Analogue pattern matching in a dendritic spine model based on phosphorylation of potassium channels

Modification of potassium channels by protein phosphorylation has been show n to play a role in learning and memory. If such memory storage machinery w ere part of dendritic spines, then a set of spines could act as an 'analogu e pattern matching' device by learning a repeatedly presented pattern of sy naptic activation. In this study, the plausibility of such analogue pattern matching is investigated in a detailed circuit model of a set of spines at tached to a dendritic branch. Each spine head contains an AMPA synaptic cha nnel in parallel with a calcium-dependent potassium channel whose sensitivi ty depends on its phosphorylation state. Repeated presentation of synaptic activity results in calcium activation of protein kinases and subsequent ch annel phosphorylation. Simulations demonstrate that signal strength is grea test when the synaptic input pattern is equal to the previously learned pat tern, and smaller when components of the synaptic input pattern are either smaller or larger than corresponding components of the previously learned p attern. Therefore, our results indicate that dendritic spines may act as an analogue pattern matching device, and suggest that modulation of potassium channels by protein kinases may mediate neuronal pattern recognition.