Computing with oscillations by phase encoding and decoding

Even though brain oscillations are found in many brain regions, the role of oscillations in neural computation remains an open question. Experimental work in the hippocampus has provided examples where the phase of firing of neurons with respect to ongoing network oscillations codes for information. This scheme has been termed phase coding. A network receiving the phase encoded firing patterns must receive the oscillatory signal as well in order to utilize the phase code. Thus, the oscillatory coupling between brain networks often observed experimentally might reflect exchange of phase coded information. In this work, phase encoding and decoding that allow for a set of simple computations are demonstrated. These computations include simple list manipulations such as forward and backward sequence read-out as well as controlling the information flow between several networks. The mechanisms can be implemented in simple network models of integrate-and-fire neurons. The principle of phase coding provides an alternative to theories and models on neuronal computations based on rate coding.