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Home / Equine Research Bank / PLoS One / EquiFACS: The Equine Facial Action Coding System.
PloS one2015; 10(8); e0131738; doi: 10.1371/journal.pone.0131738

EquiFACS: The Equine Facial Action Coding System.

Abstract: Although previous studies of horses have investigated their facial expressions in specific contexts, e.g. pain, until now there has been no methodology available that documents all the possible facial movements of the horse and provides a way to record all potential facial configurations. This is essential for an objective description of horse facial expressions across a range of contexts that reflect different emotional states. Facial Action Coding Systems (FACS) provide a systematic methodology of identifying and coding facial expressions on the basis of underlying facial musculature and muscle movement. FACS are anatomically based and document all possible facial movements rather than a configuration of movements associated with a particular situation. Consequently, FACS can be applied as a tool for a wide range of research questions. We developed FACS for the domestic horse (Equus caballus) through anatomical investigation of the underlying musculature and subsequent analysis of naturally occurring behaviour captured on high quality video. Discrete facial movements were identified and described in terms of the underlying muscle contractions, in correspondence with previous FACS systems. The reliability of others to be able to learn this system (EquiFACS) and consistently code behavioural sequences was high--and this included people with no previous experience of horses. A wide range of facial movements were identified, including many that are also seen in primates and other domestic animals (dogs and cats). EquiFACS provides a method that can now be used to document the facial movements associated with different social contexts and thus to address questions relevant to understanding social cognition and comparative psychology, as well as informing current veterinary and animal welfare practices.
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Publication Date: 2015-08-05 PubMed ID: 26244573PubMed Central: PMC4526551DOI: 10.1371/journal.pone.0131738Google Scholar: Lookup
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Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research article presents the development of EquiFACS, a Facial Action Coding System for horses, which was created by studying their facial musculature and movements. The system can be used in a wide range of studies and can be learned easily by people with no previous experience with horses.

Development of the Equine Facial Action Coding System (EquiFACS)

  • The research team developed EquiFACS by studying the anatomy of horse facial musculature and analyzing the facial movements in high-quality videos of naturally occurring horse behavior.
  • They successfully described discrete facial movements in terms of the underlying muscle contractions, in line with previous Facial Action Coding Systems.
  • This process facilitated the categorization and documentation of all possible horse facial movements, providing a comprehensive and systematic approach to analyse horse facial expressions.

Reliability of EquiFACS

  • The developed system proved to be reliable as it could be learned and applied consistently by individuals with diverse backgrounds, including those with no previous experience with horses.
  • This highlights the system’s accessibility and potential for widespread use in various research areas.

Identification of a Wide Range of Facial Movements

  • The researchers identified a wide variety of facial movements in horses, which included movements similar to those observed in primates, dogs, and cats.
  • This commonality suggests the potential for comparative studies across different species.

Potential Applications of EquiFACS

  • EquiFACS is not confined to a particular context or situation, instead it can be applied to document the facial movements associated with different social contexts.
  • It can thus contribute to studies aimed at understanding social cognition and comparative psychology and can offer valuable insights into horse behavior in different situations and emotional states.
  • In addition, EquiFACS can be used to inform veterinary procedures and animal welfare practices, potentially improving the care and understanding of horses and their emotional states.

Cite This Article

APA
Wathan J, Burrows AM, Waller BM, McComb K. (2015). EquiFACS: The Equine Facial Action Coding System. PLoS One, 10(8), e0131738. https://doi.org/10.1371/journal.pone.0131738

Publication

PloS one
ISSN: 1932-6203
NlmUniqueID: 101285081
Country: United States
Language: English
Volume: 10
Issue: 8
Pages: e0131738
PII: e0131738

Researcher Affiliations

Wathan, Jen
  • Mammal Communication and Cognition Research, School of Psychology, University of Sussex, Brighton, United Kingdom.
Burrows, Anne M
  • Centre for Comparative and Evolutionary Psychology, Department of Psychology, University of Portsmouth, Portsmouth, United Kingdom.
Waller, Bridget M
  • Department of Physical Therapy, Duquesne University, Pittsburgh, Pennsylvania, United States of America.
McComb, Karen
  • Mammal Communication and Cognition Research, School of Psychology, University of Sussex, Brighton, United Kingdom.

MeSH Terms

  • Animals
  • Emotions / physiology
  • Face
  • Facial Expression
  • Facial Muscles / physiology
  • Horses
  • Social Behavior
  • Species Specificity

Grant Funding

  • Biotechnology and Biological Sciences Research Council

Conflict of Interest Statement

The authors have declared that no competing interests exist.

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