A hedge is a marker of uncertainty in language. Imagine the following situation: A parent questions a teenage child on a Sunday morning. He says, “What time did you come home last night?” The teenager might respond in a number of ways.

“I got home at midnight.”

“I got home at around midnight.”

“I got home at midnight, I think.”

“I got home at, like, midnight.”

The first answer has no hedge in it. The next two sentences use the hedges ‘around’ and ‘I think.’ Both of these hedges are a way of saying that the answer is approximate and that it may not be exactly correct. The last answer uses the word ‘like.’ It is less clear what the word ‘like’ is doing in this sentence. It might be a hedge as well, though it might just be a way of emphasizing what is being said.

Do these hedges matter?

This question was explored by Kris Liu and Jean E. Fox Tree in a paper in the October, 2012 issue of Psychonomic Bulletin and Review. These researchers suggested that hedges might call to the information that they mark, and so that information might be well-remembered by listeners. At the same time, hedges might mark information as unreliable, and so the information might not be retold by listeners later.

In one study, Liu and Fox Tree looked at whether information would be retold by listeners. In this study, two participants came to the lab. At the start of the study, one participant was asked to tell a story (for example, a story about a large purchase they had made recently). After telling this story, both the teller and the listener were brought into separate rooms and were asked to retell the story. Then, the pair did this again, only now the listener from the first part of the study told a story.

The researchers were particularly interested in people’s memories for numbers that were used in the original story. Would these quantities be put in the story when it was retold?

When people used a quantity in the story without a hedge (“The shirt cost $15.”) it was quite likely to be used in a retelling of the story both by the original speaker and by the listener. Quantities with a ‘like’ (“The shirt cost, like, $15.”) were also used in retellings. Quantities that were hedged (“The shirt cost around $15.”) were not included in retellings of the story.

So far, that makes sense. When you use a hedge, it marks the information as unreliable, so you would expect that it would not be included as a detail when retelling a story.

In a second study, one of the stories told by a participant in the first study was played for a new group of participants. The story had many quantities in it. Some of them involved hedges and some involved ‘likes.’ In some versions of the story, the hedges were removed from the recording. In other versions the ‘likes’ were removed. After people heard the story, they were asked specific questions about the story that involved the quantities (“How much did the shirt cost?”)

When the quantity had a “like” with it, it was equally well remembered, regardless of whether the “like” was present in the recording. Interestingly, when the quantity had a hedge with it, it was actually better remembered when the hedge was there than when it was not. That means that the hedge caused the information to be better remembered, even though that information was not used later in a retelling of the story.

Why would this happen?

Hedges cause people to think more about the information that is hedged. In order to understand what the hedge is doing, you have to work a little harder to figure out why the speaker would want to qualify what they are saying. The more work you put into something, the more likely you are to remember it later.

However, once you understand the hedge, you realize that it is telling you that the quantity is just approximate. So, you may remember that quantity better, but you also realize that you do not need to treat it as an exact number. As a result, you may not pass it along to other people.

Finally, the word ‘like’ does not seem to work the same way as other hedges. One reason for that is that ‘like’ has become a crutch that many people use when they are speaking. They fill lots of space in their speech with the word ‘like.’ As a result, it may not have any specific meaning for listeners.

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