Book excerpt: Brain damage can cause memory to break down in a number of different ways, the analysis of which can illuminate how the intact brain mediates memory processes. After first considering the problems involved in assessing memory, this book provisionally advances a taxonomy of elementary memory disorders and, for each in turn, reviews both the specific processes that are disrupted and the lesions responsible for the disruption. These disorders include short-term memory deficits, deficits in previously well-established memory, memory decifits caused by frontal lobe lesions, the organic amnesias, the disorders of conditioning and skill acquisition. Particular attention is paid to the organic amnesias, about which we know the most, and to the contributions of animal models to our knowledge. Andrew Mayes argues that the memory deficits found in several neurological and psychiatric syndromes comprise co-occurring elementary memory disorders. Finally, he outlines the implications of his taxonomy for our understanding of normal memory. A wide audience of researchers and students will find Human Organic Memory Disorders a helpful guide to a complex problem area.