IBT | What separates man from monkey? (Aside from some stricter
etiquette around poop-flinging, that is.) Some researchers think they’ve
found one key feature that’s unique to Homo sapiens: an area of the brain that seems to have no equivalent in other primates.
“We tend to think that being able to plan into the future, be
flexible in our approach and learn from others are things that are
particularly impressive about humans,” Oxford experimental psychologist
Matthew Rushworth said in a statement. “We've identified an area of the
brain that appears to be uniquely human and is likely to have something
to do with these cognitive powers.”
Rushworth and colleagues compared brain scans of 25 adult humans to the brain scans of 25 macaque monkeys.
“The brain is a mosaic of interlinked areas,” Rushworth says. “We
wanted to look at this very important region of the frontal part of the
brain and see how many tiles there are and where they are placed. We
also looked at the connections of each tile -- how they are wired up to
the rest of the brain -- as it is these connections that determine the
information that can reach that component part and the influence that
part can have on other brain regions.”
As the team reported on Tuesday in the journal Neuron [PDF],
it found that one of those “tiles” on the brain scan seems wholly
human: A certain area in the frontal cortex, called the lateral frontal
pole prefrontal cortex, seems to have no equivalent in the macaque. This
is particularly interesting because the surrounding brain region is
thought to be involved in a wide range of cognitive functions. Damage to
the ventrolateral frontal cortex affects a person's language abilities,
and the brain region is also implicated in a number of psychiatric
disorders.
