A review of plasticity induced by auditory and visual tetanic stimulation in humans

Long‐term potentiation is a form of synaptic plasticity thought to play an important role in learning and memory. Recently noninvasive methods have been developed to induce and measure activity similar to long‐term potentiation in humans. Sensory tetani (trains of quickly repeating auditory or visual stimuli) alter the electroencephalogram in a manner similar to electrical stimulation that results in long‐term potentiation. This review briefly covers the development of long‐term potentiation research before focusing on in vivo human studies that produce long‐term potentiation‐like effects using auditory and visual stimulation. Similarities and differences between traditional (animal and brain tissue) long‐term potentiation studies and human sensory tetanization studies will be discussed, as well as implications for perceptual learning. Although evidence for functional consequences of sensory tetanization remains scarce, studies involving clinical populations indicate that sensory induced plasticity paradigms may be developed into diagnostic and research tools in clinical settings. Individual differences in the effects of sensory tetanization are not well‐understood and provide an interesting avenue for future research. Differences in effects found between research groups that have emerged as the field has progressed are also yet to be resolved. Sensory tetanic stimulation noninvasively elicits LTP‐like responses in humans and may induce plasticity similar to that induced by electrical tetanization. LTP‐like plasticity is a potential mechanism underlying perceptual learning. Varying results between research groups that have emerged as the field has progressed are yet to be resolved. Individual differences in these effects are also not well‐understood. Understanding these differences is vital if the paradigm is to have clinical value.