Roman numerals in an outline signify main idea

the support that the author, uses in the article facing our fears is a): a definition of the part of the brain called the amygdala.

he takes neuroscientist joseph ledoux's words by telling that by falling to distinguish between evolutionary old systems located in the amygdala and newer systems, centered in the prefrontal cortex, doctors have conflated non conscious threat circuits in the brain with circuits that underlie the conscious experience of fear. that, the author says, "leads ledoux to the jarring conclusion that the amygdala, a decades-old centerpiece of the brain's fear circuit, does not underlie the conscious feeling of fear".

despite this, the author points out in the article that that is a controversial notion and that evidence, in animal and humans, supports the idea that core emotions can exist outside of conscious awareness.

  this riddles' answer is library.

  the "leaves" are a reference to the books' pages that the library contains; the branches are a network of libraries that connect multiple libraries' collections, resources, and items in a system of a common database, integrating them; the branches' organization are a useful management tool for coordinating the multiple collections many libraries have.