Keep in mind that the researcher was only 23 years old at the time when the lab accident happened. In some ways, she was basically a kid. As everyone knows, she ended up dying because of this.
A human has a fully developed adult brain around age 25, but for some people it is not until age 30 [1].
[1] https://bigthink.com/mind-brain/adult-brain?rebelltitem=1#re...