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Study 1

Method

Participants and Design Thirty-four (25 female and 9 male) undergraduate students in the Netherlands participated in the experiment [...]. Four independent variables were included in a 2 (time: pretest or posttest) X 2 (prime: skinhead or elderly) X 2 (type of stereotype: skinhead or elderly) X 2 (stereotype negated: skinhead or elderly) design. [...]

Procedure

Phase 1: Pretest of stereotype activation. On entering the laboratory, participants were randomly assigned to either the Skinhead or the Elderly Stereotype Negation Conditions. In Phase 1, all participants were presented with a primed Stroop task to examine spontaneous stereotype activation. They were informed that they would be presented with a series of trials on a Macintosh Performa, which consisted of an initial asterisk and two words that would appear in sequence. They were further instructed to read the first word silently and to state the color of the second word into the microphone as quickly and as accurately as possible. [...] In the Stroop task, a total of 128 trials were randomly presented in which the elderly and skinhead primes were presented with each of the 16 traits in four different colors—red, blue, green, and yellow. [...]

Phase 2: Negation training. Phase 2 used a new negation training procedure in which participants were informed that they would be presented with a photograph with a trait below it on a computer screen. Participants in the Skinhead Stereotype Negation Condition were instructed to try not to think of cultural associations when seeing the photograph of the skinhead. Accordingly, they were asked to press "NO" on a button box when they saw the photograph of the skinhead and under it a word associated with skinheads. They were further instructed to press "YES" when they saw the photograph of the skinhead and a word not normally associated with skinheads. [...] When seeing the picture of the elderly person, alternatively, the same participants were instructed to try to think of cultural associations. When they saw the photograph of the elderly person and a word associated with the elderly, they were required to press "YES" and to press "NO" when they saw the photograph of the elderly person and a word not normally associated with the elderly. The other half of the participants, those in the Elderly Stereotype Negation Condition, were given the opposite instructions. [...] On each trial, participants were presented with a photograph for 500 ms before a word appeared under the photograph. [...] Participants completed the 480 trials in approximately 45 min.

Phase 3: Pastiest of stereotype activation. In Phase 3, the primed Stroop task was once more used to examine the effect of the training phase on subsequent stereotype activation. Although the same stimulus material was used in the pretest and the posttest Stroop task, the primes in these phases were category words and not photographs as in the negation training in Phase 2. Furthermore, the target words used in the training task were 20 "new" stereotypes of the elderly and skinheads not used in Phase 1 and 3. [...]

Study 2

Method

Participants and Design Twenty-nine (13 female and 16 male) undergraduate students in the Netherlands participated [...]. Four independent variables were included in a 4 (time of Stroop task: 0, 2, 6, or 24 hr subsequent to the initial session) X 2 (prime: elderly or skinhead) X 2 (type of stereotype: elderly or skinhead) X 2 (stereotype negated: skinhead or no stereotype) design. Only the Stereotype Negated factor was between subjects; all other factors were within subjects.

Procedure The experimental procedure was similar to Study 1, except that participants in the No Stereotype Negation Condition received no training, only the primed Stroop task. Participants in the Skinhead Stereotype Negation Condition, alternatively, after initially receiving the full six blocks of trials in negating skinhead stereotypes, were presented with the primed Stroop task. [...] During the 480 trials, these participants were instructed not to stereotype skinheads and to stereotype the elderly. [...] All participants completed the primed Stroop task at four separate intervals. These intervals were either immediately at the beginning of the first session for the No Stereotype Negation Condition or directly after the training for the Skinhead Stereotype Negation Condition, followed by a repeated Stroop task 2, 6, and 24 hr subsequent to the first session.

Study 3

Method

Participants and Design Forty (21 female and 19 male) White undergraduates in the United States participated [...]. Five independent variables were included in a 2 (time: pretest or posttest) X 2 (stereotype prime: Black or White) X 2 (valence of prime: positive or negative word) X 2 (type of face: Black or White) X 2 (stereotype negated: stereotype negation or stereotype maintain) design. [...]

Procedure

Phase 1: Pretest of stereotype activation. In Phase 1, we used a person categorization task to measure automatic stereotype activation. [...] Participants were also told that they were in the distractor condition and that before each photograph a distractor word that was unrelated to the categorization task would "appear for a short time." They were asked to read the word silently and "to judge as quickly and accurately as possible whether the person in the subsequent photograph is Black or White and to press the appropriate key." [...] The trait primes included 8 positive and 8 negative stereotypes for Blacks (e.g., athletic, poor) and Whites (e.g., ambitious, uptight) and 16 filler traits (e.g., friendly, confused). [...] Next, a blank screen appeared for 50 ms before the onset of a photograph. Forty-eight portraits of Black men and 48 portraits of White men scanned from college yearbooks were presented [...] on the computer screen until the participant responded. [...] Participants were presented with two blocks of trials. Each block consisted of 48 trials in which each positive and negative stereotypical trait and each filler trait was presented once. [...] Across blocks, pictures of Black and White men were paired once with the 8 positive and 8 negative Black and White stereotypical traits and the 16 filler traits, resulting in a total of 96 trials. [...]

Phase 2: Stereotype negation training. The procedure and instructions for the training task were virtually identical to those used in Study 1. [...] Participants were informed that they would be presented on the computer screen simultaneously with a photograph of a Black or a White person and a Black or White stereotype underneath it. We used 48 photographs of White males, 48 photographs of Black males, and 48 target traits, which included 12 positive and negative White stereotypes and 12 positive and negative Black stereotypes. In the previous studies all participants were instructed to negate stereotypes related to a specific category [...] and to respond affirmatively to associations not stereotypic of that same category [...]. Furthermore, these same participants were instructed to respond positively to stereotypes related to a different category (e.g., elderly photograph-elderly stereotypes) and to respond negatively to associations not stereotypic of that category (e.g., elderly photograph-skinhead stereotypes). [...] In the present study, we decided to simplify the design by instructing half of the participants to negate stereotypes related to both Black and White categories and half of the participants to not negate stereotypes related to these categories. Thus participants in the Stereotype Negation Condition were instructed to negate racial stereotypes by responding "NO" when presented with a photograph of a White person and a White stereotype or a photograph of a Black person and a Black stereotype. They were also told to respond "YES" to stereotype-inconsistent word-picture pairings. Conversely, participants in the Stereotype Maintain Condition were instructed to respond "YES" when they were presented with a photograph of a White person and a White stereotype or a photograph of a Black person and a Black stereotype. They were also told to respond "NO" to stereotype-inconsistent word-picture pairings. In total, 384 trials were presented consisting of four blocks of 96 trials in which the 48 words were paired with a photograph of a White and Black person. [...]

Phase 3: Posttest of stereotype activation. In Phase 3, a posttest of the person categorization task was used to examine the effect of the training phase on subsequent stereotype activation. Once again, the stereotypes and photographs in the pre- and posttest of the categorization task were the same, but different from the stimuli in the training task in Phase 2.