Gesture size affects numerical estimates in quantifier comprehension

Area of Science:

• Cognitive Psychology
• Linguistics
• Nonverbal Communication

Background:

• Numerical magnitude is often conceptualized spatially.
• Co-speech gestures, like expansive hand movements for larger quantities, reflect this spatial-numerical association.
• Research has primarily focused on gesture production, not interpretation, of numerical expressions.

Purpose of the Study:

• To investigate if co-speech gestures influence the interpretation of imprecise numerical expressions.
• To examine the effect of inward- and outward-directed gestures on the comprehension of the quantifier 'several'.
• To test the hypothesis that gesture modulates quantity perception.

Main Methods:

• Three preregistered experiments were conducted.
• Participants observed speakers producing gestures (inward, outward, or none) while using the quantifier 'several'.
• Comprehenders' quantity estimates associated with 'several' were recorded.

Main Results:

• Outward-directed gestures (hands moving apart) led to significantly higher quantity estimates for 'several'.
• Inward-directed gestures (hands moving together) did not significantly differ from no gesture.
• Gesture significantly modulates the interpretation of underspecified numerical quantifiers.

Conclusions:

• Manual gestures play a crucial role in the pragmatic interpretation of numerical quantifiers.
• Spatial conceptualization of number extends to how gestures influence numerical understanding.
• Findings have implications for numerical cognition, multimodal communication, and pragmatics.