Analyzing Neural Activity from Emotion-triggering Stimuli in Sociopaths and Psychopaths

          It is commonly known that individuals who are considered psychopaths or sociopaths are incapable of possessing empathy or compassion towards others or cannot express fear or remorse. Since these types of individuals do not have emotional responses to pain, suffering, or violence, they are the ones that can cause the greatest harm to other people. Many criminals and murderers fall under the category of psychopath or sociopath. Though many behavioral indicators have been identified to determine whether an individual has psychopathic or sociopathic tendencies, recent research has shown that using neuroscience and measuring neural activity in the human brain can provide a more accurate assessment of an individual’s personality disorder. 

        According to the article “What Can Neuroscience Tell Us About Evil?”, Richard Brandt discusses how researchers and scientists have figured out how to measure the presence of a personality disorder in an individual. This was done with the use of functional magnetic resonance imaging, or an fMRI scan. Participants in the study were shown gruesome, violent, and gory images, and as they saw each image the fMRI would indicate which region of the brain indicated activity. The brain scans of normal individuals indicated neural activity in the amygdala, a region in the brain responsible for generating fear and empathy. In the psychopathic and sociopathic participants, however, these regions indicated little to no activity. Other research that had been conducted using fMRI indicated that the frontal cortex, a neural region responsible for reasoning, also lacked activity in psychopathic and sociopathic participants. Some theories propose that the amygdala and the frontal cortex work together and that there is a direct relationship between the amount of activity in the amygdala and the frontal cortex. 

    Similarly to this research, the research conducted by Ian Kahrilas et al. measured neural responses to emotional stimuli. Rather than using an fMRI scan like in the previous research mentioned, this study used event-related potentials or ERPs that are measured using an electroencephalograph (EEG). fMRI scans rely on slow changes in blood flow so it is difficult to determine how emotional processing occurs over time. Contrastingly, using ERPs allows for the identification of electrocortical activity almost immediately after the stimulus is present and continues to measure it over time to determine how emotional processing unfolds in the regions of the brain. The results of this research indicated that a wide range of ERP components is in fact, sensitive to emotion.

    To conclude, the findings of each of these studies can be of significant use to diagnose and identify individuals with personality disorders such as those who are psychopaths or sociopaths. Using both fMRI and ERPs can not only help patients get diagnosed, but it can also allow for individualized medicine that can provide better treatment for individuals with more moderate or more severe personality disorders.

Sources:

Brandt, Richard. “What Can Neuroscience Tell Us about Evil?” MIT Technology Review, MIT Technology Review, 2 Apr. 2020, www.technologyreview.com/2007/04/24/99554/what-can-neuroscience-tell-us-about-evil/. 

Foti, Dan, et al. “Differentiating Neural Responses to Emotional Pictures: Evidence from Temporal-Spatial PCA.” Psychophysiology, vol. 46, no. 3, 2009, pp. 521–530., doi:10.1111/j.1469-8986.2009.00796.x.