Understanding Your Brain In Order to Make Better Decisions.

As you begin to read this article, your brain is making an instantaneous decision: should you continue to read? Your brain’s ability to analyze a situation and draw conclusions about what is best would not be possible without one region of the brain in particular.

The amygdala, a part of the brain located alongside the frontal cortex, evaluates the benefits and risks of a decision in fractions of a second, communicating with the rest of the brain to avoid potential threats. When your brain encounters new stimuli, such as this article, the amygdala is the first to respond, generating what feels like a gut reaction to a scenario.

There is an internal library of fears, finely tuned to avoid situations that result in loss, located within your amygdala. When you see snakes, spiders, and sharks a sense of fear surges through your body, manifesting itself as changes in body temperature, heart rate, and muscle tension. Being aware of when and how the amygdala influences your decision-making might be the difference between life and death.

Fear Perception

That moment of panic, when you feel frozen in terror, is a result of the amygdala’s evolutionary survival kit. Arne Ohman, a professor at the Karolinska Institutet Emotion Lab, produced a 2001 study first delving into the impact of instinctual emotions on speed of thought.

A Matrix

When faced with a matrix of nine images, similar to the one above, subjects were asked to locate the picture that did not belong. Ohman discovered that when one spider or snake was located in an array of flowers or mushrooms, the reaction time needed to locate the different image was significantly less than when faced with 8 spiders or snakes. The results of the study indicated that humans have predisposed fears that influence the way we react to dangerous stimuli. There were improvements in reaction time when faced with a single danger but slower reactions when faced with multiple threats (Ohman, 2001).

Snakebites are one example of a threat addressed in Ohman’s research, but the statistics behind snakebites don’t quite add up. Many people fear snakes, but only approximately 1 in 40,000 people are bitten by snakes in the United States, indicating the risk of a snake bite is actually quite small. So the next time you see a snake, make a conscious effort to recognize the effects of the amygdala on your reactions to fear-inducing stimuli and then the snake seems less frightening.

What might be even more frightening is losing money.

Loss Perception

If someone asked you to bet on the flip of a fair coin, gaining $25 if it’s heads but losing $20 if it’s tails, would you take the bet? For many, the thought of losing $20 is not worth the risk; however, if this bet was repeated again and again (assuming its Friday and you just got paid) after a while you would make a profit. As you might have gathered, the amygdala not only affects risk perception, but also the ways we as humans perceive loss, making us react irrationally when faced with loss.


There is a way to quantify the effects of the amygdala on loss perception utilizing the Iowa Gambling Test (IGT). One study done at the University of Iowa questions a person’s willingness to bet when given varying monetary incentives, disincentives, and odds via the IGT(Gupta et al., 2011). The test was given to one group of subjects who all possessed a fully functional amygdala and ventromedial prefrontal cortex (VMPC), which is a region of the brain closely associated with the activity in the amygdala. In order to compare the amygdala’s effects on the result, the other group of subjects had either a damaged VMPC or a damaged amygdala. Healthy participants were able to better judge when to bet and when to be risk-averse, but tended to reject situations when the odds were in their favor.

The triggering of emotions when making decisions combined with the repetition of the same event leads to a similar reaction as the people learn what works best. Additionally, by also including subjects with injured VMPCs, the experiment presented new information about the connections between the memory of previous gambles and the VMPC. However, the memory of previous results encourages loss-averse tendencies that may not be entirely rational.

An Aside- Other Parts of the Brain Involved in Emotional Decision Making

It rare to see a single piece of the human body working in a vacuum, and this is also true when it comes to making decisions. There are instantaneous communications between the orbitofrontal cortex (OFC), a part of the brain responsible for helping to process new stimuli, and the amygdala that further influence our subconscious thoughts about a decision.


The issue with a lot of the research done in the field of behavioral neuroscience is that many researchers focus exclusively on one part of the brain and it’s role in decision-making. Some scientists like Rick Jenison, a psychologist at the University of Madison, are trying to change this. Jenison performed a study specially designed to look at whether the amygdala communicates with the OFC directly as well as looking for communication in the opposite direction. Initially, the OFC sends signals to the amygdala about the stimuli, which then replies with a significantly greater number of signals back to the OFC. The amygdala may play a huge role in processing information, but requires help to do its job. Understanding the connections between the different parts of our brain can help us make more calculated decisions.

Using The Information

As the decisions results accumulate within the brain, habits develop as a result of the outcomes of the choices you make. Emotions are felt as a result of your amygdala’s reaction to a situation. Ben Seymour, a Principal Investigator at Cambridge University, described this process as a Pavlovian learning system, a reference to the famous physiologist who first formulated theories about classical conditioning using dogs and a bell.

Pavlov's Experiment

Seymour hypothesized that the emotions generated by your amygdala when faced with a difficult decision actually improve human decision making capabilities. The ability to instantly recall the emotions felt after previous similar decisions gives humans a huge advantage in maximizing personal benefits. (Seymour, 2008).

Human emotion often serves as a message to the brain about what the body wants or needs; the ability to recall these feelings and react based on them serves as another way the amygdala influences behavior and encourages “safe” behavior.

Your brain is constantly reacting to new information in fractions of a second, in many cases helping you to protect yourself and follow your initial instincts. However, it is important to recognize these reactionary mechanisms as exactly that, and always think through the response to any situation, whether it be to fold after a poor flop, or to turn and run when faced with a snake ready to spring toward you.


Gupta, R., Koscik, T., Bechara, A., Tranel, D. (2011) The Amygdala and Decision-making. Neuropsychologia. 49 (4), 760-766

Jenison, R. (2014) Directional Influence between the Human Amygdala and Orbitofrontal Cortex at the Time of Decision-Making. PLOS One. 9 (10), e109689

Ohman, A., Flykt, A., Esteves, F. (2001) Emotion Drives Attention: Detecting the Snake in the Grass. Journal of Experimental Psychology: General, 130 (3) 466-478

Seymour, B., Dolan, R. (2008) Emotion, Decision Making, and the Amygdala. Neuron, 58 (5), 662-671. http://www.sciencedirect.com/science/article/pii/S0896627308004558