The study by Ulf Dimberg, Monika Thunberg, and Kurt Elmehed investigates unconscious facial reactions to emotional facial expressions. Using the backward-masking technique, the researchers prevented participants from consciously perceiving 30-ms exposures of happy, neutral, and angry faces, which were immediately followed by neutral faces. Despite the unconscious exposure, participants exhibited distinct facial muscle reactions corresponding to the masked emotional stimuli. Specifically, the happy faces evoked increased activity in the zygomatic major muscle, while the angry faces evoked increased activity in the corrugator supercilii muscle. These findings suggest that both positive and negative emotional reactions can be evoked unconsciously, indicating that important aspects of emotional communication can occur on an unconscious level. The study supports the idea that facial expressions are controlled by biologically based affect programs and that these reactions can be triggered independently of conscious cognitive processes.The study by Ulf Dimberg, Monika Thunberg, and Kurt Elmehed investigates unconscious facial reactions to emotional facial expressions. Using the backward-masking technique, the researchers prevented participants from consciously perceiving 30-ms exposures of happy, neutral, and angry faces, which were immediately followed by neutral faces. Despite the unconscious exposure, participants exhibited distinct facial muscle reactions corresponding to the masked emotional stimuli. Specifically, the happy faces evoked increased activity in the zygomatic major muscle, while the angry faces evoked increased activity in the corrugator supercilii muscle. These findings suggest that both positive and negative emotional reactions can be evoked unconsciously, indicating that important aspects of emotional communication can occur on an unconscious level. The study supports the idea that facial expressions are controlled by biologically based affect programs and that these reactions can be triggered independently of conscious cognitive processes.