How attention is allocated when using haptic touch: Shape feature distinction and discrimination strategy.
This study investigated how attention is allocated by the physical distinction between tactile 2D shape features: Part 1 tested whether certain shape feature distinctions are perceived efficiently (pre-attentively), as opposed to inefficiently (attention dependent). Part 2 explored what discrimination strategies are at use, and with what level of attention (from pre to focused). It was found (Part 1) that the straight line ↔ angle distinction and the curve ↔ straight line distinction are perceived pre-attentively; the angle ↔ curve distinction attention dependent. Furthermore (Part 2), three discrimination strategies were identified: The figure identity strategy has three levels of attention; it ranks a feature conjunction as the most important target-discriminating feature. The global characteristics strategy and the touch vision strategy have two levels of attention; both rank one separate feature as the most important target-discriminating feature. Despite this, they are equally fast, accurate, and after-decision certain.