Neurophysiological profiling of emotional and cognitive states in healthy individuals

Emotions play a fundamental role in shaping human cognition and behavior, profoundly affecting the way we perceive, evaluate, and respond to our environment. Although extensive research has examined how the brain processes visual emotional stimuli, less is known about neural mechanisms related to emotional imagination and the processing of varying emotional and cognitive states. This study aims to address this gap by looking into brain activity using Electroencephalography (EEG) in response to emotional auditory inputs. Thirty-one healthy participants listened to neutral, positive, negative, and abstract spoken words and were instructed to imagine or feel these conditions while their brain activity was recorded. Event-Related Potentials (ERP) and Fast Fourier Transform (FFT) analyses were used to examine immediate and frequency-based neural responses. Our findings show that instructions to feel negative emotional words caused increased mean amplitudes, particularly in fronto-central areas, during the 250-350 ms timeframe compared to neutral conditions. For the 450-700 ms timeframe, negative emotions elicited stronger mean amplitudes than abstract stimuli over parietal electrodes. The FFT analysis showed increased beta and alpha power during negative emotional processing, while gamma, theta, and delta waves were not significantly affected by task condition. Overall, the results indicate that emotional words engage distinct neural processes during imagination. Notably, negative stimuli elicited more pronounced activity, which could be interpreted as enhanced cognitive-affective elaboration associated with internally generated imagery. The study provides new insight into how emotional states influence brain function in the context of internally generated emotional imagery.