Chitra has suffered a head injury in a car accident. However, because she is such a dedicated teacher, she returns to teach her psychology class just a few days later. When she gets up in front of the class to lecture on hormones, she says, "Hormones . . . substances . . . pituitary . . . secreting . . . growth . . . ," and her students look at her blankly. Chitra has probably suffered damage to which part of the brain?