The reason why we help others at a cost to ourselves
has long presented a puzzle for scientists. Why do some of us do it
more than others? And are we doing it because we are truly moved by the
suffering of others or simply because we feel we ought to return a favour
or even get something in return? Looking at behaviour alone, it can be
hard to tell. Both empathy and the principle of reciprocity - giving to
return a favour or expecting others to do so - are proposed explanations
for altruism which have been impossible to separate until now.
Using functional magnetic resonance imaging (fMRI), which measures blood flow changes in the brain, a new study
suggests that specific differences in connectivity between brain
regions can predict whether someone is an empathy-driven altruist, a
reciprocity-driven altruist - or just selfish.
In the experiment, 34 female participants were divided into two groups.
Those in the "empathy" group witnessed an actor receive painful electric
shocks - and received shocks themselves (so they knew it hurt). In the
"reciprocity" group, participants were paired up with actors who kindly
paid money so the participant received fewer shocks (although both
groups received the same number of shocks overall).
Next, their brains were scanned. During the scanning, participants were
asked to split a sum of money between themselves and another person. For
the empathy group, the other person receiving the money was sometimes
the partner they saw shocked. In the reciprocity group, the person was
sometimes the partner who paid for the participant to receive fewer
shocks. At other times, participants were simply asked to split the cash
between themselves and a neutral person who neither received shocks nor
did anything nice. The researchers could therefore divide the
participants into those empathy-driven altruists and reciprocity-driven
altruists based on the first part of the experiment. They could also use
the way participants split the money in the second part to identify
selfish individuals among these participants.
Unsurprisingly, the initial analysis showed that participants gave, on
average, larger sums of money to the empathy and reciprocity partners
than to the neutral partner - and that both groups were equally
generous. Those that most regularly chose splits involving more money
for themselves than the other were classified as "selfish". But this was
just the starting point. The researchers used a complex and
sophisticated follow-up to gain deeper insight.
By looking at the timing of activity in the anterior cingulate cortex
(known for a host of functions from pain and conflict to learning), the
anterior insula cortex (associated with arousal and emotion) and the
ventral striatum (associated with rewards and learning), the researchers
created models of how information was passed between these areas. Then a
computer algorithm tried to guess, based on these models, whether an
individual's altruistic decision had been motivated by empathy or by
reciprocity. The high accuracy of these guesses at 77% shows the two
groups of participants had brain activity patterns that differed enough
to classify.
In empathy-driven altruism, the anterior insula (emotion and arousal)
and ventral striatum (rewards) showed a lower than average connectivity,
while reciprocity-driven altruism showed increased connectivity between
these regions. Connectivity in this sense can be imagined as how much
one area is "talking to" another. Although the functions of these areas
are broadly known, the meaning of changes in connectivity is still
difficult to interpret.
By looking at the timing of activity in the anterior cingulate cortex
(known for a host of functions from pain and conflict to learning), the
anterior insula cortex (associated with arousal and emotion) and the
ventral striatum (associated with rewards and learning), the researchers
created models of how information was passed between these areas. Then a
computer algorithm tried to guess, based on these models, whether an
individual's altruistic decision had been motivated by empathy or by
reciprocity. The high accuracy of these guesses at 77% shows the two
groups of participants had brain activity patterns that differed enough
to classify.
In empathy-driven altruism, the anterior insula (emotion and arousal)
and ventral striatum (rewards) showed a lower than average connectivity,
while reciprocity-driven altruism showed increased connectivity between
these regions. Connectivity in this sense can be imagined as how much
one area is "talking to" another. Although the functions of these areas
are broadly known, the meaning of changes in connectivity is still
difficult to interpret.
The
results also showed differences in brains of those who had been
classified as selfish or altruistic based on their decisions. Selfish
individuals showed lower than average connectivity from the anterior
cingulate cortex to the anterior insula whereas altruists had increased
connectivity between these regions.
Can we learn to be more altruistic?
When it comes to implications, the differences between primarily selfish
or primarily altruistic participants may be the most important finding.
Inducing empathy, by seeing someone shocked, increased giving and
associated neural connectivity for selfish individuals - they were more
generous to the shocked partners than to the neutral person. The
altruistic people, however, shared just as much with the neutral person
as the shocked partner. The opposite was true for the reciprocity
effect: increased giving to the partner who paid to prevent their shocks
was seen in altruistic but not selfish participants.
One could speculate that this implies that altruistic participants are
already giving because of empathic motivation, so increasing empathy
makes no difference - they are at their "empathy capacity". Similarly,
selfish participants may already be acting due to motivations more
likely to benefit themselves too, such as reciprocity.
Research on altruism regularly concludes that people have an empathetic motivation
but this paper suggests potential for future studies to check whether
this is the case for each individual participant. The authors also open
doors to more specific measures and targets for further research on
reciprocity and empathy.
The paper shows the importance of analysing subtle differences in brain communication rather than overall activity.
Looking at different brain regions working together, rather than in
isolation, can identify previously elusive psychological concepts, such
as underlying motivations.
Future research is needed on whether these increases in altruism and
neural connectivity could last, perhaps with ongoing training. For
example, if the techniques used to induce empathy in the study could be
employed in some sort of treatment for antisocial behaviour.
However, charities can already make the most of the current findings.
They suggest empathy-inducing appeals may be most effective for new
supporters, who are not yet "altruistic enough" to donate. Existing
supporters, who are already altruistic, may respond more to receiving a
token gift they feel they can reciprocate by increasing their donations.
The effectiveness of these techniques, already used by many charities,
may be explained by the findings. But with limited resources, new
insight into cognitive processes that might be harnessed by appeals
could help society be a bit more generous.
http://www.sott.net/article/313772-Brain-scan-may-reveal-if-you-are-a-true-altruist-or-driven-by-self-interest
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