Samuel Beckett and Jorge Luis Borges have presented 20th century literature with a distinctive gallery of solitary figures who suffer from a series of physiological ailments: invalidism, decrepitude, infirmity and blindness, as well as neurological conditions such as amnesia and autism spectrum disorders. Beckett and Borges were concerned with the dynamics between illness and creativity, the literary representation of physical and mental disabilities, the processes of remembering and forgetting, and the inevitability of death. This article explores the depiction of physically and mentally disabled characters in Borges' Funes the Memorious (1942)--a story about an Uruguayan gaucho who has been left paralysed after a fall from a horse which simultaneously endowed him with an infallible memory and perception--and Beckett's Trilogy: Molloy (1951), Malone Dies (1951) and The Unnamable (1953). It examines the prodigious memory of Funes and the forgetful minds of Molloy and Malone with reference to influential neuropsychological studies such as Alexander Luria's twofold exploration of memory and forgetfulness in The Mind of a Mnemonist (1968) and The Man with a Shattered World (1972). The article demonstrates that in contrast to Beckett's amnesiacs and Luria's brain-damaged patient, who are able to transcend their circumstances through cathartic writing, Borges' and Luria's mnemonic prodigies fail to achieve anything significant with their unlimited memories and remain imprisoned within their cognitive disabilities. It reveals that medical discourses can provide invaluable insights and lead to a deeper understanding of the minds and bodily afflictions of literary characters.