IntroductionPsychopathy is a personality disorder whose main diagnostic characteristics include increased courage, affective superficiality, insensitivity and poor behavioral inhibition. The actions of psychopaths often come at a high cost to society and its citizens, and their empathy deficit is one reason why psychopaths can be so effectively destructive in many people's lives. The importance of understanding this deficit cannot be overstated. If psychopathic empathy deficit could be understood, treatment would likely not only expand in variety but also in effectiveness. Therefore, this research could provide a possible remedy to a costly social problem resulting not only from the actions of criminal psychopaths but criminals in general. However, the neural mechanism underlying this empathy deficit is still poorly understood. A common hypothesis to explain empathic deficit is the inability to process emotional stimuli, particularly expressive faces, in psychopaths. Kawasaki et al. (2001) explored the relationship between emotional sensory stimuli and the prefrontal cortex. They examined the response of neurons in a 48-year-old epileptic patient using depth electrodes to record the activity of neurons. They found a short latency to aversive stimuli in the ventral prefrontal cortex. The inability of individuals with a high level of psychopathy to process emotional stimuli can be further explored by assessing how they respond to specific emotional stimuli, particularly facial expressions. Decety et al. (2014) extensively analyzed the processing of facial expressions in individuals with high levels of psychopathy using functional magnetic resonance imaging (fMRI). Participants observed scary, sad, happy, and distressed dynamic facial expressions. They found that individuals with high PC... middle of paper... otional faces, is a primary factor in the empathy deficit that is characteristic of a diagnosis of psychopathic personality disorder. The specific mechanism can be determined by the timing of activation of BA44, the amygdala, and the PFC. If early activation of BA44 is found, this will indicate that an empathy deficit most likely results from a problem with the mirror neuron system, and since an individual with a high level of psychopathy is unable to process faces correctly, the connection between emotional faces and the amygdala will be more evident. be broken and decreased amygdala activity will result. The PFC uses emotional input from the amygdala to make decisions, so a deficit in the BA44 amygdala will result in callous decisions that ignore fear responses in other humans. This would explain how psychopaths are able to ignore individuals who are in pain or fear when most humans cannot.