Monthly Archives: July 2009

Social Norm Psychology is a Potent Anti-violence Vaccine

ceasefire_1An ambitious anti-crime program called “CeaseFire” just released study results on its effectiveness in inner-city Baltimore and Chicago. The program is based on the idea that killing is a disease psychologically transmitted from one person to another, particularly in economically deprived areas. 

The program employs a unique psychological angle, in that it chiefly targets potential retaliators of violence rather than all potential perpetrators of violence.  An epidemiological analogy might be a program that targets potential re-transmitters of HIV instead of a much broader population.

Outreach specialists (called “violence disruptors”) are trained to use social norm pressure to target those most likely to retaliate for violence committed against them or others close to them — as if stopping the transmission of a disease before it reaches the next host.   While that’s happening, other outreach specialists work on communicating the message in schools that retaliation isn’t “cool,” thus building a climate of social norm pressure against retaliatory violence.  The program also recruits reformed violent criminals to communicate the anti-violence message.

The results of the three-year study are impressive:

— Shootings and killings dropped between 41 and 73% in Baltimore and Chicago. Of that, study authors claim that 17-35% is attributable to CeaseFire alone

— Retaliated murders dropped 100% in 5 of 8 communities

— Overall violence was statistically reduced in every community

Evaluating effectiveness of programs like this is notoriously difficult.  For example, murder rates in Chicago have been falling overall since the 1990s.  It’s a massive research challenge to tease apart the drop in violence percentage attributable to the program versus what would have occurred anyway.  No surprise then that CeaseFire has has its share of detractors (not the least of which is the National Rifle Association).

But, the underlying theory is sound: changing social norms is a powerful way to change behavior. The reason, as discussed in a study in the journal Neuron, is that there appears to be a neural network in the brain associated with social norm compliance.  Strong messaging–including messages about punishment–activates this network to varying degrees, resulting in particular behavioral responses.  It would seem that CeaseFire has been successful in communicating messages that tap into this neural apparatus, eliciting genuine behavior change.

Moving forward, I wonder if this approach can be systematized to work in any given city — sort of an anti-violence social norming franchise. As with most public initiatives, I’m sure it’ll be a question of resources and will; the science seems to be in place.  

For more information, link to the New Scientist article about the program.



Filed under About Research

Painting with Your Brain While Not Moving a Muscle

I’m excited by the new wave of brain-computer interface systems that enable ‘locked-in’ patients, such as those with ALS and paralyzing injuries, to communicate, create art, compose music and other things never before possible. The videos below demonstrate two of these systems, BrainGate and a ‘brain-painting’ interface being developed at the University of Virginia. 


Filed under Videos