Interactions between the perception of age and ethnicity in faces: an event-related potential study

Abstract

Face perception models propose that different facial attributes are processed by anatomically distinct neural pathways that partially overlap. Whether these attributes interact functionally is an open question. Our goal was to determine if there are interactions between age and ethnicity processing and, if so, at what temporal epoch these interactions are evident. We monitored event-related potentials on electroencephalography while subjects categorized faces by age or ethnicity in two conditions: a baseline in which the other of these two properties not being categorized was held constant and an interference condition in which it also varied, as modelled after the Garner interference paradigm. We found that, when participants were categorizing faces by age, variations in ethnicity increased the amplitude of the right face-selective N170 component. When subjects were categorizing faces by ethnicity, variations in age did not alter the N170. We concluded that there is an asymmetric pattern of influence between age and ethnicity on early face-specific stages of visual processing, which has parallels with behavioural evidence of asymmetric interactions between identity and expression processing of faces.

Keywords:

• face perception
• interference
• age
• ethnicity
• Garner

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1. To make sure that statistical effects were similar in both groups of 15 subjects (subjects in Group 1 participated in both the EEG and the behavioural experiments while subjects in Group 2 only participated in the behavioural experiment), the ANOVA analysis was also performed in each group separately. For reaction time, Group 1, showed no effect of section, F(1, 14) = 2.24, p = .16, condition, F(1, 14) = 1.22, p = .29, or interaction between the two, F(1, 14) = .003, p = 0.96. Likewise Group 2 showed no effect of section, F(1, 14) = 3.06, p = .1, condition, F(1, 14) = 0.009, p = .93, or interaction between the two, F(1, 14) = 0.27, p = .61. For accuracy, Group 1 showed no effect of section, F(1, 14) = 0.77, p = .39, condition, F(1, 14) = 0.04, p = .85, or interaction between the two, F(1, 14) = 2.5, p = .14, and Group 2 also showed no effect of section, F(1, 14) = 1, p = .33, condition, F(1, 14) = 2.69, p = .12, or interaction between the two, (F(1, 14) = 1.89, p = .19.

2. This would imply a simple feed-forward stage model, and may not be true of interactive models that incorporate feedback.

Additional information

Funding

This work was supported by the CIHR [grant MOP-106511]. Jason J. Barton was supported by a Canada Research Chair and the Marianne Koerner Chair in Brain Diseases. Ipek Oruç was supported by an NSERC Discovery grant [grant RGPIN 402654-11].