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The amygdala: fears, actions, and bigotry
Th Wisconsin county where I grew up had basically zero black people living there until 1990. Rumor had it that shortly after the first black family moved into my hometown, someone threw rocks through their windows. Actions can cement our biases, for better or for worse. Dramatic actions based on bigotry, say fear of a changing demographic, will literally change the brain. Neural networks grow more dedicated to a racist ideology when fearleads to action. Fear centers on the amygdala, which has anatomical connections to the cortex, which in turn influences behaviors. recent discoveries include the idea that the neurotransmitter noradrenaline impacts the oscillations of neurons in the amygdala, transitioning the brain to a state of heightened arousal, leading to a conditioned expression of fear. Better understanding the neuroanatomy of our behavior opens up the possibility of targeted therapies. We can repair a broken window, and we can repair fear-based bigoty as well.
The shooting of Philando Castile - the amygdala's role in biased fear behavior
What I describe as the bias center includes the amygdala, often described as our fear locus. But in reality, the amygdala has many roles and only in certain circumstances activates to enhance fear based behaviors. this was particularly on display in the traffic stop that ended with Jeronimo Yanez shooting Philando Castille to death. Warning - we are about to watch a violent clip – pay attention to Yanez’s three increasingly panicked statements betraying his subjective and incorrect view that Castile was a threat. The panic continued after, demonstrated by his hysterical shouting. My opinion: (1) Yanez’s amygdala was almost completely in charge and demonstrating a conditioned expression of fear, and (2) because Castile was Black, Yanzs amysala activity incas even more, leading to violent behavior. It’s controversial, so I want to expose the science behind it. Let’s explore the amygdala for a bit.
Unconscious bias-amygdala activation in the brains of white people when flashed a Black face
Outgroup bias can occur at a subconscious level, even for folks who are consciously not prejudiced. In this study, 13 white participants allowed real time reading of their brain activity through fMRI. Importantly they each reported internalized desire to respond without prejudice. When presented a picture of a face for 30 msec, a time course during which most individuals aren’t consciously aware they were shown a face, there was more amygdala activity when shown a Black face than when shown a white face. The amygdala has different roles, but is known as the brain’s fear center. So, especially when we pair this study with the change in the oscillations of the amygdala under conditions of stress, the amygdala may be at the center of, or at least takes part in, unconscious bias and fear based behavior which sometimes leads to violence. With a longer time course of 565 msec, when there was a conscious understanding of a face and its color, the Black-White difference was significantly reduced – presumably automatic attitudes were counteracted by more positive controlled attitudes. This correlated with more activity in the prefrontal cortex and the executive function portions of the brain.