Brain research is moving forward in leaps and bounds over the last few years. This gives scientists an increasingly comprehensive insight into the inner workings of the brain. The more results and conclusions are published, the better they can map out the brain and suggest additional research into specific areas.
Veit Stuphorn researched risky decisions
Velt Stuphorn is one of those specialized researchers, having focused the last twenty years into a small area in the brain called SEF: Supplementary Eye Field. This brain area was discovered in 1874 by Scottish neurologist David Ferrier. He indicated it being a reasonably large area. After substantive research, it appears much smaller than Ferrier thought, but no less important.
The SEF manages our eye movements, such as saccades: the quick and simultaneous eye movements that help you fixate on a different focal point, such as in reading words (your eyes subconsciously jump (saccades) from one section of a word to the next). Those saccades are, together with blinking, the fastest movements in the human body.
In recently conducted research into the SEF, Veit Stuphorn and Xiaomo Chen discovered that it plays an important part in risky decisions. This research is especially interesting because it can help give more insight into treating gambling addictions.
Previous insights into gambling addictions showed that compulsive behaviors can’t just be explained by looking at the reward center in the brain – the ‘pleasure’ part that creates dopamine after a pleasant stimulus.
A rhesus monkey (photo: JM Garg)
These researchers at John Hopkins University used two rhesus macaques named Aragorn and Isildur. Rhesus macaques are monkeys with a similar brain structure and setup as humans.
Stuphorn and Chen taught the monkeys to gamble using two different ways to get water. By playing on a computer, Aragorn and Isildur had to pick between a 20% chance at 10 ml waters and an 80% chance to get 3 ml. The monkeys kept trying for the 10 ml, even after their thirst was quenched.
Stuphorn’s hypothesis, based on earlier research, was that the SEF would play a role in the decision making process. As a next step in the research, he and his colleague used two microelectrodes that cooled down the SEF area, a procedure that would numb it and cause less activity.
However, they observed that these microelectrodes hardly affected the SEF. The eye movements, fixation, reaction time, and other similar factors hardly changed. Nevertheless, the effect on the risky decisions was significant. The choice for a 20% chance for 10ml water decreased by roughly 35% in both monkeys.
This surprised Stuphorn, even though it confirmed his hypothesis. He knew the SEF and surrounding areas played a role in decision making. The big effects of isolating the area were still an intriguing surprise to him.
It’s remarkable that a specific area of the brain can have these significant effects on processing a risk. The researchers believe they have demonstrated that the SEF is a key cognitive area – the area in the brain that allows us to gain and process knowledge.
The SEF helps estimate the environment around us. This estimate is then used by other areas of the brain to determine risks and dangers. Much of the decision-making process in the brain is still an unknown territory, though.
Research, such as these experiments by Xiaomo Chen and Veit Stuphorn, help scientists understand which factors influence risky decisions. This in turn can be insightful in developing gambling addiction treatments.
Such treatments could consist of Deep Brain Stimulation (DBS), a technique already in use with Parkinson patients or people suffering from OCD.
A surgeon places small electrodes in specific areas of the brain. These electrodes send electromagnetic pulses that can interfere with problematic signals in the brain. This direct interference eliminates a lot of the negative side effects that are common in the regular treatment with medication.
As mentioned above, gambling addictions aren’t just explained by looking at the brain’s reward center. The addition of, for example, the SEF helps explain the relationship between the two areas in the inner workings of an addiction.
It’s interesting to see how the SEF works with rewards, if and how it interacts with the release of dopamine, or whether risky decisions are made entirely independent of the brain’s reward center. All these questions are still open for future research, so in the foreseeable future you’ll be playing online blackjack without the electrodes.
Veit Stuphorn and Xiaomo Chen published their findings in the scientific journal Current Biology. You can find a PDF version here.
9 oktober 2018
