Influence of Emotional Context on the Perception of Neutral Stimuli: An ERP Study

Poster Session A - Saturday, April 13, 2024, 2:30 – 4:30 pm EDT, Sheraton Hall ABC

SHIH-KUEN CHENG¹ (skcheng@cc.ncu.edu.tw); ¹National Central University

This study investigates how emotionally neutral items are perceived within negative and positive emotional contexts, exploring two potential outcomes: assimilation into the context's valence or contrast against it. We focused on the examination of Event-Related Potentials (ERPs) elicited by neutral pictures presented alongside either negative or positive images. Our findings revealed that emotional pictures in both contexts generated significant Late Posterior Positivity (LPP) when compared to neutral images. Notably, the LPP effect was more pronounced and enduring for negative pictures. A differential analysis, involving a comparison wave generated by subtracting the ERPs of neutral pictures in positive contexts from those in negative contexts, showed an early LPP akin to that induced by positive pictures in positive contexts. However, over an extended duration and range, it resembled the LPP triggered by negative pictures in negative contexts. These results suggest that the emotional impact on neutral stimuli is not governed by a singular process but rather by a dual mechanism of assimilation and contrast. Further analysis using Independent Component Analysis (ICA) identified distinct source components of these ERPs, varying in response to positive and negative pictures. These components reflect the nuanced differentiation of neutral pictures under different emotional valences, corroborating the observed ERP findings. This study sheds light on the complex interplay between emotional context and neutral stimuli perception, highlighting the roles of both assimilation and contrast mechanisms.

Topic Area: EMOTION & SOCIAL: Emotion-cognition interactions