In this remarkable collection of essays, part of the American Lives series (edited by Tobias Wolff), Skloot (The Night Side) conveys what it is like to live with a damaged brain. In 1988, Skloot was beset by a virus that left him with brain lesions (static dementia) that dramatically affected his ability to think. (Because of this condition, each piece here took one to two years to complete and was constructed laboriously in small periods of time.) He often cannot find an appropriate word and may say, for example, "pass the sawdust" instead of "pass the rice." He forgets faces, names, directions and how to perform simple tasks, and suffers from loss of balance. Skloot, now in his late 50s, movingly describes how, despite his losses, he feels enriched by the life he shares with his very supportive wife, Beverly, in a quiet rural environment. Of particular interest is an account of a month that the couple spent on Ireland's Achill Island. Another section deals with his struggle to come to terms with a harsh childhood during which his mother, now in her 90s and sliding into dementia herself, routinely beat and abused him and his brother. The author also details, without self-pity, how he was subjected by the Social Security Administration to a series of tests to prove that his illness was organically based and his disability status legitimate. This is an unusual and engrossing memoir written with intelligence, honesty, perception and humor. (Mar.)