Vision in a Monkey without Striate Cortex: A Case Study

A rhesus monkey, Helen, from whom the striate cortex was almost totally removed, was studied intensively over a period of 8 years. During this time she regained an effective, though limited, degree of visually guided behaviour. The evidence suggests that while Helen suffered a permanent loss of ‘focal vision’ she retained (initially unexpressed) the capacity for ‘ambient vision’.