A 42-year-old woman with a rare genetic condition has given
scientists insight into the brain areas that underpin the
discomfort we feel when a stranger stands too close. The woman
is a patient with Urbach-Wiethe disease—a very rare disorder
that causes a hardening of brain tissue in the temporal lobes
and wreaks havoc on the amygdala, the region involved in
controlling fear and processing emotion. During years of
studying this individual, California Institute of Technology
neuroscientist Ralph Adolphs, PhD, noticed that she was very
outgoing, occasionally violating others' personal space.  "She
is extremely friendly and wants to approach people more than
normal," Adolphs says.  Collaborating with postdoctoral scholar
Daniel P. Kennedy, PhD, Adolphs compared the woman's sense of
personal space with that of 20 healthy volunteers. The
researchers instructed study participants to stand at a
predetermined distance from an experimenter and to walk toward
the researcher, stopping where they felt most comfortable. T