Cognitive function involves the participation of many different neurotransmitter systems in a variety of brain areas. The centerpiece of investigation regarding cognitive function has classically been the cholinergic system, but it has become increasingly clear that other transmitter systems interact with cholinergic systems to provide the neural systems for cognitive function. This book brings together cutting edge research to determine how the transmitter interactions form the mechanistic bases for attention, learning and memory. This research on transmitter interactions not only provides a more accurate, though complex, picture of how the brain works to provide cognitive function, it also provides important new levels of understanding about the mechanisms of cognitive dysfunction and novel avenues for therapeutic treatment. The researchers who contributed to this volume both reviewed their latest findings but also point to the directions of advancement of the field of neurotransmitter interactions and cognitive function.