Biochemistry of Short-Term and Long-Term Memory

Memory is provided by changes in synapses in neural circuits: short-term memory - by functional changes in a separate sensory neuron and a separate motor neuron, long-term memory - by structural changes (regrowth of new synapses).During the formation of short-term memory in synapses, cAMP, protein kinase A, are used, which act inside the cell and transmit a signal that cause the release of large amounts of the neurotransmitter glutamate. Two independent mechanisms are involved in the formation of long-term memory: - one triggers a long-term strengthening of synaptic connections, directing protein kinase A to the nucleus, which activates the CREB protein, thereby turning on the structural genes encoding proteins necessary for the growth of new synaptic connections; - the other reinforces the already formed memory, supporting the newly formed synaptic endings, which requires local synthesis of proteins.