Units-first or tens-first: Does language matter when processing visually presented two-digit numbers?

in Quarterly Journal of Experimental Psychology (2020), 73(5), 726-738

The linguistic structure of number words can influence performance in basic numerical tasks such as mental calculation, magnitude comparison, and transcoding. Especially the presence of ten-unit inversion ... [more ▼]

The linguistic structure of number words can influence performance in basic numerical tasks such as mental calculation, magnitude comparison, and transcoding. Especially the presence of ten-unit inversion in number words seems to affect number processing. Thus, at the beginning of formal math education, young children speaking inverted languages tend to make relatively more errors in transcoding. However, it remains unknown whether and how inversion affects transcoding in older children and adults. Here we addressed this question by assessing two-digit number transcoding in adults and fourth graders speaking French and German, that is, using non-inverted and inverted number words, respectively. We developed a novel transcoding paradigm during which participants listened to two-digit numbers and identified the heard number among four Arabic numbers. Critically, the order of appearance of units and tens in Arabic numbers was manipulated mimicking the "units-first" and "tens-first" order of German and French. In a third "simultaneous" condition, tens and units appeared at the same time in an ecological manner. Although language did not affect overall transcoding speed in adults, we observed that German-speaking fourth graders were globally slower than their French-speaking peers, including in the "simultaneous" condition. Moreover, French-speaking children were faster in transcoding when the order of digit appearance was congruent with their number-word system (i.e., "tens-first" condition) while German-speaking children appeared to be similarly fast in the "units-first" and "tens-first" conditions. These findings indicate that inverted languages still impose a cognitive cost on number transcoding in fourth graders, which seems to disappear by adulthood. They underline the importance of language in numerical cognition and suggest that language should be taken into account during mathematics education. [less ▲]

Why do temporal generalization gradients change when people make decisions as quickly as possible?

in Quarterly Journal of Experimental Psychology (2011), 64(8), 1646-1664

Three experiments investigated temporal generalization performance under conditions in which participants were instructed to make their decisions as quickly as possible (speed), or were allowed to take ... [more ▼]

Three experiments investigated temporal generalization performance under conditions in which participants were instructed to make their decisions as quickly as possible (speed), or were allowed to take their time (accuracy). A previous study (Klapproth & Müller, 2008) had shown that under speeded conditions people were more likely to confuse durations shorter than the standard with the standard than in the accuracy conditions, and a possible explanation of this result is that longer stimulus durations are "truncated" (i.e., people make a judgement about them before they have terminated, thereby shortening their effective duration) and that these truncated durations affect the standard used for the task. Experiment 1 investigated performance under speed and accuracy conditions when comparison durations were close to the standard or further away. No performance difference was found as a function of stimulus spacing, even though responses occurred on average before the longest durations had terminated, but this lack of effect was attributed to "task difficulty" effects changing decision thresholds. In Experiment 2, the standard duration was either the longest or the shortest duration in the comparison set, and differences between speed and accuracy groups occurred only when the comparisons were longer than the standard, supporting the "truncation" hypothesis. A third experiment showed that differences between speed and accuracy groups only occurred if some memory of the standard that was valid for more than one trial was used. In general, the results suggest that the generalization gradient shifts in speeded conditions occur because of truncation of longer comparison durations, which influences the effective standard used for the task. [less ▲]

Temporal generalization under time pressure in humans.

in Quarterly Journal of Experimental Psychology (2008), 61

Two experiments investigated the effect of encoding two standard intervals on the performance in a temporal generalization task. Previous research has suggested that when individuals compare current time ... [more ▼]

Two experiments investigated the effect of encoding two standard intervals on the performance in a temporal generalization task. Previous research has suggested that when individuals compare current time intervals with a standard encoded within both the auditory and the visual modality, they apparently use both the auditorily and the visually encoded standard for comparison so that each interval was compared with a “mixture” of both standard representations. However, the results of this study showed that memory mixing also happened within a pure visual modality. Moreover, it could be shown that the occurrence of memory mixing depended on instructional ambiguity. If in the training phase both standard durations were erroneously declared to be the same, memory mixing did occur in the testing phase. If, however, both standard durations were described as being different, memory mixing was not observed. [less ▲]