Document Type : Full Research Paper


1 M.Sc., Institute of Medical Science and Technology (IMSAT), Shahid Beheshti University, Tehran, Iran

2 Assistant Professor, Institute of Medical Science and Technology (IMSAT), Shahid Beheshti University, Tehran, Iran



The human body has five main senses of sight, hearing, taste, smell and touch. The defective performance of any of these senses causes us to solve this problem and use technology for this purpose. The sense of hearing is no exception and several attempts have been made to restore it, which has led to the design of various implants. In this study, with the aim of investigating the function of the auditory midbrain implant (AMI) in restoring hearing ability, the cat’s auditory system has been stimulated in acoustic and electrical stimulation. Electrical stimuli are the result of AMI injecting current into the central nucleus of the inferior colliculus (ICC) and acoustic stimuli are the result of pure tone sound in the cat’s ear. After stimulation, responses were extracted from the primary auditory cortex of the cat's brain. Finally, a neural network (NN) with backpropagation-based modelling has been used. After data acquisition and processing, it was clear that AMI successfully stimulated the ICC. But it is associated with delays during stimulation. After model creation, it was found that the Levenberg-Marquardt algorithm with 10 neurons in the hidden layer had the best performance compared to the others with an error of 0.009. Also, both models show similar behaviour to frequency changes, but the electrical model at a constant frequency shows a bigger response at the output. Finally, the interval between the transmission of the neural message from the cochlear nucleus to the inferior colliculus was calculated at 9 milliseconds.


Main Subjects

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