A Within-subjects Experimental Protocol to Assess the Effects of Social Input on Infant EEG
Ashley M St John1, Katie Kao2, Meia Chita-Tegmark2
1Department of Psychological and Brain Sciences, Boston University; astjohn@bu.edu.
Insights
This study introduces a new electroencephalography (EEG) method to measure infant brain activity during social interactions. The findings show distinct neural patterns related to different social and nonsocial contexts in infants.
Area of Science:
- Developmental neuroscience
- Cognitive neuroscience
- Infant research
Background:
- Social interaction is crucial for infant brain development.
- Limited research exists on neural activation during infant social interactions.
- Electroencephalography (EEG) power is suitable for assessing infant neural activity.
Purpose of the Study:
- To present a novel EEG paradigm for assessing infant neural activity in social and nonsocial contexts.
- To differentiate the effects of various social inputs (language, face-to-face interaction, joint attention) on infant EEG.
- To provide a foundation for studying individual differences in social brain development.
Main Methods:
- A within-subjects experimental design with four controlled conditions.
- Conditions included nonsocial (object viewing), joint attention (experimenter-guided attention), language-only, and face-to-face interaction.
- Infant EEG power was recorded and analyzed across conditions.
Main Results:
- Infant EEG power significantly varied across the different social and nonsocial conditions.
- Neural activation patterns differed across brain regions depending on the context.
- Results support the functional relevance of EEG power in response to environmental stimuli.
Conclusions:
- The developed EEG paradigm effectively distinguishes neural responses to social versus nonsocial contexts in infants.
- This method allows for detailed examination of how specific social inputs influence infant neural activation.
- Future research can utilize this paradigm to explore factors influencing social brain development.
Abstract:
Despite the importance of social interactions for infant brain development, little research has assessed functional neural activation while infants socially interact. Electroencephalography (EEG) power is an advantageous technique to assess infant functional neural activation. However, many studies record infant EEG only during one baseline condition. This protocol describes a paradigm that is designed to comprehensively assess infant EEG activity in both social and nonsocial contexts as well as tease apart how different types of social inputs differentially relate to infant EEG. The within-subjects paradigm includes four controlled conditions. In the nonsocial condition, infants view objects on computer screens. The joint attention condition involves an experimenter directing the infant's attention to pictures. The joint attention condition includes three types of social input: language, face-to-face interaction, and the presence of joint attention. Differences in infant EEG between the nonsocial and joint attention conditions could be due to any of these three types of input. Therefore, two additional conditions (one with language input while the experimenter is hidden behind a screen and one with face-to-face interaction) were included to assess the driving contextual factors in patterns of infant neural activation. Representative results demonstrate that infant EEG power varied by condition, both overall and differentially by brain region, supporting the functional nature of infant EEG power. This technique is advantageous in that it includes conditions that are clearly social or nonsocial and allows for examination of how specific types of social input relate to EEG power. This paradigm can be used to assess how individual differences in age, affect, socioeconomic status, and parent-infant interaction quality relate to the development of the social brain. Based on the demonstrated functional nature of infant EEG power, future studies should consider the role of EEG recording context and design conditions that are clearly social or nonsocial.
