The Roles of Emotion and Reason on Moral Judgments - A Cognitive Neuroscience Perspective

            

In the field of cognitive science, there exist two opposing models for the roles of emotion and reasoning in moral judgment. The Humean view asserts that emotions determine the judgment and reason – a slave to emotion – functions as a tool for post hoc rationalization. The Jeffersonian view argues that both emotions and reason determine moral judgments. The two articles in this paper each support one of these opposing models. Wheatley and Haidt (2005) found their data to be consistent with the Humean model while Koenigs, Young, Adolphs, Tranel, Cushman, Hauser and Damasio (2007) found their data consistent with the Jeffersonian model. An analysis of these articles reveals that the findings in Wheatley and Haidt (2005) can be viewed as consistent with the Jeffersonian model and Koenigs et al. (2007) simply builds upon those findings. These studies show that both emotions and reason influence moral judgment.

Study 1
Wheatley and Haidt (2005) hypothesized that hypnotically induced disgust would increase the severity of moral judgments. Half the subjects received a posthypnotic suggestion to feel disgust when reading the word often and the other half when reading the word take. They then rated how morally wrong and how disgusting moral transgressions in vignettes were. The subjects were presented with one of two versions of each vignette: one which contained the word take and the other the word often. Participants rated vignettes as more disgusting and morally wrong when the disgust word was present than when it was absent, thus supporting the hypothesis.

To ensure that disgust influenced moral judgments and did not simply make all ratings more negative, Wheatley and Haidt (2005) conducted a modified version of the previous experiment containing a third (control) rating in which the subjects judged a non-transgression item related to the vignette. There was no significant difference between the ratings of items when the disgust word was present than when absent, suggesting that disgust did not make all ratings more negative. However, disgust did make moral judgments more severe even in the case of the “Student Council story,” which contained no moral transgression; when questioned on this particular story, experimenters reported the puzzled subjects answering with post hoc rationalizations. This is consistent with a model in which intuition and emotions determine moral judgments.

Study 2
Koenigs et al. (2007) investigated neurologically how damage to emotion-related areas of the brain influence moral judgment. There were three types of subjects, all with reasonably intact intellects. The first were normal comparison subjects (NC). The second were patients with adult-onset damage to the ventromedial prefrontal cortex (VMPC), a brain region associated with generation of social emotions. The third were brain-damaged comparison (BDC) patients with lesions excluding emotion-related regions of the brain. The subjects either endorsed or rejected actions in fifty hypothetical scenarios. Scenarios were classified as non-moral, impersonal or personal. Personal scenarios were distinguished for their higher emotional salience, determined by a separate group of neurologically normal subjects. Personal scenarios were then separated into high-conflict and low-conflict scenarios based on the level of agreement within and between NC and BDC groups. These high-conflict scenarios were assumed to feature intense competition between utilitarian considerations and an emotional aversion to harming others, a level of competition not present in the low-conflict scenarios. VMPC patients differed from NC and BDC patients only in personal high-conflict scenarios in which they endorsed actions more often than the other groups. Other scenarios elicited reasoned responses from all groups, as demonstrated by the fact that the VMPC group did not differ from the others. The divergence in the personal high-conflict scenarios demonstrates that emotions began to overpower reason in the BDC and NC groups, but not in the VMPC group.

Resolving the "Opposing" Views
Although Wheatley and Haidt (2005) claimed to support a model for moral judgment in conflict with that of Koenigs et al. (2007), it can be argued that Wheatley and Haidt (2005) actually provides further justification for the model proposed by Koenigs et al. (2007). By hypnotically inducing disgust, Wheatley and Haidt (2005) tremendously increased the emotional salience of the vignettes. In this manner, that emotional impact is similar to that found in personal high-conflict scenarios in Koenigs et al. (2007). Both articles would agree that in such scenarios which elicit a strong emotional response, that emotion determines the moral judgment. Thus, Koenigs et al. (2007) simply builds upon the findings of Wheatley and Haidt (2005) to demonstrate that in cases of lower emotional intensity (impersonal scenarios), reason has far more influence. These articles can be reconciled to support the Jeffersonian model in which both reason and emotions influence judgment.

Reconciling the two articles by viewing the emotion elicited by the disgust word in Wheatley and Haidt (2005) as similar to that elicited by personal high-conflict scenarios in Koenigs et al. (2007) contributes much to an understanding of the basis for moral judgment. It provides data consistent with the Jeffersonian model in which both emotions and reason influence moral judgments. In scenarios where the emotional response is minimal, reason dominates as opposed to cases in which the emotional response is strong where reason becomes a slave to emotion.

The Nose (really) Knows

Last semester, at the Kids Judge Neuroscience Fair (a science fair put on by Penn students and judged by students from various neighboring elementary schools), an experiment was titled “Nose Knows.” I didn’t pay much attention to the title of this exposition, and disregarded it just a quirky, alliterative way to catch the attention of our young judges. Up until recently, I hadn’t given this exposition, or its title, much thought.

Last week in one of my classes, I was blown away by the information presented by Dr. Johan Lundstrom, our guest lecturer. Dr. Lundstrom explained how our sense of smell, probably the sense that most of us consider to be the least important, plays a highly underestimated role in our lives. Our sense of smell participates in everything from mate choice to memory and emotional response. Also, surprisingly to me, it is not uncommon for a physician to use his or her sense of smell as a diagnostic tool.

Research on olfaction is continually helping scientists and society to understand the role of the sense of smell in our lives. As science and technology continue to advance, it is likely that we will greater perceive and appreciate this trivialized sense. Who knows, maybe one day Google's April Fool's joke will actually be a reality!

-Beatriz Gadala-Maria

Challenges to Free Will

Recent studies have begun to challenge the notion of free will. Some people argue that free will exists, while others believe it may be a carefully constructed illusion. In order to better understand this concept, cognitive scientists have tried to study human agency by having subjects perform simple motions. One study identified the timing and activation of the brain regions that predetermine conscious intentions. A separate group of researchers focused on the sense of volition that precedes movement itself. In the following two studies, the experimenters use disparate methodologies and techniques to advance the study of individual autonomy.

Study 1:
Soon, Brass, Heinze, and Haynes aimed to elucidate the timing and location of brain region activation that predetermines conscious intention. The subjects were asked to press one of two buttons with either their right or left index finger whenever they felt the urge to do so. The experimenters flashed a series of letters on a screen at 500 millisecond time intervals to determine when the subject made his or her decision. After each finger motion, the subjects reported which letter was on the screen at the time when they made their decision, giving the experimenters a quantitative measure of when the subjects consciously decided. In addition to measuring the timing of the conscious decision, the scientists used fMRI to study the patterns and amount of activity in different brain regions. They looked at the predictive patterns both before and after the subject’s conscious decision.

Soon et al. found that two specific regions in the frontal and parietal cortex provided information that could predict the outcome of the motor decision before the subject was consciously aware of making that decision. They also discovered through the fMRI that unconscious activity in the brain had been affecting the subject’s motor decision for up to 10 seconds before the decision reached consciousness.

Study 2:
In a recent study, Schneider, Houdayer, Bai, and Hallett tried to determine when the sense of volition arises in movement formulation and execution. They used EEG signals to create a predictive model after asking subjects to move their right wrists spontaneously. They could determine with an 18% false positive rate when a person was going to move their right wrist within 1.5 seconds before the movement itself. The experimenters used the model for subsequent real-time prediction sessions. As the subjects moved their wrists during these sessions, they were stopped periodically and prompted to answer two questions: “Did you feel the intention to move?” and “If not, what were you thinking about?” A green light signalled subjects to answer the questions, providing a broad range of data because it turned on either spontaneously or when the predictive model explicitly showed a subject’s intention to move.

The responses to the first question were split into four categories to differentiate between the combinations of movement and intention. “Intention” refers to the intention to move as shown by the brain activity while using the predictive model. 43% were “movement with intention,” 13% were “movement without intention,” 12% were “no movement with intention,” and 32% were “no movement without intention.” The fact that 12% had the intention to move but did not end up moving may be a manifestation of free will because it displays the human capability to stop a movement, despite the brain’s supposed intention to move. There is not yet a conclusive explanation for this phenomenon. Additionally, the experimenters categorized the answers to the second question into subjects of thought which pertained to subjects like the task, light, or movement. The results showed that the participants could be thinking about something non-movement related, even while the brain was preparing to make a voluntary movement.

Study 1 and Study 2:

The results of Schneider et al. and Soon et al. each illuminated potential shortcomings that could have gone unnoticed had these articles not been read in conjunction with one another. The first questionable discrepancy pertains to the timing of the predictions. Soon et al. showed that the intention to move could be seen as far as 10 seconds before the movement itself. At successive points in time and, consequently, during different stages in motor planning, people could acquire varying types of information. Despite this finding, Schneider et al.’s predictive model only aimed to measure the intention to move 1.5 seconds in advance of an actual movement. By focusing solely on the last stages of motor planning, Schneider et al. does not provide as complete of an understanding of the brain activity leading up to movement as Soon et al. Reading Soon et al. makes the reader wonder if the results would have been different or if the predictive model would have been more accurate had the experimenters in Schneider et al. used information from more than 1.5 seconds before movement.

Additionally, reading Schneider et al. illuminated an assumption that is fundamental to Soon et al’s experimental design: the assumption that movement is always intentional. In “Unconscious determinants of free decisions in the human brain,” the possibilities of “movement without intention” or “no movement with intention” simply do not exist. The right and left index finger movements are always associated with an explicit “urge.” Reading Schneider et al. after Soon et al. highlights the important point that intention and movement are not always coupled.

Both of these studies clearly show that voluntary movement can be predicted with reasonable accuracy using tools like fMRI and EEG. While they do conclusively address the idea that there are unconscious determinants that affect decisions, one shortcoming that pertains to them both is that they focus solely on simple motor movements. When people question the notion of free will, their concerns more closely relate to conscious, complex decision-making than to trivial finger and wrist motions. Focusing on simple motor movements is not enough to answer the loftier question about whether or not free will is really limited. Further research is required to better understand human autonomy and the existence of free will, particularly in the context of thoughtful deliberation.