy.

Sleep Strengthens but does Not Reorganize Memory Traces in a Verbal Creativity Task.

STUDY OBJECTIVES: Sleep after learning promotes the quantitative strengthening of new memories. Less is known about the impact of sleep on the qualitative reorganization of memory content. This study tested the hypothesis that sleep facilitates both memory strengthening and reorganization as indexed by a verbal creativity task. METHODS: Sixty healthy university students (30 female, 30 male, 20-30 years) were investigated in a randomized, controlled parallel-group study with three experimental groups (sleep, sleep deprivation, daytime wakefulness). At baseline, 60 items of the Compound Remote Associate (CRA) task were presented. At retest after the experimental conditions, the same items were presented again together with 20 new control items to disentangle off-line incubation from online performance effects. RESULTS: Sleep significantly strengthened formerly encoded memories in comparison to both wake conditions (improvement in speed of correctly resolved items). Offline reorganization was not enhanced following sleep, but was enhanced following sleep-deprivation in comparison to sleep and daytime wakefulness (solution time of previously incubated, newly solved items). Online performance did not differ between the groups (solution time of new control items). CONCLUSIONS: The results support the notion that sleep promotes the strengthening, but not the reorganization, of newly encoded memory traces in a verbal creativity task. Future studies are needed to further determine the impact of sleep on different types of memory reorganization, such as associative thinking, creativity and emotional memory processing, and potential clinical translations, such as the augmentation of psychotherapy through sleep interventions.