Table 3.

Gestural Function Categories

Function Category	Gestural Function	Definition
Non-communicative	Non-social act	Any non-utilitarian act, not conveying communicative intent (e.g., rhythmic hand banging, body rocking)
Communicative	Request object	Show desire to obtain something
	Accept	Receive something offered
	Social playful	Engage in interactive game, usually involving an object (e.g., playing catch)
	Offer	Present something to someone to accept/reject
	Request up	Show desire to be held or picked up
	Designate	Indicate person or object of interest
	Exult	Show happiness or excitement, celebrate
	Bye-bye	Wave “bye-bye”
	Refuse	Indicate unwillingness to do something
	Show	Make something visible to be perceived by another
	Seek attention	Show desire to engage with another
	Assent	Express approval or agreement

Note. All Non-social actions from Table 2 Were treated as expressing Non-communicative functions. Universal Social and Conventional actions were categorized as expressing one of the Communicative functions. Depending on the apparent intent of the infant, Reach could be categorized as expressing Request Object, Offer, or Accept. As in Table 2, the Communicative function list is not complete, but includes all the gestural functions actually observed.