Frontal Brain Asymmetry and the Trajectory of Shyness Across the Early School Years

Links between social avoidance and frontal alpha asymmetry during processing emotional facial stimuli: An exploratory study

Individuals who are socially avoidant actively remove themselves from opportunities for social interaction and have a strong desire for solitude. Although social avoidance is associated with a host of adjustment difficulties, its neural substrates remain under-explored. To address this gap, we conducted an exploratory study to compare electroencephalography (EEG) frontal alpha asymmetry (FAA) scores during processing emotional facial stimuli in socially avoidant and non-withdrawn comparison individuals. From an original sample of N = 384 undergraduate students, 25 avoidant and 27 comparison individuals were identified. For this subset of participants, EEG modulations and self-reported experience ratings during a picture processing task were assessed. Among the results, the socially avoidant group's ratings of positive stimuli were significantly lower than the non-withdrawn comparison group. The socially avoidant group also had significantly lower FAA scores in response to positive stimuli than the comparison group. Further, asymmetry scores of the comparison group in the positive conditions were higher than in the negative and neutral conditions. However, there were no significant differences between these three conditions in the socially avoidant group. Our results suggest that socially avoidant individuals may eschew interpersonal relationships because of a relatively greater right hemisphere cortical activity, which may contribute to a withdrawal motivation when confronted with negative emotional stimuli in social contexts.

Longitudinal investigation of shyness and physiological vulnerability: Moderating influences of attention biases to threat and safety

Shyness has long been identified as a vulnerability factor to developing psychosocial problems, but there is heterogeneity in these observed outcomes. One potential factor underlying these relations is individual differences in threat sensitivity. Using a longitudinal design, we examined whether attentional biases toward social threat and safety measured during adulthood moderated the association between shyness measured in emerging adulthood (N = 83, n_female = 48; M_age = 23.56 years, SD_age = 1.09 years) and frontal electroencephalogram (EEG) asymmetry at rest, a physiological index of vulnerability to psychopathology, measured nearly a decade later in adulthood (M_age = 31.68 years, SD_age = 2.27 years). We found that only biases to threat moderated the association between shyness and resting frontal EEG asymmetry longitudinally. In individuals who displayed relative vigilance to social threat, shyness was associated with greater relative right frontal EEG activity at rest (i.e., increased physiological vulnerability). These findings suggest that attentional biases to threat may play a role in understanding the relation between shyness and some known physiological vulnerabilities to psychopathology in adults.

Temperamental Shyness and Anger/Frustration in Childhood: Normative Development, Individual Differences, and the Impacts of Maternal Intrusiveness and Frontal Electroencephalogram Asymmetry

This study used latent growth curve modeling to identify normative development and individual differences in the developmental patterns of shyness and anger/frustration across childhood. This study also examined the impacts of maternal intrusiveness and frontal electroencephalogram (EEG) asymmetry at age 4 on the developmental patterns of shyness and anger/frustration. 180 children (92 boys, 88 girls; M_age  = 4.07 years at baseline; 75.6% White, 18.3% Black, 6.1% multiracial/other) participated in the study. Normative development included significant linear decreases in shyness and anger/frustration. Individual variation existed in the developmental patterns. Children with left frontal EEG asymmetry showed a faster decreasing pattern of shyness. Children who experienced higher maternal intrusiveness and had left frontal EEG asymmetry showed a slower decreasing pattern of anger/frustration.

Trajectories of behavioral avoidance in real time: Associations with temperament and physiological dysregulation in preschoolers

Although excessive avoidance has been implicated in mental health problems and socioemotional difficulties, relatively little is known about dynamic changes of avoidance behaviors. We used a latent class growth analysis to examine the temporal course of avoidance behaviors in real time and determined whether the derived classes were distinguishable on temperament and physiological markers of regulation and reactivity (N = 153; M_age = 4.20 years). A three-class solution was found and identified a low, medium, and high increasing avoidance group. The high and increasing avoidance group had the highest physiological reactivity (cortisol reactivity) and shyness, and the lowest physiological regulation (i.e., respiratory sinus arrythmia suppression). High and increasing avoidance may therefore be associated with temperamental and physiological indices of risk implicated in maladjustment and highlight the value of data-driven, group-based approaches for examining dynamic patterns of behavior.

A longitudinal study investigating trajectories of sensitivity to threat over time and their association with alpha asymmetry among children and adolescents

Research has yet to investigate trajectories of sensitivity to threat across childhood and adolescence. Further, neural associations of these trajectories remain unknown. The current 3-year study used a latent class growth curve analysis to investigate whether there were distinct trajectories of sensitivity to threat among children and adolescents over time (N = 363; age range at Time 1 = 8-14). We also examined whether alpha asymmetry (a neural index of motivational tendencies) was associated with the different trajectories. Results revealed three distinct trajectory groups (1) high-stable sensitivity to threat, (2) moderate-increasing sensitivity to threat and (3) low-stable sensitivity to threat. The high-stable sensitivity to threat group had greater right frontal asymmetry activation (i.e., greater neural avoidance motivation) than the other two groups. Additionally, females, those with higher parental education, and individuals with more advanced pubertal development (but not age) had greater odds of being part of the high-stable sensitivity to threat group compared to the other groups. Of interest, puberty rather than age may be an important indicator of heightened sensitivity to threat.

Social Withdrawal and Anxiety in Childhood and Adolescence: Interaction between Individual Tendencies and Interpersonal Learning Mechanisms in Development : Introduction to the Special Issue

In this introduction to the special issue on Social Withdrawal and Anxiety in Childhood and Adolescence: Interaction Between Individual Tendencies and Interpersonal Learning Mechanisms in Development, we analyze conceptual models guiding the twelve studies featured herein. Findings from multiple investigations support Diathesis - Stress Models which emphasize the role of parent- or peer-related interpersonal stress in strengthening affective-behavioral or biological vulnerabilities (diatheses) to anxious solitude or social anxiety. Other investigations support only child vulnerability effects, consistent with a Diathesis-only Model, but such effects are often framed as potentially part of broader Diathesis-Stress or Child by Environment Transactional Models. Next we discuss novelty in development as defined as directional change in the progression of affective-behavioral patterns over time. Novelty in development is postulated in: 1) a Chronic Stress Model that proposes that interpersonal stress can generate or maintain social withdrawal and anxiety; 2) Stress Generation and Transactional Models that propose that child vulnerability can evoke interpersonal stress; and 3) an Ecological Transition Model that proposes that ecological transitions can serve as turning points prompting reorganization in the child-environment system which can result in the deflection of previous patterns of adjustment onto alternate trajectories. We also highlight additional themes from the set of studies found herein. These themes include the significance of gender and culture vis-à-vis the development of social withdrawal and anxiety. Other themes include motivations for social withdrawal; the influence of peer predictability on social withdrawal and brain function; and how the study of multiple developmental pathways has been supported by contemporary analytic techniques.

Trajectories of Observed Shyness and Psychosocial Adjustment in Children

Shyness can manifest as inhibition, fear, and avoidance in the context of social novelty and situations of perceived social evaluation. In the present study, 130 children (M_age = 7.6 years, SD = 1.8) participated in a videotaped self-presentation task across three separate visits spanning approximately 3 years in early and middle childhood. Children's observed shyness was best characterized by two trajectories, including a high-stable class (19%) and a low-stable class (81%). Girls were more likely than boys to follow a pattern of high-stable observed shyness. Further, children in the high-stable observed shyness class were rated by parents and teachers as more socially anxious relative to children in the low-stable class, and boys in the high-stable observed shyness class were rated by their teachers as displaying more depressive symptoms relative to girls. These findings suggest that a subset of children display stable behavioral shyness, and this is correlated with psychosocial functioning.

Positive Shyness in the Brain: Frontal Electroencephalogram Alpha Asymmetry and Delta-Beta Correlation in Children

Positive shyness is thought to be an approach-dominant form of shyness, whereas non-positive shyness is thought to be an avoidance-dominant form of shyness. This study examined electrocortical and behavioral correlates of motivation and emotion in relation to these shy subtypes in 67 children (M_age  = 10.41 years, SD = 3.23). Using resting state electroencephalography, findings revealed that positive shy and low shy children had greater relative left frontal alpha asymmetry compared to non-positive shy children, and positive shy children had a higher frontal delta-beta correlation compared to other groups. Non-positive shy children scored highest on parent-reported school avoidance. These findings converge with previous work reporting distinct correlates in positive and non-positive shyness, extending this to two brain measures of motivation and emotion.

Psychophysiological influences on personality trajectories in adolescent females exposed to child maltreatment

Although child maltreatment is a major public health concern, which adversely affects psychological and physical development, we know relatively little concerning psychophysiological and personality factors that may modify risk in children exposed to maltreatment. Using a three-wave, short-term prospective design, we examined the influence of individual differences in two disparate psychophysiological measures of risk (i.e., resting frontal brain electrical activity and respiratory sinus arrhythmia) on the trajectories of extraversion and neuroticism in a sample of female adolescents (N = 55; M age = 14.02 years) exposed to child maltreatment. Adolescents exposed to child maltreatment with relatively higher left frontal absolute alpha power (i.e., lower brain activity) at rest exhibited increasing trajectories of extraversion, and adolescents exposed to child maltreatment with relatively lower respiratory sinus arrhythmia at rest displayed increasing trajectories of neuroticism over 1 year. Individual differences in psychophysiological measures indexing resting central and peripheral nervous system activity may therefore differentially influence personality characteristics in adolescent females exposed to child maltreatment.