EEG functional connectivity in infants at elevated familial likelihood for autism spectrum disorder.

Background: Many studies have reported that autism spectrum disorder (ASD) is associated with atypical structural and functional connectivity. However, we know relatively little about the development of these differences in infancy.

Methods: We used a high-density electroencephalogram (EEG) dataset pooled from two independent infant sibling cohorts, to characterize such neurodevelopmental deviations during the first years of life.

EEG functional connectivity in infants at elevated familial risk for autism spectrum disorder.

Background: Many studies have reported that autism spectrum disorder (ASD) is associated with atypical structural and functional connectivity. However, relatively little is known about the development of these differences in infancy and on how trajectories may vary between sexes.

Methods: We used the International Infant EEG Platform (EEG-IP), a high-density electroencephalogram (EEG) dataset pooled from two independent infant sibling cohorts, to characterize such neurodevelopmental deviations during the first years of life.

Inter-trial theta phase consistency during face processing in infants is associated with later emerging autism.

A growing body of research suggests that consistency in cortical activity may be a promising neurophysiological marker of autism spectrum disorder (ASD). In the current study we examined inter-trial coherence, a measure of phase consistency across trials, in the theta range (t-ITC: 3-6 Hz), as theta has been implicated in the processing of social and emotional stimuli in infants and adults. The sample included infants who had an older sibling with a confirmed ASD diagnosis and typically developing (TD) infants with no family history of ASD.

Increased alpha suppression with age during involuntary memory retrieval.

Recent work suggests that while voluntary episodic memory declines with age, involuntary episodic memory, which comes to mind spontaneously without intention, remains relatively intact. However, the neurophysiology underlying these differences has yet to be established. The current study used electroencephalography (EEG) to investigate voluntary and involuntary retrieval in older and younger adults.

An ERP investigation of children and adolescents' sensitivity to wins and losses during a peer observation manipulation.

The purpose of this ERP P3 study was to test a peer observation manipulation (being observed by a peer versus being alone) on neural markers of attention to reward (win-feedback) and punishment (loss-feedback) during the Balloon Analogue Risk Task. Participants (126 children, 53 % male, 8-10 years; 196 early adolescents, 50 % male, 11-13 years; and 121 mid-adolescents, 52 % male, 14-16 years) were assessed by age group and pubertal status. Individual differences in how participants felt about being observed by a peer, and self-report personality factors, also were examined.

Association between spectral electroencephalography power and autism risk and diagnosis in early development.

Autism spectrum disorder (ASD) has its origins in the atypical development of brain networks. Infants who are at high familial risk for, and later diagnosed with ASD, show atypical activity in multiple electroencephalography (EEG) oscillatory measures. However, infant-sibling studies are often constrained by small sample sizes.

Use of Empirical Mode Decomposition in ERP Analysis to Classify Familial Risk and Diagnostic Outcomes for Autism Spectrum Disorder.

Event-related potentials (ERPs) activated by faces and gaze processing are found in individuals with autism spectrum disorder (ASD) in the early stages of their development and may serve as a putative biomarker to supplement behavioral diagnosis. We present a novel approach to the classification of visual ERPs collected from 6-month-old infants using intrinsic mode functions (IMFs) derived from empirical mode decomposition (EMD). Selected features were used as inputs to two machine learning methods (support vector machines and -nearest neighbors (-NN)) using nested cross validation.

12-Month peak alpha frequency is a correlate but not a longitudinal predictor of non-verbal cognitive abilities in infants at low and high risk for autism spectrum disorder.

Although studies of PAF in individuals with autism spectrum disorder (ASD) report group differences and associations with non-verbal cognitive ability, it is not known how PAF relates to familial risk for ASD, and whether similar associations with cognition in are present in infancy. Using a large multi-site prospective longitudinal dataset of infants with low and high familial risk for ASD, metrics of PAF at 12 months were extracted and growth curves estimated for cognitive development between 12-36 months. Analyses tested whether PAF 1) differs between low and high risk infants, 2) is associated with concurrent non-verbal/verbal cognitive ability and 3) predicts developmental change in non-verbal/verbal ability.

EEG Integrated Platform Lossless (EEG-IP-L) pre-processing pipeline for objective signal quality assessment incorporating data annotation and blind source separation.

Background: The methods available for pre-processing EEG data are rapidly evolving as researchers gain access to vast computational resources; however, the field currently lacks a set of standardized approaches for data characterization, efficient interactive quality control review procedures, and large-scale automated processing that is compatible with High Performance Computing (HPC) resources.

New Method: In this paper we describe an infrastructure for the development of standardized procedures for semi and fully automated pre-processing of EEG data. Our pipeline incorporates several methods to isolate cortical signal from noise, maintain maximal information from raw recordings and provide comprehensive quality control and data visualization.

EEG-IP: an international infant EEG data integration platform for the study of risk and resilience in autism and related conditions.

Background: Establishing reliable predictive and diganostic biomarkers of autism would enhance early identification and facilitate targeted intervention during periods of greatest plasticity in early brain development. High impact research on biomarkers is currently limited by relatively small sample sizes and the complexity of the autism phenotype.

Methods: EEG-IP is an International Infant EEG Data Integration Platform developed to advance biomarker discovery by enhancing the large scale integration of multi-site data.

Cognitive control in the eye of the beholder: Electrocortical theta and alpha modulation during response preparation in a cued saccade task.

The oscillatory dynamics of medial frontal EEG theta and posterior alpha are implicated in the modulation of attention and cognitive control. We used a novel saccade cueing paradigm to examine whether theta and alpha are modulated by task difficulty during response preparation. After isolating and functionally classifying medial frontal and posterior alpha independent components, the EEG spectral power in these components was calculated on pro- and anti-saccade trials prior to response probes.

Watch out! Medial frontal cortex is activated by cues signaling potential changes in response demands.

The human medial frontal cortex and especially the anterior cingulate cortex (ACC) have been implicated in several aspects of performance monitoring. We examined event-related EEG during a general process of controlling attention by using a novel paradigm to elicit a medial frontal negativity (MFN) to stimuli that indicate potential changes in future response demands. Independent components analysis revealed that the latent factors that accounted for MFN activity to such changes also accounted for activity associated with the error-related negativity and the NoGo inhibitory N2.

A wavelet based algorithm for the identification of oscillatory event-related potential components.

Event related potentials (ERPs) are very feeble alterations in the ongoing electroencephalogram (EEG) and their detection is a challenging problem. Based on the unique time-based parameters derived from wavelet coefficients and the asymmetry property of wavelets a novel algorithm to separate ERP components in single-trial EEG data is described. Though illustrated as a specific application to N170 ERP detection, the algorithm is a generalized approach that can be easily adapted to isolate different kinds of ERP components.

Deconstructing the early visual electrocortical responses to face and house stimuli.

The initial timing of face-specific effects in event-related potentials (ERPs) is a point of contention in face-processing research. The occasional reports of a larger P100 to face stimuli compared to other image categories is often attributed to differences in low-level stimulus characteristics. Separating the P100 from the classic N170 effect has not been done except by adjusting stimuli to control for low-level stimulus characteristics, which yields robust face effects only after 130 ms.

The error-related negativity associated with different strength of stimulus-response interference.

Objective: The present study was aimed at clarifying the effect of stimulus-response compatibility (SRC) interference on the ERN.

Methods: We compared ERNs in two tasks differing in the level of interference, an arrow (AR) task classified as a Simon task and a more complex arrow-orientation (AO) task classified as a spatial-Stroop task. We also compared ERNs between partial errors (with initial incorrect movement corrected by a proper full response) and overt (uncorrected) errors.

EEG coherence in early-blind humans during sound localization.

Human blind individuals have demonstrated cross-modal plasticity in research over the past decade. In one such study, we showed that early-blind subjects were able to localize sound sources accurately despite the lack of visual input for the calibration of their auditory space. A further ERP study with these subjects also revealed N1 and P3 components during a sound localization task to be more posteriorly distributed than for sighted controls, indicating an involvement of posterior regions in sound localization for blind subjects not present for sighted subjects.