Is the Illusion-of-Truth Effect Affecting Our Decision-Making?

[Math Is Hard]

I came across something interesting when I was doing some reading about implicit memory for a project.

The illusion-of-truth effect states that a person is more likely to believe a familiar statement than a new one. In a 1977 study, testers read subjects 60 plausible sentences every two weeks and asked them to rate the validity of the sentence. Unbeknownst to the subjects, the testers strategically repeated a few of these sentences, both true ones and false ones, from session to session. The results showed that the subjects were more likely to rate as true the sentences that they had previously heard. As priming, the illusion-of-truth effect occurred just as much for sentences that the subjects had no conscious recollection of having previously heard (Hasher, Goldstein, & Toppino, 1977). Because this illusion-of-truth effect occurs even without explicit knowledge, it is a direct result of implicit memory. Amazingly, subjects tend to rate these previously heard sentences as more true even when the person initially giving the sentences states that they are false (Begg, Anas, & Farinacci, 1992). The illusion-of-truth effect in some ways shows the dangers of implicit memory because it can lead to individuals’ making decisions on a statement’s veracity without conscious knowledge of why they act.

There was an article I found which focused on how this effect could be a big problem with the elderly. Apparently, repeated warnings that a claim is false can sometimes only serve to make that thing seem "familiar" causing a sense of trust in the exact thing that should be avoided!

http://www.acrwebsite.org/topic.asp?artid=250

Something to think about when you are reminding great-grandpa that those magnetic bracelets aren't going to help his rheumatism.

 

[Ivan Seeking]

Heh, Rove figured this one out long ago. If you say something often enough, it becomes truth.

 

[wuliheron]

In my mind, this is just another way of saying accent the positive rather than dwelling on the negative.

 

[zoobyshoe]

Thanks for posting that, Math. The notion that we are likely to rate what is familiar as also being true is an important one to ponder.

 

[zoobyshoe]

I came across something interesting when I was doing some reading about implicit memory for a project.

I had to google the term "implicit memory". The Wikipedia equates it with "procedural memory". I had heard the latter term, but not the former.

Anyway, what was the project?

 

[Moonbear]

I think I've heard about that before...it must be true.

With regard to the familiarity issue in older adults, I wonder if the way you phrase something would make a difference there. In the example given in the article, they were saying, "It's not true that..." and then saying a complete statement. Maybe having the statement intact like that makes it easier to forget the "It's not true that..." part that preceded it. Perhaps you need to state the truth differently. To use the example given of shark cartilage, maybe you need to say something like, "Shark cartilage does not improve arthritis." Or, perhaps distance it even more from the misleading claim to be, "Shark cartilage is a product of snake oil salesmen." Turn it so the familiarity isn't linking it to the false claim but to a clearly different claim.

 

[zoobyshoe]

I think I've heard about that before...it must be true.

With regard to the familiarity issue in older adults, I wonder if the way you phrase something would make a difference there. In the example given in the article, they were saying, "It's not true that..." and then saying a complete statement. Maybe having the statement intact like that makes it easier to forget the "It's not true that..." part that preceded it. Perhaps you need to state the truth differently. To use the example given of shark cartilage, maybe you need to say something like, "Shark cartilage does not improve arthritis." Or, perhaps distance it even more from the misleading claim to be, "Shark cartilage is a product of snake oil salesmen." Turn it so the familiarity isn't linking it to the false claim but to a clearly different claim.

I think you're probably right. "Shark cartilage is the product of snake oil salesmen." is a clear, direct statement, rather than a negation of a statement.

 

[Math Is Hard]

I had to google the term "implicit memory". The Wikipedia equates it with "procedural memory". I had heard the latter term, but not the former.

Anyway, what was the project?

I believe that implicit memory includes the subsets of procedural memory and also priming. Both tend to work as automatic, effortless processes.

I was studying up a little on serial vs. parallel processes in visual search for a research project we've been trying to design for a class. Some searches appear to operate as a parallel process in that things just "pop out" at us from a group of items (an automatic process), and I was looking for relationships to automatic processes in memory systems.

 

[Math Is Hard]

I'm not sure that "shark cartilage = bad" is remembered any better than "shark cartilage = good" only that the familiarity of "shark cartilage" persists outside of any context. And I think it's that familiarity that causes the trouble.

 

[zoobyshoe]

I'm not sure that "shark cartilage = bad" is remembered any better than "shark cartilage = good" only that the familiarity of "shark cartilage" persists outside of any context. And I think it's that familiarity that causes the trouble.

Hmmmm. I don't think the article is saying this. I think it is saying that, if the first thing you have in your mind is "shark cartiledge=bad" it will be remembered specifically as bad. You may know that for a very long time people avoided eating tomatos since they had acquired the reputation of being poisonous. Likewise, the first thing most people learn is "wild mushrooms=bad" and it is hard to get them to eat a benign variety of wild mushroom. The problem with shark cartilage doesn't seem to be that it persist without context, but that it persists in memory in the first context in which its brought to people's attention: "shark cartilage=good". The first impression lingers as the most familiar.

 

[Math Is Hard]

I am not seeing what you are seeing in that article. By context, I don't think they are talking about a thing being labelled "good" or "bad" but rather when/where/from whom the information was learned.

 

[zoobyshoe]

I am not seeing what you are seeing in that article. By context, I don't think they are talking about a thing being labelled "good" or "bad" but rather when/where/from whom the information was learned.

OK. I think we're both off the mark. It is not the first thing we hear that makes a difference, as I said, and it's not unvalenced subject matter as you said.

"In this research, older adults (age range: 71-86) and younger adults (age range: 18-25) read statements about health and medicine (for example, “Aspirin is bad for tooth enamel,” or “DHEA supplements may lead to liver damage”)."

In all cases the remembered statement has to qualify a thing as good or bad. The decision about whether we think the statement is true or false rests in how familiar it seems. "Shark cartilage", by itself, doesn't require a true or false decision. "Shark cartilege is good for arthritis" requires assessment as true or false. If it seems familiar, we suppose it's true. If it doesn't we're more skeptical.

 

[Math Is Hard]

I conclude from this research that we should avoid getting old.

 

[zoobyshoe]

I conclude from this research that we should avoid getting old.

What? I always avoid getting colds.