Computer-generated 3-D reconstruction from case M25, in which FR and BDA was injected in corresponding whisker representations in SI and MI, respectively. Several largely segregated clusters of labeling are observed within the ipsilateral pontine nuclei. The labeled clusters together form a ring-like volume in the pontine nuclei. Sparse labeling is observed in the contralateral pontine nuclei, at locations mirroring the ipsilateral labeling. This case is documented in accompanying paper by Leergaard et al (2004). Scale bars, 500 µm.