Guilt And Punishment: Research Finds How Your Brain May Make Biased Decisions

Guilt And Punishment: Research Finds How Your Brain May Make Biased Decisions

Dealing with guilt and punishment is a part of civilized life. In America, the jury system determines the guilt of the accused after seeing all the evidence. After the jury decides, a judge will determine the appropriate punishment for the crime.

It turns out that the American justice system is a metaphorical way of doling out punishments. Research at Vanderbilt University has found that the processes used to assess guilt and punishment happen in different parts of your brain. This is interesting because the research suggests that one can change, and not just affect, another.

Essentially, one part of your brain might believe a person is without guilt, but another may still want to punish them. These two parts may be mutually exclusive. However, both parts need to be balanced in order for justice to be carried out in a fair way.

The report is called From Blame to Punishment: Disrupting Prefrontal Cortex Activity Reveals Norm Enforcement Mechanisms. In the study, the researchers explain that they used rTMS (transcranial magnetic stimulation) on a specific area of the brain to alter the activity using a cell phone booster. The area of the brain manipulated by the scientists is known as the dorsolateral prefrontal cortex.


The experiment included 66 volunteers. The volunteers were given scenarios of crimes that ranged from property destruction to death. The group was also told how responsible the suspect was for the crime.

Then, 33 people were given active rTMS while the other half were given a placebo. The subjects then had to decide what punishment to enforce on the criminals in the scenarios. These scenarios ranged from threats to home security, as well as assaults committed by the felons.

The results saw that those who had their brains manipulated with rTMS chose smaller, less-impactful punishments. This was even true for suspects that were fully responsible for the crimes in the scenarios.

In the cases where the accused was completely guilty but only committed a small crime, many of the subjects chose to award only small punishments.


The results of the study suggested that the disruption to this area of the brain changed how the subjects made their decisions. This was despite the fact that the information did not change.

According to this research, deciding suitable punishment requires that the two different parts of the brain work in tandem to find a balance. In the study, the rTMS upset this balance and interfered with deciding punishments.

Previous research has suggested that the part of the brain reviewed in this study is used primarily in simple tasks. It also plays a role in memory and behavior. Researchers now believe that it is an important part of complex decision making.

This research has important implications for the increasing prevalence of neuroscience in the criminal justice system. Understanding how the brain makes decisions about guilt and punishment may eventually help the court system ensure that better decisions are made.


This research, in combination with other advances in brain science, like understanding criminal behavior, can help ensure that the appropriate punishments are delivered to relevant guilty parties.

A better understanding of how guilt and punishment are decided will be especially important in the field of juvenile crimes. Understanding how punishments are decided for juvenile crime will hopefully help create a fairer system of punishment for youth.

For example, recent research has suggested that youth are more likely to commit worse crimes when they are a part of a group. Younger brains respond more to rewards in groups than they do alone. However, current punishments for gang crimes are harsher than punishments for crimes committed alone. This is in direct opposition to scientific evidence.

Assessing blameworthiness and delegating punishment are distinct cognitive processes. Hence, understanding the effect of these processes on decision making is important. If the court system can recognize that the processes in decision making are as complex as the criminal brain itself, it can work to create systems to keep these processes in check.


Although it’s impossible to know for sure, some estimates suggest that between 2.3% and 5% of American prisoners are innocent of the crimes they were convicted of. Using neuroscience research to make sure better decisions are made can help keep innocent people out of jail.

Featured photo credit: David Ohmer via

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Science Says Silence Is Much More Important To Our Brains Than We Think

Science Says Silence Is Much More Important To Our Brains Than We Think

In 2011, the Finnish Tourist Board ran a campaign that used silence as a marketing ‘product’. They sought to entice people to visit Finland and experience the beauty of this silent land. They released a series of photographs of single figures in the nature and used the slogan “Silence, Please”. A tag line was added by Simon Anholt, an international country branding consultant, “No talking, but action.”

Eva Kiviranta the manager of the social media for said: “We decided, instead of saying that it’s really empty and really quiet and nobody is talking about anything here, let’s embrace it and make it a good thing”.

Finland may be on to something very big. You could be seeing the very beginnings of using silence as a selling point as silence may be becoming more and more attractive. As the world around becomes increasingly loud and cluttered you may find yourself seeking out the reprieve that silent places and silence have to offer. This may be a wise move as studies are showing that silence is much more important to your brains than you might think.

Regenerated brain cells may be just a matter of silence.


     A 2013 study on mice published in the journal Brain, Structure and Function used differed types of noise and silence and monitored the effect the sound and silence had on the brains of the mice.[1] The silence was intended to be the control in the study but what they found was surprising. The scientists discovered that when the mice were exposed to two hours of silence per day they developed new cells in the hippocampus. The hippocampus is a region of the brain associated with memory, emotion and learning.


    The growth of new cells in the brain does not necessarily translate to tangible health benefits. However, in this instance, researcher Imke Kirste says that the cells appeared to become functioning neurons.

    “We saw that silence is really helping the new generated cells to differentiate into neurons, and integrate into the system.”

    In this sense silence can quite literally grow your brain.

    The brain is actively internalizing and evaluating information during silence


      A 2001 study defined a “default mode” of brain function that showed that even when the brain was “resting” it was perpetually active internalizing and evaluating information.


      Follow-up research found that the default mode is also used during the process of self-reflection. In 2013, in Frontiers in Human Neuroscience, Joseph Moran et al. wrote, the brain’s default mode network “is observed most closely during the psychological task of reflecting on one’s personalities and characteristics (self-reflection), rather than during self-recognition, thinking of the self-concept, or thinking about self-esteem, for example.

      “When the brain rests it is able to integrate internal and external information into “a conscious workspace,” said Moran and colleagues.

      When you are not distracted by noise or goal-orientated tasks, there appears to be a quiet time that allows your conscious workspace to process things. During these periods of silence, your brain has the freedom it needs to discover its place in your internal and external world.

      The default mode helps you think about profound things in an imaginative way.

      As Herman Melville once wrote,[2]


      “All profound things and emotions of things are preceded and attended by silence.”

      Silence relieves stress and tension.


        It has been found that noise can have a pronounced physical effect on our brains resulting in elevated levels of stress hormones. The sound waves reach the brain as electrical signals via the ear. The body reacts to these signals even if it is sleeping. It is thought that the amygdalae (located in the temporal lobes of the brain) which is associated with memory formation and emotion is activated and this causes a release of stress hormones. If you live in a consistently noisy environment that you are likely to experience chronically elevated levels of stress hormones.

        A study that was published in 2002 in Psychological Science (Vol. 13, No. 9) examined the effects that the relocation of Munich’s airport had on children’s health and cognition. Gary W. Evans, a professor of human ecology at Cornell University notes that children who are exposed to noise develop a stress response that causes them to ignore the noise. What is of interest is that these children not only ignored harmful stimuli they also ignored stimuli that they should be paying attention to such as speech. 

        “This study is among the strongest, probably the most definitive proof that noise – even at levels that do not produce any hearing damage – causes stress and is harmful to humans,” Evans says.[3]

        Silence seems to have the opposite effect of the brain to noise. While noise may cause stress and tension silence releases tension in the brain and body. A study published in the journal Heart discovered that two minutes of silence can prove to be even more relaxing than listening to “relaxing” music. They based these findings of changes they noticed in blood pressure and blood circulation in the brain.[4]

        Silence replenishes our cognitive resources.


          The effect that noise pollution can have on cognitive task performance has been extensively studied. It has been found that noise harms task performance at work and school. It can also be the cause of decreased motivation and an increase in error making.  The cognitive functions most strongly affected by noise are reading attention, memory and problem solving.

          Studies have also concluded that children exposed to households or classrooms near airplane flight paths, railways or highways have lower reading scores and are slower in their development of cognitive and language skills.

          But it is not all bad news. It is possible for the brain to restore its finite cognitive resources. According to the attention restoration theory when you are in an environment with lower levels of sensory input the brain can ‘recover’ some of its cognitive abilities. In silence the brain is able to let down its sensory guard and restore some of what has been ‘lost’ through excess noise.[5]



          Traveling to Finland may just well be on your list of things to do. There you may find the silence you need to help your brain. Or, if Finland is a bit out of reach for now, you could simply take a quiet walk in a peaceful place in your neighborhood. This might prove to do you and your brain a world of good.

          Featured photo credit: Angelina Litvin via


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