Emotional primes modulate the responses to others’ pain: an ERP study

Abstract

Previous event-related potential (ERP) and brain imaging studies have suggested observer responses to others' pain are modulated by various bottom-up and top-down factors, including emotional primes. However, the temporal dynamics underlying the impact of emotional primes on responses to others' pain remains poorly understood. In the present study, we explored effects of negative, neutral, and positive emotional priming stimuli on behavioral and cortical responses to visual depictions of others in pain. ERPs were recorded from 20 healthy adults, who were presented with painful and non-painful target pictures following observation of negative, neutral, and positive emotional priming pictures. ERP analyses revealed that relative to non-painful pictures, differential P3 amplitudes for painful pictures were larger followed by negative primes than either neutral or positive primes. There were no significant differential P3 amplitudes for painful pictures relative to non-painful pictures were found followed neutral and positive emotional primes. These results suggest that negative emotional primes strengthen observers' attention toward others' pain. These results support the threat value of pain hypothesis.

A threat to a virtual hand elicits motor cortex activation

“…Our study reproduced the results of (Fan and Han, 2008, Li and Han, 2010, Meng et al, 2012, Meng et al, 2013 in terms of ERP correlates, showing significant evidence that pain effects were found, with the mean P450 showing greater amplitudes at the CP3 electrode location in the HAND compared to the TABLE condition.…”

“…We conducted further post-hoc pairwise comparisons between both conditions (hand and table) at parietal and central electrodes; the paired samples t-test were significant for the P450 at C3 and CP3 electrodes (t(18)=3.438, P=0.003 and t(18)=3.637, P=0.002, respectively). These results are consistent with the P450 effects induced when a pain estimation task was performed in previous studies (Fan and Han, 2008, Li and Han, 2010, Meng et al, 2012.…”

“…This setup substitutes a person's own body by a virtual body seen from a first person perspective (1PP), such that when participants look down towards their body they would see a virtual body replacing their own (Figure 1). In the experiment the participant's stationary right virtual hand, which was collocated with the real right hand resting on a table, was repeatedly threatened by a virtual knife, thereby reproducing in IVR previously conducted pain observation experiments (Avenanti et al, 2006, Bufalari et al, 2007, Gu and Han, 2007, Fan and Han, 2008, Li and Han, 2010, Meng et al, 2012, Meng et al, 2013. The painful stimulation was compared to a control where the same knife attacked only the virtual table that was spatially registered with the real table on which the hand was resting (Figure 1).…”

“…Studies that have examined the Event Related Potential (ERP) temporal dynamics involved in empathy, measured as the response to observation of pain in others, especially prominent in the motor cortex area, have found greater P450 responses for painful images compared to neutral images (Fan and Han, 2008, Li and Han, 2010, Meng et al, 2012, Meng et al, 2013. These effects were modulated by the realism of the presentation and were stronger with greater realism (Fan and Han, 2008).…”

“…In order to study the effects of the stimuli on the pain sensitivity, Event Related Potential (ERP) components were analyzed as in (Fan and Han, 2008, Li and Han, 2010, Meng et al, 2012. The stimulus locked ERP helped us determine the pain related levels of the participants with respect to the HAND condition, where a higher P450 activity was expected in case of a pain response.…”