Why Humans Are Hard-Wired to Place Blame

As a species, humans have survived and evolved in part due to the ability to cooperate and to enforce social norms. Researchers have discovered that the dorsolateral prefrontal cortex (DLPFC) plays a selective, causal role in the process of placing blame and punishing those who violate social norms. The study was performed by Joshua Buckholtz, PhD, of the Department of Psychology at Harvard University, and several colleagues. The results were published online in Neuron, on September 16, 2015.

Previous research had suggested that the DLPFC plays a role in how humans make norm-based judgements, however, the authors of this study say, “Norm enforcement is not a single, unitary cognitive process, but rather comprises a range of distinct subcomponent of processes.” Studying only how the DLPFC works within the larger construct of blame and punishment has been difficult.

The area of the DLPFC that has been observed as being engaged during norm enforcement is also active during working memory, analogical reasoning, and rule based decision making. The researchers began this study with the hypothesis that the DLPFC integrates various streams of information such as the amount of harm caused by an action and how culpable the person violating the social norm is in order to arrive at an “array of context-specific punishment response options.”

In order to test their hypothesis, the researchers used brain stimulation and neuroimaging. They presented participants with scenarios that only required judgements about blameworthiness, and scenarios that required a decision about punishment. They recruited 66 healthy volunteers and in two separate sessions asked them to make punishment and blameworthiness decisions regarding a series of scenarios.

The results of the study, “confirms that assessing blameworthiness and assigning punishment are cognitively distinct processes,” and that the DLPFC is selective for assigning punishment. The researchers believe that the results of their work provide a “window into the cognitive mechanisms that underlie paradigmatic decisions in the criminal justice system.” Although other species punishes violations of norm enforcement, humans have used cooperation to achieve a high level of evolutionary stability, and this study demonstrates a bit of how the human brain integrates information in order to cooperate.