Several weeks ago, we checked out a book from the library that T LOVES (“Mr. Brown Can Moo, Can You?” by Dr. Seuss) – he loved it so much that we actually ended up renewing it several times in a row! Anyway, there’s a part in the story that we read in a whispered voice, but, whenever I whispered, I thought T’s reaction was sort of interesting – it sort of seemed to me like he wasn’t really recognizing the whispered speech as speech. It seemed like even though he was hearing it, he maybe didn’t understand that the whispers included words just like in “normal” voiced speech.
A lot of studies (like this one) have shown that adults have more trouble understanding whispered speech compared to normal speech. This makes sense, since whispered speech lacks a lot of the frequency information in normal speech. Since babies and children require a lot of time and experience to reach adult-like levels in their language skills, I thought that babies might lack the ability to understand whispered speech – I wondered if T (10.5 months) is able to recognize whispered speech at all. So, we did a little experiment!
When researchers test adults to see how well they can understand different types of speech or speech in different types of noise, they play words or sentences and ask the research subjects to repeat back what they hear. T obviously can’t do that! So, I recorded myself saying 4 different names – T’s name and 3 other names – in a normal voice and in a whisper. I then randomly played these names to see whether T was more likely to look up when he heard his own name compared to the other names. Since T knows his own name, if he looked up more for his own name compared to the other names, that might be an indication that he was understanding what he heard.
We had a bit of trouble conducting our experiment. T was very interested in participating, but wanted to take a more active role than that of research subject, and he was particularly keen to tweak the software running the experiment from my laptop. My husband (G) ended up distracting T with toys while I played different names and recorded whether or not he looked up when he heard them. (This is totally not how this experiment would be conducted in a real lab!). We also didn’t get as many trials as we wanted, since T quickly tired of his mom sitting on the couch staring at him.
With that being said, here are the results! The graph below shows the proportion of times T noticed when I played his name compared to the 3 other names for normal (voiced) speech on the left and whispered speech on the right. For the normal speech, T looked up every time (it was cute – he tended to have a bit of a delayed reaction and would look up surprised but happy someone had called him), and only about 1/3 of the time for the other names. For the whispered speech, T was much less consistent, and in fact, he often didn’t look up at all, for any of the names, but would sometimes just pause in what he was doing rather than looking up.
Since T looked up every single time when he heard his name said normally and hardly at all for the other names, I’m pretty confident T recognizes his name!
Although these results seem to suggest that T has more trouble understanding whispered speech than normal speech (since he didn’t react much to hearing his name when whispered), I’m not confident of that. Although T seemed to barely noticed the whispered speech during our experiment, G and I spent a lot of the weekend whispering T’s name to see if he looked up, and it seemed like he did. It might be that during our experiment, T was too distracted, or maybe, had grown tired of looking up when hearing his name just to see me staring at him and marking stuff down.
This is my second little experiment with T with inconclusive results (here’s the first) – babies are difficult to get good data from!