TY  - JOUR
PY  - 2010//
TI  - The influence of near threshold visual distractors on perceptual detection and reaching movements
JO  - Journal of Neurophysiology
A1  - Deplancke, A.
A1  - Madelain, L.
A1  - Chauvin, Alan
A1  - Cardoso-Leite, Pedro
A1  - Gorea, Andrei
A1  - Coello, Yann
SP  - 2249
EP  - 2256
VL  - 104
IS  - 4
N2  - Providing evidence against a dissociation between conscious vision for perception and unconscious vision for action, recent studies have suggested that perceptual and motor decisions are based on a unique signal but distinct decisional thresholds. The aim of the present study was to provide a direct test of this assumption in a perceptual-motor dual task involving arm movements. In 300 trials, 10 participants performed speeded pointing movements towards a highly visible target located at 10 degrees from the fixation point and +/-45 degrees from to the body midline. The target was preceded by one or two close to threshold distractor(s) (80ms SOA) presented +/-30 degrees according to the target location. After each pointing movement participants judged whether the distractor was present or not on either side of the target. Results showed a robust reaction time facilitation effect and a deviation towards the distractor when the distractor was both present and consciously perceived (Hit). A small reaction time facilitation was also observed when two distractors were physically present but undetected (Double-Miss) - this facilitation being highly correlated with the physical contrast of the distractors. These results are compatible with the theory proposing that perceptual and motor decisions are based on a common signal but emerge from a contrast dependent fixed threshold for motor responses and a variable context dependent criterion for perceptual responses. This paper thus extends to arm movement control previous findings related to oculomotor control.<p />  <p>Language: en</p>
LA  - en
SN  - 0022-3077
UR  - http://dx.doi.org/10.1152/jn.01123.2009
ID  - ref1
ER  -