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Sensitivity to human faces has been suggested to be an early emerging capacity that promotes social interaction. However, the developmental processes that lead to cortical specialization to faces has remained unclear. The current study investigated both cortical sensitivity and categorical specificity through event-related potentials (ERPs) previously implicated in face processing in 7-month-old infants (N290) and adults (N170). Using a category-specific repetition/adaptation paradigm, cortical specificity to human faces, or control stimuli (cat faces), was operationalized as changes in ERP amplitude between conditions where a face probe was alternated with categorically similar or dissimilar adaptors. In adults, increased N170 for human vs. cat faces and category-specific release from adaptation for face probes alternated with cat adaptors was found. In infants, a larger N290 was found for cat vs. human probes. Category-specific repetition effects were also found in infant N290 and the P1-N290 peak-to-peak response where latter indicated category-specific release from adaptation for human face probes resembling that found in adults. The results suggest cortical specificity to human faces during the first year of life. Encoding of unfamiliar cat stimuli might explain N290 amplification found in infants. [ABSTRACT FROM AUTHOR]

This study examined approach-motivation related brain activity (frontal electroencephalogram [EEG] asymmetry) in response to direct and averted gaze in 3- to 6-year-old typically developing (TD) children, children with autism spectrum disorder (ASD), and those with intellectual disability (ID). We found that, in TD children, direct gaze elicited greater approach-related frontal EEG activity than did downcast gaze. This pattern of activity was in contrast to that observed in children with ASD, who showed greater approach-related activity in response to downcast gaze than to direct gaze. ID children did not differ in their responses to different gaze conditions. These findings indicate that another person's direct gaze does not elicit approach-motivation related brain activity in young children with ASD. [ABSTRACT FROM AUTHOR]

Background: Prenatal exposure to maternal depression, with or without maternal medical antidepressant treatment, may pose a risk to the child's cognitive and behavioral development. Targeting one of the core functions of behavioral regulation, we investigated both behavioral and neural indices of interference suppression in both exposed and control participants at preschool age. Methods: Children ( N = 80, M = 68.60 months, SD = 5.57) with prenatal exposure to maternal depression with (SSRI, N = 21) and without (DEP, N = 33) antidepressant treatment were tested together with unexposed children (CON, N = 26) on a behavioral flanker task while recording event-related potentials (ERPs). ERPs were extracted from trials with congruent/incongruent flankers and speeded/slow response times (RT). Findings: Effects of flanker congruence were found in both behavioral indices and the late slow wave ERP (LSW, 500-800 ms), across all groups in the expected directions. Further, increased amplitude of the N2 (350-450 ms) and the LSW potential was found in trials with speeded vs slow RT. Interestingly, the parietal N2 in speeded trials showed decreased latency among children in the CON group but not among the other children. No other effects of group on ERP or behavioral measures were found. Conclusion: While interference effects were evident in behavioral and ERP measures, prenatal exposure to SSRIs and DEP was not directly associated with abilities of interference suppression. However, RT in the flanker task was associated with N2 and LSW potentials. Importantly, the interaction between RT and participant group upon parietal N2 latency may suggest effects of prenatal exposure on neural efficiency. [ABSTRACT FROM AUTHOR]

Saccadic reaction time (SRT) is a widely used dependent variable in eye-tracking studies of human cognition and its disorders. SRTs are also frequently measured in studies with special populations, such as infants and young children, who are limited in their ability to follow verbal instructions and remain in a stable position over time. In this article, we describe a library of MATLAB routines (Mathworks, Natick, MA) that are designed to (1) enable completely automated implementation of SRT analysis for multiple data sets and (2) cope with the unique challenges of analyzing SRTs from eye-tracking data collected from poorly cooperating participants. The library includes preprocessing and SRT analysis routines. The preprocessing routines (i.e., moving median filter and interpolation) are designed to remove technical artifacts and missing samples from raw eye-tracking data. The SRTs are detected by a simple algorithm that identifies the last point of gaze in the area of interest, but, critically, the extracted SRTs are further subjected to a number of postanalysis verification checks to exclude values contaminated by artifacts. Example analyses of data from 5- to 11-month-old infants demonstrated that SRTs extracted with the proposed routines were in high agreement with SRTs obtained manually from video records, robust against potential sources of artifact, and exhibited moderate to high test-retest stability. We propose that the present library has wide utility in standardizing and automating SRT-based cognitive testing in various populations. The MATLAB routines are open source and can be downloaded from . [ABSTRACT FROM AUTHOR]

Recording of event-related potentials (ERPs) is one of the best-suited technologies for examining brain function in human infants. Yet the existing software packages are not optimized for the unique requirements of analyzing artifact-prone ERP data from infants. We developed a new graphical user interface that enables an efficient implementation of a two-stage approach to the analysis of infant ERPs. In the first stage, video records of infant behavior are synchronized with ERPs at the level of individual trials to reject epochs with noncompliant behavior and other artifacts. In the second stage, the interface calls MATLAB and EEGLAB (Delorme & Makeig, Journal of Neuroscience Methods 134(1):9-21, ) functions for further preprocessing of the ERP signal itself (i.e., filtering, artifact removal, interpolation, and rereferencing). Finally, methods are included for data visualization and analysis by using bootstrapped group averages. Analyses of simulated and real EEG data demonstrated that the proposed approach can be effectively used to establish task compliance, remove various types of artifacts, and perform representative visualizations and statistical comparisons of ERPs. The interface is available for download from in a format that is widely applicable to ERP studies with special populations and open for further editing by users. [ABSTRACT FROM AUTHOR]