Table 1.

Operational definitions of the seven coordinated attention bout types.

Coordinated Attention Types	Definition
Mutual Gaze	Simultaneous fixations of infant and parent face ROIs.
Parent:Face/Infant:Object	Simultaneous fixations of parent looking at infant’s face and infant looking at any object ROI.
Parent:Object/Infant:Face	Simultaneous fixations of infant looking at parent’s face and parent looking at any object ROI.
Parent:Triadic/Infant:Triadic	Only continuous alignment towards the same object ROI that also included looks to the face ROI from both parent and infant for less than 5s.
Parent:Triadic/Infant:Object	Only continuous alignment towards the same object ROI that also included looks to the face ROI from parent for less than 5s.
Parent:Object/Infant:Triadic	Only continuous alignment towards the same object ROI that also included looks to the face ROI from infant for less than 5s.
Parent:Object/Infant:Object	Only continuous alignment towards the same object ROI that did not include any face looks from either parent or infant.