In the last unit, we suggested that intensions for word meanings might be organized in our minds in fuzzy categories. Our minds construct categories of things based on our experience in the world: each time we encounter an extension of a word, we count it as an exemplar in that fuzzy category. There is some evidence from psychology and psycholinguistics that our mind really does represent a difference between prototypical category members and peripheral members. For lots of categories, we have some instincts about what kinds of exemplars are prototypical and what kinds are peripheral. When we give somebody the name of a category and ask them to name an exemplar, people from a given language community are remarkably alike in the first things they name as exemplars. If your mental grammar for English is like mine, then perhaps your prototypical bird is a robin, your prototypical fruit is an apple, and your prototypical tool is a hammer.
In a behavioural study of word recognition, participants saw a word appear on a screen and had to say the word out loud. This is called a rapid naming task. Some of the words referred to prototypical exemplars of their particular category and some of them referred to peripheral exemplars. The prototypical and peripheral exemplars were all mixed up in the experiment, but when the researchers measured how fast people had been able to name the word that they saw, the found that people were faster to name the prototypes than the peripheral exemplars.
The same researchers used these words in a lexical decision task. In this kind of task, a word appears briefly on a screen, and the person’s job is just to decide whether it’s a word or not, and say Yes or No. So if the word pants appears on the screen, you would say “Yes”, because it’s a real word in English. But if pfonc appears, you say “no”, because that’s not a word of English. What the researchers found in the lexical decision experiment was, again, that people are fast to make a decision about a word if it refers to a prototypical category member, and slower to make the decision if the word refers to a peripheral member.
These findings indicate that the process of recognizing a word is easier and faster if that word refers to a prototype. We can interpret these findings to mean that our intensions for categories are made up of exemplars and that prototypical exemplars have a privileged position in our intensions.
So that’s a couple of examples of psycholinguistic tasks we can use to observe how words are processed in our minds: a simple naming task, and a lexical decision task. There’s an additional task that we can combine with each of these, to allow us to investigate relationships between different words. That task is called priming. A primed lexical decision task works like this: First, a word appears on the screen for a very short length of time: that word is called the prime. The prime disappears, and then a second word appears on the screen. This word is the target, and the participant makes a lexical decision about the target. The prime word can have an influence on how quickly people make their lexical decision about the target word.
For example, in one condition, the prime might be doctor and the target nurse. In another condition, the prime could be apple and the target nurse. As you might expect, people are faster to make their lexical decision to nurse when it’s primed by doctor than when it’s primed by apple. When we observe this faster lexical decision, we interpret that to mean that these two words are connected to each other in our minds.
Over the years, psychologists and psycholinguists have conducted thousands of experiments on priming, and the results of these experiments show us how words are related to each other in our minds. The scientific literature has shown priming between words that are members of the same category, for words that are synonyms, antonyms, and even for words that describe things that share attributes. For example, an orange and a baseball aren’t members of the same category, but they’re both spheres, so they can prime each other.
Looking at all these and many other priming effects, we can conclude that those semantic relationships play an important role in how the meanings of a word are organized in our minds.