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Measures

2.2.1 Perceived Stress Scale (Cohen et al., 1983)

The Perceived Stress Scale (PSS) is a measure of one's stress levels over the last month that consists of 14 questions measured on a 5-item scale (1—Never to 5—Very Often). These questions ask participants about their feelings of control, sense of management, and levels of stress in their life over the last month. [...]

2.2.2 Mindful Attention Awareness Scale (Brown & Ryan, 2003)

The Mindful Attention Awareness Scale (MAAS) is a 15-item questionnaire measured on a 6-item scale (1—Almost Always to 6—Almost Never) that assesses an individual's trait mindfulness. The questions ask participants about how mindful they are of their surroundings (e.g., “I find it difficult to stay focused on what's happening in the present.”).[...]

2.2.3 Mindfulness and control audiotapes (Cropley et al., 2007)

One of two 10-min-long audio tapes was randomly selected for each participant to listen to. The mindfulness audio tape instructed the participants to remain open-minded about the activity and to specifically focus on their bodily sensations and breathing while simultaneously accepting all thoughts that occur. The control audiotape simply described the scenery of the English countryside. This measure was included because it has been shown through previous research to induce feelings of mindfulness in participants.[...]

2.2.4 State Mindfulness Scale (Tanay & Bernstein, 2013)

The State Mindfulness Scale (SMS) measures one's state mindfulness level. It is composed of 21 questions that are evaluated on a 5-point Likert scale (0–Not at all to 4–Very much). These questions ask the participants to analyze their personal experiences during an audio recording that immediately preceded the scale. [...]

2.2.5 Montreal Imaging Stress Task (Dedovic et al., 2005)

The Montreal Imaging Stress Task (MIST) is a computerized arithmetic test that presents social evaluative threats to participants. The goal of the MIST is to produce psychological stress. Our modified MIST was composed of control and experimental conditions. Participants who were assigned to the control condition were shown a series of math tasks they were asked to solve on their computers. However, participants in the experimental condition were shown a series of math tasks designed to cause stress due to their greater difficulty and reduced time allotted to solve. Additionally, the participants in the experimental condition were shown information after each task that discussed their performance. This information served as a social evaluative threat by showing them the performance of other participants, which was manipulated to always be better than the participant's performance. [...]

2.2.6 Intergroup Attitudes and Beliefs Inventory (Ryan et al., 2007)

The Intergroup Attitudes and Beliefs Inventory consisted of 64 questions. This inventory's goal was to measure a person's perceptions of Black and White people in the United States. Sixteen of the 64 questions were measured on a 0–100 scale with the participants indicating what percentage of White or Black Americans they believed to possess a certain trait [...]

2.3 Procedure

First, participants accessed the survey through Qualtrics and were directed to complete the PSS, which was used to measure their stress levels over the last month. Participants then completed the MAAS to assess their trait mindfulness. Next, all participants were instructed to listen to a 10-min audio recording. Each participant was randomly assigned to listen to either a mindfulness audio recording that told the participant to focus on their breathing and bodily experiences while maintaining an open mind about the activity, or a control audio recording that described an English countryside. After listening to the audio recording, participants were required to complete the SMS which was used to determine the audio's impact on each participant's state mindfulness.

Participants then installed Inquisit and completed the MIST, where they were randomly assigned to the experimental (stress) or control (no stress) condition. After completing the MIST, participants returned to Qualtrics and answered three questions about the MIST (e.g., “How difficult did you find the previous task?” “How stressful did you find the previous task?” “How much did you like the previous task?”). Lastly, the participants completed the 64-question Intergroup Attitudes and Beliefs Inventory. After all of the tasks described above were finished, the participants were debriefed and told that the study had ended.