 In subsequent work (Romo et al. 2000), the investigators inverted the experiment, using the microstimulation as the sample. In this case, the animals had to remember the information conveyed by the microstimulation (effectively, a hallucination) and then compare it to either a subsequent (a) mechanically generated stimulation on the finger (actual test stimulus) or (b) a microstimulation of S1 as test (i.e., no stimulus). In both cases, performance was similar to earlier results. The striking finding is that behavior could be driven entirely by microstimulation. At least for the tactile stimulations at issue, the animal might have been in the Matrix!