Whole-nerve cuff electrodes can be used to record electrical nerve activity
in peripheral nerves and are suitable for chronic implantation in animals
or humans. If the whole nerve innervates multiple target organs or muscles
then the recorded activity will be the superposition of the activity of dif
ferent nerve fibers innervating these organs. In certain cases it is desira
ble to monitor mixed nerve activity and to determine the origin (modality)
of the recorded activity. A method using the autocorrelation function of re
corded nerve activity and an artificial neural network was developed to cla
ssify the modality of nerve signals. The method works in cases where differ
ent end organs are innervated by nerve fibers having different diameter dis
tributions. The electrical activity in the cat SI sacral spinal root was re
corded using a cuff electrode during the activation of cutaneous, bladder,
and rectal mechanoreceptors. Using the classification method, 87.5% of nerv
e signals were correctly classified This result demonstrates the effectiven
ess of the neural network classification method to determine the modality o
f the nerve activity arising from activation of different receptors.