Eye movements to tool images are predicted by frequency of physical experience with the tool
43.3032, Monday, 18-May, 8:30 am - 12:30 pm, Banyan Breezeway
Rafal Skiba1, Jacqueline Snow1; 1Department of Psychology, University of Nevada Reno
Images of manipulable objects, such as tools, attract attention. There has been recent suggestion that it is the ‘graspable’ handle rather than the functional end of action-relevant images that drives attentional capture. Further, the attentional advantage of tools over non-manipulable objects is thought to be attributable to the automatic recruitment of motor-related brain networks, perhaps as a result of previous physical experience with the object. Here we studied observers’ eye-movements to tool images to determine what part of a tool is prioritized, and whether or not gaze patterns are influenced by the frequency of usage of the object. Observers viewed life-sized high-resolution color photographs of a variety of tools for 2 sec each, during which time they completed a speeded classification task. Eye-movements were recorded during the length of the stimulus presentation period. After the experiment subjects rated how frequently they used each item in everyday life –on a scale from daily to yearly. Surprisingly, eye-movements were overwhelmingly biased towards the functional end, rather than the handle of tools: initial fixations were directed to the functional end, and across the whole trial mean fixation duration was longer and the number of fixations greater within the tool’s functional end than the handle. Subsequent regression analyses revealed that the more frequently a tool was used, the more prolonged was the first fixation within the functional end of the tool, and the fewer fixations were made during stimulus presentation. Taken together, these data suggest that it is the functional end of a tool (which specifies the type of action that a tool affords) rather than the handle (which is relevant for grasping and action execution) that attracts eye movements and attention. Critically, we show for the first time a strong predictive relationship between exploratory eye-movements and previous physical experience with manipulable objects.