A team of researchers from Oxford University and University College London (UCL) has recently identified the parts of the brain involved in decision making, particularly when effort and reward are concerned. The higher the award, the more your brain pushes you to make an effort. The study was published in the Journal of Neuroscience.

The new study, supported by Wellcome Trust and European Research Council, was undertaken by Dr Miriam Klein-Flügge, PhD, and involved several volunteers who had to make choices involving different levels of monetary reward and physical effort.

Dr Miriam Klein-Flügge, PhD, Department of Experimental Psychology and the lead author of the study, says, “We found that the decisions they made were influenced by both reward size and effort required, with – unsurprisingly – higher reward, lower effort options being particularly favored. We then looked for particular brain regions involved in the decision making.

To find the exact pattern in decision making, the research team from Oxford and UCL participants were given a choice between different levels of efforts and monetary rewards. As the patients underwent MRI, the researchers studied the scans to locate the parts involved in decision making.

They found that three areas of the brain, the supplementary motor area (SMA), dorsal anterior cingulate cortex (dACC) and putamen were active during the decision making process.

As researchers dug further, they found SMS and putamen to be highly active during the “effort” part, indicating these are the brain centers associated with the effort and struggle. Another region of the brain called ventromedial prefrontal cortex seemed most active during the “assessment” part.

Dr Miriam says, “This research fits with and adds to findings from other studies. There is not one single decision making system in the brain but a set of them that are combined flexibly depending on the decision we are faced with. We have identified the system related to effort, a common factor in many decisions.”

She further adds, “It offers an insight for research into a number of disorders including depression, apathy and negative symptom schizophrenia. Patients with these disorders often show a reduced ability to do something effortful to obtain a reward.”

The scientists say that there are many situations which require us to contemplate whether the reward will be worth the effort. For example, like deciding to go an extra mile to get a delectable food item or exerting less effort for something normal.

Dr Raliza Stoyanova, in the Neuroscience and Mental Health team at Wellcome, said about the current study that it points out that although our brain reacts differently to rewards of different sizes and there are countless variables that affect our decision making power, this highlights the range of psychiatric conditions involved in unbalancing the effort and reward mechanism and this opens up avenues for future research to pinpoint the effort and reward mechanism.

Brain’s Decision Making System

The human brain contains 100 billion neurons and many more glial cells, which supply the neurons with nutrition. Each neuron is connected with at least 10,000 other neurons. In terms of processing speed, some scientists estimate that the human brain computes at 1 trillion bits per second while the frontal lobe of the cerebral cortex is involved in decision making.

The brain is the least understood part of the human body and the mind even less. When it comes to decision making, it initiates a seamless process in the brain which we are unaware of until we face the consequences. Good or bad consequences of effort conditions responses during future decision making.

Scientists believe that reasoning develops from rapid and complex calculations in our brain and it appears to be programmed to enable us to make the best decisions possible by analyzing sensory evidence and past experiences in its sensory circuits.

The brain’s decision making power comes a long way by surviving teenage years. A study found out that adults have greater activity in the frontal lobes and lower activity in the amygdala than teenagers. As the frontal lobe is responsible to control impulses and instant gratifications, it showed that adults have a greater control to delay emotions and desires at inappropriate instances.

Furthermore, what the scientists found was that the amygdala is the cause of instinctive decisions and “fight or flight” responses and therefore a hyperactive amygdala causes teens to take part in risky behaviors.

By studying stroke patients researchers found that people with damage to the front side of the brain have trouble making abstract decisions while people with damage in the back side have trouble making concrete decisions.

Additionally, it was found out by scientists that cocaine addicts have trouble deciding if the “high” of cocaine was worth the health problems associated with drug use because of neural degradation in the orbitofrontal cortex of brain.