Social-like responses are inducible in asocial Mexican cavefish despite the exhibition of strong repetitive behaviour

  1. Motoko Iwashita
  2. Masato Yoshizawa  Is a corresponding author
  1. University of Hawaii at Manoa, United States


Social behaviour is a hallmark of complex animal systems; however, some species appear to have secondarily lost this social ability. In these non-social species, whether social abilities are permanently lost or suppressed is unclear. The blind cavefish Astyanax mexicanus is known to be asocial. Here, we reveal that cavefish exhibited social-like interactions in familiar environments but suppressed these interactions in stress-associated unfamiliar environments. Furthermore, the level of suppression in sociality was positively correlated with that of stereotypic repetitive behaviour, as seen in mammals. Treatment with a human antipsychotic drug targeting the dopaminergic system induced social-like interactions in cavefish, even in unfamiliar environments, while reducing repetitive behaviour. Overall, these results suggest that the antagonistic association between repetitive and social-like behaviours is deeply shared from teleosts through mammals.

Data availability

All data generated and analyzed during this study are included in the supplementary Source Data file. Program scripts/codes are available in the public data depository ( All raw video data are available upon request. Sample video files are available at

The following data sets were generated

Article and author information

Author details

  1. Motoko Iwashita

    National Institute of Mental Health, University of Hawaii at Manoa, Honolulu, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6653-6823
  2. Masato Yoshizawa

    School of Life Sciences, University of Hawaii at Manoa, Honolulu, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8455-8252


National Institutes of Health (P20GM125508)

  • Masato Yoshizawa

Hawaii Community Foundation (18CON-90818)

  • Masato Yoshizawa

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Nicolas Rohner, Stowers Institute for Medical Research, United States


Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (#17-2560) of the University of Hawaii at Manoa. The protocol was approved by the Committee on the Ethics of Animal Experiments of the University of Hawaii at Manoa (Permit Number: A3423-01). All vital-dye imaging were performed under ice-cold MS222 anesthesia, and every effort was made to minimize suffering

Version history

  1. Preprint posted: August 20, 2020 (view preprint)
  2. Received: July 24, 2021
  3. Accepted: September 17, 2021
  4. Accepted Manuscript published: September 20, 2021 (version 1)
  5. Version of Record published: October 8, 2021 (version 2)


© 2021, Iwashita & Yoshizawa

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.


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  1. Motoko Iwashita
  2. Masato Yoshizawa
Social-like responses are inducible in asocial Mexican cavefish despite the exhibition of strong repetitive behaviour
eLife 10:e72463.

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