Högskolan i Skövde

This article presents a taxonomy of altered states of consciousness, primarily based on their central phenomenological features. Following taxonomic principles and a modified Delphi methodology, a multidisciplinary, international group identified eight distinct phenomenological/behavioral states (some with subcategories): proto and transitional, delirium, minimal to no awareness, experiential detachment, enhanced physicality, altered identity, imaginary/fantasy/visionary, and unity/mystical. We hope this taxonomy will be discussed and developed further, fostering conceptual clarity and stimulating research and integration across different specializations. A nuanced discussion of different states should reveal what is common and different across different triggers and antecedents of altered states of consciousness, and encourage their phenomenological, psychological, cultural, and neuroscientific understanding. This will pave the way for an integrated understanding of different modalities of experiencing.

Magneto/electroencephalography (M/EEG) studies of dreaming are an essential paradigm in the investigation of neurocognitive processes of human consciousness during sleep, but they are limited by the number of observations that can be collected per study. Dream research also involves substantial methodological and conceptual variability, which poses problems for the integration of results. To address these issues, here we present the DREAM database-an expanding collection of standardized datasets on human sleep M/EEG combined with dream report data-with an initial release comprising 20 datasets, 505 participants, and 2643 awakenings. Each awakening consists, at minimum, of sleep M/EEG ( ≥ 20 s, ≥100 Hz, ≥2 electrodes) up to the time of waking and a standardized dream report classification of the subject's experience during sleep. We observed that reports of conscious experiences can be predicted with objective features extracted from EEG recordings in both Rapid Eye Movement (REM) and non-REM (NREM) sleep. We also provide several examples of analyses, showcasing the database's high potential in paving the way for new research questions at a scale beyond the capacity of any single research group.

Objective: To investigate how a range of variables, both physiological (sleep architecture, serum follicle-stimulating hormone (S-FSH), anthropometric and blood pressure measures) and non-physiological (stressful life events, education), are associated with symptoms of distress, anxiety, and depression from premenopause to postmenopause and at postmenopause.

Methods: We recruited 64 women (ages 45–47). Data were derived from an in-house questionnaire, the Brief Symptom Inventory, State-Trait Anxiety Inventory, Beck Depression Inventory, a sleep questionnaire, physiological measurements, and polysomnography at baseline and at ten-year follow-up.

Results: During the follow-up, an increase in weight was associated with an increase in anxiety as recorded by the Brief Symptom Inventory (p = 0.012, R2 = 0.117). Cross-sectionally, at postmenopause, state anxiety was associated with an increase in blood pressure and S-FSH, delayed REM sleep, and the use of menopausal hormone therapy (pSTAI-S < 0.001, R2 = 0.343). Distress and depressive symptoms were associated with stressful life events and a lower level of education but also with an increase in diastolic blood pressure and use of hormone therapy (pBSI < 0.001, R2 = 0.328 and pBDI < 0.001, R2 = 0.312). Sleep disruptions were associated with psychological symptoms but vasomotor symptoms were not.

Conclusions: The change in psychological symptoms during the follow-up was modest. At postmenopause, distress and depressive symptoms were associated with a range of physiological and non-physiological parameters, but state anxiety only with physiological parameters. At postmenopause, psychological symptoms were more sensitive to sleep disruptions than were vasomotor symptoms. 

Background: The ability of current depth-of-anaesthesia monitors to differentiate subtle changes in the conscious state has not been well characterised. We examine the variability in bispectral index (BIS) scores associated with disconnected conscious and unconscious states as confirmed by a novel serial awakening paradigm. Methods: Seventy adult participants, given propofol or dexmedetomidine, had a cumulative 1381 electroencephalographic (EEG) recordings across two centres. Participants were awakened periodically, and their recent conscious experience interrogated by structured questioning. BIS were reconstructed from EEG using openibis, and the distribution of BIS scores were compared using linear mixed effects modelling. The predictive capacity of BIS across states of consciousness was also examined. Results: Reconstructed BIS scores correlated significantly with blood concentrations of propofol and dexmedetomidine (all P<0.001). However, while the average BIS was different between baseline wakefulness (mean BIS=95.1 [standard deviation=3.5]); connected consciousness with drug present (84.0 [10.9]); disconnected consciousness (70.0 [16.9]); and unconsciousness (68.1 [16.1]), the interquartile range of these states (3.6, 15.1, 23.3 and 26.8, respectively) indicated high degrees of overlap and individual variability. Connected consciousness could be differentiated from either disconnected consciousness or unconsciousness with 86% accuracy (i.e. 14% error rate), and disconnected consciousness differentiated from unconsciousness with 74% accuracy. Conclusions: These results agree with previous studies that BIS scores fail to reliably differentiate between states of consciousness, exacerbated by segregating connected, disconnected, and unconscious states. To develop a method that reliably identifies the conscious state of an individual (not an average), work is needed to establish the causal mechanisms of disconnection and unconsciousness. 

Despite a surge of studies on the effects of COVID-19 on our well-being, we know little about how the pandemic is reflected in people's spontaneous thoughts and experiences, such as mind-wandering (or daydreaming) during wakefulness and dreaming during sleep. We investigated whether and how COVID-19-related general concern, anxiety, and daily worry are associated with the daily fluctuation of the affective quality of mind-wandering and dreaming, and to what extent these associations can be explained by poor sleep quality. We used ecological momentary assessment by asking participants to rate the affect they experienced during mind-wandering and dreaming in daily logs over a 2-week period. Our preregistered analyses based on 1,755 dream logs from 172 individuals and 1,496 mind-wandering logs from 152 individuals showed that, on days when people reported higher levels of negative affect and lower levels of positive affect during mind-wandering, they experienced more worry. Only daily sleep quality was associated with affect experienced during dreaming at the within-person level: on nights with poorer sleep quality people reported experiencing more negative and less positive affect in dreams and were more likely to experience nightmares. However, at the between-person level, individuals who experienced more daily COVID-19 worry during the study period also reported experiencing more negative affect during mind-wandering and during dreaming. As such, the continuity between daily and nightly experiences seems to rely more on stable trait-like individual differences in affective processing. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Objectives: The objective of this study was to investigate how blood pressure, sleep architecture, sleep-disordered breathing, body habitus, and levels of serum follicle-stimulating hormone are associated with symptoms of insomnia and sleep quality during menopausal transition.

Methods: 64 healthy premenopausal women (aged 45–47 years) were recruited to the study. Data were collected at baseline and at 10-year follow-up during sleep laboratory and laboratory visits. A sleep questionnaire was used to evaluate sleep quality and insomnia symptoms. Data were analysed using multiple linear and logistic regression with a backward method.

Results: During the menopausal transition, a change in insomnia symptoms was associated with a change in morning systolic blood pressure (β = 0.114 (CI95% 0.023–0.205), p = 0.016). At follow-up, at the age of 56, a higher percentage of REM sleep was associated with a lower odds of restless sleep (OR = 0.842 (95 % CI 0.742–0.954), p = 0.007), while both higher systolic and diastolic evening blood pressure was associated with an increased odds of morning tiredness. OR = 1.047 (95 % CI 1.003–1.092), p = 0.034 and OR = 1.126 (95 % CI 1.018–1.245), p = 0.007, respectively.

Conclusions: In healthy midlife women, a change blood pressure is related to the development of insomnia symptoms during menopausal transition. In postmenopausal women, a high evening blood pressure may be associated with morning tiredness and a reduced amount of REM sleep may be perceived as restless sleep. 

Nightmares are vivid, extended, and emotionally negative or negative dreams that awaken the dreamer. While sporadic nightmares and bad dreams are common and generally harmless, frequent nightmares often reflect underlying pathologies of emotional regulation. Indeed, insomnia, depression, anxiety, or alcohol use have been associated with nightmares in epidemiological and clinical studies. However, the connection between nightmares and their comorbidities are poorly understood. Our goal was to examine the genetic risk factors for nightmares and estimate correlation or causality between nightmares and comorbidities. We performed a genome-wide association study (GWAS) in 45,255 individuals using a questionnaire-based assessment on the frequency of nightmares during the past month and genome-wide genotyping data. While the GWAS did not reveal individual risk variants, heritability was estimated at 5%. In addition, the genetic correlation analysis showed a robust correlation (rg > 0.4) of nightmares with anxiety (rg = 0.671, p = 7.507e−06), depressive (rg = 0.562, p = 1.282e−07) and posttraumatic stress disorders (rg = 0.4083, p = 0.0152), and personality trait neuroticism (rg = 0.667, p = 4.516e−07). Furthermore, Mendelian randomization suggested causality from insomnia to nightmares (beta = 0.027, p = 0.0002). Our findings suggest that nightmares share genetic background with psychiatric traits and that insomnia may increase an individual’s liability to experience frequent nightmares. Given the significant correlations with psychiatric and psychological traits, it is essential to grow awareness of how nightmares affect health and disease and systematically collect information about nightmares, especially from clinical samples and larger cohorts. 

Previous research indicates that the COVID-19 pandemic has affected dreaming negatively. We compared 1132 dreams collected with prospective two-week dream diary during the pandemic to 166 dreams collected before the pandemic. We hypothesized that the pandemic would increase the number of threatening events, threats related to diseases, and the severity of threats. We also hypothesized that dreams that include direct references to the pandemic will include more threatening events, more disease-related threats, and more severe threats. In contradiction with our hypotheses, results showed no differences between pandemic and pre-pandemic samples in the number of threats, threats related to diseases, or severe threats. However, dreams with direct references to the pandemic had more threats, disease-related threats, and severe threats. Our results thus do not suggest a significant overall increase in nightmarish or threatening dream content during the pandemic but show a more profound effect on a minority of dreams. 

Episodic memories of emotionally salient and personally significant events are often incorporated into dreams, although rarely replayed identically to the original waking event except in replicative posttraumatic nightmares. We investigated, in five Swedish female 2004 Indian Ocean tsunami survivors, how episodic memories of the catastrophe were reflected in their dreams after trauma, both in retrospectively recalled nightmares and bad dreams, and in prospective dream diaries completed several months after the catastrophe. We also assessed whether the emotional and threatening dream content differed between the trauma and a matched control group. Based on the threat simulation theory, we predicted that the trauma group dreams would portray notable similarities with elements related to the original tsunami trauma, and that the trauma group would demonstrate a higher prevalence of negative emotional states, and a higher frequency of threatening dream events as well as more severe threats in their dreams. Only the first hypothesis was partially supported, with retrospective nightmares bearing higher similarity to the trauma experience than the prospective dream diary dreams. However, we observed no statistically significant differences in emotional or threatening dream content between the groups, suggesting that the trauma group participants were not suffering from significant posttraumatic dreaming at the time of systematic dream data collection. Yet, specific features of the trauma group dreams might be interpreted as remnants of episodic tsunami-related memories: Their dreams had a higher percentage of life-threatening events depicting realistic but improbable threats, and an analysis of water-related themes evidenced stressful themes related to waves.