Mrs. Agos is unable to recognize her husband by sight when he enters her hospital room. However, once she hears his voice, she recognizes him. Mrs. Agos has likely suffered damage to her

Mrs. Agos has likely suffered damage to her visual memory.

Explanation:

Mrs Agos has lost the sense of visual memory in the sense that she no longer recognizes the sights that she was used to see in her life and has not been able to recall even her husband from sight when she sees him right in front of her.

She is able to recognize him from his voice which means her auditory memory is fine and also that she does remember her husband which means that the memory itself is intact but the memory from the visual sense has been lost for her.