Hilde Gundersen

Separating the effects of alcohol and expectancy on brain activation: An fMRI working memory study ☆

The aim of this study was to use BOLD fMRI to evaluate the effect of alcohol intoxication on neuronal activation, when controlling for expectancy. Behavioural studies have shown that both alcohol intoxication and expectancy affect cognition, mood and behaviour. However, previous neuroimaging studies have not separated the effects of alcohol intoxication from the possible confounding effects of expectancy. Forty-five healthy male participants participated in the study. A balanced placebo design with four groups was used together with a working memory paradigm. Half of the participants consumed a soft-drink before the MR scanning session (half of them were correctly informed about the content of their drink, and half were incorrectly informed that they consumed an alcoholic beverage), and the other half consumed an alcoholic beverage before the MR scanning session (half of them were correctly informed about the content of their drink, and half were incorrectly informed that they consumed a soft-drink). A blood alcohol concentration (BAC) of 0.08% was used as the alcohol intoxication level. The most conspicuous result was that alcohol intoxication decreased neuronal activation especially in the dorsal anterior cingulate cortex (dACC) and in prefrontal areas, while expectancy increased neuronal activation in the same areas. This study shows that alcohol intoxication and expectancy have opposite effects on neuronal activation. The present results could have implications for pharmacological imaging studies.

fMRI: blood oxygen level-dependent activation during a working memory-selective attention task in children born extremely preterm

Background:Extremely preterm (EPT)/extremely low-birth-weight (ELBW) children attaining school age and adolescence often have problems with executive functions such as working memory and selective attention. Our aim was to investigate a hypothesized difference in blood oxygen level–dependent (BOLD) activation during a selective attention–working memory task in EPT/ELBW children as compared with term-born controls.Methods:A regional cohort of 28 EPT/ELBW children and 28 term-born controls underwent functional magnetic resonance imaging (fMRI) scanning at 11 y of age while performing a combined Stroop n-back task. Group differences in BOLD activation were analyzed with Statistical Parametric Mapping 8 analysis software package, and reaction times (RTs) and response accuracy (RA) were compared in a multifactorial ANOVA test.Results:The BOLD activation pattern in the preterm group involved the same areas (cingulate, prefrontal, and parietal cortexes), but all areas displayed significantly less activation than those in the control group, particularly when the cognitive load was increased. The RA results corresponded with the activation data in that the preterm group had significantly fewer correct responses. No group difference was found regarding RTs.Conclusion:Children born EPT/ELBW displayed reduced working memory and selective attention capacity as compared with term-born controls. These impairments had neuronal correlates with reduced BOLD activation in areas responsible for online stimulus monitoring, working memory, and cognitive control.

The Effects of Alcohol Intoxication on Neuronal Activation at Different Levels of Cognitive Load

The aim of this study was to investigate how alcohol intoxication at two blood alcohol concentrations (BAC) affected neuronal activation during increasing levels of cognitive load. For this purpose we used functional magnetic resonance imaging (fMRI) together with a working memory n-back paradigm with three levels of difficulty. Twenty-five healthy male participants were scanned twice on two separate days. Participants in the control group (N=13) were scanned after drinking a soft-drink at both scanning sessions, while participants in the alcohol group (N=12) were scanned once after drinking an alcoholic beverage resulting in a BAC of 0.02%, and once after drinking an alcoholic beverage resulting in a BAC of 0.08%. A decrease in neuronal activation was seen in the dorsal anterior cingulate cortex (dACC) and in the cerebellum in the alcohol group at the BAC of 0.08% when the participants performed the most demanding task. The dACC is important in cognitive control, working memory, response inhibition, decision making and in error monitoring. The results have revealed that the effect of alcohol intoxication on brain activity is dependent on BAC and of cognitive load.

Traffic Density in Area of Residence is Associated With Health-Related Quality of Life in Women, The Community-Based Hordaland Health Study

ABSTRACT Vehicle traffic is increasing worldwide, and this is a major concern because traffic-related air pollution and noise may influence health. The aim of this study was to evaluate whether health-related quality of life (HRQoL) is associated with vehicle traffic density in area of residence. A total of 16,410 individuals, 40 to 45 years old, were asked to participate in this study (response rate: 55% for men, 66% for women). Using the 12-Item Short Form Health Survey (SF-12) questionnaire, both physical and mental HRQoL were investigated. Multiple linear regression analyses showed that women living in areas with high traffic density had significantly poorer physical HRQoL than women living in areas with moderate or low vehicle traffic density. There were no similar findings among men. Mental HRQoL was not associated with vehicle traffic density in the area of residence, neither for women nor for men. There is an association between high vehicle traffic density in residential area and reduced HRQoL in women.

Speech Lateralization and Attention/Executive Functions in a Finnish Family With Specific Language Impairment (SLI)

Hemisphere lateralization for speech perception was investigated in a Finnish family with specific language impairment. We used dichotic presentations of consonant–vowel (CV) syllables, consisting of the six stop-consonants paired with the vowel /a/, under three different attentional instructions. The dichotic listening technique means that two different speech stimuli are presented simultaneously, one in each ear. Left hemisphere dominance for speech perception is assessed from a preference for the right ear stimulus. Response accuracy was compared in five members, over three generations, of a family with SLI with 5 healthy control subjects. The dichotic listening task was performed under three different instructions, to attend only to the right ear stimulus, to attend only to the left ear stimulus, or with no instruction about attention. The subjects indicated orally which of the six CV-syllables they heard on each trial. There were 36 dichotic presentations of the CV-syllables for each instruction. The CV-syllables were played from a CD with digitized stimuli. The results showed no difference between the groups during the no instruction condition, indicating normal speech lateralization in the SLI group. However, the SLI group was deficient in modifying the ear advantage through focused attention to the left ear, thus indicating an attentional/executive deficit in addition to a deficit in left hemisphere lateralization. It is concluded that individuals with specific language impairment may have a cognitive deficit related to attention in addition to a language processing deficit related to left hemisphere function.

Alcohol-Induced Changes in Cerebral Blood Flow and Cerebral Blood Volume in Social Drinkers

AIMS Although it is known that alcohol has vasoactive properties, previous studies have not investigated the relationship between cerebral blood flow (CBF) and cerebral blood volume (CBV) after alcohol consumption. The aim of this study was to investigate effects of alcohol on CBF and CBV, both globally and regionally, in social drinkers. METHODS The method of choice was dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI). Eight males were scanned twice on two separate days; once after consumption of alcohol (blood-alcohol concentration (BAC) of 0.08%) and once sober. RESULTS The results showed an average increase of CBF after alcohol consumption, both in grey matter (GM) and in white matter (WM), with a CBF(BAC of 0.08%)/CBF(baseline) ratio of 1.2. Regional increases in CBF were seen in areas close to where the large brain-feeding blood vessels enter the brain, in the thalamus region and in the frontal brain regions. The lowest CBF changes were seen in the occipital brain regions. There was also an increase in CBV after alcohol consumption, in particular across WM regions. CONCLUSION In conclusion, a BAC of 0.08% causes both an average increase in global and regional CBF. There was stronger correlation between alcohol-induced changes in CBF and CBV in WM than in GM, suggesting the vasculature in the WM to be relatively more affected than the GM. Simultaneous measurements of CBF and CBV after acute alcohol intoxication in social drinkers are important in basic human neuroscience research to elucidate and understand brain physiology in the presence of exogenous neuro-pharmaceutical manipulations.

Noise exposure and cognitive performance: A study on personnel on board Royal Norwegian Navy vessels

Prior research shows that work on board vessels of the Royal Norwegian Navy (RNoN) is associated with noise exposure levels above recommended standards. Further, noise exposure has been found to impair cognitive performance in environmental, occupational, and experimental settings, although prior research in naval and maritime settings is sparse. The aim of this study was to evaluate cognitive performance after exposure to noise among personnel working on board vessels in the RNoN. Altogether 87 Navy personnel (80 men, 7 women; 31 ± 9 years) from 24 RNoN vessels were included. Noise exposure was recorded by personal noise dosimeters at a minimum of 4 h prior to testing, and categorized into 4 groups for the analysis: <72.6 dB(A), 72.6-77.0 dB(A), 77.1-85.2 dB(A), and >85.2 dB(A). The participants performed a visual attention test based on the Posner cue-target paradigm. Multivariable general linear model (GLM) analyses were performed to analyze whether noise exposure was associated with response time (RT) when adjusting for the covariates age, alertness, workload, noise exposure in test location, sleep the night before testing, use of hearing protection device (HPD), and percentage of errors. When adjusting for covariates, RT was significantly increased among personnel exposed to >85.2 dB(A) and 77.1-85.2 dB(A) compared to personnel exposed to <72.6 dB(A).

Low Traffic and Respiratory Symptoms Among Smoking Females: The Hordaland Health Study

ABSTRACT The main aim of this study was to evaluate the prevalence of respiratory symptoms among men and women separately in areas with relatively low traffic density. Data on respiratory symptoms were collected from questionnaires in the Hordaland Health Study. A total of 16,412 individuals, 40 to 45 years, were asked to participate (response rate: 55% for men and 66% for women). Women residing in areas with the highest traffic density had increased prevalence of daily cough (18% vs 8.2%, p < .01), of cough with sputum (8.8% vs 2.8%, p < .01), and of chronic cough (11% vs 4.7%, p < .01) compared with women residing in areas with lower traffic density. The differences were most pronounced for smoking females. There were no similar findings among men. In conclusion, even within areas with relatively low environmental air pollution, respiratory symptoms was related to traffic density among smoking females.

Biomarker of chronic cadmium exposure in a population residing in the vicinity of a zinc producing plant.

Measurements of cadmium (Cd) in air, soil and moss have shown elevated concentrations in residential areas close to a zinc smelter in Norway. This study aimed to evaluate whether men and women residing in the area with elevated Cd concentrations in air and soil had increased levels of Cd and microproteins in urine. An invitation to participate was mailed to 200 persons residing close to the zinc smelter and to 200 controls from an area more than 4 km away from the smelter. They were asked to complete a questionnaire, and to deliver a urine sample for analysis of cadmium (CdU), mercury (HgU), lead (PbU) and α1-microglobulin (ProteinHC). Two hundred and six participants (response rate 52%), between 19 and 88 years of age, were included. Results were analysed by multiple-adjusted linear and logistic regression. CdU was not significantly different between individuals in the two residence areas. Only ten individuals had CdU concentrations exceeding European Food Safety Authority (EFSA) critical value of 1 μg/g creatinine, whereas 35 persons (22% of the women vs. 11% of the men) had CdU concentrations higher than 0.66 μg/g creatinine, which EU suggested to be sufficiently protective for the general population. Smoking was the predominant contributing factor to values of elevated CdU. There was a tendency of higher CdU, although not statistically significant, amongst people regularly consuming fruit, berries and vegetables grown in their own garden near the smelter area. Home address in the polluted area was not a significant determinant. There was a positive correlation between CdU and ProteinHC in urine, but no significant difference was found for ProteinHC between residents from polluted area and controls. In spite of demonstrated industrial emissions of cadmium, the results do not indicate elevated cadmium exposure or kidney damage in the polluted area compared to the control area.

A Comparative Study of Sleep and Mood Between Young Elite Athletes and Age-Matched Controls

BACKGROUND Sleep and mood have seldom been compared between elite athletes and nonelite athletes, although potential differences suggest that physical activity may affect these parameters. This study aims to explore whether adolescent elite athletes differ from controls in terms of sleep, positive affect (PA) and negative affect (NA). METHODS Forty-eight elite athletes and 26 controls participating in organized and nonorganized sport completed a questionnaire, and a 7-day sleep diary. RESULTS On school days, the athletes and the controls who participated in organized and nonorganized sport differed in bedtime (22:46, 23:14, 23:42, P < .01), sleep onset (23:03, 23:27, 00:12, P < .01), and total sleep time (7:52, 8:00, 6:50, P < 01). During weekend, the athletes, the controls who participated in organized and nonorganized sport differed in bedtime (23:30, 00:04, 00:49, P < .01), sleep onset (23.42, 00:18, 01:13, P < .01), rise time (9:15, 9:47, 10:55, P < .01), sleep efficiency (95.0%, 94.2%, 90.0%, P < 05), and sleep onset latency (11.8, 18.0, 28.0 minutes, P < .01). Furthermore, the athletes reported less social jetlag (0:53) and higher score for PA (34.3) compared with the controls who participated in nonorganized sport (jetlag: 1:25, P < .05, PA: 29.8, P < .05). CONCLUSIONS An almost dose-response association was found between weekly training hours, sleep, social jetlag and mood in adolescents.