The evolution of the brain has depended on the allowance of strategies that pertain to, well, survival. In Chapter 2 we read about the amygdala helping to remember things like environmental threats or stimuli that produce a fear response. This can be plenty helpful when learning that lions and other big cats are not sleeping in the early mornings and later in the evenings. The unconscious shiver produced on a beautiful morning in a lush orchard may just turn out be lifesaving if it prompted the right memory back in the year 10,000 BCE.
Part 1
1. What if cells in the amygdala never developed an ability to change with experience? In other words, what if they could not undergo any biological processes associated with learning?
2. How would not having an ability to predict a possible threat affect human behaviors today?
3. Conversely, consider what it might be like to have a really enhanced, out-of-this world, phenomenal, super-sensitive capability to learn everything and anything that might be considered a threat?
This would leave us incredibly vulnerable to repeated dangers, as we'd lack the ability to adapt our behavior to avoid threats we've already encountered. Survival would be a matter of pure chance, not learned strategy.
2. How would not having the ability to predict a possible threat affect human behaviors today?
Without the ability to predict threats, human behavior would be characterized by a significant lack of caution and risk assessment. Today, we rely on this subconscious learning to navigate our daily lives safely. For example, we automatically flinch or jump back from a loud, unexpected noise, a reflex developed from our amygdala's association of such sounds with potential danger. We know to look both ways before crossing a street, a behavior learned from countless observations of traffic. Without this predictive capability, we would likely engage in highly risky behaviors without a sense of impending danger. This would lead to a dramatic increase in accidental deaths and injuries from preventable events, as our bodies would not produce the physiological responses (e.g., increased heart rate, adrenaline release) that prepare us for a "fight or flight" response. Our social interactions might also be affected, as we would not instinctively learn to avoid people or situations that have proven to be harmful in the past.
3. What if we had a super-sensitive capability to learn everything and anything that might be considered a threat?
A super-sensitive capability to learn and remember threats would lead to a state of hyper-vigilance and extreme anxiety. While this might seem advantageous for survival, it would likely be debilitating. We would learn to fear not just real threats (like a venomous spider) but also anything remotely associated with them. A person might develop an intense fear of all insects, or even the sound of rustling leaves, after a single negative experience. . This enhanced learning would result in an overactive amygdala, constantly producing fear responses to benign stimuli. Everyday life would be a series of panic attacks and avoidance behaviors, as almost every new experience could be linked to a potential threat, no matter how remote. This condition is similar to what is seen in people with severe anxiety disorders or Post-Traumatic Stress Disorder (PTSD), where the brain's threat-detection system is in a constant state of high alert, making it difficult to function normally.
Sample Answer
The Amygdala and Its Role in Learning and Survival
The amygdala's ability to undergo biological processes associated with learning is fundamental to survival. This process, known as synaptic plasticity, allows the brain to change and adapt in response to experience.
1. What if cells in the amygdala never developed the ability to change?
If the cells in the amygdala were static and could not undergo any biological processes associated with learning, we would be unable to form or retrieve fear-based memories. This would mean that an individual who experienced a traumatic or dangerous event—such as being attacked by a snake or bitten by a dog—would not learn to associate that specific animal or situation with a threat. Every new encounter with a similar stimulus would be treated as an unfamiliar event, without any learned fear response.