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..................................................................................................................... xii LIST OF ABBREVIATIONS USED .............................................................................. xiii ACKNOWLEDGEMENTS ............................................................................................. xiv CHAPTER

Many behaviors require rapid and precisely timed synaptic transmission. These include the determination of a sound's direction by detecting small interaural time differences and visual processing, which relies on synchronous activation of large populations of neurons. In addition, throughout the brain, concerted firing is required by Hebbian learning mechanisms, and local circuits are recruited...

In this issue of Neuron, Sara et al. find that spontaneously released miniature synaptic potentials arise from a pool of vesicles distinct from those released by neural activity. This modification of a basic tenet of the quantal hypothesis has important implications for the analysis of changes in synaptic transmission.

Astrocytes, through their close associations with synapses, can monitor and alter synaptic function, thus actively controlling synaptic transmission in the adult brain. Besides their important role at adult synapses, in the last three decades a number of critical findings have highlighted the importance of astrocytes in the establishment of synaptic connectivity in the developing brain. In this...