A Visual Retention Test for Clinical Use

The visual retention test to be described here was developed as a practical means of fulfilling what I have long felt to be a need in the usual clinical examination of patients, namely, a short test to supplement the auditory-vocal digit span test in the investigation of immediate memory. The auditory-vocal digit span test, devised in 1887 by Jacobs,1has become a stable feature of most clinical examination schemes. It measures retention or immediate memory, which is justifiably considered to be a significant aspect of mental capacity and one which is especially important clinically because of its close relationship to mental impairment. The test has obvious technical advantages, such as brevity of administration, lack of need for test materials and the objective character of the patient's performance. Nevertheless, while it is a useful single test, both clinical experience and experimental observations indicate that it cannot be considered to be