09 Feb Are our choices even our own? Or are they rooted in our anatomy?
By Ava Lennon
As your body grows, so does your brain. Its different lobes develop throughout your adolescent years, so that by the time you’re an adult you can think and function correctly. The human brain reaches its complete adult volume at age 10, around a decade before it stops developing. The prefrontal cortex of the brain, which sits behind the forehead, is the last part of the brain to finish maturing (early 20s). Best known for regulating impulses and emotions, the underdeveloped prefrontal cortex of teenagers is often blamed for their reckless decisions and poor judgment.
Since the teenage brain isn’t fully developed to understand consequences and regulate impulses, it has to rely on a different part of the brain—the amygdala—to understand decisions. The amygdala, a collection of structured cells in the middle of the brain, is associated with emotional processes: specifically with the response known as ‘fight or flight’. Without the logical reasoning of the prefrontal cortex, the use of the amygdala in decision-making can lead teenagers to make emotional and impractical decisions without thinking through the consequences.
Another aspect of decision-making non-specific to the growing adolescent brain has to do with the formation of neural pathways in the brain that link together ideas, known as heuristics. Three main heuristics, or shortcuts, play a role in our risk assessment and decision making: availability heuristic, representativeness heuristic, anchoring heuristic, and adjustment heuristic. Availability heuristic impacts how somebody understands the situation by recalling past experiences that relate to it. Representativeness heuristic draws conclusions from reinforced stereotypes rather than focusing on statistics and likelihood of occurrence. Anchoring heuristic is the tendency to rely on the first piece of information learned on a subject. Adjustment heuristic is when the initial information on a subject is adjusted as new information is received, but more often than not, remains close to the anchoring heuristic.