Executive brain functions after exposure to nocturnal traffic noise: effects of task difficulty and sleep quality

Impairment of executive functions due to sleep alterations: An integrative review on the use of P300

Objective

Cognitive impairment due to sleep deprivation (SD) is an important global health concern as part of the growing rates of sleep disorders and sleep deprivation worldwide. Amongst the affected cognitive processes, the effects of SD on the executive functions (EFs) show diverse methods and inconclusive or contradictory results, highlighting the importance of further research in this field. Considering this scenario, we evaluate one of the most used methods for objectively evaluating EFs on SD: the event-related potential (ERP) P300.

Methods

Our study provides a comprehensive review on the use of P300 for evaluating executive functions in sleep alterations on subjects of all ages, as well as an analysis on the efficiency of P300 as an assessment method for executive functions compared to traditional neurocognitive batteries. We review the benefits of P300 application for multiple sleep/wake alterations, whether evoked in laboratory or as part of pre-existing sleep disorders.

Results

We assess the diverse protocols used to elicit and complement P300, the most identified alterations in amplitude and latency, and suggest new lines of study that could benefit from P300 within the field.

Conclusion

We conclude that P300 is a valuable asset for evaluating executive dysfunction under sleep deprivation both as a standalone protocol and in conjunction with subjective methods, with consistently significant results in assessing executive dysfunction in a diversity of subjects and etiologies.

Bottom-Up and Top-Down Attention Impairment Induced by Long-Term Exposure to Noise in the Absence of Threshold Shifts

Objective

We aimed to assess the effect of noise exposure on bottom-up and top-down attention functions in industrial workers based on behavioral and brain responses recorded by the multichannel electroencephalogram (EEG).

Method

In this cross-sectional study, 563 shipyard noise-exposed workers with clinical normal hearing were recruited for cognitive testing. Personal cumulative noise exposure (CNE) was calculated with the long-term equivalent noise level and employment duration. The performance of cognitive tests was compared between the high CNE group (H-CNE, >92.2) and the low CNE group; additionally, brain responses were recorded with a 256-channel EEG from a subgroup of 20 noise-exposed (NG) workers, who were selected from the cohort with a pure tone threshold <25 dB HL from 0.25 to 16 kHz and 20 healthy controls matched for age, sex, and education. P300 and mismatch negativity (MMN) evoked by auditory stimuli were obtained to evaluate the top-down and bottom-up attention functions. The sources of P300 and MMN were investigated using GeoSource.

Results

The total score of the cognitive test (24.55 ± 3.71 vs. 25.32 ± 2.62, p < 0.01) and the subscale of attention score (5.43 ± 1.02 vs. 5.62 ± 0.67, p < 0.001) were significantly lower in the H-CNE group than in the L-CNE group. The attention score has the fastest decline of all the cognitive domain dimensions (slope = -0.03 in individuals under 40 years old, p < 0.001; slope = -0.06 in individuals older than 40 years old, p < 0.001). When NG was compared with controls, the P300 amplitude was significantly decreased in NG at Cz (3.9 ± 2.1 vs. 6.7 ± 2.3 μV, p < 0.001). In addition, the latency of P300 (390.7 ± 12.1 vs. 369.4 ± 7.5 ms, p < 0.001) and MMN (172.8 ± 15.5 vs. 157.8 ± 10.5 ms, p < 0.01) was significantly prolonged in NG compared with controls. The source for MMN for controls was in the left BA11, whereas the noise exposure group's source was lateralized to the BA20.

Conclusion

Long-term exposure to noise deteriorated the bottom-up and top-down attention functions even in the absence of threshold shifts, as evidenced by behavioral and brain responses.

The role of depressive symptoms within the association of long-term exposure to indoor and outdoor traffic noise and cognitive function - Results from the Heinz Nixdorf Recall study

OBJECTIVES

Traffic noise is negatively associated with cognitive function, and its perception can differ between depressed and non-depressed people. We studied the role of depressive symptoms in the association between traffic noise and cognitive function. We studied the role of depressive symptoms in the association between traffic noise and cognitive function.

METHODS

During the first follow-up examination (2006-2008) of the German Heinz Nixdorf Recall study, cognitive function (five subtests and an additive global summary score, GCS) and depressive symptoms (CES-D score) were assessed in 2745 participants (aged 50-80, 49.8% women). Mild cognitive impairment (MCI) was diagnosed according to the Petersen criteria in 380 participants. Long-term exposure to traffic noise was modeled as weighted 24-h mean (L_DEN) and night-time mean (L_NIGHT) at the façade of the baseline addresses, and was corrected for indoors (L_{DEN_IN} and L_{NIGHT_IN}). We developed multiple linear and logistic regression models adjusted for individual-level characteristics to investigate cross-sectionally the role of depressive symptoms in the association of traffic noise with cognitive function.

RESULTS

Overall, 8.6% participants had depressive symptoms. The median noise values were L_DEN 52.1 dB(A) and L_{DEN_IN} 34.7 dB(A). Associations were slightly stronger for cognitive subtests in those with severe depression (CES-D>21), i.e., per 10 dB(A) L_DEN and verbal fluency: β = -0.04 [-0.11; 0.03] for CES-D≤21 and β = -0.09 [-0.24; -0.06] for CES-D>21. Additional adjustment of the main model for CES-D did not change the association between noise and cognitive outcomes. Estimates using indoor noise exposure were generally stronger and more precise.

CONCLUSIONS

Depressed people may be more susceptible to adverse effects of noise than non-depressed. Modeled estimates of indoor noise exposure is possibly a more appropriate measure of exposure.

Associations of Air Pollution and Noise with Local Brain Structure in a Cohort of Older Adults

BACKGROUND

Despite the importance of understanding associations of air pollution and noise exposure with loss of neurocognitive performance, studies investigating these exposures and local brain structure are limited.

OBJECTIVE

We estimated associations of residential air pollution and noise exposures with neurocognitive test performance and the local gyrification index (lGI), a marker for local brain atrophy, among older adults.

METHODS

For n=615 participants from the population-based 1000BRAINS study, based on the German Heinz Nixdorf Recall study, we assessed residential exposures to particulate matter (PM10, PM2.5, PM2.5abs), accumulation mode particle number (PNAM), and nitrogen oxides (NOx, NO2), using land-use regression and chemistry transport models. Weighted 24-h and nighttime noise were modeled according to the European noise directive. We evaluated associations of air pollution and noise exposure at the participants' 2006-2008 residential addresses with neurocognitive test performance and region-specific lGI values (n=590) from magnetic resonance imaging, both assessed in 2011-2015, using linear regression and adjusting for demographic and personal characteristics.

RESULTS

Air pollution and noise were associated with language and short-term/working memory and with local atrophy of the fronto-parietal network (FPN), a functional resting-state network associated with these cognitive processes. For example, per 2-μg/m3 PM10, local brain atrophy was more pronounced in the posterior brain regions of the FPN, with a -0.02 [95% confidence interval (CI): -0.04, 0.00] lower lGI. In contrast, in the anterior regions of the FPN, weighted 24-h and nighttime noise were associated with less local brain atrophy [e.g., 0.02 (95% CI: 0.00, 0.04) for 10 dB(A) 24-h noise].

CONCLUSIONS

Air pollution and noise exposures were associated in opposite directions with markers of local atrophy of the FPN in the right brain hemisphere in older adults, suggesting that both chronic air pollution and noise exposure may influence the physiological aging process of the brain. https://doi.org/10.1289/EHP5859.

Road Traffic Noise at the Residence, Annoyance, and Cognitive Function in Elderly Women

The detrimental effects of traffic noise on cognition in children are well documented. Not much is known about the health effects in adults. We investigated the association of residential exposure to road traffic noise and annoyance due to road traffic noise with cognitive function in a cohort of 288 elderly women from the longitudinal Study on the influence of Air pollution on Lung function, Inflammation and Aging (SALIA) in Germany. Residential noise levels-weighted 24-h mean (LDEN) and nighttime noise (LNIGHT)-were modeled for the most exposed facade of dwellings and dichotomized at ≥50 dB(A). Traffic noise annoyance (day and night) was estimated by questionnaire. Cognitive function was assessed using the Consortium to Establish a Registry on Alzheimer's Disease (CERAD-Plus) Neuropsychological Assessment Battery. The modeled noise levels were associated with impaired total cognition and the constructional praxis domain, independently of air pollution. Self-reported noise annoyance was associated with better performance in semantic memory and constructional praxis domains. This finding should be interpreted with caution since we could not control for potential confounding by hearing loss. Noise levels and annoyance were associated, but their health effects seemed mutually independent.

The relationship between naturalistic sleep variation and error monitoring in young adults: An event-related potential (ERP) study

Sleep deprivation studies have highlighted the importance of adequate sleep for optimal daytime functioning. However, there is limited research exploring whether variations in natural sleep patterns produce similar difficulties to those seen in sleep deprivation studies. The aim of the current study was to explore whether naturalistic reductions in sleep duration and/or sleep quality were associated with behavioural and electrophysiological measures of cognitive control. Sixty undergraduate students were asked to wear an actigraph for 7 consecutive nights before completing a hybrid Flanker-Go/NoGo task whilst continuous EEG data were recorded. Participants were assigned to high or low sleep quality and short or long sleep duration groups using the National Sleep Foundation guidelines. Results indicated that individuals who, on average, slept <7 h each night showed inefficiencies in error-monitoring, as reflected by a reduction in amplitude of the error-related negativity (ERN) in comparison to those with longer sleep duration. These findings suggest that natural variations in sleep quantity are associated with atypical error detection.

Poverty's Impact on Children's Executive Functions: Global Considerations

Poverty detrimentally affects child executive function (EF), a subset of cognitive abilities implicated in reading and other achievement outcomes. Consequently, research has focused on understanding explanatory and mediating mechanisms in this association. This research, however, has mainly involved populations from Western, high-income countries. Children from low- and middle-income countries comprise a significant proportion of the world's population and are at additional risk for poor EF as a result of a more disadvantaged context. The present review examines global work on poverty and EF to highlight important cross-national similarities and differences. Findings suggest a global association between poverty and EF and point to cognitive stimulation and environmental enrichment as common mediating variables that may also be moderators and targets for intervention. However, findings also underscore the need to consider the sociocultural context of countries when examining impacts of parenting, schooling, and other metrics. Research and intervention implications are discussed.

Long-Term Air Pollution and Traffic Noise Exposures and Mild Cognitive Impairment in Older Adults: A Cross-Sectional Analysis of the Heinz Nixdorf Recall Study

BACKGROUND

Mild cognitive impairment (MCI) describes the intermediate state between normal cognitive aging and dementia. Adverse effects of air pollution (AP) on cognitive functions have been proposed, but investigations of simultaneous exposure to noise are scarce.

OBJECTIVES

We analyzed the cross-sectional associations of long-term exposure to AP and traffic noise with overall MCI and amnestic (aMCI) and nonamnestic (naMCI) MCI.

METHODS

At the second examination of the population-based Heinz Nixdorf Recall study, cognitive assessment was completed in 4,086 participants who were 50-80 years old. Of these, 592 participants were diagnosed as having MCI (aMCI, n = 309; naMCI, n = 283) according to previously published criteria using five neuropsychological subtests. We assessed long-term residential concentrations for size-fractioned particulate matter (PM) and nitrogen oxides with land use regression, and for traffic noise [weighted 24-hr (LDEN) and night-time (LNIGHT) means]. Logistic regression models adjusted for individual risk factors were calculated to estimate the association of environmental exposures with MCI in single- and two-exposure models.

RESULTS

Most air pollutants and traffic noise were associated with overall MCI and aMCI. For example, an interquartile range increase in PM2.5 and a 10 A-weighted decibel [dB(A)] increase in LDEN were associated with overall MCI as follows [odds ratio (95% confidence interval)]: 1.16 (1.05, 1.27) and 1.40 (1.03, 1.91), respectively, and with aMCI as follows: 1.22 (1.08, 1.38) and 1.53 (1.05, 2.24), respectively. In two-exposure models, AP and noise associations were attenuated [e.g., for aMCI, PM2.5 1.13 (0.98, 1.30) and LDEN 1.46 (1.11, 1.92)].

CONCLUSIONS

Long-term exposures to air pollution and traffic noise were positively associated with MCI, mainly with the amnestic subtype.

CITATION

Tzivian L, Dlugaj M, Winkler A, Weinmayr G, Hennig F, Fuks KB, Vossoughi M, Schikowski T, Weimar C, Erbel R, Jöckel KH, Moebus S, Hoffmann B, on behalf of the Heinz Nixdorf Recall study Investigative Group. 2016. Long-term air pollution and traffic noise exposures and mild cognitive impairment in older adults: a cross-sectional analysis of the Heinz Nixdorf Recall Study. Environ Health Perspect 124:1361-1368; http://dx.doi.org/10.1289/ehp.1509824.

Practice-Related Effects in a Go-Nogo Task

Comparison of an incoming stimulus with a memory template and the inhibition of an irrelevant response representation assumes these are separable processes differently affected by practice. Practice effects were studied in a visual Go-Nogo task which contained stimuli either compatible or incompatible with a response. Eight participants (19–28 years old, M = 23.3, SD = 3.6) performed the task with simultaneous EEG recording every morning during three consecutive weeks except weekends. Short-term, long-term, as well as weekday effects were analyzed. As a short-term effect, the false alarm rate became smaller; this was accompanied by an enhancement of the frontal N2 component of the event-related potential (ERP). As a long-term effect, the shortening of reaction time to incompatible stimuli and increase of the blink rate for Go trials was observed. Within the N2 two subcomponents, the early (N2e) and late (N2l) could be distinguished. N2e and N2l varied differently with the experimental manipulations. First, they showed different effects of stimulus compatibility. Second, the N2e was enhanced with practice irrespective of trial type, while the practice-related increase of the N2l was obtained for Nogo trials only. Third, the practice-related effects on components differed in scalp topography. The results suggest N2e reflects the comparison process and N2l the inhibition of an irrelevant response representation. Both processes improved with practice.

Extreme Environment Effects on Cognitive Functions: A Longitudinal Study in High Altitude in Antarctica

This paper focuses on the impact of long-term Antarctic conditions on cognitive processes. Behavioral responses and event-related potentials were recorded during an auditory distraction task and an attention network paradigm. Participants were members of the over-wintering crew at Concordia Antarctic Research Station. Due to the reduced partial pressure of oxygen this environment caused moderate hypoxia. Beyond the hypoxia, the fluctuation of sunshine duration, isolation and confinement were the main stress factors of this environment. We compared 6 measurement periods completed during the campaign. Behavioral responses and N1/MMN (mismatch negativity), N1, N2, P3, RON (reorientation negativity) event-related potential components have been analyzed. Reaction time decreased in both tasks in response to repeated testing during the course of mission. The alerting effect increased, the inhibition effect decreased and the orienting effect did not change in the ANT task. Contrary to our expectations the N2, P3, RON components related to the attentional functions did not show any significant changes. Changes attributable to early stages of information processing were observed in the ANT task (N1 component) but not in the distraction task (N1/MMN). The reaction time decrements and the N1 amplitude reduction in ANT task could be attributed to sustained effect of practice. We conclude that the Antarctic conditions had no negative impacts on cognitive activity despite the presence of numerous stressors.

Effects of age on cognitive control during semantic categorization

We used event-related potentials (ERPs) to study age effects of perceptual (basic-level) vs. perceptual-semantic (superordinate-level) categorization on cognitive control using the go/nogo paradigm. Twenty-two younger (11 M; 21 ± 2.2 years) and 22 older adults (9 M; 63 ± 5.8 years) completed two visual go/nogo tasks. In the single-car task (SiC) (basic), go/nogo responses were made based on single exemplars of a car (go) and a dog (nogo). In the object animal task (ObA) (superordinate), responses were based on multiple exemplars of objects (go) and animals (nogo). Each task consisted of 200 trials: 160 (80%) 'go' trials that required a response through button pressing and 40 (20%) 'nogo' trials that required inhibition/withholding of a response. ERP data revealed significantly reduced nogo-N2 and nogo-P3 amplitudes in older compared to younger adults, whereas go-N2 and go-P3 amplitudes were comparable in both groups during both categorization tasks. Although the effects of categorization levels on behavioral data and P3 measures were similar in both groups with longer response times, lower accuracy scores, longer P3 latencies, and lower P3 amplitudes in ObA compared to SiC, N2 latency revealed age group differences moderated by the task. Older adults had longer N2 latency for ObA compared to SiC, in contrast, younger adults showed no N2 latency difference between SiC and ObA. Overall, these findings suggest that age differentially affects neural processing related to cognitive control during semantic categorization. Furthermore, in older adults, unlike in younger adults, levels of categorization modulate neural processing related to cognitive control even at the early stages (N2).

Effect of long-term outdoor air pollution and noise on cognitive and psychological functions in adults

It has been hypothesized that air pollution and ambient noise might impact neurocognitive function. Early studies mostly investigated the associations of air pollution and ambient noise exposure with cognitive development in children. More recently, several studies investigating associations with neurocognitive function, mood disorders, and neurodegenerative disease in adult populations were published, yielding inconsistent results. The purpose of this review is to summarize the current evidence on air pollution and noise effects on mental health in adults. We included studies in adult populations (≥18 years old) published in English language in peer-reviewed journals. Fifteen articles related to long-term effects of air pollution and eight articles on long-term effects of ambient noise were extracted. Both exposures were separately shown to be associated with one or several measures of global cognitive function, verbal and nonverbal learning and memory, activities of daily living, depressive symptoms, elevated anxiety, and nuisance. No study considered both exposures simultaneously and few studies investigated progression of neurocognitive decline or psychological factors. The existing evidence generally supports associations of environmental factors with mental health, but does not suffice for an overall conclusion about the independent effect of air pollution and noise. There is a need for studies investigating simultaneously air pollution and noise exposures in association mental health, for longitudinal studies to corroborate findings from cross-sectional analyses, and for parallel toxicological and epidemiological studies to elucidate mechanisms and pathways of action.

Nocturnal air, road, and rail traffic noise and daytime cognitive performance and annoyance

Various studies indicate that at the same noise level and during the daytime, annoyance increases in the order of rail, road, and aircraft noise. The present study investigates if the same ranking can be found for annoyance to nocturnal exposure and next day cognitive performance. Annoyance ratings and performance change during combined noise exposure were also tested. In the laboratory 72 participants were exposed to air, road, or rail traffic noise and all combinations. The number of noise events and LAS,eq were kept constant. Each morning noise annoyance questionnaires and performance tasks were administered. Aircraft noise annoyance ranked first followed by railway and road noise. A possible explanation is the longer duration of aircraft noise events used in this study compared to road and railway noise events. In contrast to road and rail traffic, aircraft noise annoyance was higher after nights with combined exposure. Pooled noise exposure data showed small but significant impairments in reaction times (6 ms) compared to nights without noise. The noise sources did not have a differential impact on performance. Combined exposure to multiple traffic noise sources did not induce stronger impairments than a single noise source. This was reflected also in low workload ratings.

Examining nocturnal railway noise and aircraft noise in the field: sleep, psychomotor performance, and annoyance

BACKGROUND

Traffic noise is interfering during day- and nighttime causing distress and adverse physiological reactions in large parts of the population. Railway noise proved less annoying than aircraft noise in surveys which were the bases for a so called 5 dB railway bonus regarding noise protection in many European countries.

OBJECTIVES

The present field study investigated railway noise-induced awakenings during sleep, nighttime annoyance and the impact on performance the following day. Comparing these results with those from a field study on aircraft noise allowed for a ranking of traffic modes concerning physiological and psychological reactions.

METHODS

33 participants (mean age 36.2 years ± 10.3 (SD); 22 females) living alongside railway tracks around Cologne/Bonn (Germany) were polysomnographically investigated. These data were pooled with data from a field study on aircraft noise (61 subjects) directly comparing the effects of railway and aircraft noise in one random subject effects logistic regression model. Annoyance was rated in the morning evaluating the previous night.

RESULTS

Probability of sleep stage changes to wake/S1 from railway noise increased significantly from 6.5% at 35 dB(A) to 20.5% at 80 dB(A) LAFmax. Rise time of noise events had a significant impact on awakening probability. Nocturnal railway noise led to significantly higher awakening probabilities than aircraft noise, partly explained by the different rise times, whereas the order was inversed for annoyance. Freight train noise compared to passenger train noise proved to have the most impact on awakening probability. Nocturnal railway noise had no effect on psychomotor vigilance.

CONCLUSIONS

Nocturnal freight train noise exposure in Germany was associated with increased awakening probabilities exceeding those for aircraft noise and contrasting the findings of many annoyance surveys and annoyance ratings of our study. During nighttime a bonus for railway noise seems not appropriate.

[Influence of environmental noise on sleep quality and sleeping disorders-implications for health]

Environmental noise is a well-known risk factor influencing sleep-wake behavior and sleep quality. Epidemiologic studies have shown that environmental noise is regarded as the most annoying environmental factor. Noise causes modifications in physiologic and mental functions and may result in health outcomes like elevated blood pressure and ischemic heart disease. Reactions to high sound levels during sleep are decreased sleep intensity, arousals, and increased stress hormone secretion. Effects of poor sleep quality are reduced cognitive performance, tiredness, and psychosomatic symptoms. Long-term consequences of recurrent sleep loss due to environmental noise may be heart disease and increased medication intake. Arousals occur especially due to single noise events and intermittent noise. Laboratory and field studies showed no habituation of physiologic parameters to high sound levels. Sleep is especially sensitive to noise; therefore, sound levels during nighttime should be much lower than during daytime.

How semantic categorization influences inhibitory processing in middle-childhood: an Event Related Potentials study

Throughout middle-childhood, inhibitory processes, which underlie many higher order cognitive tasks, are developing. Little is known about how inhibitory processes change as a task becomes conceptually more difficult during these important years. In adults, as Go/NoGo tasks become more difficult there is a systematic decrease in the P3NoGo response, indicating the use of effective inhibitory strategies (Maguire et al., 2009). This paper investigates the age at which children employ similar inhibitory strategies by studying behavioral and Event Related Potential (ERP) measures of response inhibition for three Go/NoGo tasks. Seventeen 7-8 year-olds and twenty 10-11-year-olds completed three Go/NoGo tasks that differed in the level of categorization necessary to respond. Both age groups displayed slower reaction times as the tasks became more difficult. Further, both groups displayed the predicted Go vs. NoGo P3 amplitude differences in the two simplest tasks, but no significant P3 differences for the most complex task. The reason for this pattern of responses was different in the different age groups. Similar to adults in previous work, the oldest children showed an attenuation of the P3 NoGo response with task difficulty, and no corresponding changes in the Go amplitude. The younger children displayed the opposite pattern, a significant increase in the Go amplitude with task difficulty, and no changes in the NoGo response. These response patterns indicate that efficient inhibitory strategies are developing throughout middle-childhood.

Effects of nocturnal aircraft noise on cognitive performance in the following morning: dose-response relationships in laboratory and field

OBJECTIVE

Nocturnal aircraft noise disturbs sleep and impairs recuperation. We investigated in laboratory and field studies whether noise-induced sleep fragmentation is associated with performance impairments in a psychomotor vigilance task (PVT) and a memory search task.

METHODS

In the laboratory, 112 participants were exposed to aircraft noise during 9 consecutive nights. In the field, 64 participants were examined during 9 consecutive nights in the vicinity of Cologne/Bonn airport. Reaction time, signal detection performance and subjective task load were recorded.

RESULTS

Dose-response relationships showed significant, linear impairments in reaction times. In the laboratory, reaction time in PVT increased with 0.13 ms/dB equivalent noise level (LAeq) plus 0.02 ms/noise event. In the field study, reaction time increased with 0.3 ms/dB LAeq. Participants worked significantly less accurate after nocturnal noise exposure.

CONCLUSION

Influences of LAeq and number of noise events on daytime performance were small but consistent and significant, stressing the potential public health impact of nocturnal noise exposure.

The influence of perceptual and semantic categorization on inhibitory processing as measured by the N2-P3 response

In daily activities, humans must attend and respond to a range of important items and inhibit and not respond to unimportant distractions. Our current understanding of these processes is largely based on perceptually simple stimuli. This study investigates the interaction of conceptual-semantic categorization and inhibitory processing using Event Related Potentials (ERPs). Participants completed three Go-NoGo tasks that increased systematically in the degree of conceptual-semantic information necessary to respond correctly (from single items to categories of objects and animals). Findings indicate that the N2 response reflects inhibitory processing but does not change significantly with task difficulty. The P3 NoGo amplitude, on the other hand, is attenuated by task difficulty. Further, the latency of the peak of the P3 NoGo response elicited by the most difficult task is significantly later than are the peaks detected during performance of the other two tasks. Thus, the level of complexity of conceptual-semantic representations influences inhibitory processing in a systematic way. This inhibition paradigm may be a key for investigating inhibitory dysfunction in patient populations.

To sleep, perchance to enrich learning?

There is evidence that sleep enhances memory and learning. Childhood is a critical period for neurodevelopment, and minor but persistent disruption of sleep may have long-term implications for cognitive performance. Sleep is critical for health and is undervalued both in our 24 h society and in paediatric clinical practice. Paediatricians need to understand the neurodevelopmental consequences of poor quality sleep in children.

Noise Aftereffects and Brain Processes

Abstract. Aftereffects of noise-induced sleep disturbance on executive functions were investigated with motivational traits as mediating variables. Thirty-two healthy young subjects performed a visual Go/Nogo task with simultaneous EEG recording after a quiet night and after 3 nights with railway noise at different noise levels. As motivational traits, the “hope of success” (HS) and “fear of failure” (FF) were assessed. Subjective sleep rating worsened with increased noise level, but, noise-induced sleep disturbances did not affect performance immediately following sleep. However, in the event-related potential (ERP) an attenuation of the N2 and P3 amplitude as well as an increase in N2 latency in Noise conditions were found. Only subjects who scored low in HS showed a reduction of the N2 after Noise, while subjects who scored high in HS did not. The N2 and P3 were larger in high HS than in low HS subjects in Nogo trials only. Similarly, low FF subjects had larger N2 and P3 than high FF subjects in Nogo trials only. The results suggest that achievement motivation modulates executive control and stimulus-response mapping processes as well as their resistance against aftereffects of noise-induced sleep disturbance.