Psychopathic individuals appear to be hyporeactive to emotional stimuli. In other words, the emotional parts of the brains do not react as strongly to emotional stimuli as the same parts of the brain in healthy people and even in non-psychopathic prisoners. Likewise, a large body of literature shows that psychopaths have difficulty processing emotional information. Compared to non-psychopathic criminals, they are less able to identify emotions as expressed in vocal tone, facial expression, or spoken sentences. Moreover, they may be particularly insensitive to sadness. Also, the two halves of their cortex, the left and right hemispheres, are not well coordinated during cognitive tasks, and the left hemisphere may be less active than is typical for most people. This suggests that the emotional processes of the right hemisphere are not well coordinated with the verbal processes of the left hemisphere. This difficulty making sense of emotion may relate to the lack of empathy that is characteristic of psychopaths.