Identification reaction time as a function of target and field object orientation

Four experiments were conducted investigating the effects of (a) target versus field object orientation, (b) target upside up versus target upside down and (c) inverting versus noninverting lenses on object identification reaction time. Inverting versus noninverting lenses had no significant effect. Target versus field orientation was significant when objects commonly found on a desk were used. Target upside up versus upside down was not significant. With letters as target and field objects, orientation was not significant. When the target letters were simply inverted (rotated 180 degrees on the horizontal axis), however, forming nonfamiliar patterns, the target upside up versus upside down was significant, with the upside down condition resulting in a longer mean reaction time. The complexity and similarity of target and field objects is offered as an explanation of the results.