[Characteristics of 3-dimensional representations of brain stem auditory evoked potentials]

The three dimensional Lissajous curves (3 CLT) of orthogonal derivation (vertex Z+; throat Z-) (left mastoïd Y+; right mastoïd Y-) (nasion X+; neck X-) were calculated and recorded by a computer. 3-D curves were computed with an apparent rotation around the vertical axis Z. Through successive exhibition of the "virtual" plots, the observer will remark a spatial representation of the 3-D curve. As in vectocardiography, a careful scrutiny of these curves displays different planar segments. Of the different coordinates specifying planar segments position in space: azimuth and elevation are the most reproducible. This paper describes the graphic and automatic measurements submitted and gives the results obtained from subjects with normal hearing.