u201d is meant the regeneration or reformation and refunctionalization of synapses after nerve cells have ceased to exhibit normal synapses as a result of a neurodegenerative disease numerous neurodegenerative diseases affect humans particularly the elderly and result in an enormous cost both economically and socially to society among such diseases alzheimer disease is perhaps the most pervasive but others such as senile dementia pick 39 s disease and parkinson 39 s disease are also the result of the degeneration of the nervous system using a pure neuronal system i e primary hippocampal neurons in culture the instant invention has been able to establish the critical role of synapsin proteins and especially synapsin ii in synaptogenesis and particularly in synapse maintenance and restoration administration of synapsin ii antisense oligonucleotides to cultured hippocampal neurons at different stages of development results in the suppression of the expression of synapsin ii further examination has focused on the consequences of synapsin ii depletion on neuronal development with special reference to neurite outgrowth neuronal morphology and synaptic density in the therapeutic method of the present invention an agent is administered in an amount sufficient to maintain and or restore synapses to the patient under treatment several agents can be utilized to accomplish this method in a first embodiment of the present invention the agent can be a synapsin cdna or protein or an active fragment thereof which is administered into the patient 39 s nervous system to effect the desired synapsin maintenance and or restoration both synapsin cdna and synapsin.