**3. Different features of intraoperative neurophysiology**

From a conceptual perspective, intraoperative clinical neurophysiology can be divided into two features: mapping and monitoring [47,48]. The characteristics of these features will be briefly described because neithertheir requirements northe expectations associated with each are equivalent. The main differences between the features are the duration of study, the objectives and the modifications introduced to the surgery. However, in clinical practice, both features very often largely overlap or are used at different epochs of the same surgery.
