Babies as early as six months can understand basic words (whether signed or spoken), much earlier than previously thought or believed.
The other day as I was out for grocery shopping without her once, I informed Juli where I was going. Juli (age 0;4,2) cried "maaa maaaa".
Recently, taking Juli to the grocery store, I introduced the ASL words food store. She, sitting in the shopping cart, smiled and turned her head to look around.
Before I headed out the door that week, I informed Juli, glossed as Mother ix-me go-out, drive-to food store. I repeated a few times and also added, ix-me come-here home will will will.
Juli smiled and busily looked around. I left, shopped, and checked my cellphone for a new message. I felt tempted to text her father and asked how it was. Nope, I came back home and found Juli in happy state. We greeted.
In the past weeks, I observed Juli's responses at the end of my utterances. Sometimes Juli looked at me with pondering eyebrows. Sometimes, she kicked and waved excitedly. Sometimes she smiled at the end of my utterances.
Juli (age 0;5) frowned a little bit as I put her in the reversible (parent-face or rear-facing) stroller. I uttered wanna go outside, walk, icl-stroller. Juli smiled excitedly and her eyes brightened.
We were silent as Juli watched different things in the surroundings. At the near end of the long walk, Juli watched me as I walked. I took this sign as her invitation to talk.
I uttered outside warm, not cold. I had used cold more often before. Juli probably knew what it meant more than warm and she probably knew the meaning of not and/or nothing/none. So, I added the opposite not cold.
I noticed that Juli (age 0;6) understood some ASL words through her gaze pointing toward correct objects or symbols. Researching to find information on this, I came across latest research studies that can verify that baby indeed can understand from 6 months.
Understanding through behavior
For example, one day Juli and I sat together in front of each other, eating apple slices. She ate her apple pieces through the mesh feeder while I ate mine with caramel dips.
Juli appeared to imitate me by dipping her mesh feeder in the plate repeatedly until my apple slices ran out. (see an example in 2nd video below).
Juli dropped her mesh feeder behind herself every time I signed done/finished.
When the apple slices and the caramel dip were empty, I explained (translated as) "Done, we were done eating apple". She then dropped her mesh feeder. I picked up and signed "more".
Juli resumed eating for a bit while. Then I informed her that we were done. She eventually dropped her feeder again.
Research indicates that infants as young as 6 months can understand the meaning of many spoken words. They at this age don't say nor point, but actually they put together the things in the world along with the words. [Ref]
Understanding through gaze pointing
A month later (m8w1), Juli demonstrated ASL receptive skill and understanding. For example, sitting near the jumper under the sofa, I asked Juli if she wanted to jump, want jump?. Juli's gaze turned to the jumper under the sofa. I noticed the first time and observed this again the next times. Same results.
Gazing is an advantage that helped me recognize Juli's comprehension, when word or finger-pointing didn't emerge yet. Baby does not finger point until around 9-12 months other than reaching and grasping.
Even Elliott the Cat understands or at least it seems.
Juli's furry friend Elliott the housecat had never met a baby before. The first time the cat met Juli, she trusted her with all her heart.
But, as Juli grew and grasped things. Elliott took a precaution. Once Juli grasped Elliott's tail and furry skin, Elliott maintained a cautious distance.
Juli walked with my support toward the sitting cat. Elliott took a step above on the stairs. Her animal instinct took over. As Juli grabbed high, Elliott snapped with her paw near Juli's hand as if to give a warning.
I picked up Juli. I gently looked into Elliott's eyes and talked to him in ASL, #nono, you-know ix[baby] just baby (translated as), "No, no. You know, she's just a baby."
From there on, Elliott joined us comfortably, lying down right next to Juli even when Juli touched him. Elliott was aware that I made sure that Elliott wouldn't get hurt.
It's not like Elliott understood ASL words. But, he appeared to understood the tones, moods, and the contexts surrounding words.
Babies may connect words to their referents by gazing long before they can express by finger-pointing or uttering a word.
For example, Juli turned her gaze toward a referent when I signed the ASL word. Likewise, Grandma Z reported that Juli turned to gaze toward the door or window door when Z told Juli, (translated as) "Mom will be coming home soon."
In an activity, I introduced three written English words to Juli (age 8;4) by writing on the little whiteboard: dog, baby, and mama and articulated them in ASL that Juli were familiar with.
Through several rounds, the patterns were similar in which Juli was kind of indifferent to the signed words #dog along with tapping on the lap and baby. But, Juli became excited every time the ASL word mother came up.
When the ASL word mother came up, Juli looked at the art images (one of those was the image of me) in one direction and also she turned around to look at the photographs of me in the other direction.
In the video, Juli also responded to "dog" by tapping on my lap twice throughout the video.
The video clip from last week shows that Juli appeared to learn the relationship between the ASL word #dog or the older sign (a hand tapping on the leg) and the picture of the dogs.
In the last part of the video clip, I asked Juli ix what? (English translation: What is this?). Juli responded by tapping on my leg.
Note: Grandma Z reported that earlier she taught Juli the ASL word "dog" and tapped on her leg. Juli tapped on her leg also.
Then when Z pointed at the cat in the picture book, Juli tapped on her lap. Perhaps, they look alike or perhaps Juli overcategorized them. Or perhaps she found the closest association she could express.
This week Juli and I took a stroller walk on the sidewalk. The cat sat on the porch. I stopped and pointed to the cat. Juli turned and looked. She patted on her lap.
Earlier Grandma Z reported that Juli patted on her lap when grandma showed her the picture of a dog in the picture book. The same result with another image of the dog.
But then, as Z pointed at the image of the cat. Juli patted on her thigh. It showed that Juli might overgeneralize dogs and cats together -- furry friends with pointed ears and tails.
This documentation project follows a baby's language acquisition, literacy development, and phonological acquisition in sign language, specifically ASL, week by week from gazing at birth to manual babbling, to first words just before the first birthday in a natural native-ASL environment and visual culture.
The second-year documentation continues to follow the same one-year-old child's language and phonological acquisition and literacy development in ASL on a weekly basis from the one-word stage to two-word and multiple utterances.
The third year documentation continues to follow the same child's ASL language and literacy development on a regular basis from age two to three. It surveys ASL phonological acquisition and more complex utterances.
The fourth year documentation continues to follow the same child's ASL language and literacy development on a regular basis from age three to four. It surveys ASL phonological acquisition and more complex utterances.
This five-year documentation and project follows the bilingual child's natural language acquisition in sign language from newborn to age five.