Locus Coeruleus in time with the making of memories.

Over the past decades studies of the neurobiology of memory were largely restricted to consideration of cellular and molecular events taking place immediately or shortly after training, the so-called consolidation period. More recent views have recognized that the memory process includes sensory processing, orienting of attention, retrieval, encoding, and subsequent consolidation. Advances in biotechnology are providing new tools to gain insights at every level of the memory process. New data from experiments employing high definition fMRI are confirming the role of the Locus Coeruleus (LC) noradrenergic system in reorienting of attention and in cognitive flexibility. Electrophysiological studies show new task-related activation of these neurons and learning-related off line activation and suggest a temporal relationship between LC spiking and cortical oscillations in the theta and gamma frequencies.