THE ROUGH GUIDE TO PSYCHOLOGYFriends
Whether we have one or a hundred, most of us probably like to think that
we choose our friends judiciously. Psychological research, however, shows
that friendship is influenced more by convenience, chance and vanity
than by any form of taste or discernment. The influence of convenience
on friendship was demonstrated by a classic study performed in the 1950s
by social psychologist Leon Festinger. He looked at friendships among
couples living in a student complex at MIT, which was composed of seven-
teen buildings, each with ten apartments over two floors. He found that
students were ten times more likely to be friends with someone in their
building than in another building; more likely to be friends with someone
on their own floor; and more likely to be friends with another student on
their floor the nearer that student’s apartment was to their own.
Research on the role of chance in friendships was brought up to date
in dramatic fashion by psychologists at the University of Leipzig in 2008.
At the start of term, they had 54 new psychology students sit in randomly
allocated chairs, arranged in rows. Amazingly, these seating arrangements
The love hormone oxytocin
A chemical called oxytocin, released by the hypothalamus in the
brain, has been dubbed the “love” or “cuddle hormone” because of
the important role it plays in social relationships. It’s released in a
rush during sex and to a lesser extent during other less intimate
social activities. It seems to act as a kind of glue, making social bonds
pleasurable. When scientists block oxytocin receptors in the brains of
mother rats, the rats stop paying any attention to their pups. Similarly,
blocking oxytocin receptors in the usually monogamous prairie vole
causes it to play the field. In humans, sniffing oxytocin compared
with a placebo increases trust and generosity, and improves emotion
recognition. Markus Heinrichs at the University of Zurich, for example,
asked participants to choose how much money to pass to a stranger in
an investment game. The money would be tripled in the transaction,
but there was no guarantee that the receiving investor would share
any of the proceeds. Of the participants who inhaled oxytocin, 45
percent chose to invest the full amount, compared with just 21 percent
of investors who inhaled a placebo. The same effect was not observed
when investors gambled with a computer rather than another player,
suggesting oxytocin specifically affects social trust, not risk perception
in general. Trials are underway to test oxytocin’s therapeutic potential
for conditions such as social phobia and autism.