Neuroelectric indices of attention are related to academic skills in preschool-aged children.

PURPOSE: This study assessed the relationship between neuroelectric indices of attention and inhibition and academic skills in children 4-6 years-old. We hypothesized that modulation of the P3 and N2 components would be related to academic skills. METHODS: Participants (N = 27, 16 female) completed The Woodcock Johnson Early Cognitive and Academic Development Test to assess general intellectual abilities (GIA) and early academic skills (EAS). Electroencephalography was recorded during an auditory oddball task to elicit P3 and N2 components. Two-step linear regressions including age, sex, income, and GIA assessed relationships between P3 and N2 modulations and EAS. RESULTS: P3 peak amplitude (R2=0.765, ß=0.379, p = 0.030) and N2 mean (R2=0.759, ß=0.302, p = 0.039) and peak (R2=0.759, ß=0.303, p = 0.038) amplitude modulation were positively related to EAS. CONCLUSION: Upregulation of P3 and N2 components was associated with EAS independent of GIA. Therefore, neuroelectric assessments of attention and inhibition may a biomarker of academic achievement in early childhood.

Weight status impacts children's incidental statistical learning.

The expanding literature investigating the cognitive effects of childhood weight status has not included examinations of incidental statistical learning, the process by which children unintentionally acquire knowledge about patterns in their environments, despite evidence that it underlies many higher-level information processing capabilities. In the present study, we measured event-related potentials (ERPs) while school-aged participants completed a variation of an oddball task in which stimuli predicted the appearance of a target. Children were asked to respond to the target but were not given any information about the existence of predictive dependencies. We found that children with a healthy weight status had larger P3 amplitudes in response to the predictors that were most meaningful in completing the task, a finding that may suggest optimized learning mechanisms influenced by weight status. These findings offer an important first step to understanding how healthy lifestyle factors may influence incidental statistical learning.

Neuroelectric indices of motor response preparation are selectively associated with physical activity among adults with obesity.

Previous work has demonstrated that physical activity and weight status are associated with attentional inhibition (indexed with the P3 component of event-related potentials). However, there is limited knowledge on the neural underpinnings of motor response planning and activation. This study investigated the effect of weight status on relationships between moderate-to-vigorous physical activity (MVPA) and the lateralized readiness potential (LRP), a neuroelectric index of motor response planning and activation. Adults (N = 165 [98 females]) wore ActiGraph wGT3X+ accelerometers to measure physical activity. Behavioral outcomes were recorded during the modified Eriksen Flanker task to assess attentional inhibition. EEG recordings were taken to elucidate response- (LRP-R) and stimulus-locked (LRP-S) LRPs, and P3. Participants were separated into groups based on the BMI cutoff of 30 kg/m2 (i.e., non-obese [n = 88], obese [n = 77]). Independent t-tests and ANCOVA were conducted to determine differences between groups. Regression analyses within each group were conducted to determine relationships between MVPA and LRP and P3 amplitude and latencies. There was no difference in MVPA between weight groups after adjustment for age and sex, although the non-obese group had significantly higher incongruent accuracy (p = 0.007). Only in the obese group, MVPA was positively associated with LRP-R incongruent (ß = 0.014, p = 0.029) and LRP-S congruent (ß = 0.013, p = 0.008) amplitude, and inversely associated with LRP-S incongruent (ß = -0.488, p = 0.017) and P3 congruent (ß = 0.013, p = 0.008) fractional area latency. MVPA was associated with pre-motor planning and activation only among persons with obesity. Future work should study the impact of physical activity on neuroelectric indices of motor responses in people with obesity.

Dietary lutein plus zeaxanthin and choline intake is interactively associated with cognitive flexibility in middle-adulthood in adults with overweight and obesity.

BACKGROUND: The xanthophyll carotenoids lutein+zeaxanthin and the dietary component choline have been linked to benefits in cognition. However, knowledge on the interactive influence of these dietary components on cognitive function is sparse. DESIGN: 80 middle-aged adults with overweight and obesity (Body Mass Index: (BMI) ≥25.0 kg/m²), completed 7-day diet records, venous blood draws, heterochromatic flicker photometry, assessment of intelligence quotient (IQ), and a cognitive flexibility task while undergoing electroencephalographic recording for event-related potential (ERP) extraction. Multiplicative interaction terms and hierarchical linear regressions, controlling for age, BMI, sex, annual household income, and IQ were utilized to assess independent and interactive contributions of dietary and biomarker data on Switch task outcomes. RESULTS: Higher intake of lutein+zeaxanthin and choline was associated interactively, but not independently, with faster reaction time (RT), after controlling for pertinent covariates. Dietary intake of lutein+zeaxanthin and choline was associated with serum lutein concentrations, but not with plasma choline metabolites nor macular pigmentation. Plasma phosphatidylcholine (PC) concentrations were associated with higher accuracy in Switch trials, while no other biomarkers were associated with cognitive outcomes. Dietary intake and biomarker data were not related to the N2 nor P3 ERP component. CONCLUSIONS: Among a sample of adults with overweight and obesity, greater intake of choline and lutein+zeaxanthin was associated with faster performance on a cognitive flexibility task. Future work examining methods of increasing consumption of both of these dietary components as a possible means of improving or maintaining cognitive flexibility among adults with overweight and obesity is therefore warranted.

Sedentary time is related to deficits in response inhibition among adults with overweight and obesity: An accelerometry and event-related brain potentials study.

Excessive sedentariness has been related to poorer cognitive control in adults. Sedentariness may compound obesity-related impairments in response inhibition, but its relationship to response inhibition remains poorly understood. This study investigated the relationship between accelerometer-measured sedentary time (ST, min/day), performance on the Oddball and NoGo tasks, N2 and P3-ERP indices of response inhibition and attentional control in 80 adults with overweight and obesity (55 females, Mage  = 35.2 ± 5.8 years, BMI = 32.8 ± 5.3 kg/m2 ). ST was not related to performance on the Oddball task. However, more sedentary adults had larger P3b amplitude to targets. Higher ST was also related to increased attentional resource allocation during NoGo target and nontarget trials as indicated by higher P3b amplitudes across centroparietal sites (C1, Cz, C2, CP1, CPz, CP2; ps ≤ .03). ST was negatively indirectly related to target accuracy on NoGo trials through its association with faster response times to nontargets (95% percentile bootstrap CI for a standardized effect: -0.182, -0.014). ST was not related to N2 amplitude on either Oddball or NoGo target trials. Adjustment for moderate-to-vigorous physical activity (MVPA; all models), age (models with P3b NoGo target amplitude, N2 NoGo target amplitude and latency), and % fat mass (models with target NoGo accuracy and N2 NoGo target amplitude) did not modulate behavioral findings. MVPA did not significantly predict P3b amplitude. Our results suggest suboptimal response inhibition due to trading accuracy for speed and despite the upregulation of attentional resources among more sedentary adults with overweight and obesity.

Systemic inflammation mediates the negative relationship between visceral adiposity and cognitive control.

Elevated visceral adipose tissue (VAT) has been associated with cardiometabolic risk factors including chronic systemic low-grade inflammation. Whereas the cognitive implications of inflammation have been extensively studied in preclinical models, the influence of inflammatory cytokines on cognitive function in humans is unclear. This study aimed to investigate the relations among VAT, inflammatory cytokines, and cognitive control. We hypothesized that inflammatory markers would mediate the negative influence of VAT on selective attention. Participants between 25 and 46 years (N = 115, 43 females) underwent a DXA scan to estimate VAT. A modified Eriksen Flanker task was used to assess attentional inhibitory control while event-related potentials were recorded. ELISA was used to quantify plasma C-reactive protein (CRP) and Interleukin-6 (IL-6) concentrations. Mediation modeling while controlling for diet quality and education level revealed that CRP concentrations significantly mediated the relationship between VAT and incongruent trial accuracy (indirect effect 95% CI {-0.24, -0.01}). Further, IL-6 concentrations had a significant mediation effect on the relationship between VAT and incongruent P3 peak latency (indirect effect 95% CI {0.05, 1.39}). These results suggest that mechanisms by which visceral adiposity exerts a negative influence on cognitive function includes systemic inflammation.

The relationships between prolonged sedentary time, physical activity, cognitive control, and P3 in adults with overweight and obesity.

BACKGROUND/OBJECTIVES: To assess the relationships between daily sedentary time (ST), prolonged ST, moderate-to-vigorous physical activity (MVPA), and behavioral and neuroelectric indices of cognitive control in adults with overweight and obesity (OW/OB). SUBJECTS/METHODS: A cross-sectional design was used. Overall, 89 adults (BMI = 31.9 ± 4.9 kg/m2) provided measures of ST, prolonged ST (i.e., ST accumulated in ≥20 min), and MVPA from a hip-worn accelerometer worn over 7 days. Inhibitory control was measured with a modified Eriksen flanker task and cognitive flexibility with task switching. The amplitude and the latency of the P3 component of event-related potentials during each task were used as measures of attentional resource allocation and information processing speed, respectively. RESULTS: After adjusting for ST and MVPA, prolonged ST was related to greater interference (i.e., a larger decrement in accuracy between congruent and incongruent trials of the flanker task) indicative of a specific relationship between prolonged ST and poorer inhibitory control. Before adjusting for ST, MVPA was related to a smaller Global Switch Cost expressed as larger (more positive) amplitude of the P3 difference wave (mixed-task minus single-task condition of the switch task). Adjustment for ST attenuated this association to non-significance. CONCLUSIONS: Our findings suggest that future interventions focused on improving inhibitory control in adults with OW/OB should target restructuring ST in addition to current efforts to increase MVPA.

Six-Minute Walking Test Performance Relates to Neurocognitive Abilities in Preschoolers.

This study investigated the relationship between six-minute walking test (6MWT) distance walked and preschool-aged children's academic abilities, and behavioral and event-related potentials (ERP) indices of cognitive control. There were 59 children (25 females; age: 5.0 ± 0.6 years) who completed a 6MWT (mean distance: 449.6 ± 82.0 m) to estimate cardiorespiratory fitness. The Woodcock Johnson Early Cognitive and Academic Development Test evaluated academic abilities. A modified Eriksen flanker, hearts and flowers task, and auditory oddball task eliciting ERPs (N2, P3) assessed cognitive control. After adjusting for adiposity, diet, and demographics, linear regressions resulted in positive relationships between 6MWT distance and General Intellectual Ability (ß = 0.25, Adj R2 = 0.04, p = 0.04) and Expressive Language (ß = 0.30, Adj R2 = 0.13, p = 0.02). 6MWT distance was positively correlated with congruent accuracy (ß = 0.29, Adj R2 = 0.18, p < 0.01) and negatively with incongruent reaction time (ß = -0.26, Adj R2 = 0.05, p = 0.04) during the flanker task, and positively with homogeneous (ß = 0.23, Adj R2 = 0.21, p = 0.04) and heterogeneous (ß = 0.26, Adj R2 = 0.40, p = 0.02) accuracy on the hearts and flowers task. Higher fit children showed faster N2 latencies and greater P3 amplitudes to target stimuli; however, these were at the trend level following the adjustment of covariates. These findings indicate that the positive influence of cardiorespiratory fitness on cognitive function is evident in 4-6-year-olds.

Dietary choline is related to neural efficiency during a selective attention task among middle-aged adults with overweight and obesity.

Objectives: Obesity is associated with poorer brain health and cognitive function. However, it is not clear whether specific dietary factors may provide neuroprotective effects among individuals with overweight and obesity. The aim of this study was to examine the impact of choline intake on neurophysiological markers of attentional control among young and middle-aged adults with overweight or obesity.Methods: 146 adults with BMI ≥25 kg/m2 (34.0 ± 5.9 years, 57 males) participated in the study. Behavioral performance (accuracy and reaction time) and neuroelectric indices (event-related brain potentials [ERPs]) of attentional inhibition were assessed during a Flanker task. Specifically, the amplitude and latency of the P3 waveform in a central-parietal region of interest (ROI) were used to index attentional resource allocation and information processing speed, respectively. Choline intake and overall diet quality (Healthy Eating Index [HEI-2015]) were assessed using 7-day diet records. Intelligence Quotient was assessed using the Kaufman-Brief Intelligence Test. Regression analyses were conducted to examine the relationship between habitual dietary choline intake and cognitive outcomes following adjustment of demographic factors, IQ, HEI-2015, and BMI.Results: Choline intake was selectively associated with a lower peak amplitude of the P300 waveform during incongruent trials (ß = -0.25, p = <0.01). No significant relationships were observed for accuracy or reaction time.Discussion: Higher choline intake is associated with more efficient neural processing among adults with overweight and obesity. Intervention are necessary to determine whether choline consumption provides neuroprotective effects for executive function among individuals with elevated weight status.

A systematic review of physical activity and cardiorespiratory fitness on P3b.

Given accumulating evidence indicating that acute and chronic physical activity and cardiorespiratory fitness are related to modulation of the P3b-ERP component, this systematic review provides an overview of the field across the last 30+ years and discusses future directions as the field continues to develop. A systematic review was conducted on studies of physical activity and cardiorespiratory fitness on P3b. PubMed, Web of Science, and Scopus were searched from database inception to March 28, 2018. Search results were limited to peer-reviewed and English-written studies investigating typically developed individuals. Seventy-two studies were selected, with 39 studies examining cross-sectional relationships between chronic physical activity (n = 19) and cardiorespiratory fitness (n = 20) with P3b, with 16 and 17 studies reporting associations of P3b with physical activity and cardiorespiratory fitness, respectively. Eight studies investigated the effects of chronic physical activity interventions, and all found effects on P3b. Eight studies investigating P3b during acute bouts of physical activity showed inconsistent results. Nineteen of 23 studies demonstrated acute modulation of P3b following exercise cessation. Conclusions drawn from this systematic review suggest that physical activity and cardiorespiratory fitness are associated with P3b modulation during cognitive control and attention tasks. Acute and chronic physical activity interventions modulate the P3b component, suggesting short- and long-term functional adaptations occurring in the brain to support cognitive processes. These summary findings suggest physical activity and cardiorespiratory fitness are beneficial to brain function and that P3b may serve as a biomarker of covert attentional processes to better understand the relationship of physical activity and cognition.

Effects of 12-week avocado consumption on cognitive function among adults with overweight and obesity.

OBJECTIVES: Excess adiposity increases risk for cognitive impairment. Consumption of avocado, a highly bioavailable source of the xanthophyll lutein, has been shown to improve retinal lutein accumulation and cognitive function. Thus, we evaluated the influence of avocado consumption on cognitive function and lutein status among adults with overweight and obesity using a randomized-controlled trial with matching design for pertinent study outcomes. METHODS: A cohort of 84 adults (25-45 years, 31 males) were randomized to a treatment group (N = 47) that received a 12-week daily meal with fresh Hass avocado or a control group (N = 37) that received an isocaloric meal (clinicaltrials.gov, NCT02740439). Serum lutein and macular pigment optical density (MPOD) were used to assess xanthophyll status. Attention and inhibition were assessed using the Flanker, Oddball and Nogo tasks with accompanying electroencephalographic (EEG) recording. RESULTS: Participants in the treatment group exhibited improvements in serum lutein and accuracy in the Flanker task. However, there were no relationships between performance and changes in lutein status, nor neuroelectric variables. No significant changes in MPOD were observed. CONCLUSION: Daily avocado intake over 12 weeks, after controlling for covariates, improved attentional inhibition and increased serum lutein concentrations among adults with overweight and obesity. However, the cognitive benefits were independent of changes in lutein concentrations. Additional work is necessary to determine non-carotenoid, or carotenoid interactive, mechanisms by which avocados may influence cognitive function.

Adiposity is related to neuroelectric indices of motor response preparation in preadolescent children.

OBJECTIVE: Event-related brain potentials (ERPs) have been utilized to study the cognitive implications of health-related behaviors, although many questions remain regarding the neural correlates underlying the cognition and adiposity relationship in childhood. Specifically, it is unknown whether excess fat mass is associated with the neural correlates of motor preparation and activation. The present work examined interrelationships between adiposity and ERPs that index inhibition, stimulus evaluation, and motor planning. METHOD: To further elucidate the neural components of inhibitory control that are sensitive to adiposity, N2, P3, and response- and stimulus-locked Lateralized Readiness Potential (LRPs) were measured while preadolescent children completed an attentional inhibition task. Whole body percent adiposity was measured via dual-energy x-ray absorptiometry (DXA). RESULTS: Adiposity was related to the response-locked LRP amplitudes and marginally to P3 amplitude during the incongruent trials, such that participants with less adiposity elicited larger LRP and P3 components. Furthermore, P3 was strongly related to participant reaction times, suggesting that while LRP is strongly associated with adiposity, P3 has a more direct relationship to behavioral task performance. CONCLUSIONS: The results suggest that while different cognitive functions may be affected by health-related characteristics, stimulus evaluation and motor activation may be particularly sensitive to excess adiposity in children. These findings extend previous work implicating adiposity in cognitive health in the pediatric population. STUDY IMPORTANCE: Clinical Registry Number: NCT02630667 at https://clinicaltrials.gov.

Macular Xanthophylls and Event-Related Brain Potentials among Overweight Adults and Those with Obesity.

SCOPE: Macular accumulation of xanthophyll carotenoids (lutein, zeaxanthin) is known to have neuroprotective potential, yet their influence on cognition among overweight adults and those with obesity remains limited. This study examines the impact of macular xanthophylls on attentional resource allocation and information processing speed among adults with BMI ≥ 25 kg m-2 . METHODS AND RESULTS: Adults between 25 and 45 years (N = 101) complete heterochromatic flicker photometry to determine macular pigment optical density (MPOD). Event-related brain potentials are recorded during a visual oddball task. Amplitude and latency of the N2 and P3 indexed attentional resource allocation and information processing speed. Covariates included age, sex, education, intelligence quotient (IQ), %Fat (DXA), and dietary lutein and zeaxanthin (Diet History Questionnaire II). MPOD is inversely related to P3 peak amplitude during standard trials and P3 peak latency during target trials. Therefore, individuals with higher MPOD dedicate fewer attentional resources when attentional demands are low while exhibiting faster information processing speed when attentional demands are increased. Further, MPOD is inversely related to the N2 mean amplitude during targets, signifying greater inhibitory control. CONCLUSION: These findings are the first to link macular xanthophylls to neuroelectric indices of attentional and inhibitory control among adults with overweight and obesity.

Visual sequential processing and language ability in children who are deaf or hard of hearing.

This study investigated the role of sequential processing in spoken language outcomes for children who are deaf or hard of hearing (DHH), ages 5;3-11;4, by comparing them to children with typical hearing (TH), ages 6;3-9;7, on sequential learning and memory tasks involving easily nameable and difficult-to-name visual stimuli. Children who are DHH performed more poorly on easily nameable sequencing tasks, which positively predicted receptive vocabulary scores. Results suggest sequential learning and memory may underlie delayed language skills of many children who are DHH. Implications for language development in children who are DHH are discussed.

Relations between mode of birth delivery and timing of developmental milestones and adiposity in preadolescence: A retrospective study.

BACKGROUND: Cesarean delivery (CS) is an increasingly common mode of delivery comprising over 30% of all deliveries in the U.S. The long-term impact of this delivery mode on child development remains unclear. AIMS: We investigated the relationship between mode of delivery (vaginal vs. CS) and timing of developmental milestones and adiposity in preadolescence, as well as additional milestones beyond motor/language development including toilet training, dressing, and feeding self. STUDY DESIGN: This study utilized a retrospective survey given to a parent/guardian and dual energy x-ray absorptiometry in preadolescence, respectively. A composite z-score was calculated based on nine questions pertaining to developmental milestones i.e., parent-reported age for supporting head by self, rolling over, sitting up, standing, walking, talking, toilet-training, dressing, and feeding self. SUBJECTS: 7-10-year-old (N = 104) children in East-Central Illinois. OUTCOME MEASURES: Composite z-score for timing of attainment of developmental milestones, mode of delivery, and preadolescent adiposity. RESULTS: Vaginally-born children had a lower composite z-score, signifying earlier attainment of developmental milestones, relative to both emergency and planned CS-born children. Further, elective CS-born children had greater adiposity in preadolescence, relative to vaginal and emergency cesarean-section born children. CONCLUSIONS: These findings suggest relationships between delivery mode, developmental milestones, and obesity in preadolescence. Additionally, they provide novel insights into the differential impact of elective versus emergency CS.

Visceral Adiposity and Diet Quality Are Differentially Associated With Cognitive Abilities and Early Academic Skills Among Preschool-Age Children.

Background: Visceral adipose tissue (VAT) and diet quality influence cognitive health in preadolescents; however, these relationships remain understudied among preschool-age children. Objectives: Investigate the relationship between VAT, diet quality, academic skills, and cognitive abilities among preschool-age children. Methods: Children between 4 and 5 years (N = 57) were enrolled in a cross-sectional study. Woodcock Johnson Early Cognitive and Academic Development Test (ECAD™) was utilized to assess General Intellectual Ability, Early Academic Skills, and Expressive Language. DXA was used to assess VAT. Diet quality was measured using the Healthy Eating Index-2015 (HEI-2015) based on 7-day food records. Results: Greater VAT was associated with poorer Early Academic Skills (r = -0.28, P = 0.03) whereas a diet pattern that included Fatty Acids, Whole Grains, Saturated Fats, Seafood and Plant Proteins, Total Vegetables, and Dairy was positively associated with General Intellectual Ability (r = 0.26, P = 0.04). Conclusions: Higher VAT is negatively related to Early Academic Skills whereas diet quality was positively and selectively related to intellectual abilities among preschool-age children. These findings indicate that the negative impact of abdominal adiposity on academic skills is evident as early as preschool-age while providing preliminary support for the potentially beneficial role of diet quality on cognitive abilities in early childhood.

Disordered Eating Attitudes and Behavioral and Neuroelectric Indices of Cognitive Flexibility in Individuals with Overweight and Obesity.

Impairment in cognitive flexibility is a trait characteristic among individuals with diagnosed eating disorders. However, the extent to which these relationships exist in individuals with overweight or obesity remains unclear. Furthermore, there is a lack of knowledge characterizing the neural underpinnings of these relationships. The current study aimed to investigate disordered eating attitudes and cognitive flexibility among adults with overweight and obesity. The Eating Attitudes Test (EAT-26) and a task-switching paradigm were collected from 132 adults (50 males, Body Mass Index (BMI) = 32.0 ± 5.8 kg/m²). Behavioral measures (accuracy and reaction time (RT)) and neuroelectric indices (amplitude and latency) of the P3 component were assessed. Hierarchical linear regressions, following adjustment of age, sex, intelligence quotient (IQ), weight status, and diet quality were developed using summative and subscale scores of the EAT-26. Higher EAT-26 summative scores, and the Dieting subscale, were related to longer RT. Only the Bulimia and Food Preoccupation subscale was related to longer P3 latency. The relationship between disordered eating attitudes and cognitive flexibility extends to individuals with overweight and obesity and is independent of age, sex, IQ, weight status, and diet quality. These findings are important, as differences in cognitive flexibility can lead to behavioral rigidity. Future work should aim to examine other neuroelectric components to identify where differences driving behavioral latencies may be occurring.

Oral Glucose Tolerance is Associated with Neuroelectric Indices of Attention Among Adults with Overweight and Obesity.

OBJECTIVE: This study aimed to elucidate the relationship between glucose levels and insulin resistance and sensitivity obtained from oral glucose tolerance tests and neurophysiological indices of attention among adults with overweight and obesity. METHODS: Forty adults with overweight or obesity (BMI ≥ 25 kg/m2 ) underwent dual-energy x-ray absorptiometry to assess visceral adipose tissue. Repeated venous blood samples were collected during an oral glucose tolerance test to measure insulin resistance (homeostatic model assessment of insulin resistance) and indices of insulin sensitivity (Matsuda index and Stumvoll metabolic clearance rate). Attention was assessed using event-related brain potentials recorded during a visual oddball task. Amplitude and latency of the P3 wave form in a central-parietal region of interest were used to index attentional resource allocation and information processing speed. RESULTS: Following adjustment for visceral adipose tissue, reduced values of Matsuda index and Stumvoll metabolic clearance rate (indicating poor insulin sensitivity) were correlated with longer peak latency, whereas insulin area under the curve was positively related to peak latency, indicating slower information processing. Individuals with decreased insulin sensitivity (Matsuda index < 4.3) had significantly longer P3 latencies compared with individuals with normal insulin sensitivity. CONCLUSIONS: Higher fasting glucose, but not homeostatic model assessment of insulin resistance, and reduced indices of glucose sensivity are associated with decrements in attention characterized by slower reaction time and slower information processing speed among adults with overweight and obesity.

Atypical predictive processing during visual statistical learning in children with developmental dyslexia: an event-related potential study.

Previous research suggests that individuals with developmental dyslexia perform below typical readers on non-linguistic cognitive tasks involving the learning and encoding of statistical-sequential patterns. However, the neural mechanisms underlying such a deficit have not been well examined. The aim of the present study was to investigate the event-related potential (ERP) correlates of sequence processing in a sample of children diagnosed with dyslexia using a non-linguistic visual statistical learning paradigm. Whereas the response time data suggested that both typical and atypical readers learned the statistical patterns embedded in the task, the ERP data suggested otherwise. Specifically, ERPs of the typically developing children (n = 12) showed a P300-like response indicative of learning, whereas the children diagnosed with a reading disorder (n = 8) showed no such ERP effects. These results may be due to intact implicit motor learning in the children with dyslexia but delayed attention-dependent predictive processing. These findings are consistent with other evidence suggesting that differences in statistical learning ability might underlie some of the reading deficits observed in developmental dyslexia.

Macular Xanthophylls Are Related to Intellectual Ability among Adults with Overweight and Obesity.

Excess adiposity or obesity has been inversely related to cognitive function and macular xanthophyll status. However, whether the neuroprotective effects of macular xanthophylls on cognitive function are independent of excess adiposity is unclear. We investigated the relationship between macular xanthophylls and intellectual ability among adults (N = 114) between 25 and 45 years with overweight and obesity (≥25 kg/m²). Dual energy X-ray absorptiometry and heterochromatic flicker photometry were used to assess whole body adiposity (%Fat) and macular pigment optical density (MPOD), respectively. Dietary xanthophylls (lutein and zeaxanthin) were assessed using 7-day diet records. The Kaufman Brief Intelligence Test-2 (KBIT-2) was used to assess general intelligence (IQ) as well as fluid and crystallized intelligence. Bivariate correlations revealed that MPOD was inversely related to %Fat and positively associated with IQ and fluid intelligence. Although %Fat was inversely correlated to IQ and fluid intelligence, this relationship did not persist following adjustment for sex and MPOD. Further, MPOD was an independent predictor of IQ and fluid intelligence. However, no significant relationships were observed between MPOD and crystalized intelligence. These results suggest that macular xanthophylls are selectively related to fluid intelligence, regardless of degree of adiposity among adults with overweight and obesity.