The paper revises the motor theory of speech perception, initially proposed to explain early findings on synthetic speech, to incorporate recent research and relate it to other perceptual modes. The revised theory posits that phonetic information is perceived through a specialized 'module' that detects the intended gestures of the speaker, which form the basis for phonetic categories. This module is designed to handle the unique but lawful relationship between gestures and acoustic patterns, allowing for the perception of phonetic structure without translation from auditory impressions. The theory emphasizes the link between perception and production, suggesting that this link is innately specified and not a learned association. The authors argue that speech perception is fundamentally different from other perceptual processes, such as auditory localization, due to the specific relation between gestures and acoustic signals in speech. They also discuss the competition between the phonetic and auditory modules and provide experimental evidence supporting the theory, including the multiplicity and variety of acoustic cues, segmentation in sound and perception, and the role of coarticulation in shaping phonetic perception.The paper revises the motor theory of speech perception, initially proposed to explain early findings on synthetic speech, to incorporate recent research and relate it to other perceptual modes. The revised theory posits that phonetic information is perceived through a specialized 'module' that detects the intended gestures of the speaker, which form the basis for phonetic categories. This module is designed to handle the unique but lawful relationship between gestures and acoustic patterns, allowing for the perception of phonetic structure without translation from auditory impressions. The theory emphasizes the link between perception and production, suggesting that this link is innately specified and not a learned association. The authors argue that speech perception is fundamentally different from other perceptual processes, such as auditory localization, due to the specific relation between gestures and acoustic signals in speech. They also discuss the competition between the phonetic and auditory modules and provide experimental evidence supporting the theory, including the multiplicity and variety of acoustic cues, segmentation in sound and perception, and the role of coarticulation in shaping phonetic perception.