Even without medication, she appears to be very intelligent. When Mayor Quimby is recalled, she runs for the mayor's office. During a candidate debate, she is asked what public-policy issues are important to her. Unlike the other candidates (who act as stereotypical dishonest politicians), Abernathy discusses issues such as health care, economy, and public education in between her screams and gibberish (and a call for cats "in everyone's pants").
The Cat Lady enjoys "brief moments of lucidity" after taking psychoactive medication. She abruptly resumes her usual bizarre behavior when Marge mentions that the "pills" are actually Reese's Pieces. Her medication helps her speak intelligibly rather than her usual gibberish.