A subtle yet ubiquitous feature of the human face is eye glint—specular reflections from the surface of the eye that vary with the position of light sources in the environment. This study tested whether eye glint influences face perception, particularly in how observers perceive the gaze direction of a person they are viewing. Adult participants viewed computer-rendered face images that varied in eye direction, head rotation, and illumination. The presence of eye glint had little influence on the accuracy or precision of perceived gaze direction when faces were viewed under simplified conditions. However, biases in perceived gaze direction caused by changes in head orientation or illumination direction were reduced when eye glint was present relative to when it was absent. This suggests that eye glint can help an observer to maintain constancy in gaze perception despite variability in the appearance of the eye region that occurs across viewing conditions.
AdamsW. J.ElderJ. H. (2014). Effects of specular highlights on perceived surface convexity. PLoS Computational Biology, 10(5), Article e1003576. https://doi.org/10.1371/journal.pcbi.1003576
2.
AlaisD.KongG.PalmerC.CliffordC. (2018). Eye gaze direction shows a positive serial dependency. Journal of Vision, 18(4), Article 11. https://doi.org/10.1167/18.4.11
3.
AndoS. (2002). Luminance-induced shift in the apparent direction of gaze. Perception, 31(6), 657–674. https://doi.org/10.1068/p3332
4.
AndoS. (2004). Perception of gaze direction based on luminance ratio. Perception, 33(10), 1173–1184. https://doi.org/10.1068/p5297
5.
AnstisS. (2018). The role of the pupil, corneal reflex, and iris in determining the perceived direction of gaze. i-Perception, 9(4), Article 204166951876585. https://doi.org/10.1177/2041669518765852
6.
Arce-LoperaC.IgarashiT.NakaoK.OkajimaK. (2012). Effects of diffuse and specular reflections on the perceived age of facial skin. Optical Review, 19(3), 167–173. https://doi.org/10.1007/s10043-012-0028-4
7.
BalsdonT.CliffordC. W. G. (2018). How wide is the cone of direct gaze?Royal Society Open Science, 5(8), Article 180249. https://doi.org/10.1098/rsos.180249
8.
BoyaciH.DoerschnerK.MaloneyL. T. (2006). Cues to an equivalent lighting model. Journal of Vision, 6(2), 106–118. https://doi.org/10.1167/6.2.2
9.
BrainardD. H. (1997). The Psychophysics Toolbox. Spatial Vision, 10, 433–436.
CliffordC. W. G.PalmerC. J. (2018). Adaptation to the direction of others’ gaze: A review. Frontiers in Psychology, 9, Article 2165. https://doi.org/10.3389/fpsyg.2018.02165
12.
ErnstM.BanksM. (2002). Humans integrate visual and haptic information in a statistically optimal fashion. Nature, 415k, 429–433. https://doi.org/10.1038/415429a
13.
FarroniT.CsibraG.SimionF.JohnsonM. H. (2002). Eye contact detection in humans from birth. Proceedings of the National Academy of Sciences, 99(14), 9602–9605. https://doi.org/10.1073/pnas.152159999
14.
FarroniT.JohnsonM. H.CsibraG. (2004). Mechanisms of eye gaze perception during infancy. Journal of Cognitive Neuroscience, 16(8), 1320–1326. https://doi.org/10.1162/0898929042304787
15.
FaulF.ErdfelderE.LangA.-G.BuchnerA. (2007). G*Power 3: A flexible statistical power analysis program for the social, behavioral, and biomedical sciences. Behavior Research Methods, 39(2), 175–191. https://doi.org/10.3758/BF03193146
16.
FesharakiH.RezaeiL.FarrahiF.BanihashemT.JahanbakhshiA. (2012). Normal interpupillary distance values in an Iranian population. Journal of Ophthalmic and Vision Research, 7(3), 231–234.
17.
GamerM.HechtH. (2007). Are you looking at me? Measuring the cone of gaze. Journal of Experimental Psychology: Human Perception and Performance, 33(3), 705–715. https://doi.org/10.1037/0096-1523.33.3.705
18.
HansenD. W.JiQ. (2010). In the eye of the beholder: A survey of models for eyes and gaze. IEEE Transactions on Pattern Analysis and Machine Intelligence, 32(3), 478–500. https://doi.org/10.1109/TPAMI.2009.30
LinkeL.HorstmannG. (2024). New task—new results? How the gaze cone is influenced by the method of measurement. Attention, Perception & Psychophysics, 86(5), 1800–1815. https://doi.org/10.3758/s13414-024-02884-9
21.
MorgensternY.MurrayR. F.HarrisL. R. (2011). The human visual system’s assumption that light comes from above is weak. Proceedings of the National Academy of Sciences, 108(30), 12551–12553. https://doi.org/10.1073/pnas.1100794108
22.
OtsukaY.CliffordC. W. G. (2018). Influence of head orientation on perceived gaze direction and eye-region information. Journal of Vision, 18(12), Article 15. https://doi.org/10.1167/18.12.15
23.
OtsukaY.MareschalI.CalderA. J.CliffordC. W. G. (2014). Dual-route model of the effect of head orientation on perceived gaze direction. Journal of Experimental Psychology: Human Perception and Performance, 40(4), 1425–1439. https://doi.org/10.1037/a0036151
24.
OtsukaY.MareschalI.CliffordC. W. G. (2015). Gaze constancy in upright and inverted faces. Journal of Vision, 15(1), Article 21. https://doi.org/10.1167/15.1.21
25.
OtsukaY.MareschalI.CliffordC. W. G. (2016). Testing the dual-route model of perceived gaze direction: Linear combination of eye and head cues. Journal of Vision, 16(8), Article 8. https://doi.org/10.1167/16.8.8
26.
PalmerC. J.BrackenS. G.OtsukaY.CliffordC. W. G. (2022). Is there a ‘zone of eye contact’ within the borders of the face?Cognition, 220, Article 104981. https://doi.org/10.1016/j.cognition.2021.104981
27.
PalmerC. J.CliffordC. W. G. (2018). Adaptation to other people’s eye gaze reflects habituation of high-level perceptual representations. Cognition, 180, 82–90. https://doi.org/10.1016/j.cognition.2018.07.005
28.
PalmerC. J.CliffordC. W. G. (2020). Face pareidolia recruits mechanisms for detecting human social attention. Psychological Science, 31(8), 1001–1012. https://doi.org/10.1177/0956797620924814
29.
PalmerC. J.OtsukaY.CliffordC. W. G. (2020). A sparkle in the eye: Illumination cues and lightness constancy in the perception of eye contact. Cognition, 205, Article 104419. https://doi.org/10.1016/j.cognition.2020.104419
SchmidA. C.BarlaP.DoerschnerK. (2023). Material category of visual objects computed from specular image structure. Nature Human Behaviour, 7(7), 1152–1169. https://doi.org/10.1038/s41562-023-01601-0
32.
SenjuA.JohnsonM. H. (2009). The eye contact effect: Mechanisms and development. Trends in Cognitive Sciences, 13(3), 127–134. https://doi.org/10.1016/j.tics.2008.11.009
WestR. W. (2013). The effect of head turn and illumination on the perceived direction of gaze. Perception, 42(5), 495–507. https://doi.org/10.1068/p7343
35.
WollastonW. H. (1824). On the apparent direction of eyes in a portrait. Philosophical Transactions of the Royal Society of London, 114, 247–256. https://doi.org/10.1017/CBO9781107415324.004
36.
YangJ. N.MaloneyL. T. (2001). Illuminant cues in surface color perception: Tests of three candidate cues. Vision Research, 41(20), 2581–2600. https://doi.org/10.1016/s0042-6989(01)00143-2
