Susanna Kaysen is an American author best known for her memoir, Girl, Interrupted, published in 1993. The book recounts her experiences in a psychiatric hospital during the 1960s and explores themes of mental illness, identity, and the societal perceptions of sanity. Kaysen's writing often reflects her own struggles with mental health, and she has contributed to discussions about the complexities of psychological disorders. In addition to Girl, Interrupted, she has written several other works, including novels and essays, which further delve into personal and societal issues.