Abstract: | The phenomenon of binaural summation in which the addition of signals presented to the two ears simultaneously takes place at a central level, has been known for many years. It is reasonable to assume that the pattern of summation differs between subjects with central lesions and those with lesions in the peripheral auditory tracts. Various tests have been proposed to aid in locating the site of the lesion which compare the monaural and binaural speech discrimination scoresIn the present work, two of these tests have been examined. Thee group of subjects have been used: (1) a normally hearing group; (2) a group with hearing impairment resulting from cochlea pathology, and (3) a group with hearing impairment resulting from lesions at the level of the cochlear nuclei. The results showed that neither test differentiate between peripheral and cochlear nuclei lesions |