Kim Craig '08 (Wilbraham, Mass.), Miranda Raimondi '08 (Rome, Italy) and Danica Wuelfing '10 (Sarasota, Fla.) studied inhibition and negative priming this summer with Associate Professor of Psychology Penny Yee.
Participants in their study were asked to memorize word pairs containing a stimulus word and a response word. Every time a participant saw the stimulus word, he or she would have to say the response word out loud, thus inhibiting the stimulus word. For example, in the word pair car/plane, participants would have to say "plane" whenever they saw "car." Since the word car is ignored in favor of the word plane, this word pair inhibits "car." Sometimes, one word pair would contain a response word that was previously inhibited by another word pair. For instance, participants may have been given the word pairs car/plane (i.e. say "plane" in response to "car") and lime/car (i.e. say "car" in response to "lime"). In this case, the first word pair inhibits the response word of the second word pair.
By recording how long it takes participants to say the response words when confronted with their corresponding stimulus words, the group hopes to test two hypotheses. First, they want to see if there is a delay in responding to a stimulus word when its response word had been previously inhibited by another word pair. This delay in reaction time is referred to as negative priming. Second, they are trying to determine if semantic similarity increases negative priming.
Suppose, for example, that three different participants (A, B, and C) were each given two word pairs to memorize (stimulus words are bolded and response words are italicized):
Let's say the participants were all shown the word mind, the stimulus word for each one of the second word pairs. Craig, Raimondi and Wuelfing believe that participant B would be able to respond faster than either participant A or C because, unlike the other two participants, his response word (truck) was not negatively primed by the first word pair. Furthermore, they theorize that participant C would respond faster than participant A because his response word (car) was inhibited by a word that is semantically different (i.e. a car is machine used for transportation while a lime is a type of fruit). Participant A's response word (car), however, was inhibited by a word that is semantically similar (i.e. both cars and planes are modes of transportation), and, as a result, the inhibition and reaction time are increased.
The group says no one else has conducted this type of experiment before and hopes that their study will help them to better understand what happens when a person ignores a stimulus and how this ability to ignore stimuli relates to semantics. By answering these questions, they would like to gain new insight into human memory processes. Raimondi likened the memory processes her group is studying to those that occur when American tourists travel to Europe. When Americans cross the street in the U.S., they automatically look to the left first because that is the direction of oncoming traffic. In Europe, however, they must change this automatic response because traffic is now coming from the opposite direction.
This is the first summer of research for all three members of the group. They originally became interested in this project after taking psychology courses during the school year. After taking Memory and Cognition, a psychology course taught by Yee, Craig and Raimondi wanted to learn more about memory. Wuelfing took Introduction to Psychology, another course that was taught by Yee. Although she admits she had "no idea what [her] research project was going to involve" when she signed up for research, Wuelfing said she really liked Yee and wanted to work with her over the summer.
Craig, a psychology major and history minor, sings in the choir. Raimondi, a neuroscience major and art minor, is an orientation leader and has participated in the urban service experience and Guatemala project. Wuelfing, a high jumper on the track team, is thinking about a possible math major.
-- by Nick Berry '09
Participants in their study were asked to memorize word pairs containing a stimulus word and a response word. Every time a participant saw the stimulus word, he or she would have to say the response word out loud, thus inhibiting the stimulus word. For example, in the word pair car/plane, participants would have to say "plane" whenever they saw "car." Since the word car is ignored in favor of the word plane, this word pair inhibits "car." Sometimes, one word pair would contain a response word that was previously inhibited by another word pair. For instance, participants may have been given the word pairs car/plane (i.e. say "plane" in response to "car") and lime/car (i.e. say "car" in response to "lime"). In this case, the first word pair inhibits the response word of the second word pair.
By recording how long it takes participants to say the response words when confronted with their corresponding stimulus words, the group hopes to test two hypotheses. First, they want to see if there is a delay in responding to a stimulus word when its response word had been previously inhibited by another word pair. This delay in reaction time is referred to as negative priming. Second, they are trying to determine if semantic similarity increases negative priming.
Suppose, for example, that three different participants (A, B, and C) were each given two word pairs to memorize (stimulus words are bolded and response words are italicized):
| Participant | Word Pair #1 | Word Pair #2 |
| A | Car / plane | Mind / car |
| B | Car / plane | Mind / truck |
| C | Car / lime | Mind / car |
Let's say the participants were all shown the word mind, the stimulus word for each one of the second word pairs. Craig, Raimondi and Wuelfing believe that participant B would be able to respond faster than either participant A or C because, unlike the other two participants, his response word (truck) was not negatively primed by the first word pair. Furthermore, they theorize that participant C would respond faster than participant A because his response word (car) was inhibited by a word that is semantically different (i.e. a car is machine used for transportation while a lime is a type of fruit). Participant A's response word (car), however, was inhibited by a word that is semantically similar (i.e. both cars and planes are modes of transportation), and, as a result, the inhibition and reaction time are increased.
The group says no one else has conducted this type of experiment before and hopes that their study will help them to better understand what happens when a person ignores a stimulus and how this ability to ignore stimuli relates to semantics. By answering these questions, they would like to gain new insight into human memory processes. Raimondi likened the memory processes her group is studying to those that occur when American tourists travel to Europe. When Americans cross the street in the U.S., they automatically look to the left first because that is the direction of oncoming traffic. In Europe, however, they must change this automatic response because traffic is now coming from the opposite direction.
This is the first summer of research for all three members of the group. They originally became interested in this project after taking psychology courses during the school year. After taking Memory and Cognition, a psychology course taught by Yee, Craig and Raimondi wanted to learn more about memory. Wuelfing took Introduction to Psychology, another course that was taught by Yee. Although she admits she had "no idea what [her] research project was going to involve" when she signed up for research, Wuelfing said she really liked Yee and wanted to work with her over the summer.
Craig, a psychology major and history minor, sings in the choir. Raimondi, a neuroscience major and art minor, is an orientation leader and has participated in the urban service experience and Guatemala project. Wuelfing, a high jumper on the track team, is thinking about a possible math major.
-- by Nick Berry '09
