Effects of Numerosity Range on Tactile and Visual Enumeration

Area of Science:

• Cognitive Psychology
• Neuroscience
• Haptics

Background:

• Tactile enumeration, the process of determining quantity through touch, is less understood than visual enumeration.
• Numerosity range (NR) and the use of multiple effectors (e.g., both hands) may influence enumeration efficiency.

Purpose of the Study:

• To investigate the impact of numerosity range (NR) on tactile and visual enumeration.
• To explore the role of number-hand associations in tactile enumeration speed.

Main Methods:

• Experiment 1 replicated previous findings on reaction time (RT) in tactile enumeration using a vibro-tactile apparatus.
• Experiment 2 employed a within-participants design comparing NR 1-5 and 1-10 in both tactile and visual enumeration.

Main Results:

• Tactile enumeration was faster for NR 5-1 compared to 1-10, particularly for numerosities 4 and 5.
• In visual enumeration (NR 1-10), subitizing occurred up to 4, counting from 5-9, with an end effect at 10.
• In tactile enumeration (NR 1-10, excluding one-hand arrangements), subitizing was up to 2, counting from 3-5, with accelerated counting from 5 onwards and a pronounced end effect at 10.

Conclusions:

• Numerosity range significantly influences enumeration performance in both tactile and visual modalities.
• Number-hand associations, potentially from finger counting strategies, enhance the speed of tactile enumeration.