Frontal EEG power during a novel task: Links with temperament

• In Event: Poster Session 11
  In Poster Session: PS 11 Topic - Biological Processes: Neuroscience and Genetics

Abstract

Frontal electroencephalography (EEG) asymmetry reflects individual dispositional differences, with greater right hemisphere activation linked to withdrawal motivation/emotions and greater left asymmetry associated with approach. Related studies have largely focused on baseline asymmetry values, thought to represent trait aspects of these motivations/emotions. However, frontal EEG asymmetry responses in the context of experimental manipulations were emphasized in the Capability Model (Coan, John, Allen, & McKnight, 2006), and described as meaningful individual differences reflecting interactions between the emotional demands of specific situations and the emotion-regulatory abilities individuals bring to these situations. The Masks episode included in the Laboratory Temperament Assessment Battery (Lab-TAB; Goldsmith & Rothbart, 1996) was designed to elicit reactions to novelty, and EEG asymmetry during this task has been analyzed in previous research (Buss et al., 2003; Diaz & Bell, 2012), with relative right frontal asymmetry linked to fearful behaviors. Additionally, it is critical to consider activation within each hemisphere to discern hyper vs. hypoactivation underlying frontal asymmetry, and unique contributions to lateralized brain activity (Fox, 1994). Right (F4) activation and left (F3) hypoactivation independently accounted for variance in sadness and salivary cortisol at 6-months of age (Buss et al., 2003), and were associated with unique developmental effects (Gartstein et. al., 2020).

The present study considered infant temperament attributes ascertained via the Infant Behavior Questionnaire-Revised (IBQ-R; Gartstein & Rothbart, 2003) and frontal EEG hemispheric activity during the Masks episode. It was hypothesized that infants with higher Negative Affectivity (NA) would display greater right frontal activation, and those higher in Surgency/Positive Affect (SPA) would exhibit stronger activation on the left during the Masks episode, after controlling for baseline power values.

Mothers with infants 6-12 months of age were recruited with only families of healthy infants (e.g., no medical complications) eligible to participate. Families meeting criteria (N=62) completed the IBQ-R, with NA and SPA considered as predictors of frontal alpha power. Mothers completed the IBQ-R within 2 weeks of the laboratory visit. EEG was recorded during baseline (with infants achieving a quiet/alert states while watching Baby Mozart video for 1 minute) and Masks, analyzed per standard procedures (Bell & Cuevas, 2012). The natural log (ln) of left frontal (F3) power and the ln of right frontal (F4) power in the 6-9 Hz “baby alpha band” served as dependent variables.

Hierarchical regression models were considered, initially including covariates (i.e., infant age and sex), which were trimmed if not deemed significant. NA and SPA did not account for right frontal (F4) activity, controlling for baseline, predicting F3 power only (Table 1) in the negative direction. Both temperament factors were associated with stronger left-hemisphere activation during masks, as alpha power is considered to have an inhibitory effect on brain activity (Allen, Coan, & Nazarian, 2004). Initial factor-level analyses were followed by simple correlations, computed to discern contributions of fine-grained attributes. Only Smiling/Laughter was significantly negatively correlated with F3 power (Table 1). Overall results indicate left frontal activation in response to novelty is associated with greater capacity to express joy, and to general reactivity more broadly.

Authors

• Allegra Campagna, Washington State University
  Presenting Author

• Jonathan Bayley, Washington State University
  Non-Presenting Author

• Victoria Jones, Washington State University
  Non-Presenting Author

• Christie Pham, Washington State University
  Non-Presenting Author

• Josh Underwood, Washington State University
  Non-Presenting Author

• Maria Amy Gartstein, Washington State University
  Non-Presenting Author