What separates man from monkey? Oxford scientists have discovered an area of the brain linked to strategic decision-making that is unique to humans and appears to have no equivalent in other primates.
The brain area pinpointed in the human frontal cortex is known to be intimately involved in some of the most advanced planning and decision-making processes that we think of as being especially human, researchers said.
"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," said Professor Matthew Rushworth of Oxford University's Department of Experimental Psychology.
MRI imaging of 25 adult volunteers was used to identify key components in the an area of the human brain called the ventrolateral frontal cortex.
The study also investigated how these components were connected up with other brain areas. The results were then compared with equivalent MRI data from 25 macaque monkeys.
The ventrolateral frontal cortex area of the brain is involved in many of the highest aspects of cognition and language, and is only present in humans and other primates.
Some parts are implicated in psychiatric conditions like ADHD, drug addiction or compulsive behaviour disorders. Language is affected when other parts are damaged after stroke or neurodegenerative disease.
A better understanding of the neural connections and networks involved should help the understanding of changes in the brain that go along with these conditions.
From the MRI data, the researchers were able to divide the human ventrolateral frontal cortex into 12 areas that were consistent across all the individuals.
"Each of these 12 areas has its own pattern of connections with the rest of the brain, a sort of "neural fingerprint", telling us it is doing something unique," said Rushworth.
The researchers were then able to compare the 12 areas in the human brain region with the organisation of the monkey prefrontal cortex.
Overall they were very similar, with 11 of the 12 areas being found in both species and being connected up to other brain areas in very similar ways.
However, one area of the human ventrolateral frontal cortex had no equivalent in the macaque - an area called the lateral frontal pole prefrontal cortex.
"We have established an area in human frontal cortex which does not seem to have an equivalent in the monkey at all," said first author Franz-Xaver Neubert.
"This area has been