This research involves creating, exploring and testing mathematical models of dendritic neurons that are relevant to experimental neurophysiology and neuroanatomy. Together these models provide a theory that can account for various sequences of events in the soma and dendritic branches of a single neuron, and for field potentials generated by certain cortical populations of neurons. Computational experiments performed with these models provide theoretical predictions that have been compared with experimental results obtained by colleagues with motoneurons of cat spinal cord, and with the mitral cell and granule cell populations of rabit olfactory bulb. Resulting interpretations contribute to understanding of dendritic synaptic input and of dendro-dentritic synaptic interactions. Some of these results are summarized in Chapter 3 of """"""""The Handbook of Physiology: The Nervous System, Vol. 1"""""""", American Phyiological Soc. (1977) and in a Chapter entitled """"""""Functional Aspects of Neuronal Geometry"""""""" in """"""""Neurones Without Impluses"""""""", SEB Seminar Series, Cambridge Univ. Press (1981). When an intracellular microelectrode and an electronic control circuit are used to voltage clamp a neuron soma, and then a synapse is activitated at a dentritic branch location, it is important to distinguish the current generated at the synapse from the current that is detected experimentally at the soma by the clamping circuit. The mathematical relation between these currents has been presented and discussed in a Chapter (with I. Segev) include in the American Physiological Society monograph entitled """"""""Voltage and Patch Clamping with Microelectrodes"""""""" (1985). Our most recent computations have to do with dendritic spines. We have explored several interesting consequences of assuming excitable membrane properties at the heads of some dentritic spines.