Abstract
Although the Bender-Gestalt test has proven adequate in differentiating groups of organic from groups of nonorganic Ss, attempts at individual diagnosis have frequently met with failure. Canter's Background Interference Procedure was designed to increase the sensitivity of the Bender test to the discernment of organic brain damage. The purpose of this paper was to check the validity of the Canter procedure, and to investigate its applicability to Hain's scoring system for the Bender test. 20 brain-damaged patients, 20 schizophrenics, and 20 nonorganic, non-brain-damaged patients were matched for age and intelligence. Each of these groups was further divided into outpatients and inpatients All patients were administered the Bender test on the standard white paper, the WAIS vocabulary subtest, and again the Bender test, on paper for the Background Interference Procedure. Significant results were obtained with the Background Interference administration for both Pascal-Suttell's and Hain's scoring systems where the standard administration had failed to yield significance. The tentative criteria proposed by Canter for individual diagnosis, however, were adequate for Pascal-Suttell's scoring system but not for Hain's method. Possible explanations for this disagreement, as well as suggestions for further research, are offered.