A STUDY WAS CONDUCTED TO DETERMINE IF ONE'S EXPRESSED CONCEPT OF HIS PERFORMANCE OF CERTAIN SELECTED MOTOR SKILLS IS CHANGED THROUGH THE PROCESS OF VIEWING MOTION PICTURES OF HIMSELF PERFORMING THESE SAME SKILLS. SIXTY-FIVE COLLEGE STUDENTS 17 TO 21 YEARS OF AGE, PARTICIPATED. EACH SUBJECT PERFORMED FIVE MOTOR SKILLS IN SEQUENCE (1) WALKED 30 FEET AND RETURNED, (2) RAN 30 FEET AS FAST AS POSSIBLE AND RETURNED, (3) CAUGHT 5 VOLLEYBALLS THROWN UNDERHAND FROM A DISTANCE OF 15 FEET, (4) THREW 5 BEANBAGS OVERHAND TO A TARGET ON THE WALL 30 FEET DISTANT, AND (5) COMPLETED 3 STANDING BROAD JUMPS. ONLY THE EXPERIMENTAL SUBJECTS WERE FILMED. AFTER FILMING EACH SUBJECT WAS GIVEN A PERCEPTION CHECKLIST TO CLARIFY HOW THE SUBJECT PERCEIVED HIS MOVEMENTS. RESPONSES FROM THE CHECKLIST WERE TALLIED TO DETERMINE THE NUMBER OF POSITIVE AND NEGATIVE RESPONSES. FILMS WERE DEVELOPED AND EACH SUBJECT WAS SHOWN HIS PERFORMANCE IN RELATION TO 3 OTHER SUBJECTS. AFTER 4 WEEKS THE SUBJECTS WERE MEASURED AGAIN. RESULTS INDICATED THAT (1) SUBJECTS HELD CONCEPTS OF THEMSELVES WHICH WERE SPECIFIC TO THE PARTICULAR SKILL BEING PERFORMED, (2) MALES RELY MORE ON THE CUES RECEIVED FROM BODY SENSATION THAN THEY DO ON CUES FROM VISION, AND (3) FEMALES RELY MORE ON VISUAL CUES THAN ON BODY SENSATION. (HB)