What will be the Target set for Epilepsy Detection in Backpropagation NN

I want to train a neural network using Backpropagation Algorithm for Epilepsy Detection. I have already extracted features from data set of the healthy and unhealthy brain and now they will be used for training. But I am not able to figure out the target values for training. Can anyone help me to get the idea about what should be the target set in such type of training and how its values are decided? It would be a great help. Thanks in Advance.