Carryover of scanning behaviour affects upright face recognition differently to inverted face recognition

ABSTRACT

Face perception is characterized by a distinct scanpath. While eye movements are considered functional, there has not been direct evidence that disrupting this scanpath affects face recognition performance. The present experiment investigated the influence of an irrelevant letter-search task (with letter strings arranged horizontally, vertically, or randomly) on the subsequent scanning strategies in processing upright and inverted famous faces. Participants’ response time to identify the face and the direction of their eye movements were recorded. The orientation of the letter search influenced saccadic direction when viewing the face images, such that a direct carryover-effect was observed. Following a vertically oriented letter-search task, the recognition of famous faces was slower and less accurate for upright faces, and faster for inverted faces. These results extend the carryover findings of Thompson and Crundall into a novel domain. Crucially they also indicate that upright and inverted faces are better processed by different eye movements, highlighting the importance of scanpaths in face recognition.

KEYWORDS:

• Eye movements
• carryover
• face perception
• face inversion effect
• scanpaths

Acknowledgements

The authors would like to thanks Dr Andrew Meso for assistance in the eye-tracking data analysis. The authors would like to thank three anonymous reviewers for helpful comments on a previous version of this manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Peter J Hills http://orcid.org/0000-0002-0097-9170

Notes

1. The random letter string is likely to produce an equal number of vertical and horizontal eye movements, whereas the vertical and horizontal letter strings should engage typical reading patterns (i.e., from left to right and then downwards).

2. While pressing “space” as the method for recording identification is not the most ideal method as it increases error, there is no reason to think that the error would occur in one condition more than another.

Additional information

Funding

This research was funded by an Undergraduate Summer Research Bursary from The Nuffield Foundation awarded to Mila Mileva, supervised by Dr Peter J Hills.