Interactions between noise and signal segments at the decision level are task contingent.
The ways in which unattended line segments influence the discrimination of a single line segment on which attention is focused was studied in two experiments which differed only by the task to be performed. In the first experiment subjects had to determine whether a line segment viewed centrally was oriented to the right or to the left with respect to the vertical, and in the second experiment they had to judge its tilt amplitude (45 deg vs. 55 deg to vertical). It appears that line segments surrounding the target segment did not affect subjects' response times in the same way in the two experiments. Results are interpreted in terms of response competition at the decision level.
Dufour
A
A
Université Louis Pasteur, Laboratoire de Psychophysique Sensorielle, Strasbourg, France.
D001288:Attention; D005556:Form Perception / Q000502:physiology*; D006801:Humans; D009949:Orientation; D014795:Visual Pathways / Q000502:physiology