IT HAS BEEN ESTIMATED THAT BETWEEN 3 AND 15 PERCENT OF ALL CHILDREN IN THE UNITED STATES SUFFER FROM MINIMAL BRAIN DYSFUNCTION, A CONDITION CHARACTERIZED BY DISABILITIES INVOLVING THE CNS AND ITS PROCESSING OF SENSORY INFORMATION. THE HANDICAPS THAT CAN RESULT FROM THIS CONDITION INCLUDE INABILITY TO WRITE AND SPELL, READING PROBLEMS, AUDITORY AND VISUAL-MOTOR PERCEPTUAL DIFFICULTY, AND HYPERACTIVITY. OBSERVATIONS OF A SUPRISINGLY LARGE NUMBER OF CONGENITAL ANOMALIES, ESPECIALLY ASYMMETRICAL EAR PLACEMENT, IN DELINQUENT CHILDREN AND OTHER OBSERVATIONS LINKING EAR ASYMMETRY TO PARENTAL BRAIN DAMAGE LED TO A STUDY IN WHICH EAR PLACEMENT WAS ASSESSED IN 408 CHILDREN. ASYMMETRY WAS FOUND IN 96.2 PERCENT OF MENTALLY RETARDED CHILDREN, 92 PERCENT OF LEARNING-DISABLED CHILDREN, 78.8 PERCENT OF ACADEMIC NONACHIEVERS, 78 PERCENT OF JUVENILE DELINQUENTS, 73 PERCENT OF EMOTIONALLY DISTURBED CHILDREN, 67.8 PERCENT OF PATIENTS IN A CHILDREN'S HOSPITAL, AND 29 PERCENT OF A CONTROL GROUP OF PUBLIC SCHOOL CHILDREN. IN ANOTHER STUDY, EAR ASYMMETRY WAS CORRELATED WITH CNS DYSFUNCTION (AS INDICATED BY VISUAL-MOTOR PERCEPTUAL DIFFICULTY) IN 16 CHILDREN AND 6 ADULTS. BOTH CNS DYSFUNCTION AND ASYMMETRY WERE FOUND IN 15 SUBJECTS, ASYMMETRY WITH NO DYSFUNCTION IN 2 SUBJECTS, SYMMETRY AND CNS DYSFUNCTION IN 1, AND SYMMETRY AND NO DYSFUNCTION IN 4. OBSERVING EAR PLACEMENT APPEARS TO BE A SIMPLE, RELATIVELY RELIABLE WAY TO SCREEN CHILDREN FOR CNS DYSFUNCTION. SUCH A TECHNIQUE COULD FACILITATE EARLY DIAGNOSIS, WHICH IN TURN COULD PREVENT THE REPEATED FRUSTRATIONS AND FAILURES THAT OFTEN CULMINATE IN BEHAVIORAL PROBLEMS FOR CHILDREN WITH CNS DYSFUNCTION. (LKM)