This paper, presented at a colloquium on memory, explores neural mechanisms for visual memory and their role in attention. Robert Desimone discusses how visual memory in the inferior temporal (IT) cortex of monkeys is modulated by learning and memory processes. Three key effects are identified: repetition suppression, enhancement, and delay activity. Repetition suppression reduces neuronal responses to repeated stimuli, while enhancement increases responses to stimuli with learned relevance. Delay activity is crucial for maintaining information during short delays. These mechanisms influence competitive interactions between stimulus representations in the cortex, determining which stimulus is attended. Attention is closely linked to memory, as both processes are intertwined. Visual memory mechanisms in the IT cortex, such as repetition suppression and delay activity, impact attentional selection. However, enhancement and delay activity may depend on feedback from the prefrontal cortex, which is important for working memory. The study also examines the role of prefrontal cortex in visual memory, showing that it provides feedback to the IT cortex, biasing responses to stimuli relevant to memory. Prefrontal cortex cells exhibit stimulus-specific delay activity and match-enhancement, which may contribute to visual search tasks. The paper highlights that memory mechanisms, including repetition suppression and delay activity, are essential for attentional selection and visual search. These mechanisms are not only important for traditional memory tasks but also for attentional processes. The findings suggest that memory and attention are closely related, with memory mechanisms influencing cortical sensory processing and competitive interactions.This paper, presented at a colloquium on memory, explores neural mechanisms for visual memory and their role in attention. Robert Desimone discusses how visual memory in the inferior temporal (IT) cortex of monkeys is modulated by learning and memory processes. Three key effects are identified: repetition suppression, enhancement, and delay activity. Repetition suppression reduces neuronal responses to repeated stimuli, while enhancement increases responses to stimuli with learned relevance. Delay activity is crucial for maintaining information during short delays. These mechanisms influence competitive interactions between stimulus representations in the cortex, determining which stimulus is attended. Attention is closely linked to memory, as both processes are intertwined. Visual memory mechanisms in the IT cortex, such as repetition suppression and delay activity, impact attentional selection. However, enhancement and delay activity may depend on feedback from the prefrontal cortex, which is important for working memory. The study also examines the role of prefrontal cortex in visual memory, showing that it provides feedback to the IT cortex, biasing responses to stimuli relevant to memory. Prefrontal cortex cells exhibit stimulus-specific delay activity and match-enhancement, which may contribute to visual search tasks. The paper highlights that memory mechanisms, including repetition suppression and delay activity, are essential for attentional selection and visual search. These mechanisms are not only important for traditional memory tasks but also for attentional processes. The findings suggest that memory and attention are closely related, with memory mechanisms influencing cortical sensory processing and competitive interactions.