The Ventromedial Prefrontal Cortex's role in Moral Judgement

Article: Selective deficit in personal moral judgment following damage to ventromedial prefrontal cortex
Authors:Elisa Ciaramelli, Michela Muccioli, Elisabetta Làdavas, and Giuseppe di Pellegrino
Published in: Soc Cognitive and Affective Neuroscience. 2007 June; 2(2): 84–92.

The ventromedial prefrontal cortex has been known to account for aggressiveness, lack of concern for social and moral rules, and irresponsibility. The researchers tested seven brain lesion patients and twelve healthy (control group) patients to see how participants made decisions about the appropriateness of personal and impersonal moral dilemmas. From what I understand, the difference between the two dilemmas has to do with actually harming another person directly. As the article describes, it is the difference between pushing someone off a ledge in order to save five other lives and flipping a switch that causes one person’s death but saves five others. The personal dilemma is coming in contact with another person, while the impersonal dilemma only requires the flipping of a switch. Take note that personal dilemmas cause more emotional strain on the actor.
The researchers presented patients with 3 screens. The first screen described a scenario, the second screen asked if the action was appropriate or inappropriate, and the third screen asked the participant to recall something about the scenario to ensure that he or she remembered enough about the situation in order to make a decision.
The results found that patients with ventromedial prefrontal lesions approved more personal moral violations compared to the control group, and did so more quickly. Interestingly, the control group and patients with brain lesions did not show much variation on deciding the appropriateness of impersonal moral dilemmas. The article claims that the ventromedial prefrontal cortex “allows individuals to endure sacrifices now in order to obtain benefits later.” In that case, brain lesion patients are more inclined to think ahead. From one of my other posts, I have learned that the ventromedial prefrontal cortex plays a large role in empathy. If morality and empathy are related, brain lesion patients would be at a deficit on both fronts. Healthy subjects would have an easier time assessing how their moral actions would make them feel.

The Role of TMS in Studying Facial Signals

Article:
“Dissociable roles of the human somatosensory and superior temporal cortices for processing social face signals”

Authors: Gilles Pourtois, David Sander, Michael Andres, Didier Grandjean, Lionel Reveret, Etienne Olivier and Patrik Vuilleumier

Published by: EuropeanJournalofNeuroscience,Vol.20,pp.3507–3515,2004

This article examines the role of the right somatosensory cortex and the right superior lateral temporal cortex in recognizing emotional expression, either fear or happiness, and shift in eye gaze. The researchers used single pulse transcranial magnetic stimulation over these two areas of the brain while participants completed the given task. The participants, who were all healthy, had to look at two successive pictures depicting people with different emotions and directions of eye gaze. They were then asked to press a button indicating whether the two pictures showed the same emotion and the same eye gaze. The pictures only showed people displaying happy or fearful emotions and eye gazes were only shifted either direction by 30 degrees.
The results concluded that TMS over the somatosensory areas interfered with recognizing fear and that TMS over the superior temporal cortex interfered with the perception of gaze shifts, meaning that the two different areas in the brain have unique functions. The experiments also found that TMS slowed down recognition of fearful expressions versus recognition of happy expressions. I thought this was a very interesting finding. The article suggests that happiness is easier to detect because it can be identified by one universal facial signal, a smile.
After reading the article, I wonder why the researchers chose to test these two emotions, as opposed to “opposite” emotions like happiness and sadness. I also wonder how TMS would affect the recognition of other emotions, especially anger, since I think that is very easy to detect. I also found it interesting that the two successive pictures were always different genders. What is it about the differing genders that the researchers were looking for? This makes me question whether being able to identify with the person on the picture may have something to do with recognition of social cues. Perhaps if the participant knew the person in the picture the results would change. The most interesting concept for me was that recognizing fear in other people uses a different part of the brain (somatosensory areas) than recognizing and responding to fear in one’s self, which we have learned involves using the amygdala.

Brain Lesion and Empathy

Article:

“Characterization of Empathy Deficits following Prefrontal Brain Damage: The Role of the Right Ventromedial Prefrontal Cortex” was written by S.G. Shamay-Tsoory, R. Tomer, B.D. Berger, and J. Aharon-Peretz and published by The Journal of Cognitive Neuroscience.  

This article examines how brain lesion in the prefrontal cortex affects the ability to empathize with others.  Research thus far has found that various parts of the brain work together in empathy, but that the right ventromedial (VM) prefrontal cortex plays the biggest role.  The researchers tested brain lesion patients and emotional processing through two tasks: participants were asked to identify seven different emotions depicted by people in thirty-five pictures and to listen to sentences and identify the person’s emotion by analyzing their intonation of speech.

Although VM lesion patients may understand a social situation, they may not necessarily understand the emotional outcome.  This inability causes them to respond inappropriately, not empathetically.  Other effects included decreased self-awareness, social judgment, ability to make decisions, and loss of insight.

Identifying others’ emotions is crucial in social interaction.  It makes sense that being unable to judge what another person is feeling based on his or her facial expression or tone of voice would cause someone to act out the social norm.  Knowing what an individual is looking to get out of the interaction and his or her behavioral intent is crucial to identifying and empathizing with the other person, or in some cases, consciously deciding not to. I have always been interested in why some people are more socially adept than others, so I wonder if this research can go further to make conclusions about empathy in people without brain lesions.  Perhaps the size of the VM could affect social ability?

region highlighted: ventromedial prefrontal cortex

 

shows damage to right ventromedial prefrontal cortex