Modelling the coevolution of joint attention and language

Area of Science:

• Evolutionary biology
• Cognitive science
• Computational linguistics

Background:

• Joint attention (JA) is fundamental for social and communicative activities, including language acquisition.
• Humans display significantly higher levels of JA compared to non-human primates, a difference that requires explanation.

Purpose of the Study:

• To propose and test a coevolutionary hypothesis explaining the higher degree of JA in humans.
• To investigate the role of communicative success (CS) in enhancing JA levels during language evolution.

Main Methods:

• Development of a multi-agent computational model to simulate the coevolution of JA and language.
• Modeling JA as a genetically transmitted ability to utilize non-linguistic cues for enhanced comprehension.
• Analysis of simulation results to correlate JA levels with language understandability and CS.

Main Results:

• A positive correlation was observed between the level of JA and the understandability of the emergent language.
• Communicative success (CS) was shown to effectively increase initially low levels of JA to a stable, high level.
• The model supports the 'ratcheting' effect of CS on JA, demonstrating its role in evolutionary enhancement.

Conclusions:

• The coevolutionary hypothesis provides a framework for understanding the human-primate difference in JA.
• Biological evolution, individual learning, and cultural transmission are critical interacting factors in language evolution.
• This perspective highlights the interplay between genetic predispositions and cultural feedback in shaping complex cognitive abilities like JA.