The amygdala (emotion centre) of the autistic brain has been shown to be easier to trigger, as well as harder to shut off, than those in the brains of neurotypicals. What this means is that when something sparks an emotion, it escalates more quickly than NT emotions do, and can be very hard to shut off at the appropriate time, not unlike a train with its brakes cut; once it starts moving, there's no stopping it. What this means is that when we get excited by something, that excitement builds and becomes very intense, far more intense than it would if NTs were in the same situation, because their emotion is slower to trigger, as well as slower to build, and quicker to extinguish once the stimulus triggering the emotion has disappeared. This unique functioning of the amygdala is also what causes meltdowns in autistics; our emotions escalate and get out of control because once they start, it's hard to think rationally to slow them down and bring them back to normal, so they get worse and worse until everything explodes.
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"Survival is insufficient" - Seven of Nine
Diagnosed with ASD level 1 on the 10th of April, 2014
Rediagnosed with ASD level 2 on the 4th of May, 2019
Thanks to Olympiadis for my fantastic avatar!