A model study of cellular short-term memory produced by slowly inactivating potassium conductances

We analyzed the cellular short-term memory effects induced by a slowly inac tivating potassium (Ks) conductance using a biophysical model of a neuron. We first described latency-to-first-spike and temporal changes in firing fr equency as a function of parameters of the model, injected current and prio r history of the neuron (deinactivation level) under current clamp. This pr ovided a complete set of properties describing the Ks conductance in a neur on. We then showed that the action of the Ks conductance is not generally a ppropriate for controlling latency-to-first-spike under random synaptic sti mulation. However, reliable latencies were found when neuronal population c omputation was used. Ks inactivation was found to control the rate of conve rgence to steady-state discharge behavior and to allow frequency to increas e at variable rates in sets of synaptically connected neurons. These result s suggest that inactivation of the Ks conductance can have a reliable influ ence on the behavior of neuronal populations under real physiological condi tions.