Picture-digit differences in processing clock times.

Clock times displayed as digits and as clockfaces were used as stimuli in a series of experiments that tested the hypothesis that a common numerical code was used for processing clock times. Whether the task involved reading times or making comparative judgments of early/late or same/different, digits were always processed faster than clockfaces . The size of the format effect varied, however, with the processing demands of the task and with times at specific locations on the clockface . Also, automatic processing of times presented as clockfaces interfered with comparative judgments made with digits, but digital distractors were not found to interfere with judgments made to times as clockfaces . The findings are discussed within the context of picture-word differences in rate of access to articulatory and semantic codes. Conclusions are also made regarding the relative efficiency of displaying times digitally and in the form of clockfaces .