This book provides overviews of two broad areas of memory research. The papers in the first section are concerned with experimental and clinical studies of different neurochemical systems mediating memory and cognition. In the second section, there are reviews of studies of various "abnormalities" of memory functioning, including chapters on memory dysfunction in patients with dementia and those with organic amnesia, on memory bias in patients with mood disorders and on the characteristics and explanations of exceptional memory performance. Thus, the two sections of the book provide examples of contrasting, yet equally valuable strategies for understanding the nature of memory. These reviews of the work on the neurochemistry of memory, on dysfunction and individual differences provide a range of insights into the structure and function of memory mechanisms and enable the reader to understand the reciprocal relation of this work to current psychological approaches and models.