The phenomenon of inner speech and the related concept of internal utterance are actively studied in psychology, psycholinguistics, and cognitive neuroscience. However, there is no unified approach to defining these terms and their relationship. The verbalization of action words presents a unique challenge in determining the extent to which purely verbal processes are engaged compared to mental imagery of the corresponding actions. This distinction is crucial for developing machine learning models to classify such action-command words. The present study aims to identify the psychophysiological mechanisms underlying the perception and internal verbalization of action words, as well as the mental representation of the associated actions. Event-related potentials (ERPs) were used to comparatively investigate the neural correlates of internal prosody and action representation. Statistically significant differences were found between internal prosody and action execution representation in ERP components at the N140 and N400 latencies across multiple electrode sites. Significant differences were also observed in the perception and mental recitation of action words. Distinct ERP components were identified for the perceptual and internal utterance processes. Furthermore, the findings revealed significant differences in ERP components between the perceptual process and the prosody task, as well as between internal utterance and mental representation of action performance, in various cortical and subcortical brain structures. These results contribute to the understanding of the psychophysiological mechanisms underlying the perception and internal pronunciation of action words, and have implications for the development of brain-computer interfaces.