Abstract
The purpose of the study is to determine the defective site along the visual perceptive process, successive process dealing with mental representation and response process underlying the unilateral spatial neglect (USN), and to define the influence of the space given visual stimulation. Five patients with leftside USN from the lesions in the right cerebral hemisphere were examined utilizing of the visual discrimination of pairs of figures. Subjects were required to judge mentally and to answer verbally whether pairs of visually presented figures were same or different each others. These trials were carried out in three different conditions of the space given visual stimulation. In this experiment, all the patients showed positive for USN regardless of the different space given visual stimulation. No prominent influence for the space given visual stimulation was detected. Consequently, these findings are indicating that USN is the result of a disorder in visual perceptive process and/or successive process dealing with mental representation, and it is not adequate to regard response process as the nature of USN. And it is clearly showed that USN is appeared independ-ently of the space given visual stimulation, however, further study should be carried out to answer the question whether the quantity of USN is changed by means of the space given visual stimulation.
