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Neurosciences

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I feel you, therefore I help you SELENE GALLO is PhD student in the Social Brain Group at the Netherlands Institute for Neuroscience (NIN).

“Your pain is my pain”

↓ Figure A) A snapshot from the videos used in the experiments showing the victim’s hand swatted by a belt. B) The location of the hand representation in the somatosensory cortex that responds to pain by means of activation. This region was targeted by brain stimulation to find a causal relation between brain activity and empathy.

→ Prosocial behaviour is a key aspect of our social life and one of the building blocks of our community. In the last decades, multiple efforts have been made to identify the neural basis of understanding other people’s pain. We know that when we see someone in pain, specific brain areas are activated. Some of this activity correlates with perceived unpleasantness and personal distress, and are thought to code for the unpleasantness of the pain of the other. Activity in other areas, including the somatosensory regions of the cortex that are involved in bodily sense and motor activity, are particularly responsive when the injured body part in pain is visible and in the focus of the attention. These areas are thought to represent the sensory qualities of the pain. Interestingly, some of these key brain regions are also active when we experience pain ourselves, apparently allowing a direct first-person understanding of others’ emotion: ‘Your pain is my pain’. They are considered the neural basis of empathy for pain. The pain vicariously felt while viewing others suffering is then thought to motivate prosocial behaviour. Helping others would then simply serve to reduce the vicariously felt pain. This idea is reinforced by the fact that convicted criminals with psychopathic traits have less activation in such areas of the brain when witnessing someone’s pain. Even though these results are extremely interesting and suggestive, there is still little direct evidence about how the activity in the pain-processing parts of

the brain actually influences helpful behaviour. To test if the vicarious pain-induced brain activity is correlated to prosocial behaviour, we focussed on the somatosensory cortex. We designed an experiment where participants watched videos of someone having their hand swatted with a belt and showing different levels of pain as a result. The volunteers thought the painful stimulation was happening in real life in the next room, and they could decide to reduce the intensity of stimulation, and therefore the level of pain, the person received by donating money they could have taken home. The more pain the participants thought the victim was in, the more money they gave up to lessen it. During the study, the participants’ brain electrical activity from the region that processes sensations (including pain) from the hand was measured. The more active this region was, the more money people donated to help. This confirmed the relationship between vicarious pain and prosocial behaviour. To study if the vicarious pain-induced brain activity is truly responsible for prosocial behaviour, we applied Transcranial Magnetic Stimulation, a non-invasive brain stimulation technique that uses a focussed magnetic field to temporarily interfere with brain activity, over the same region. When the visual representation of the hand was not able to properly function because of our manipulation, the link between donations and

the victim's perceived pain was disrupted: the amount of money people gave no longer matched the level of pain they had witnessed. Something similar happened when we interfered with our volunteers’ hand representation while they were asked just to indicate how much in pain they think the person in the video was: their rating wasn’t in line any more with what they were shown. These findings provide evidence that the brain areas that are involved in feeling pain through vision are necessary for helping-behaviour. They transform the sight of bodily harm into an accurate feeling for how much pain someone else experiences. We use the knowledge represented in these regions to adapt our decision to the needs of others. In the current debate about the role of empathy in helping-behaviours, this study demonstrates that empathy-related brain activity indeed promotes helping by allowing us to detect those that need our assistance. Considering one of the major societal burdens is the lack of understanding of how antisocial behaviour arises and how to successfully reduce it, understanding the neural basis of helping others is a fundamental key stone that will shed light on biological factors that contribute to antisocial behaviour. Consequently, this knowledge will contribute to tailoring educational and therapeutic programmes aimed at reducing antisocial behaviour. Ω

→ Reference S. Gallo et al., eLife 7, e32740 (2018).

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Amsterdam Science magazine issue 9  

Amsterdam Science gives Master’s students, PhD and postdoc researchers as well as staff a platform for communicating their latest and most i...

Amsterdam Science magazine issue 9  

Amsterdam Science gives Master’s students, PhD and postdoc researchers as well as staff a platform for communicating their latest and most i...

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