Dogs can discriminate human smiling faces from blank expressions

Abstract

Dogs have a unique ability to understand visual cues from humans. We investigated whether dogs can discriminate between human facial expressions. Photographs of human faces were used to test nine pet dogs in two-choice discrimination tasks. The training phases involved each dog learning to discriminate between a set of photographs of their owner’s smiling and blank face. Of the nine dogs, five fulfilled these criteria and were selected for test sessions. In the test phase, 10 sets of photographs of the owner’s smiling and blank face, which had previously not been seen by the dog, were presented. The dogs selected the owner’s smiling face significantly more often than expected by chance. In subsequent tests, 10 sets of smiling and blank face photographs of 20 persons unfamiliar to the dogs were presented (10 males and 10 females). There was no statistical difference between the accuracy in the case of the owners and that in the case of unfamiliar persons with the same gender as the owner. However, the accuracy was significantly lower in the case of unfamiliar persons of the opposite gender to that of the owner, than with the owners themselves. These results suggest that dogs can learn to discriminate human smiling faces from blank faces by looking at photographs. Although it remains unclear whether dogs have human-like systems for visual processing of human facial expressions, the ability to learn to discriminate human facial expressions may have helped dogs adapt to human society.

This is a preview of subscription content, log in to check access.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

References

  1. Abrantes R (1987) The expression of emotions in man and canid. J Small Anim Pract 28:1030–1036

    Article  Google Scholar 

  2. Adachi I, Kuwahata H, Fujita K (2007) Dogs recall their owner’s face upon hearing the owner’s voice. Anim Cogn 10:17–21

    PubMed  Article  Google Scholar 

  3. Bradshaw JWS, Nott HMR (1995) Social and communication behaviour of companion dogs. The domestic dog: its evolution, behaviour and interactions with people. In: Serpell JA (ed) The domestic dog, its evolution, behavior and interactions with people, 11th edn. Cambridge University Press, Cambridge, pp 115–130

    Google Scholar 

  4. Call J, Brauer J, Kaminski J, Tomasello M (2003) Domestic dogs (Canis familiaris) are sensitive to the attentional state of humans. J Comp Psychol 117:257–263

    PubMed  Article  Google Scholar 

  5. Cellerino A, Borghetti D, Sartucci F (2004) Sex differences in face gender recognition in humans. Brain Res Bull 63:443–449

    PubMed  Article  Google Scholar 

  6. Ekman P, Friesen WV (1975) Unmasking the face: a guide to recognizing emotions from facial clues. Prentice-Hall Englewood Cliffs, NJ

    Google Scholar 

  7. Fox MW (1970) A comparative study of the development of facial expressions in canids; wolf, coyote and foxes. Behaviour 36:49–73

    Article  CAS  Google Scholar 

  8. Gacsi M, Miklosi A, Varga O, Topal J, Csanyi V (2004) Are readers of our face readers of our minds? Dogs (Canis familiaris) show situation-dependent recognition of human’s attention. Anim Cogn 7:144–153

    PubMed  Article  Google Scholar 

  9. Guo K, Meints K, Hall C, Hall S, Mills D (2009) Left gaze bias in humans, rhesus monkeys and domestic dogs. Anim Cogn 12:409–418

    PubMed  Article  Google Scholar 

  10. Hare B, Call J, Tomasello M (1998) Communication of food location between human and dog (Canis familiaris). Evol Commun 2:137–159

    Article  Google Scholar 

  11. Heffner H (1975) Perception of biologically meaningful sounds by dogs. J Acoust Soc Am 58:S124

    Article  Google Scholar 

  12. Kanazawa S (1996) Recognition of facial expressions in a Japanese monkey (Macaca fuscata) and humans (Homo sapiens). Primates 37:25–38

    Article  Google Scholar 

  13. Lore RK, Eisenberg FB (1986) Avoidance reactions of domestic dogs to unfamiliar male and female humans in a kennel setting. Appl Anim Behav Sci 15:261–266

    Article  Google Scholar 

  14. Morisaki A, Takaoka A, Fujita K (2009) Are dogs sensitive to the emotional state of humans? J Vet Behav Clin Appl Res 4:49

    Article  Google Scholar 

  15. Nagasawa M, Kikusui T, Onaka T, Ohta M (2009) Dog’s gaze at its owner increases owner’s urinary oxytocin during social interaction. Horm Behav 55:434–441

    PubMed  Article  CAS  Google Scholar 

  16. Racca A, Amadei E, Ligout S, Guo K, Meints K, Mills D (2010) Discrimination of human and dog faces and inversion responses in domestic dogs (Canis familiaris). Anim Cogn 13:525–533

    PubMed  Article  Google Scholar 

  17. Range F, Aust U, Steurer M, Huber L (2008) Visual categorization of natural stimuli by domestic dogs. Animal Cognit 11:339–347

    Article  Google Scholar 

  18. Schwab C, Huber L (2006) Obey or not obey? Dogs (Canis familiaris) behave differently in response to attentional states of their owners. J Comp Psychol 120:169–175

    PubMed  Article  Google Scholar 

  19. Takaoka A, Morisaki A, Fujita K (2009) Intermodal representation in dogs. J Vet Behav Clin Appl Res 4:54–55

    Article  Google Scholar 

  20. Udell MAR, Dorey NR, Wynne CDL (2010) What did domestication do to dogs? A new account of dogs’ sensitivity to human actions. Biol Rev 85:327–345

    PubMed  Article  Google Scholar 

  21. Vas J, Topál J, Gácsi M, Miklósi A, Csányi V (2005) A friend or an enemy? Dogs’ reaction to an unfamiliar person showing behavioural cues of threat and friendliness at different times. Appl Anim Behav Sci 94:99–115

    Article  Google Scholar 

  22. Viranyi Z, Topál J, Gácsi M, Miklósi A, Csanyi V (2004) Dogs respond appropriately to cues of humans’ attentional focus. Behav Process 66:161–172

    Article  Google Scholar 

  23. Wells DL (2003) Lateralised behaviour in the domestic dog, Canis familiaris. Behav Process 61:27–35

    Article  Google Scholar 

  24. Wobber V, Hare B, Koler-Matznick J, Wrangham R, Tomasello M (2009) Breed differences in domestic dogs’ (Canis familiaris) comprehension of human communicative signals. Interact Stud 10:206–224

    Article  Google Scholar 

Download references

Author information

Affiliations

Authors

Corresponding author

Correspondence to Takefumi Kikusui.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Test phase: Ten sets of photographs of the smiling face and blank face of the owner were presented (OW session). The photographs were changed once each trial. The smiling face photographs were the S+ (MPG 16397 kb)

Control phase: Photographs of the same smiling face of the owner were presented simultaneously (SS session). The S+ was chosen randomly once each trial (MPG 16197 kb)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Nagasawa, M., Murai, K., Mogi, K. et al. Dogs can discriminate human smiling faces from blank expressions. Anim Cogn 14, 525–533 (2011). https://doi.org/10.1007/s10071-011-0386-5

Download citation

Keywords

  • Dog
  • Human facial expression
  • Two-choice discrimination tasks
  • Visual discrimination