Dynamic Responses in Brain Networks to Social Feedback: A Dual EEG Acquisition Study in Adolescent Couples

Abstract

Adolescence is a sensitive period for the development of romantic relationships. During this period the maturation of frontolimbic networks is particularly important for the capacity to regulate emotional experiences. In previous research, both functional magnetic resonance imaging (fMRI) and dense array electroencephalography (dEEG) measures have suggested that responses in limbic regions are enhanced in adolescents experiencing social rejection. In the present research, we examined social acceptance and rejection from romantic partners as they engaged in a Chatroom Interact Task. Dual 128-channel dEEG systems were used to record neural responses to acceptance and rejection from both adolescent romantic partners and unfamiliar peers (N = 75). We employed a two-step temporal principal component analysis (PCA) and spatial independent component analysis (ICA) approach to statistically identify the neural components related to social feedback. Results revealed that the early (288 ms) discrimination between acceptance and rejection reflected by the P3a component was significant for the romantic partner but not the unfamiliar peer. In contrast, the later (364 ms) P3b component discriminated between acceptance and rejection for both partners and peers. The two-step approach (PCA then ICA) was better able than either PCA or ICA alone in separating these components of the brain's electrical activity that reflected both temporal and spatial phases of the brain's processing of social feedback.

Keywords: adolescent couples; dense-array EEG; event-related potential; principal component analysis; social interaction; source localization.

Figure 1

Representation of the Chatroom Interact Task. During the participant SELECTION block, both participants viewed 6 player profiles as an introduction to the task (2 participant profiles; “Emily” and “Zach,” two additional fictive males and females). Then, participants were instructed to choose the person who they would like to talk to regarding the topic displayed under the players' photos. In this particular example, we showed the player timeline of Emily (picture shown in the left corner) who was making selections between 2 players with a “left” or “right” button press. The selected or “accepted” player was subsequently highlighted with a green square on their picture. The unselected or “rejected” player was labeled with a red “X” over their picture. Following the participant selection block, fictitious feedback was provided by peers and the romantic partner in the FEEDBACK blocks, indicating whether the participant was accepted or rejected. Feedback was randomized by the experimenters and believed by the subjects. In the peer FEEDBACK blocks, participants would see their peers making selections. In this particular example, Emily (participant) viewed that Alexis (peer, displayed in the left corner) chose the participant to talk about movies, which was a peer acceptance trial. Then Alexis (peer) chose Jessica (peer) over Emily (participant) to talk about relationships, which was a peer rejection trial. This was followed by a filler trial where the participant, Emily, was not displayed as an option. In the romantic partner FEEDBACK block, participants viewed their romantic partners' selections. In this case, Emily (participant) watched Zach (romantic partner) selecting Emily to talk about movies, which was a romantic partner acceptance trial. However, Zach chose Jessica (peer) over Emily (participant) to talk about relationships, which was a romantic partner rejection trial. Note that only the peer and romantic partner FEEDBACK blocks were analyzed in the current study.

Figure 2

Original grand-average ERP waveforms at Fz and Pz. Signals were averaged across all subjects for four conditions (1,000 ms epoch). Stimulus onset was plotted as vertical dashed line. The thickness of the traces reflects the standard error through from subject-by-subject variations.

Figure 3

C1 component properties. (A) Component mean waveforms were at parietal sites at electrode E79 for all conditions. (B) Topography map of C1 was showing voltage distribution at 364 ms for partner acceptance condition. The white circle highlighted the location of channel E79 and block dots indicated all the 129 channels. Orientation was top looking down with nose at the top. (C) Scalp voltage distribution was on the atlas head model. (D) Source intensity on the vertical axis was shown in standardized units for component C1. (E) Source data was displayed and projected onto MRI slices. The area within the green border represented the posterior cingulate cortex.

Figure 4

C2 component properties. (A) Component mean waveforms were at midfrontal sites at electrode FCz (E6) for all conditions. (B) Topography map of C2 was showing voltage distribution at 288 ms for partner acceptance condition. The white circle highlighted the location of channel E6. (C) Scalp voltage distribution was on the atlas head model. (D) Source estimation of C2 using LORETA was showed on brain cortex. (E) Source data was displayed and projected onto MRI slices. The area within the green border represented the anterior cingulate cortex.

Figure 5

C3 component properties. (A) Component mean waveforms were at occipital sites at electrode E90 for all conditions. (B) Topography map of C3 was showing voltage distribution at 164 ms for partner acceptance condition. (C) Scalp voltage distribution was on the atlas head model. (D) Source estimation of C3 was showed on the brain cortex. (E) Source data was displayed and projected onto MRI slices. The area within the green border represented the visual cortex.

Figure 6

Experimental effects for each component and condition. Amplitude from each subject and condition was plotted as a gray dot and the mean amplitude was indicated as a whit line. The standard error (SEM, 95% confidence interval) and standard deviation (SD) were sub-plotted with white lines as boxes. One-way ANOVA was used to test statistical significant (^*P < 0.05) between conditions.