Subitizing is a fast and accurate process of enumerating small quantities. Most studies explore visual enumeration. Thus, the question is whether subitizing is a general process that occurs regardless of modality presentation. The literature on tactile subitizing is sparse and the findings are diverse. According to our knowledge, no study has compared visual and tactile modalities using as similar a methodology as possible. We used a within-participants design to compare visual and tactile enumeration using both hands, and to explore the effect of numerosity range (NR) on enumeration. In Experiment 1, using a custom-made vibro-tactile apparatus, we replicated results of Cohen, Naparstek, and Henik (2014, Acta Psychologica, 150C, 26a??34) and again found a moderate increase in RT for up to 4 stimuli and then a decrease for 5 stimuli. In Experiment 2, we compared NR 1-5 and 1-10 in tactile and visual enumeration. The results showed that enumeration for NR 1-5 was faster than for NR 1-10, especially for numerosities 4 and 5. Within NR 1-10, in the visual modality the subitizing range was 4, counting ranged from 5 to 9, and there was an end effect of 10 dots. In contrast, in the tactile modality, when excluding one-hand arrangements, the subitizing range was 2, the counting range was from 3 to 5, there was an acceleration of counting from 5 and on, and there was an end effect for 10 stimuli that was stronger than for 10 visual stimuli. We suggest that NR influences enumeration and that number-hand association (i.e., resulting from finger counting) influences enumeration, resulting in (a) faster counting for large numerosities in the tactile modality and (b) a different RT pattern for each modality.
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