So can we ever really know whether Neil Armstrong uttered that little “a”?

Perhaps not. But in a recent study, my colleagues and I tried to get to the bottom of this.

First, we explored how similar the speech signals are when a speaker intends to say “for” or “for a.” That is, could a production of “for” be consistent with the sound waves, or acoustics, of “for a,” and vice-versa?

So we examined nearly 200 productions of “for” and 200 productions of “for a.” We found that the acoustics of the productions of each of these tokens were nearly identical. In other words, the sound waves produced by “He bought it for a school” and “He bought one for school” are strikingly similar.

But this doesn’t tell us what Armstrong actually said on that July day in 1969. So we wanted to see if listeners sometimes miss little words like “a” in contexts like Armstrong’s phrase.

We wondered whether “a” was always perceived by listeners, even when it was clearly produced. And we found that, in several studies, listeners often misheard short words, like “a.” This is especially true when the speaking rate was as slow as Armstrong’s.

In addition, we were able to manipulate whether or not people heard these short words just by altering the rate of speech. So perhaps this was a perfect storm of conditions for listeners to misperceive the intended meaning of this famous quote.

The case of the missing “a” is one example of the challenges in producing and understanding speech. Nonetheless, we typically perceive and produce speech quickly, easily, and without conscious effort.

A better understanding of this process can be especially useful when trying to help people with speech or hearing impairments. And it allows researchers to better understand how these skills are learned by adults trying to acquire a new language, which can, in turn, help language learners develop more efficient strategies.

Fifty years ago, humanity was changed when Neil Armstrong took those first steps on the Moon. But he probably didn’t realize that his famous first words could also help us better understand how humans communicate.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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