Iconicity emerges and is maintained in spoken language.

Area of Science:

• Psycholinguistics
• Evolutionary Linguistics
• Cognitive Science

Background:

• Iconicity, the resemblance between linguistic signs and their referents, aids language learning and processing.
• Previous research suggests iconicity exists in natural languages, but its emergence and maintenance are debated.
• This study investigates shape and motion iconicity, two key forms of non-arbitrary word-sound mappings.

Purpose of the Study:

• To determine if iconicity emerges spontaneously in novel language creation.
• To investigate whether iconicity is maintained across generations of language users.
• To explore the role of referential pressures in the cultural evolution of language.

Main Methods:

• Experiment 1: Participants generated novel labels for visual shapes (round/spiky) and movements (long/short) via text and speech.
• Experiment 2: Simulated language change using iterated learning to track iconicity across simulated generations.
• Both text-based and speech-based modalities were used across experiments.

Main Results:

• Participants' novel labels showed consistent shape and motion iconicity, aligning with prior findings.
• Iterated learning demonstrated that both shape and motion iconicity were introduced and maintained over simulated language change.
• Iconicity emerged even in unconstrained labeling tasks and persisted through generations.

Conclusions:

• Iconicity emerges spontaneously and is maintained in language through cultural evolution.
• These findings support the hypothesis that referential pressures favor iconic forms in language.
• Iconicity's prevalence across languages may be explained by these evolutionary pressures, with implications for language origin theories.