Contribution of visual and proprioceptive information to the precision of reaching movements.
Ren et al. (J Neurophysiol 96:1464-1477, 2006) found that saccades to visual targets became less accurate when somatosensory information about hand location was added, suggesting that saccades rely mainly on vision. We conducted two kinematic experiments to examine whether or not reaching movements would also show such strong reliance on vision. In Experiment 1, subjects used their dominant right hand to perform reaches, with or without a delay, to an external visual target or to their own left fingertip positioned either by the experimenter or by the participant. Unlike saccades, reaches became more accurate and precise when proprioceptive information was available. In Experiment 2, subjects reached toward external or bodily targets with differing amounts of visual information. Proprioception improved performance only when vision was limited. These results indicate that the reaching system has a better internal model for limb positions than does the saccade system.
Monaco
Simona
S
Department of Psychology, The University of Western Ontario, London, ON, N6A 5C2, Canada. simona.monaco@gmail.com
Króliczak
Gregory
G
Quinlan
Derek J
DJ
Fattori
Patrizia
P
Galletti
Claudio
C
Goodale
Melvyn A
MA
Culham
Jody C
JC
D000328:Adult; D001696:Biomechanical Phenomena; D005260:Female; D007839:Functional Laterality; D006225:Hand; D006801:Humans; D008297:Male; D008568:Memory; D009043:Motor Activity / Q000502:physiology; D010775:Photic Stimulation; D011434:Proprioception; D011597:Psychomotor Performance / Q000502:physiology; D011601:Psychophysics; D013997:Time Factors; D014796:Visual Perception; D055815:Young Adult