Investigation of Factors Affecting Motif-Based Short- and Long-Term Memory Behaviour in Biological Networks

Abstract

Abstract Learning and memory formation in living organisms is an issue under investigation. How learning occurs is not fully understood. Nevertheless, learning and memory are evaluated to correlate with the connective structure between cells. Memory formed in the biological neural network structure is thought to be closely related to cell connections. Biological experiments have been determined connections called motifs, which usually comprise three or four cells and repeat within the network. The connection of these motifs varies as to the status of inter-cellular stimulus. The primary make-up of the biological memory is thought to correlate with such repeated cell connections. For this reason, studies investigate the memory behaviour of the motifs. In this study, some important factors affecting motif-based short- and long-term memory behaviour in biological networks were investigated. For that purpose, the effect of the connection patterns of the motifs on the short- and long-term memory structure was investigated for all three-cell motifs. We used the Hodgkin-Huxley neuron model for cells. Using graph theory, we created three-cell motifs. In the created motifs; The effects of intercellular connection patterns, the type of excitation of cells to each other, and the duration of chemical synaptic stimulation on short- and long-term memory were examined. Based on the data got from the models; We showed that the structure of the motif and the type of stimulus affect directly memory formation in all three-cell motifs. We also showed that the short-term memory duration (in the motif and stimulation conditions) changes with the change of the synaptic stimulation time constant, which models the duration of intercellular communication. At the end of this study, we classified all three-cell motifs for the states that present short- and long-term memory behaviour. We studied the biological events that occur during learning on the model and examined their effects on learning. Consequently, these studies have demonstrated learning about living organisms.