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One, two, three, many – subitizing in active touch
authors Plaisier, M.A.; Bergmann Tiest, W.M.; Kappers, A.M.L.
source Acta psychologica, Volume: 131, Issue: 2 (2009), pp. 163-170
full text [Full text]
publisher Elsevier
URL publisher [Website publisher]
document type Article
version Publisher version
disciplines Natuur- en sterrenkunde
abstract ‘Subitizing’ refers to rapid and accurate judgement of small numbers of items, while response times and error rates increase rapidly for larger set-sizes. Most enumeration studies have been done in vision. Enumeration studies in touch have mostly involved ‘passive touch’, i.e. touch without active exploration. In daily life a much more common situation is that of ‘active touch’, e.g. when we count the number of coins in our pocket. To investigate numerosity judgement in active touch, we let subjects haptically explore varying numbers of spheres. Our results show that enumeration for up to 3 items is more efficient than for larger numbers of items. We also show that enumeration in this regime was not performed through estimation. Furthermore, it is shown that numerosity information was accessed directly and not through mass or volume cues. Not only do our results show that a haptic version of subitizing exists in active touch, they also suggest similar underlying enumeration mechanisms across different modalities.
keywords Active touch, Subitizing, Numerosity judgement
ISSN 0001-6918