Cortical networks for face perception in two-month-old infants

Area of Science:

• Neuroscience
• Developmental Psychology
• Visual Processing

Background:

• Newborns exhibit an innate preference for upright human faces.
• This face preference behavior temporarily disappears around one month of age before reappearing later.
• The neural mechanisms behind this U-shaped developmental pattern are not fully understood.

Purpose of the Study:

• To investigate the functional development of the cortical visual pathway for face processing in infants.
• To elucidate the neural underpinnings of the U-shaped trajectory in infant face preference.
• To differentiate the roles of subcortical and cortical visual pathways in early face recognition.

Main Methods:

• Utilized S-cone-isolating stimulation to selectively target the cortical visual pathway, effectively blinding the subcortical pathway.
• Employed luminance stimuli, which engage both subcortical and cortical visual pathways.
• Observed infant face preference behavior at two, four, and six months of age using these distinct visual stimuli.

Main Results:

• Infants showed no preference for upright faces with luminance stimuli at two months but did at four and six months, indicating the recovery phase.
• Infants demonstrated a preference for upright faces with S-cone stimuli even at two months, suggesting early cortical pathway function.
• This indicates the cortical visual pathway for face processing is functional at the U-shape's lowest point (two months).

Conclusions:

• The temporary decline in face preference is likely due to a conflict between developing subcortical and cortical visual pathways.
• The subsequent recovery and reappearance of face preference involve the establishment of coordinated activity between these two pathways.
• This study clarifies the developmental trajectory of face processing, highlighting the interplay between different visual systems in early infancy.