She is a biological (also called biopsychological) psychologist.

Explanation

  • In psychology, the specialty that studies how the structure and function of the nervous system relates to behavior is called biological psychology or biopsychology.
  • Biopsychologists focus on how the brain, neurons, and other biological systems influence thoughts, emotions, and actions.

So, the sentence should read:

“Penelope studies how the structure and function of the nervous system is related to behavior. She is a biological psychologist (or biopsychologist).”

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