When do infants differentiate profile face from frontal face? A near‐infrared spectroscopic study

Abstract

The objective of the present study was to determine whether a developmental difference occurs in brain activity when infants look at frontal and profile views using near-infrared spectroscopy (NIRS), which is an optical imaging technique used to measure changes in the concentrations of oxyhemoglobin (oxy-Hb), deoxyhemoglobin (deoxy-Hb), and total hemoglobin (total-Hb). For this objective, we compared NIRS results in two age groups, 5- and 8-month-old infants, while they were looking at frontal views, profile views, and objects. We found that the concentration of oxy-Hb and total-Hb in the 5-month-old group increased for only frontal views in the right temporal regions. In contrast, the concentration of oxy-Hb and total-Hb in the 8-month-old group increased for both frontal and profile views in the right temporal regions. Therefore, the present study indicated that the right hemisphere was dominant for the perception of profile views as well as frontal views. In addition, the most important and interesting finding was that the infants' brain activity of the face area would become view-invariant at the age of 8 months but not at 5 months. The developmental period for view-invariant face recognition has been discussed in previous psychological studies, but this is the first objective study to confirm that the period is between 5- and 8-months by measuring the blood flow in the brain using NIRS.

Do infants recognize the Arcimboldo images as faces? Behavioral and near-infrared spectroscopic study

“…Jeffreys and Tukmachi (1992) and Rossion and Jacques (2008) showed that upright Arcimboldo images induce a similar pattern of brain activity as faces in adult observers. In the current study, using NIRS, we investigated whether infants show the same brain activity for faces as they do for facial photographs (Honda et al, 2010;Lloyd-Fox, Blasi, & Elwell, 2010;Nakato et al, 2009Nakato et al, , 2011Otsuka et al, 2007) during observation of upright and inverted Arcimboldo images.…”

Near-Infrared Spectroscopic Assessment of Haemodynamic Activation in the Cerebral Cortex - A Review in Developmental Psychology and Child Psychiatry

“…However, the oxy-haemoglobin and total-haemoglobin concentrations in 8-month-old infants increased for both frontal and profile views. These studies suggest that the right temporal hemisphere is specialised for face recognition in infants (Carlsson et al, 2008;Nakato et al, 2011;Nakato et al, 2009;Otsuka et al, 2007). Previous neuroimaging studies in adults also indicated that the right temporal cortex is involved in face recognition.…”

“…Haemodynamic changes during the face recognition process as assessed by NIRS have been documented in several studies (Blasi et al, 2007;Csibra et al, 2004;Grossmann et al, 2008;Honda et al, 2010;Ichikawa et al, 2010;Nakato et al, 2009Nakato et al, , 2011aNakato et al, , 2011bOtsuka et al, 2007). Newborns showed a spontaneous preference for face-like stimuli over non-face-like patterns (Fantz, 1961).…”

“…Numerous behavioural and electrophysiological studies have demonstrated that 5-7-month-old infants can visibly discriminate different facial expressions and exhibit an attention bias towards salient facial expressions (Leppanen & Nelson, 2009). Recent NIRS studies have demonstrated that infants show different haemodynamic responses to different facial stimuli (Nakato et al, 2009(Nakato et al, , 2011a(Nakato et al, , 2011b.…”

“…Moreover, infants have shown developmental changes in haemodynamic activity during the recognition of faces in frontal view and profile view (Nakato et al, 2009). The oxyhaemoglobin and total-haemoglobin concentrations in 5-month-old infants only increased for the frontal view in the right temporal regions.…”