Carolina Maria de Jess was a fiercely proud black Brazilian woman who lived in a So Paulo favela with her three illegitimate children (each with a different father). She had learned to read and write by continuing to study on her own after only two years of primary school. In 1958 fragments of her diary came to the attention of an enterprising journalist, Audlio Dantas, who helped her get it published. For a brief period, Carolina Maria de Jess became an international celebrity as the author of the best-selling book in Brazilian publishing history. For many reasons, however, Carolina fell from favor: the rise of a military dictatorship in 1964, which led to an accompanying reaction against social criticism, and especially the ways in which she handled her fame and related to the press and the literary elite. Within a few years, she was forced to move back into the favela and scavenge for a living. A brief flurry of publicity in 1969 about her fallen condition prompted a slight improvement in her circumstances, but she was soon forgotten again. Carolina died in 1977, on the verge of indigence. Her complete life story has never been told, and most Brazilians today are unaware that a black favelada in the 1960s became the symbol (to foreigners, at least) of the struggle to rise above poverty. Most Brazilians neither read her books nor consider them noteworthy. Evidently, the author of what The New York Times called a rarely matched essay on the meaning and the feeling of hunger, degradation, and want touched no nerve in the Brazilian sensibility.

Background: Eye movements reveal neurodegenerative disease processes due to overlap between oculomotor circuitry and disease-affected areas. Characterizing oculomotor behaviour in context of cognitive function may enhance disease diagnosis and monitoring. We therefore aimed to quantify cognitive impairment in neurodegenerative disease using saccade behaviour and neuropsychology. Methods: The Ontario Neurodegenerative Disease Research Initiative recruited individuals with neurodegenerative disease: one of Alzheimer’s disease, mild cognitive impairment, amyotrophic lateral sclerosis, frontotemporal dementia, Parkinson’s disease, or cerebrovascular disease. Patients (n=450, age 40-87) and healthy controls (n=149, age 42-87) completed a randomly interleaved pro- and anti-saccade task (IPAST) while their eyes were tracked. We explored the relationships of saccade parameters (e.g. task errors, reaction times) to one another and to cognitive domain-specific neuropsychological test scores (e.g. executive function, memory). Results: Task performance worsened with cognitive impairment across multiple diseases. Subsets of saccade parameters were interrelated and also differentially related to neuropsychology-based cognitive domain scores (e.g. antisaccade errors and reaction time associated with executive function). Conclusions: IPAST detects global cognitive impairment across neurodegenerative diseases. Subsets of parameters associate with one another, suggesting disparate underlying circuitry, and with different cognitive domains. This may have implications for use of IPAST as a cognitive screening tool in neurodegenerative disease.