Day 4: A Poster on the Neuroscience of Ethics

trolleyAlthough I presented my poster this morning, I’m not going to talk about it here. Rather, I’m going to briefly report and summarize an interesting poster I saw yesterday by graduate student Bradley Thomas, who is in Daniel Tranel‘s lab at the University of Iowa.

The poster was titled The Self-Other Bias in Moral Judgment is Insensitive to Ventromedial Prefrontal Damage. Thomas reported on study that aimed to examine whether the ventromedial prefrontal cortex (VMPFC) is crucial for creating moral judgments about both Self and Other dilemmas, whether the self-other bias of moral judgments about these dilemmas can be replicated, and whether this self-other bias is sensitive to VMPFC damage. This work comes right off the heels of some other writings in this domain, including a recent paper in Neuroethics by Thomas Nadelhoffer and Adam Feltz. Some of Tranel’s previous work with others such as Antonio Damasio and Marc Hauser support the notion that the VMPFC damage increases utilitarian judgments.

The authors recruited 3 groups for experimental study: a) neurologically ‘normals’; b) brain damage comparison; and c) adult-onset VMPC-lesions. They created a novel battery of 12 Self and 12 Other high-conflict personal moral dilemmas, based on the dilemma of the trolley problem. Typically when presented with the trolley-problem thought experiment, participants will endorse a simple utilitarian end – i.e., they will believe it is morally permissible to flip the switch (or pull the lever, depending on the version) to save 5 individuals and the trolley to run over 1 person.

Most notably among their findings was that  individuals with VMPFC damage were most likely to endorse a utilitarian outcome in both Self and Other dilemmas. Accordingly, as the title suggests, the Self-Other bias was insensitive to VMPFC lesions. Thomas and his co-authors suspected that the bias does not appear to be created by the VMPFC and other complex emotional processing. The authors hypothesize that bias in moral judgment may be due to more basic psychological processes, such as an increased aversion to causing self-harm versus another person causing that harm. I wonder, despite the VMPFC damage, if the somatic marker hypothesis may be somewhat relevant here…

I am really looking forward to seeing more work of this kind in the future.