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Related Experiment Video

Updated: Aug 19, 2025

Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Following the Dynamics of Structural Variants in Experimentally Evolved Populations

Published on: February 3, 2023

Valence-dependent mutation in lexical evolution.

Joshua Conrad Jackson¹, Kristen Lindquist², Ryan Drabble²

¹Kellogg School of Management, Northwestern University, Evanston, IL, USA. joshua.jackson@kellogg.northwestern.edu.

Nature Human Behaviour

|November 28, 2022

Summary

This summary is machine-generated.

Negative words evolve faster than positive words. This study reveals that emotional valence impacts word replacement rates, particularly for adjectives, influencing lexical evolution.

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Area of Science:

Linguistics
Psycholinguistics
Cognitive Science

Background:

Lexical evolution pace is traditionally explained by macro-level factors like word frequency and population size.
The role of cognitive and affective factors in word evolution remains less understood.
Valence, representing the positivity-negativity of concepts, is a key affective factor to investigate.

Purpose of the Study:

To investigate whether emotional valence influences the rate of lexical evolution.
To determine if negative valence correlates with faster word replacement.
To examine how this relationship varies across different word classes (nouns, verbs, adjectives).

Main Methods:

Analysis of cognate replacement rates for 200 concepts across an Indo-European language tree (6,000–10,000 years).
Statistical controls for word frequency and population size.
Experimental validation of word replacement likelihood based on valence.

Main Results:

Negative valence significantly correlates with faster cognate replacement rates.
This association is strongest for adjectives and less consistent for verbs, not significant for nouns.
Experimental data confirm individuals are more prone to replace words for negative concepts.

Conclusions:

Emotional valence is a significant driver of lexical evolution.
Negative valence accelerates word replacement, especially in adjectives, through micro-level variations.
Findings highlight the impact of affect on language change dynamics.