At about four months, baby's color vision matures as well as the other visual abilities such as depth perception and distance. With that, eye-hand coordination is developing more.
Then baby pays attention to details at about 5 months.
Typically native signers fixate their gaze on the signer's face, not hands, in receptive signing. They have larger perceptual span and peripheral vision. However, when it comes to fingerspelling, generally they shift their gaze away from the face.
Similarly, Juli in the video clip shows her gaze shifting between my face and fingerspelling hand.
How much perceptual span do infants in a native signlan environemnt have? How swift can they shift their gaze between the face and one-handed fingerspelling? I hope to see some findings in future research studies.
Not only Juli shifted her gaze toward my hand when fingerspelling, she also looked at my hand when producing manual numeral.
During reading the book "Counting Kisses" by Karen Katz, Juli shifted her gaze toward my hand as I counted the numbers from one to four.
I found it to be one of Juli's favorite stories. Because, it's interactive. Not only Juli watched the numbers I spelled, she also enjoyed the kisses. Think about learning rewards.
Four month old baby (m5w3) Juli sat on my lap in front of the closet mirror. She looked at herself and me in the mirror. She smiled at herself and smiled a lot more at her reflected mother than myself.
In addition to the closet mirror, I held a hand mirror in front of Juli. She looked at me in the handheld mirror and I made eye contact with her in the handheld mirror.
Juli then shifted her gaze at me in the closet mirror. Again I looked at her. She gazed back at the handheld mirror and made eye contact with me. We continued doing the gaze turn-taking between the handheld and the closet mirror.
Eye contact and gaze shifting are important skills in sign language development.
Baby's eyes begin to move better as a team at around 3 months of age. She/he also is able to follow moving objects and shift his gaze from one thing to another without moving his head.
By 6 months, the baby would be able to move her/his eyes faster and accurately follow objects. Juli did demonstrate this at 5 months old as described below.
One evening at grandparents' for dinner, Juli observed from the end of the table surrounded by native ASL-speaking extended family members having conversations in ASL.
Suddenly, everyone around the table conversed turn-taking quickly. I noticed something about Juli's darting gaze.
Her eyes quickly and accurately followed turn-taking conversation from one to another. How did Juli know when the next person was turn-taking? There was no object moving from one point to another point. How?
Juli's ability to follow the next person signing quickly tells about her developed sharpness of peripheral vision.
At age 0;6, Juli darted her eyes between face, hand, and the object.