An EEG trace from the olfactory system of the brain of a rat,
during an epileptic seizure. The trajectory of a
point moving through this space in time traces the subspace that is occupied by
a strange attractor. We have colored it red when the fourth variable is negative
and blue-white when it is positive. The Hausdorff dimension
is reduced to 2.52, and the structure of the strange attractor
appears to be that of a 2-torus.