Magnetic Brain Stimulation Can Change How Punishments Are Imposed

A recent study by researchers at Vanderbilt University and Harvard University provides “deeper insights into how people make decisions relevant to law, and particularly how different parts of the brain contribute to decisions about crime and punishment,” according to one of the co-authors, Owen Jones.  The study, ”From Blame to Punishment: Disrupting Prefrontal Cortex Activity Reveals Norm Enforcement Mechanisms,” found that the dorsolateral prefrontal cortex of the brain is “crucial to punishment decisions.”

Repetitive transcranial magnetic stimulation (rTMS) was used on that brain area to briefly alter the brain activity in 33 volunteer men and women; an additional 33 men and women received a placebo. The participants were asked to make decision concerning punishment and blameworthiness in various crime-scenarios; the scenarios involved harm ranging from low property loss to death, and also had different levels of culpability of the suspects.

When deciding punishment for the suspects, those volunteers who had received the rTMS “chose significantly lower punishments for fully culpable suspects,” especially in cases with low to moderate harm scenarios.  The results suggested to the researchers that “impaired integration of signals for harm and culpability” was the cause for the effect.  Joshua W. Buckholtz, another of the co-authors of the study, stated that “punishment requires that people balance these two influences [harm and culpability], and the rTMS manipulation interfered with this balance.”

Jones, a professor of law at Vanderbilt University and the director of the MacArthur Foundation Research Network on Law and Neuroscience, said he hoped “that these insights will help to build a foundation for better understanding, and perhaps one day better combatting, decision-making biases ion the legal system.”

Sources:, “How your brain decides blame and punishment, and how it can be changed,” September 16, 2015: releases/2015/09/150916133655.htm

Study Finds Ancestral Background Discernible From Fingerprints

A recent proof-of-concept study examined the Level 1 (pattern types and ridge counts) and Level 2 details (bifurcations) of the right index-fingerprints of 243 Americans to determine whether there were identifiable traits related to either sex or ancestral background.  The participants were 61 African American women, 61 African American men, 61 European American women, and 60 European American men.  No significant variations were found between men and women, but the researchers found “significant differences” in Level 2 details between those of European American and African American backgrounds.

"A lot of additional work needs to be done, but this holds promise for helping law enforcement," said Ann Ross, senior author of the study and professor of anthropology at North Carolina State University.  "And it's particularly important given that, in 2009, the National Academy of Sciences called for more scientific rigor in forensic science -- singling out fingerprints in particular as an area that merited additional study.”

Sources: Sources:  North Carolina State University, "Ancestral background can be determined by fingerprints." ScienceDaily, 28 September 2015: /10.1002/ajpa.22869/abstract;jsessionid=762EB2ABCCABE45B97D973E35909A59A.f04t04

by Neil Leithauser

Associate Editor