CHANGE IN INFORMATION PROCESSING AND CHANNEL CAPACITY WITH INCREASE IN AGE WAS STUDIED, AND POSSIBLE ALTERING OF THIS RELATIONSHIP WITH A CHANGE IN COMPLEXITY AND DIMENSIONALITY OF THE STIMULUS PRESENTED. VISUAL STIMULI WERE PROJECTED ON A SCREEN TO FOUR GROUPS COMPOSED OF 74 COLLEGE GRADUATES, RANGING IN AGE FROM 23 TO 68 YEARS, IN A SIMULATED CLASSROOM. THREE OF FIVE TESTS WERE PRESENTED TO EACH SUBJECT--SIZE OF DARK SQUARES ON LIGHT BACKGROUND WAS JUDGED IN THREE TESTS, AND LOCATION OF DOT PLACEMENT IN A GRID PATTERN IN TWO TESTS. ABSOLUTE JUDGMENTS WERE USED TO MEASURE JUDGMENTAL DISCRIMINATION ACCURACY. INFORMATION THEORY STATISTICS WERE USED FOR INDIVIDUAL TEST DATA ANALYSIS, AND CONVENTIONAL STATISTICS TO DETERMINE LEVELS OF SIGNIFICANCE OF DATA COLLECTED. IT WAS FOUND THAT PERFORMANCE DECLINED AS AGE INCREASED IN THREE OF THE FIVE TESTS, CONTAINING THE LEAST COMPLEX STIMULUS SITUATION, WHICH WAS CONTRARY TO PREDICTION. IT WAS SPECULATED THAT A HIGHER ANXIETY RATE WAS MANIFESTED DURING EARLY TESTS, AND OLDER SUBJECTS REACHED PEAK PERFORMANCE DURING THE THREE LATER TESTS. ALL SUBJECTS SCORED HIGHER ON THE MULTIDIMENSIONAL STIMULUS PRESENTATIONS (DOT AND SUBJECTS SCORED HIGHER ON THE MULTIDIMENSIONAL STIMULUS PRESENTATIONS (DOT AND GRID). OTHER FINDINGS SHOWED MALES OUTSCORING FEMALES IN ALL TESTS. (PT)