Movement in decline? Oscillatory movement displacement thresholds increase with ageing.
Displacement thresholds for continuous oscillatory movement were determined for ten subjects in each of three age groups--20-23, 40-55 and 60-80 years. Oscillation frequencies of 1, 2, 3, 5, 8, 13 and 20 Hz were used, all subjects having a corrected visual acuity of 6/5. A randomized block factorial design of analysis of variance revealed significant effects of both temporal frequency of oscillation (F6,189 = 4.10, p less than 0.001) and age (F2,189 = 46.98, p much less than 0.001). The deterioration in movement sensitivity occurs equally at both high and low temporal frequencies--no significant interaction effects being revealed (F12,189 = 0.45, p = not significant). The frequency effects are ascribed to underlying mechanisms mediating movement perception. Reasons for decreased movement sensitivity with increasing age are discussed.
Buckingham
T
T
School of Optometry, University of Bradford, U.K.
Whitaker
D
D
Banford
D
D
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D005403:Fixation, Ocular; D006801:Humans; D008875:Middle Aged; D009039:Motion Perception / Q000502:physiology*; D012684:Sensory Thresholds / Q000502:physiology; D013997:Time Factors