Neurotransmission and the strength of a connection between neurons can depend on a variety of factors. This includes; the number of synaptic contacts between 2 neurons, the size of post-synaptic depolarization elicited by neurotransmitters and the probability of neurotransmitter release. Many neurological diseases can occur due to defective flow of neurotransmitters at neuronal synapses. This may result in no impulse reaching the post-synaptic neuron and therefore no responses are exerted by the neurotransmitter downstream.
These small molecules are designed to provide inhibit, amplify or modulate neurotransmission of specific receptors. This is key to understanding the root of dysfunctional neurotransmission common to diseases like Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis, muscular dystrophy, pain and other nervous system diseases/disorders.