Methods to evaluate central hearing deficiencies and to localize brain damage are reviewed beginning with Bocca who showed that patients with temporal lobe tumors made significantly lower discrimination scores in the ear opposite the tumor when speech signals were distorted. Tests were devised to attempt to pinpoint brain damage on the basis of auditory tests; Jerger found that both temporal lobe tumors and brain-stem damage could lead to the same results on the tests. Bocca suggested delivering different signals to the two ears to assess the integration or binaural summation of the central neural system. Matzker suggested two individually meaningless sounds presented simultaneously, one to each ear; a normal system would apparently integrate sounds better. Studies by Bocca, Jerger, Sanchez-Longo, Forster, Matzker, Harris, and Hayashi indicated that subjects with organic symptoms showed poorer integration than subjects without these symptoms; however, it was not clear where binaural integration took place. Conclusions were that Matzker's procedure is probably inadequate as a general test to localize brain damage. More research is indicated as the technique shows promise for studying an organism's binaural integration abilities. (RP)