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This paper studied whether abnormal P3 amplitudes in PDD are a corollary of abnormalities in ERP components related to selective attention in visual and auditory tasks. Furthermore, this study sought to clarify possible age differences in such abnormalities. Children with PDD showed smaller P3 amplitudes than controls, but no abnormalities in selective attention. Adolescents with PDD showed abnormal selective attention, as reflected by larger auditory Processing Negativity (PN) and visual N2b, but no P3 abnormalities. Dipole localizations revealed that the locations of PN generators in subjects with PDD differed from controls. It was concluded that the abnormalities in selective attention in adolescents with PDD have a normalizing effect on P3, and possibly act as a compensatory process.

This study sought to investigate whether the abnormally small P3 amplitudes observed in pervasive developmental disorder (PDD) are related to differences in processing capacity. PDD children and adolescents and their control groups participated in the study. Visual probe stimuli were presented during an auditory task with two levels of difficulty. Event-related potentials (ERP) were measured from 62 electrodes during task performance. All groups showed amplitude increases to auditory stimuli with increasing task load. Controls showed expected smaller P3 amplitudes to visual probes, whereas PDD subjects did not. The results suggest that autistic subjects show abnormal capacity allocation. Some of these abnormalities may dissolve over time, while others remain into adolescence.

The brain plays an important regulatory role in directing energy homeostasis and eating behavior. The increased ingestion of sugars and sweeteners over the last decades makes investigating the effects of these substances on the regulatory function of the brain of particular interest. We investigated whole brain functional response to the ingestion of nutrient shakes sweetened with either the nutritive natural sugars glucose and fructose, the low- nutritive natural sugar replacement allulose or the non-nutritive artificial sweetener sucralose. Twenty healthy, normal weight, adult males underwent functional MRI on four separate visits. In a double-blind randomized study setup, participants received shakes sweetened with glucose, fructose, allulose or sucralose. Resting state functional MRI was performed before and after ingestion. Changes in Blood Oxygen Level Dependent (BOLD) signal, functional network connectivity and voxel based connectivity by Eigenvector Centrality Mapping (ECM) were measured. Glucose and fructose led to significant decreased BOLD signal in the cingulate cortex, insula and the basal ganglia. Glucose led to a significant increase in eigen vector centrality throughout the brain and a significant decrease in eigen vector centrality in the midbrain. Sucralose and allulose had no effect on BOLD signal or network connectivity but sucralose did lead to a significant increase in eigen vector centrality values in the cingulate cortex, central gyri and temporal lobe. Taken together our findings show that even in a shake containing fat and protein, the type of sweetener can affect brain responses and might thus affect reward and satiety responses and feeding behavior. The sweet taste without the corresponding energy content of the non-nutritive sweeteners appeared to have only small effects on the brain. Indicating that the while ingestion of nutritive sugars could have a strong effect on feeding behavior, both in a satiety aspect as well as rewarding aspects, non-nutritive sweeteners appear to not have these effects. This study is registered at clinicaltrials.gov under number NCT02745730. [ABSTRACT FROM AUTHOR]

Background: Excessive consumption of sugar-sweetened beverages (SSBs) has been associated with obesity and related diseases. SSBs are often consumed cold, and both the energy content and temperature might influence the consumption behavior for SSBs. Objective: The main aim of this study was to elucidate whether consumption temperature and energy (i.e., glucose) content modulate homeostatic (hypothalamus) and reward [ventral tegmental area (VTA)] responses. Design: Sixteen healthy men participated in our study [aged 18-25 y; body mass index (kg/m²): 20-23]. High-resolution functional magnetic resonance imaging data were collected after ingestion of 4 different study stimuli: plain tap water at room temperature (22°C), plain tap water at 0°C, a glucose-containing beverage (75 g glucose dissolved in 300 mL water) at 22°C, and a similar glucose drink at 0°C. Blood oxygen level-dependent (BOLD) changes from baseline (7 min preingestion) were analyzed over time in the hypothalamus and VTA for individual stimulus effects and for effects between stimuli. Results: In the hypothalamus, water at 22°C led to a significantly increased BOLD response; all other stimuli resulted in a direct, significant decrease in BOLD response compared with baseline. In the VTA, a significantly decreased BOLD response compared with baselinewas found after the ingestion of stimuli containing glucose at 0°C and 22°C. These responses were not significantly modulated by consumption temperature. The consumption of plain water did not have a significant VTA BOLD effect. Conclusions: Our data show that glucose at 22°C, glucose at 0°C, and water at 0°C lowered hypothalamic activity, which is associated with increased satiation. On the contrary, the consumption of water at room temperature increased activity. All stimuli led to a similar VTA response, which suggests that all drinks elicited a similar hedonic response. Our results indicate that, in addition to glucose, the low temperature at which SSBs are often consumed also leads to a response from the hypothalamus and might strengthen the response of the VTA. This trial was registered at www.clinicaltrials.gov as NCT03181217. [ABSTRACT FROM AUTHOR]

Visual–tactile carry-over effects of global/local processing (attention to the whole, versus the details) have been reported under active touch conditions. We investigated whether carry-over effects of global/local processing also occur for passive touch and whether global/local processing has differential effects on affective and discriminative aspects of touch. Participants completed two tactile tasks involving pleasantness rating and discrimination of a set of tactile vibrations before and after completing a version of the Navon task that encouraged a focus on the global (n = 30), local (n = 30), or both (n = 30) features of a series of visual stimuli. In line with previous research suggesting a link between global processing and positive emotion, global processing increased pleasantness ratings of high-frequency (but not low-frequency) tactile vibrations. Local processing did not improve the ability to discriminate between vibrations of different frequencies, however. There was some evidence of a tactile–visual carry-over effect; prior local processing of tactile vibrations reduced global precedence during the Navon task in the control group. We have shown carry-over effects of global versus local processing on passive touch perception. These findings provide further evidence suggesting that a common perceptual mechanism determines processing level across modalities and show for the first time that prior global processing affects the pleasantness of touch. [ABSTRACT FROM PUBLISHER]

Attention deficit/hyperactivity disorder (ADHD) is one of the most common child psychiatric disorders, and is often treated with stimulant medication. Nonpharmacological treatments include dietary supplementation with omega-3 fatty acids, although their effectiveness remains to be shown conclusively. In this study, we investigated the effects of dietary omega-3 fatty acid supplementation on ADHD symptoms and cognitive control in young boys with and without ADHD. A total of 40 boys with ADHD, aged 8-14 years, and 39 matched, typically developing controls participated in a 16-week double-blind randomized placebo-controlled trial. Participants consumed 10 g of margarine daily, enriched with either 650 mg of eicosapentaenoic acid (EPA)/docosahexaenoic acid (DHA) each or placebo. Baseline and follow-up assessments addressed ADHD symptoms, fMRI of cognitive control, urine homovanillic acid, and cheek cell phospholipid sampling. EPA/DHA supplementation improved parent-rated attention in both children with ADHD and typically developing children. Phospholipid DHA level at follow-up was higher for children receiving EPA/DHA supplements than placebo. There was no effect of EPA/DHA supplementation on cognitive control or on fMRI measures of brain activity. This study shows that dietary supplementation with omega-3 fatty acids reduces symptoms of ADHD, both for individuals with ADHD and typically developing children. This effect does not appear to be mediated by cognitive control systems in the brain, as no effect of supplementation was found here. Nonetheless, this study offers support that omega-3 supplementation may be an effective augmentation for pharmacological treatments of ADHD (NCT01554462: The Effects of EPA/DHA Supplementation on Cognitive Control in Children with ADHD; http://clinicaltrials.gov/show/NCT01554462). [ABSTRACT FROM AUTHOR]

Some people perceive themselves to look more, or less attractive than they are in reality. We investigated the role of emotions in enhancement and derogation effects; specifically, whether the propensity to experience positive and negative emotions affects how healthy we perceive our own face to look and how we judge ourselves against others. A psychophysical method was used to measure healthiness of self-image and social comparisons of healthiness. Participants who self-reported high positive (N = 20) or negative affectivity (N = 20) judged themselves against healthy (red-tinged) and unhealthy looking (green-tinged) versions of their own and stranger’s faces. An adaptive staircase procedure was used to measure perceptual thresholds. Participants high in positive affectivity were un-biased in their face health judgement. Participants high in negative affectivity on the other hand, judged themselves as equivalent to less healthy looking versions of their own face and a stranger’s face. Affective traits modulated self-image and social comparisons of healthiness. Face health judgement was also related to physical symptom perception and self-esteem; high physical symptom reports were associated a less healthy self-image and high self-reported (but not implicit) self-esteem was associated with more favourable social comparisons of healthiness. Subject to further validation, our novel face health judgement task could have utility as a perceptual measure of well-being. We are currently investigating whether face health judgement is sensitive to laboratory manipulations of mood. [ABSTRACT FROM AUTHOR]

This study reports an examination of the internal clock model, according to which subjective time duration is influenced by attention and arousal state. In a time production task, we examine the hypothesis that an arousing odor and an upright body posture affect perceived duration. The experimental task was performed while participants were exposed to an odor and either sitting upright (arousing condition) or lying down in a relaxing chair (relaxing condition). They were allocated to one of three experimental odor conditions: rosemary (arousing condition), peppermint (relaxing condition), and no odor (control condition). The predicted effects of the odors were not borne out by the results. Self-reported arousal (SRA) and pleasure (PL) states were measured before, during (after each body posture condition) and postexperimentally. Heart rate (HR) and skin conductance were measured before and during the experiment. As expected, odor had an effect on perceived duration. When participants were exposed to rosemary odor, they produced significantly shorter time intervals than in the no odor condition. This effect, however, could not be explained by increased arousal. There was no effect of body posture on perceived duration, even though body posture did induce arousal. The results do not support the proposed arousal mechanism of the internal clock model. [ABSTRACT FROM AUTHOR]

Both theoretical models and functional imaging studies implicate the involvement of emotions within the delay discounting process. However, defining this role has been difficult to establish with neuroimaging techniques given the automaticity of emotional responses. To address this, the current study examined electrophysiological correlates involved in the detection and evaluation of immediate and delayed monetary outcomes. Our results showed that modulation of both early and later ERP components previously associated with affective stimuli processing are sensitive to the signalling of delayed rewards. Together with behavioural reaction times that favoured immediacy, we demonstrated, for the first time, that time delays modify the incentive value of monetary rewards via mechanisms of emotional bias and selective visual attention. Furthermore, our data are consistent with the hypothesis that delayed and thus intangible rewards are perceived less saliently, and rely on emotion as a common currency within decision making. This study provides a new approach to delay discounting and highlights a potential novel route through which delay discounting may be investigated. [ABSTRACT FROM AUTHOR]

Introduction and objectives: Previous studies have shown that children with attention deficit hyperactivity disorder (ADHD) may benefit from dietary supplementation with omega-3 fatty acids (EPA and DHA). The objective of this study is to determine the effects of EPA/DHA supplementation on cognitive control and associated brain activity in prefrontal and striatal areas. Methods: Boys with ADHD (N = 40) and typically developing boys (N = 40), aged 8–12 years, participate in a pre- and post treatment fMRI session. Cognitive control will be assessed using a go/no-go paradigm. During the intervention period children are randomised to receive a supplement containing EPA/DHA or a placebo product on a daily basis. Symptoms of ADHD will be assessed on a monthly basis. Cheek cell and urine samples are collected for physiological analyses. Results: At this point we are in the process of data acquisition and researchers are blind to intervention group. Preliminary analysis of the baseline scans to date (N = 4 typically developing, 5 ADHD) shows decreases in activation for subjects in ADHD in cognitive control regions, similar to other reports. [ABSTRACT FROM AUTHOR]