Abstract
While there is an extensive literature on predisposing, precipitating, coping, and perpetuating factors in those with chronic insomnia, very little work has been undertaken to evaluate these ...factors over the early developmental course of insomnia. The present aim was to determine whether several hypothesized factors in each domain (predisposing, precipitating, coping, and perpetuating), assessed during an episode of acute insomnia (AI), are related to its persistence or remission to normal sleep. Participants comprised n = 140 people with AI and n = 737 normal sleepers (NS) recruited from the general public. Participants completed measures assessing predisposing characteristics (personality traits, arousal predisposition, and insomnia vulnerability), precipitating events and outcomes (life events, perceived stress, anxiety, and depression), coping styles (thought control strategies and coping styles), and perpetuating factors (sleep preoccupation, pre-sleep arousal, dysfunctional beliefs, and fatigue). Additionally, insomnia status (from AI at baseline to its persistence or natural remission NR) was assessed 1 month later (n = 129). Baseline differences between NS and individuals with AI were observed in each domain with increasing age, lower openness to experience and conscientiousness, higher insomnia severity, levels of anxiety, and affective sleep preoccupation significantly predicting AI status. Further, a previous episode of insomnia, higher depression scores, and affective sleep preoccupation scores significantly predicted its persistence, as opposed to its NR. Results are discussed with reference to the conceptualization of insomnia and how the findings may influence the design of preventative interventions to circumvent the transition from acute to chronic insomnia.
Insomnia is prevalent, severe and partially heritable. Unfortunately, its neuronal correlates remain enigmatic, hampering the development of mechanistic models and rational treatments. Consistently ...reported impairments concern fragmented sleep, hyper-arousal and executive dysfunction. Because fronto-striatal networks could well play a role in sleep, arousal regulation and executive functioning, the present series of studies used an executive task to evaluate fronto-striatal functioning in disturbed sleep. Patients with insomnia showed reduced recruitment of the head of the left caudate nucleus during executive functioning, which was not secondary to altered performance or baseline perfusion. Individual differences in caudate recruitment were associated with hyper-arousal severity. Seed-based functional connectivity analysis suggested that attenuated input from a projecting orbitofrontal area with reduced grey matter density contributes to altered caudate recruitment in patients with insomnia. Attenuated caudate recruitment persisted after successful treatment of insomnia, warranting evaluation as a potential vulnerability trait. A similar selective reduction in caudate recruitment could be elicited in participants without sleep complaints by slow-wave sleep fragmentation, providing a model to facilitate investigation of the causes and consequences of insomnia.
Diffusion magnetic resonance imaging is increasingly used as a non-invasive method to investigate white matter structure in neurological and neuropsychiatric disease. However, many options are ...available for the acquisition sequence and analysis method. Here we used Parkinson's disease as a model neurodegenerative disorder to compare imaging protocols and analysis options. We investigated fractional anisotropy and mean diffusivity of white matter in patients and age-matched controls, comparing two datasets acquired with different imaging protocols. One protocol prioritised the number of b value acquisitions, whilst the other prioritised the number of gradient directions. The dataset with more gradient directions was more sensitive to reductions in fractional anisotropy in Parkinson's disease, whilst the dataset with more b values was more sensitive to increases in mean diffusivity. Moreover, the areas of reduced fractional anisotropy were highly similar to areas of increased mean diffusivity in PD patients. Next, we compared two widely used analysis methods: tract-based spatial statistics identified reduced fractional anisotropy and increased mean diffusivity in Parkinson's disease in many of the major white matter tracts in the frontal and parietal lobes. Voxel-based analyses were less sensitive, with similar patterns of white matter pathology observed only at liberal statistical thresholds. We also used tract-based spatial statistics to identify correlations between a test of executive function (phonemic fluency), fractional anisotropy and mean diffusivity in prefrontal white matter in both Parkinson's disease patients and controls. These findings suggest that in Parkinson's disease there is widespread pathology of cerebral white matter, and furthermore, pathological white matter in the frontal lobe may be associated with executive dysfunction. Diffusion imaging protocols that prioritised the number of directions versus the number of b values were differentially sensitive to alternative markers of white matter pathology, such as fractional anisotropy and mean diffusivity.
► DTI shows abnormal frontal white matter in Parkinson's disease. ► FA and MD in the frontal lobe correlate with executive function in PD. ► The number of directions and b values affects sensitivity to FA/MD changes in PD. ► TBSS is more sensitive than VBM to white matter change in Parkinson's disease.
The volitional impairments of alien limb and apraxia are a defining feature of the corticobasal syndrome, but a limited understanding of their neurocognitive aetiology has hampered progress towards ...effective treatments. Here we combined several key methods to investigate the mechanism of impairments in voluntary action in corticobasal syndrome. We used a quantitative measure of awareness of action that is based on well-defined processes of motor control; structural and functional anatomical information; and evaluation against the clinical volitional disorders of corticobasal syndrome. In patients and healthy adults we measured 'intentional binding', the perceived temporal attraction between voluntary actions and their sensory effects. Patients showed increased binding of the perceived time of actions towards their effects. This increase correlated with the severity of alien limb and apraxia, which we suggest share a core deficit in motor control processes, through reduced precision in voluntary action signals. Structural neuroimaging analyses showed the behavioural variability in patients was related to changes in grey matter volume in pre-supplementary motor area, and changes in its underlying white matter tracts to prefrontal cortex. Moreover, changes in functional connectivity at rest between the pre-supplementary motor area and prefrontal cortex were proportional to changes in binding. These behavioural, structural and functional results converge to reveal the frontal network for altered awareness and control of voluntary action in corticobasal syndrome, and provide candidate markers to evaluate new therapies.
Objective:
The study goal was to test whether induced stress during driving could be measured at the event level through electrodermal activity responses.
Background:
Stress measured in simulation ...scenarios could thus far show an overall change in the stress state, but not be well attributed to acute stressful events. Driving simulator scenarios that induce stress measurable at the event level in realistic situations are thus warranted. As such, acute stress reactions can be measured in the context of changing situational factors such as fatigue, substance abuse, or medical conditions.
Method:
Twelve healthy female participants drove the same route numerous times in a driving simulator, each time with different random traffic events occurring throughout. During one of the scenarios, unknown to the participants, 10 programmed neutral traffic events occurred, whereas in another scenario, at the same location, 10 stressful events occurred.
Results:
Electrodermal response results showed both effects of scenario type and of events. The amplitude of the electrodermal response was significantly correlated with subjective stress experience.
Conclusion:
We conclude that our developed ecological driving simulation scenarios can be used to induce and measure stress at the event level.
Application:
The developed simulator scenarios enable us to measure stress reactions in driving situations at the time when the event actually happens. With these scenarios, we can measure how situational factors, such as fatigue or substance abuse, can change immediate stress reactions when driving. We can further measure more specifically how induced driving stress can affect physical and mental functioning afterward.
Summary
Although complaints of impaired daytime functioning are essential to the diagnosis of primary insomnia, objective evidence for cognitive dysfunction has been hard to establish. A prerequisite ...for understanding the neurocognitive consequences of primary insomnia is to establish task paradigms that robustly differentiate insomniacs from well‐sleeping subjects. We hypothesized that the decline in performance that typically occurs with an increasing cognitive demand would provide a more sensitive measure than performance on a single task version. The hypothesis was tested, first, by assessing the performance on two vigilance tasks with different cognitive demands in 25 elderly patients with primary insomnia and 13 healthy well‐sleeping age‐matched subjects. Secondly, we investigated the performance response to sleep therapy using a waiting‐list controlled design. Sleep therapy consisted of a multi‐component intervention including sleep restriction, cognitive behavioral therapy, bright‐light therapy, structured physical activity and body temperature manipulations. The results show that insomniacs differed markedly from controls in their reaction times across tasks with different cognitive demands: patients responded faster on the ‘simple’ vigilance task, yet slower on the ‘complex’ vigilance task. Sleep therapy effectively restored normal performance: patients became significantly slower on the ‘simple’ task and faster on the ‘complex’ task, returning to the performance levels of control subjects. These findings indicate that the performance decline associated with increasing cognitive demands is possibly the first sensitive and robust measure of the neurocognitive sequelae of insomnia. We suggest that future studies on cognition in primary insomnia should apply a design that varies task demands.
•Dizziness is a highly prevalent burden in the middle-aged and elderly.•Poor sleep quality is associated with dizziness in the general population.•The association between sleep and dizziness is ...stronger for non-vestibular dizziness.•sleep is important to assess in those presenting with dizziness.
Dizziness is a physical and mental burden that affects 33% of the population at age 70. Research in clinical samples suggests that poor sleep may contribute to dizziness complaints, but this has yet to be determined in the general population. We assessed the association of self-reported and actigraphy-estimated sleep with dizziness in a population-based sample.
Data of 4702 participants from the population-based Rotterdam Study, included between 2011 and 2014, were analyzed (mean age: 65.8 years, 55.7% women). Sleep quality was measured with the Pittsburgh Sleep Quality Index. Experience of dizziness and associated characteristics were self-reported, characteristics were categorized as vestibular or non-vestibular. A subsample of 1440 participants (mean age: 64.9 years, 51.3% women) wore an actigraph for a median of 7 days to allow objective estimation of total sleep time, sleep efficiency, sleep onset latency, and wake after sleep onset. We used logistic regression to assess the associations between different sleep parameters and dizziness.
Poor self-reported sleep quality was associated with more dizziness (OR = 1.065, 95% CI: 1.043 to 1.087). This effect size was somewhat larger for dizziness with non-vestibular characteristics (OR = 1.108, 1.069 to 1.149) than for dizziness with vestibular characteristics (OR = 1.062, 0.988 to 1.142). Actigraphy-estimated sleep parameters were not associated with dizziness.
A poor self-reported sleep quality is associated with more dizziness in a population-based sample of middle-aged and elderly persons. We encourage clinicians to assess sleep quality in patients presenting with dizziness, and vice versa.
The dynamic of the temporal correlations between brain areas, called functional connectivity (FC), undergoes complex transformations through the life span. In this review, we aim to provide an ...overview of these changes in the nonpathological brain from fetal life to advanced age. After a brief description of the main methods, we propose that FC development can be divided into four main phases: first, before birth, a strong change in FC leads to the emergence of functional proto‐networks, involving mainly within network short‐range connections. Then, during the first years of life, there is a strong widespread organization of networks which starts with segregation processes followed by a continuous increase in integration. Thereafter, from adolescence to early adulthood, a refinement of existing networks in the brain occurs, characterized by an increase in integrative processes until about 40 years. Middle age constitutes a pivotal period associated with an inversion of the functional brain trajectories with a decrease in segregation process in conjunction to a large‐scale reorganization of between network connections. Studies suggest that these processes are in line with the development of cognitive and sensory functions throughout life as well as their deterioration. During aging, results support the notion of dedifferentiation processes, which refer to the decrease in functional selectivity of the brain regions, resulting in more diffuse and less specialized FC, associated with the disruption of cognitive functions with age. The inversion of developmental processes during aging is in accordance with the developmental models of neuroanatomy for which the latest matured regions are the first to deteriorate.
ABSTRACT
In the current global home confinement situation due to the COVID‐19 outbreak, most individuals are exposed to an unprecedented stressful situation of unknown duration. This may not only ...increase daytime stress, anxiety and depression levels, but also disrupt sleep. Importantly, because of the fundamental role that sleep plays in emotion regulation, sleep disturbance can have direct consequences upon next day emotional functioning. In this paper, we summarize what is known about the stress−sleep link and confinement as well as effective insomnia treatment. We discuss those effects of the current home confinement situation that can disrupt sleep but also those that could benefit sleep quality. We suggest adaptions of cognitive behavioural therapy elements that are feasible to implement for those facing changed work schedules and requirements, those with health anxiety and those handling childcare and home‐schooling, whilst also recognizing the general limitations imposed on physical exercise and social interaction. Managing sleep problems as best as possible during home confinement can limit stress and possibly prevent disruptions of social relationships.
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