Abstract
How do eye movements influence recognition memory for faces? Henderson et al. (2004) recently found that younger observers performed better when they studied faces under free-view conditions (in which no restrictions were placed on eye movements) and then tested under free-view conditions, compared to when observers studied faces under fixed-view conditions (in which fixations were restricted to a small central area of the face) and then tested under free-view conditions. Henderson et al. concluded that eye movements are functional: they help to encode faces in a way that facilitates subsequent recognition. However, it is possible that free-viewing during study lead to better recognition simply because the same mode of viewing was used in the test phase. The current experiment examined this idea in younger (age = 19) and older (age = 70) subjects. Viewing conditions (fixed and free) were combined factorially with the phase of the experiment (study and test), yielding four conditions. In the study phase, 24 faces were each presented for 10 secs, and subjects were instructed to remember the faces. In the test phase, 48 faces were each presented until observers responded whether a face was previously studied (50%) or novel (50%). 12 older and 12 younger subjects were tested in each condition. There was a main effect of condition: recognition (d') was significantly better in the two conditions that allowed free viewing during the study phase (F(1, 40)=8.01, p=0.007), irrespective of the type of viewing in the test phase. The main effect of age and the age x condition were not significant. Our findings support Henderson et al.'s claim that eye movements during study improve later recognition, and further show that this functionality persists with aging.
Donna Waxman for assistance with subjects and setup, Jesse Husk for help with statistical analysis and critical review and Sarah Creighton for assistance in running subjects and theoretical advice.