No Simple Brake - the Complex Functions of Inhibitory Synapses

Synaptic inhibition can be viewed as a counterbalance of synaptic excitation. However, mul-tiple recent studies at the cellular and network level show that inhibition serves a variety of additional, highly specific functions in the mammalian nervous system. At the molecular and cellular level, inhibitory synapses express diverse postsynaptic reversal potentials, kinetics, plasticity, and pharmacological modulation. This heterogeneity corresponds to the complexity of inhibition at the network level, where interneurons are now perceived as diverse and highly specific organizers of coherent activity patterns. We review some important new developments in the molecular, cellular and network physiology of inhibition. It turns out that understanding inhibition is a key to understanding neuronal network behaviour and, ultimately, may provide important clues for the development of novel therapeutic strategies in neuro-psychiatric diseases.