Neurotransmitter-Induced Excitatory and Inhibitory Functions in Artificial Synapses

Neurotransmitters control signal transmission in the nervous system. The signals of neuron cells can be excited or inhibited based on the types of neurotransmitters that are released from pre-synaptic neurons. The balance of the excitatory and inhibitory synaptic responses has important implications for the versatility, plasticity, and parallel computing characteristics of the nervous system. Emulating the excitatory-inhibitory balancing characteristics is one way to establish the versatility and plasticity characteristics of the brain. In this study, the authors develop artificial synapses to emulate the excitatory and inhibitory functions of biological synapses using electrochemical reactions between the channel and neurotransmitter solutions. The devices show excitatory and inhibitory characteristics depending on types of neurotransmitter solutions. The interaction between these two types of synaptic responses is employed for emulating the excitatory-inhibitory balance characteristics. The devices emulate the multifunctional characteristics of biological synapses, resulting in their potential for use in bio-realistic neuromorphic devices.