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Differential effects of blue- and red-enriched light on attention and sleep have been primarily described in adults. In our cross-over study in typically developing adolescents (11-17 years old), we found attention enhancing effects of blue- compared to red-enriched light in the morning (high intensity of ca. 1000 lx, short duration:1 h) in two of three attention tasks: e.g. better performance in math tests and reduced reaction time variability in a computerized attention test. In our pilot study, actigraphy measures of sleep indicated slight benefits for red- compared to blue-enriched light in the evening: tendencies toward a lower number of phases with movement activity after sleep onset in the complete sample and shorter sleep onset latency in a subgroup with later evening exposure times. These findings point to the relevance of light concepts regarding attention and sleep in typically developing adolescents. Such concepts should be developed and tested further in attention demanding contexts (at school) and for therapeutic purposes in adolescents with impaired attention or impaired circadian rhythms.

Studies have shown that child development is negatively affected by prenatal depression. A dysregulated hypothalamic-pituitary-adrenal axis in the pregnant woman, passed to the fetus, is one discussed key mechanism. Studies, investigating primary-school age children, have found effects on antisocial behavior. Effects on internalizing symptoms were not found, but the analysis did not distinguish between anxiety and depression symptoms. Additionally, until now, no objective test data operationalizing social-emotional competencies have been included. The present study examined: 1.Whether the effects on child externalizing symptoms could be replicated; 2. If there are specific effects on child internalizing symptoms, separated for anxiety and depression; and 3. Are child clinical symptoms reflected in reductions in social-emotional competencies. A sample of 61 prenatally depressed and 143 prenatally not-depressed women and their 6–9 year old children were compared, controlling for key confounders in both the perinatal period and in middle childhood. Children of prenatally depressed mothers had more antisocial behavior and depression symptoms reported by their mothers. The prediction of antisocial behavior scores tended to be more significant for boys than for girls. Child anxiety symptoms were primarily explained by current maternal depressive symptoms. Children of prenatally depressed mothers also showed a reduction in social-emotional competencies, specifically regarding the ability to interpret complex social situations. This study showed that, even in a non-clinical sample, there are distinct effects of prenatal depression on child externalizing and internalizing symptoms which are accompanied by reductions in specific social-emotional competencies. These results emphasize that treatment for depressed pregnant women and/or early support for affected families is worthwhile. Additional work is required to identify the underlying biological mechanisms.

Background Transcranial random noise stimulation (tRNS) is an innovative technique of non-invasive electrical stimulation. tRNS over the parietal cortex has improved cognitive function in healthy controls and, applied to the auditory cortex, tRNS has shown beneficial effects on tinnitus. Objective/hypothesis Here we aimed to investigate the effects of tRNS over the auditory cortex on resting state and evoked activity in healthy subjects. Methods We used EEG to measure tRNS induced changes in resting state activity and in auditory steady state responses (ASSRs). Stimuli were 1000 Hz carrier frequency tones, amplitude modulated at 20 Hz and 40 Hz and applied in randomized order. Fourteen subjects participated in a placebo-controlled randomized design study; each received 20 min of tRNS applied over auditory cortices with 2 mA, with a one week interval between real and sham stimulation. Results We found a significant increase in the ASSR in response to 40 Hz frequency modulated tone and a non-significant trend toward an increase in mean theta band power and variability of the theta band power for the resting state data. Conclusions Our finding of tRNS induced increased excitability in the auditory cortex parallels previous findings of tRNS effects on motor cortex excitability and is in line with current concepts of tRNS mechanisms such as increase of stochastic resonance.

People with developmental dyslexia have been shown to have both behavioral and physiological differences when compared with healthy individuals, specifically when looking at the parietal cortex. Reading and writing deficits are well documented, but other cognitive deficits in dyslexia are not as well known. To investigate spatial deficits in children with developmental dyslexia we used a mental rotation test with three types of stimuli (letters, animals, and objects that look like letters) while simultaneously recording electroencephalographs. Behaviorally, it was found that dyslexic children took more time than nondyslexic children to solve the 'letter' and 'object' stimuli and that the dyslexic children had a slower mental rotation speed when solving 'letter' stimuli. The electroencephalographic data demonstrated more negative amplitude modulations for the dyslexic group in the left hemisphere at the time epochs: 200-300, 600-700, 700-800, 800-900, and 900-1000 ms and in the right hemisphere for the time epoch 600-700 and 900-100 ms. In addition, hemispheric group differences were found on the basis of stimuli for the time epoch 600-700 ms in which the processing of letters was lateralized to the left hemisphere for both groups, but the object stimuli was lateralized to the left for nondyslexic and to the right for dyslexic children. These differences support the idea that the behavioral differences found between dyslexic and nondyslexic children may be because of both differences in the early processing of the stimuli and perhaps in the mental rotation itself.

Neurofeedback (NF) is increasingly used as a therapy for attention-deficit/hyperactivity disorder (ADHD), however behavioral improvements require 20 plus training sessions. More economic evaluation strategies are needed to test methodological optimizations and mechanisms of action. In healthy adults, neuroplastic effects have been demonstrated directly after a single session of NF training. The aim of our study was to test the feasibility of short-term theta/beta NF in children with ADHD and to learn more about the mechanisms underlying this protocol. Children with ADHD conducted two theta/beta NF sessions. In the first half of the sessions, three NF trials (puzzles as feedback animations) were run with pre- and post-reading and picture search tasks. A significant decrease of the theta/beta ratio (TBR), driven by a decrease of theta activity, was found in the NF trials of the second session demonstrating rapid and successful neuroregulation by children with ADHD. For pre-post comparisons, children were split into good vs. poor regulator groups based on the slope of their TBR over the NF trials. For the reading task, significant EEG changes were seen for the theta band from pre- to post-NF depending on individual neuroregulation ability. This neuroplastic effect was not restricted to the feedback electrode Cz, but appeared as a generalized pattern, maximal over midline and right-hemisphere electrodes. Our findings indicate that short-term NF may be a valuable and economical tool to study the neuroplastic mechanisms of targeted NF protocols in clinical disorders, such as theta/beta training in children with ADHD.