Every day, we make thousands of decisions. Some are important, and some are not; some are impulsive and some are logical, some lead to gains, and some lead to losses.
Cost-benefit decisions have been frequently studied in psychology, yet little has been discovered about the neurological mechanisms which accompany these decision-making processes.
New research by scientists at the University of Georgia has been assessing how the brain behaves when people make a decision about drinking alcohol; specifically, they want to know what happens when the pros and cons are weighed against each other.
24 young men (21-31 years of age) who were heavy drinkers were recruited.
I need to put on my critical hat for a minute, and say that they should also have assessed the decision-making processes for moderate and light drinkers to see if there are differences; that’ll have some relevance to public health.
The researchers gave each man a $15 bar tab and put them in an MRI scanner. They then asked the participants to decide how they would spend their money on a variety of drinks. Any drinks they chose in the scanner were given to them after the study, and any money they didn’t spend was theirs to keep.
Participants’ cost-benefit decisions were categorized into those in which drinking was perceived to have all benefit and no cost (i.e. a cheap drink), to have both benefits and costs (i.e. a moderately priced drink), and to have all costs and no benefits (i.e. an expensive drink).
Critical hat again! They should have also measured the participants’ preferences for various drinks — I know myself that even if rum is significantly cheaper than all the other drinks, it will only have costs for me!
When participants decided to drink in general, activation was seen in several areas of the cerebral cortex, such as the prefrontal and parietal cortices. However, when the decision to drink was affected by the cost of alcohol, activation involved frontostriatal regions. These regions are important for the interplay between cognitive deliberation and subjective reward value.
When participants decided not to buy a drink, their brain activity was most differentially active which suggests the participants were experiencing the most conflict. The area of the brain known as the anterior insula was active during these conflict decisions.
“It was interesting that the insula was sensitive to escalating alcohol costs especially when the costs of drinking outweighed the benefits,” MacKillop said. “That means this could be the region of the brain at the intersection of how our rational and irrational systems work with one another.”
This research is important, because at the moment treatment for alcoholism is only moderately effective. If we are able to find more ways to identify at-risk people through their neurological patters when they made decisions about alcohol consumption, we can begin to develop treatments specifically for this population.
If anyone is interested in reading the paper, here is the link: http://www.nature.com/npp/journal/vaop/naam/pdf/npp201447a.pdf