Page 79 - Demo

Attractiveness modulates attention774ProcedureThe experiment involved a dot-probe paradigm (MacLeod et al., 1986; for a review, see van Rooijen et al., 2017). In the task, two stimuli were presented next to each other, each centralized in one half of the screen. All paired images consisted of an attractive or unattractive face and an intermediately attractive face. Location of the stimuli and the probe was balanced between trials. Participants only saw pictures of opposite-sex individuals. In total, participants performed 80 trials presented in random order (excluding five practice trials).1The sole instruction participants received was to tap on a black dot as fast as they could (Figure 1). Every trial started with a dot appearing in the midbottom of the screen until participant response. Subsequently, two stimuli (i.e., an (un)attractive and an intermediately attractive face) were displayed for 300 ms. Next, a dot (probe) appeared in place of either the (un)attractive face or in place of the intermediately attractive face. The probe remained on the screen until participant response. Every trial ended with a 2,000-ms intertrial interval. The RT of the participant from tapping on the probe from stimulus offset was used as a dependent variable in all further analyses.After the experiment, participants validated all 40 stimuli (presented in a random order) by rating their attractiveness on a 7-point ordinal scale (very unattractive, fairly unattractive, somewhat unattractive, neutral, somewhat attractive, fairly unattractive, very unattractive). We used these scores to determine whether the ratings of the participants aligned well with the predetermined attractiveness categories (attractive, intermediate, unattractive).Statistical AnalysesWe first filtered out extremely fast or slow responses. For fast trials, we excluded all trials with RTs < 250 ms. The upper exclusion level was determined per subject. Specifically, we computed the median RT and the median absolute deviation (Leys et al., 2013) per subject. The following conservative filter was applied per subject (upper limit RT = median + 2 * median absolute deviation). The lower and upper filter resulted in exclusion of 4.7% overall. Hereafter, we mean-centered the RTs by subject (i.e., how fast did the participant react relative to their own mean RT).1 Due to a coding error, an additional sensitive, touchable area was presented in the middle of the screen on the slide showing the probe. Technically, a participant’s RT could be logged if they clicked this additional sensitive area instead of the probe. However, because this sensitive area was transparent and thus invisible to the participants, it is highly unlikely that they tapped within that area instead of tapping the probe. Also, the fact that no participants had an extreme amount of extremely fast or extremely slow responses suggests that they were following the instruction to tap the probe properly.Tom Roth.indd 77 08-01-2024 10:41