Grade-related changes in event-related potentials (ERPs) in primary school children: Differences between two reading tasks.

Recorded event-related potentials (ERPs) from the left and right temporal and parietal sites during word reading in 39 boys and 30 girls who were followed over 3 yrs, starting at Grade 1. Task 1 required Ss to read repeatedly presented words; Task 2 consisted of a series of different words, with each word being presented only once. All ERP components showed changes in amplitude as a function of grade: P240, N530, the parietal N150, and SW all decreased, whereas the temporal N360 and slow-wave (SW) both increased. Proficient readers showed larger SW and N360 asymmetries and shorter vocal response times than did less proficient readers. A positive relationship was found between reading performance and ERP amplitudes over the left temporal hemisphere at Grades 2 and 3, particularly in the single word reading task. Results are discussed in terms of age-related changes in right and left hemisphere functions involved in learning to read

The development of lateral event-related potentials (ERPs) related to word naming: A four year longitudinal study.

Recorded ERPs from the left and right temporal and parietal sites during a word naming task. Ss were 74 children that were followed over 4 consecutive years starting at kindergarten. ERP waveforms contained a sequence of positive and negative components (N150, P240, N360, N530, and SW). A relationship was found between reading performance and ERP amplitudes over the right parietal hemisphere in young Ss, and over the left temporal hemisphere in older Ss. Proficient readers showed larger (more negative) parietal N530 amplitudes than less proficient readers, especially when stimuli were degraded words. Results are discussed in terms of age-related changes in right and left hemisphere functions involved in early and advanced stages of reading, that might be related to visual word recognition

Hemispheric distribution of ERP components and word naming in preschool children.

Recorded event-related potentials (ERPs) at the left and right temporal and parietal sites of 61 children (aged 5.1-6.2 yrs) during a word-naming task. Ss were divided into fast and slow reading acquisition (RA) groups based on the number of trials they required to learn to read 4 words. Principal component analysis was performed on the average ERP waveforms. Analyses of the factor scores revealed that the P240, N380, and slow wave (SW) components were asymmetrically distributed over the hemispheres. Fast RA was associated with smaller N380 and larger SW activity than slow RA. Multiple regression analyses indicated that only right hemispheric ERP components were significantly associated with rate of RA. Findings are discussed in terms of right hemispheric involvement in early RA

Physical Polyurethane Hydrogels via Charge Shielding through Acids or Salts

Physical hydrogels with tunable stress‐relaxation and excellent stress recovery are formed from anionic polyurethanes via addition of acids, monovalent salts, or divalent salts. Gel properties can be widely adjusted through pH, salt valence, salt concentration, and monomer composition. We propose and investigate a novel gelation mechanism based on a colloidal system interacting through charge repulsion and chrage shielding, allowing a broad use of the material, from acidic (pH 4–5.5) to pH‐neutral hydrogels with Young's moduli ranging from 10 to 140 kPa

Heavy alcohol use, rather than alcohol dependence, is associated with dysregulation of the hypothalamic-pituitary-adrenal axis and the autonomic nervous system

BACKGROUND: Heavy alcohol use as well as alcohol dependence (AD) have been associated with dysregulation of the hypothalamic-pituitary-adrenal (HPA)-axis and the autonomic nervous system (ANS). However, the relative contribution of alcohol use and AD is unclear. METHODS: Baseline data were derived from 2947 persons of the Netherlands Study of Depression and Anxiety (NESDA), including non-drinkers (n=498), moderate drinkers (n=2112) and heavy drinkers (n=337). We also distinguished between persons with no lifetime DSM-IV AD (n=2496), remitted AD (> 1 year; n = 243), and current AD (≤ 1 year; n=208). ANS measures included ECG-based heart rate (HR), respiratory sinus arrhythmia (RSA, high RSA reflecting high cardiac parasympathetic control) and pre-ejection period (PEP, high PEP reflecting low cardiac sympathetic control). HPA-axis measures included the cortisol awakening response (area under the curve with respect to the ground [AUCg] and increase [AUCi]), evening cortisol and a 0.5mg dexamethasone suppression test, all measured in saliva. RESULTS: Heavy drinkers showed higher basal cortisol levels (AUCg: p=.02; evening cortisol: p=.006) and increased cardiac sympathetic control (higher HR: p=.04; lower PEP: p=.04) compared to moderate drinkers. Persons with current or remitted AD did not differ from persons without lifetime AD on any of the HPA-axis or ANS indicators (all p>.33). Similar patterns of HPA-axis and ANS activity across alcohol use groups were found in persons with and without lifetime AD. CONCLUSIONS: Our findings suggest that current heavy alcohol use, rather than current or remitted AD, is associated with hyperactivity of the HPA-axis and increased cardiac sympathetic control