"Good God!" he cried, "can it be, can it be, that I shall really take an axe, that I shall strike her on the head, split her skull open... that I shall tread in the sticky warm blood, blood... with the axe... Good God, can it be?"- Fyodor Dostoevsky, Crime and Punishment, Ch. 5
A new fMRI paper in Neuron (Buckholtz et al., 2008) claims to have discovered the neural correlates of evaluating another person's crime and deciding on the appropriate sentence, in emulation of judges and juries meting out third-party punishment (Fehr & Fischbacher, 2004).
On the other hand, the rotating "freak show" guests on the Jerry Springer Show mete out second-party punishment,1 which is generally harsher (in midget fights and certain economic games, at least).
Here’s the great new insight of the paper, according to the Preview by Johannes Haushofer and Ernst Fehr:
Thus, the study of Buckholtz makes a valuable contribution in that it illustrates that third-person judgment situations, such as those used in their study, may rely on similar neural mechanisms as two-person economic and social exchanges. While it is difficult to draw reverse inferences about mental states based on brain activation (Poldrack, 2006),2 one might speculate, based on this new study, that the mental processes motivating judicial verdicts involve the suppression of prepotent emotional reactions in favor of impartial and objective verdicts.[NOTE: aren’t you just marveling at this grand new insight from fMRI? Like we didn’t already know that judges and jurors must put aside their emotionally-driven desire for revenge when coming to an impartial verdict.]
Thus, this new result might, if confirmed by future studies, elucidate the neural source of judicial impartiality.All right, let's go back to the beginning. Or to the Methods, at least. One of the experimental tasks was to determine whether the perpetrator of a given hypothetical crime was responsible for his actions. There were two versions of the same basic crime scenarios with the details of Responsibility versus Diminished Responsibility counterbalanced across the two sets (e.g., compare #3 and #32 below). Half of the participants read Set 1, the other half read Set 2. Some of the infractions were minor (#7, #22), but some were crimes of the most heinous sort, whether intentional (#3) or unintentional (#27, #32). Thus, the severity of the crimes was matched across the experimental conditions as well. Below are some examples of the stimuli, taken from the Supplementary Materials.
Responsibility Scenarios
3) John develops a plan to kill his 60-year-old invalid mother for the inheritance. He drags her to her bed, puts her in, and lights her oxygen mask with a cigarette, hoping to make it look like an accident. His mother screams as her clothes catch fire and she burns to death.
7) John is parking his car in the parking lot of a local football stadium, where he plans to watch a game. In the car next to his, he sees a hat with his team logo in the back seat. Seeing that the door is unlocked, John opens the door, and takes the hat.
Diminished Responsibility Scenarios
22) John visits a local bookstore, carrying a large shopping bag with goods from another store. While the store clerk is preoccupied with inventory, another customer, hoping to use John unwittingly in a theft, sneaks a book into John’s shopping bag. Without realizing what has happened, John walks out without paying for the book.
27) A brain tumor is causing increasingly erratic, violent, and callous behavior in John.
32) Unbeknownst to John and his doctors, his new prescription interacts with his other medications to induce severe acute psychoses. During that interaction, John returns home to his 60-year old invalid mother, who he has always adored. John lights her oxygen mask with a cigarette, and watches as his mother catches fire, screams, and burns to death.
No Crime Scenarios [control condition]
47) The manual to John’s new car states: “The oil must be changed no less frequently than every 4,000 miles.” John reads the manual and is aware of what it says. However,
48) John and his best friend have played golf together for more than ten years. They used to be evenly matched, but recently John’s friend has consistently outplayed him. Growing frustrated, John responded by taking private golf lessons from the local pro. The next time John played against his friend, he soundly beat him.
Participants rated each scenario on a scale from 0–9, according to how much punishment they thought John deserved, with “0” indicating no punishment and “9” indicating extreme punishment. Punishment was defined for participants as “deserved penalty.”. . .Following the scanning session, participants rated the same scenarios along scales of emotional arousal and valence. They first rated each of the 50 scenarios (presented in random order on a computer screen outside the scanner) on the basis of how emotionally aroused they felt following its presentation (0 = calm, 9 = extremely excited). They then rated each of the scenarios, presented again in random order, on the basis of how positive or negative they felt following its presentation (0 = extremely positive, 9 = extremely negative).The results from these rating tasks are shown below, and it's not surprising that the subjects recommended more severe punishments for the perpetrator in the Responsibility scenarios than in the Diminished Responsibility scenarios.
Figure 1 (Buckholtz et al., 2008). Punishment and Arousal Ratings for Each Scenario Type. While punishment and arousal scores were similar in the Responsibility condition, punishment scores were significantly lower than arousal scores in the Diminished-Responsibility condition. Error bars = SEM.
As for the neuroimaging results, the authors compared the hemodynamic response in the Responsibility versus the Diminished Responsibility conditions to see what brain areas might be differentially activated. Greater activity in the right dorsolateral prefrontal cortex (rDLPFC) was emphasized (Fig 2). Responses in bilateral anterior intraparietal sulcus were similar, but relegated to the Supplementary Materials.
Figure 2 (Buckholtz et al., 2008). Relationship between Responsibility Assessment and rDLPFC Activity. (A) SPM displaying the rDLPFC VOI, based on the contrast of BOLD activity between the Responsibility and Diminished-Responsibility conditions. (B) BOLD activity time courses. BOLD peak amplitude was significantly greater in the Responsibility condition compared with both the Diminished-Responsibility and No-Crime conditions.
So now we get to the interpretation that rDLPFC is suppressing emotional reactions in areas such as the amygdala, medial PFC, and posterior cingulate cortex (which were sensitive to the magnitude of punishment) in order to assign a diminished level of criminal responsibility. The problem with that reverse inference is illustrated below.
This figure was generated from entering the x, y, z Talairach coordinates from the rDLPFC focus shown above (39, 37, 22)3 into the Sleuth program (available at brainmap.org), which searched the available database of papers for matches. The resulting list of coordinates and experiments was then imported into the GingerALE program, which performed a meta-analysis via the activation likelihood estimation (ALE) method (see this PDF). The figure illustrates that the exact same region of rDLPFC was activated during tasks that assessed attention; execution, inhibition, and observation of actions; various aspects of language and perception; and especially working memory.
The authors appear to acknowledge the caveat that
the brain regions identified in our study are not specifically devoted to legal decision-making. Rather, a more parsimonious explanation is that third-party punishment decisions draw on elementary and domain-general computations supported by the rDLPFC.They also acknowledged the confound of arousal and crime severity. Nonetheless, they concluded by waving their arms around and blabbing about the evolution of the legal system:
...on the basis of the convergence between neural circuitry mediating second-party norm enforcement and impartial third-party punishment, we conjecture that our modern legal system may have evolved by building on preexisting cognitive mechanisms that support fairness-related behaviors in dyadic interactions. Though speculative and subject to experimental confirmation, this hypothesis is nevertheless consistent with the relatively recent development of state-administered law enforcement institutions, compared to the much longer existence of human cooperation.What are we to conclude from this? Since it's very late now, I'll let Jerry and Fyodor have the last words.
“We can't just have mainstream behavior on television in a free society, we have to make sure we see the whole panorama of human behavior.”- Jerry SpringerBut when all is said and done, why don't we let Jerry Fodor have the last word?
“Actions are sometimes performed in a masterly and most cunning way, while the direction of the actions is deranged and dependent on various morbid impressions-it's like a dream.”- Fyodor Dostoevsky, Crime and Punishment, Ch. 17
“It’s a thin line between clarity and pomposity.”— Psychosemantics: The Problem of Meaning in the Philosophy of Mind, p. 17.
Footnotes
1 But as Wikipedia notes, "there has been continuous debate over the actual authenticity of the fighting."
2 "...we won’t let that stop us from rampant speculation" [to paraphrase Haushofer and Fehr]. I feel like a broken record here, but reverse inference is a logical fallacy - one cannot directly infer the participants' cognitive or emotional state from the observed pattern of brain activity. Everyone should know better by now, and there should be a moratorium on such sloppy thinking. Or rather, such sloppy writing and publishing. The high-profile journals are the worst offenders, and they end up promoting the use of totally misleading headlines like this one:
Justice may be hard-wired into the human brainCall it the justice instinct. When judging the guilt or innocence of alleged criminals, our brains seem to respond as if we were personally wronged, say researchers.The "justice instinct"?? Spare me. The experiment said absolutely nothing about evolution, genetics, or "hard-wiring."
3 According to pages 932 and 938. However, page 936 and Table S1 say the coordinates are slightly different: 39, 38, 18.
References
J BUCKHOLTZ, C ASPLUND, P DUX, D ZALD, J GORE, O JONES, R MAROIS (2008). The Neural Correlates of Third-Party Punishment. Neuron, 60 (5), 930-940 DOI: 10.1016/j.neuron.2008.10.016.
Fehr E, Fischbacher U. (2004). Third-party punishment and social norms. Evolution and Human Behavior 25:63–87.
Haushofer J, Fehr E (2008). You Shouldn’t Have: Your Brain on Others’ Crimes. Neuron 60:738-740.
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