According to the facial feedback hypothesis, people's affective responses can be influenced by their own facial expression (e.g., smiling, pouting), even when their expression did not result from their emotional experiences. For example, Strack, Martin, and Stepper (1988) instructed participants to rate the funniness of cartoons using a pen that they held in their mouth. In line with the facial feedback hypothesis, when participants held the pen with their teeth (inducing a "smile"), they rated the cartoons as funnier than when they held the pen with their lips (inducing a "pout"). This seminal study of the facial feedback hypothesis has not been replicated directly. This Registered Replication Report describes the results of 17 independent direct replications of Study 1 from Strack et al. (1988), all of which followed the same vetted protocol. A meta-analysis of these studies examined the difference in funniness ratings between the "smile" and "pout" conditions. The original Strack et al. (1988) study reported a rating difference of 0.82 units on a 10-point Likert scale. Our meta-analysis revealed a rating difference of 0.03 units with a 95% confidence interval ranging from -0.11 to 0.16.

The late positive potential (LPP) reflects increased attention to emotional versus neutral stimuli in adults. To date, very few studies have examined the LPP in children, and whether it can be used to measure patterns of emotional processing that are related to dispositional mood characteristics, such as temperamental fear and anxiety. To examine this question, 39 typically-developing 5–7 year olds (M age in months = 75.27, SD = 5.83) passively viewed complex emotional and neutral pictures taken from the International Affective Picture System. Maternal report of temperamental fear and anxiety was obtained and fearful behavior during an emotional challenge was observed. As documented in adults, LPP amplitudes to pleasant and unpleasant stimuli were larger than to neutral stimuli, although some gender differences emerged. Larger LPP amplitude differences between unpleasant and neutral stimuli were associated with greater observed fear. The LPP as a measure of individual differences in emotional processing is discussed.

Cognitive emotion regulation strategies, such as reappraising the emotional meaning of events, are linked to positive adjustment and are disrupted in individuals showing emotional distress, like anxiety. The late positive potential (LPP) is sensitive to reappraisal: LPP amplitudes are reduced when unpleasant pictures are reappraised in a positive light, suggesting regulation of negative emotion. However, only one study has examined reappraisal in children using the LPP. The present study examined whether directed reappraisals reduce the LPP in a group of 5- to 7-year-olds, and correlate with individual differences in fear and anxiety. EEG was recorded from 32 typically-developing children via 64 scalp electrodes during a directed reappraisal task. Mothers reported on child anxiety. Fearful behavior was observed. As predicted, LPP amplitudes were larger to unpleasant versus neutral pictures; counter to predictions, the LPP was not sensitive to reappraisal. The degree to which unpleasant versus neutral pictures elicited larger LPPs was correlated with greater anxiety and fear. Results suggest that reappraisal in young children is still developing, but that the LPP is sensitive to individual differences related to fear and anxiety. The utility of the LPP as a measure of cognitive emotion regulation and emotional processing biases in children is discussed.

The late positive potential (LPP), which is reduced following the use of reappraisal, is a potential neurosignature for emotion regulation capacity. This sensitivity of the LPP to reappraisal is rarely studied in children. We tested whether, in 26 typically-developing seven- to nine-year-olds, LPP amplitudes were reduced following reappraisal and whether this effect varied with age and anxiety. For the full sample, LPPs were not significantly reduced following reappraisal. As predicted, reductions in the LPP following reappraisal were greater for older children and those showing less anxiety. The utility of the LPP as a neurosignature for emotion regulatory capacity is discussed.