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“Unique” brain area seen only in humans

Jan. 29, 2014
Courtesy of Oxford University
and World Science staff

Ox­ford Uni­vers­ity re­search­ers have iden­ti­fied a small zone at the very front of the hu­man brain that looks un­like an­y­thing in the brains of some of our clos­est mon­key rel­a­tives.

The brain ar­ea is con­sid­ered to be in­ti­mately in­volved in some of the most ad­vanced plan­ning and de­ci­sion-mak­ing pro­cesses that we think of as be­ing es­pe­cially hu­man.

In this schematic, the later­al front­al pole pre­front­al cor­tex is shown as the dark red area at the right. (Credit: Neu­ron, Neu­bert et al.)


“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. 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 in­ves­ti­ga­tor Mat­thew Rush­worth of Ox­ford Uni­vers­ity.

The sci­en­tists scanned the brains of 25 adult vol­un­teers us­ing Mag­net­ic Res­o­nance Im­ag­ing to iden­ti­fy key com­po­nents of a brain re­gion called the ven­tro­lat­eral front­al cor­tex. The re­sults were then com­pared to equiv­a­lent da­ta from 25 ma­caque mon­keys.

The ven­tro­lat­eral front­al cor­tex is in­volved in many of the high­est as­pects of cog­ni­tion and lan­guage, and is only found in hu­mans and their close rel­a­tives such as apes and mon­keys, said the in­vest­iga­tors, who re­ported their find­ings in the re­search jour­nal Neu­ron.

“The brain is a mo­sa­ic of in­ter­linked ar­e­as. 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,” said Rush­worth.

“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.”

The re­search­ers di­vid­ed the hu­man ven­tro­lat­eral front­al cor­tex in­to 12 ar­e­as that were con­sist­ent across all peo­ple. “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.

Mon­keys shared si­m­i­lar struc­ture in 11 of the 12 ar­e­as, with si­m­i­lar con­nec­tions to oth­er brain ar­e­as, the sci­en­tists found. But one ar­ea of the hu­man ven­tro­lat­eral front­al cor­tex had no equiv­a­lent in the ma­caque—an ar­ea called the lat­er­al front­al pole prefront­al cor­tex.

This “does not seem to have an equiv­a­lent in the mon­key at al­l,” said co-author Franz-Xaver Neu­bert of Ox­ford Uni­vers­ity. “This ar­ea has been iden­ti­fied with stra­te­gic plan­ning and de­ci­sion mak­ing as well as “mul­ti­-tasking.’“

The re­search group al­so found that the au­di­to­ry parts of the brain were very well con­nect­ed with the hu­man prefront­al cor­tex, but much less so in the ma­caque. The re­search­ers sug­gest this may be crit­i­cal for our abil­ity to un­der­stand and speak.


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Oxford University researchers have identified a small zone at the very front of the human brain that looks unlike anything in the brains of some of our closest relatives. The brain area is considered to be intimately involved in some of the most advanced planning and decision-making processes that we think of as being especially human. “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. 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 investigator Matthew Rushworth of Oxford University. The scientists scanned the brains of 25 adult volunteers using Magnetic Resonance Imaging to identify key components of a brain region called the ventrolateral frontal cortex. The results were then compared to equivalent data from 25 macaque monkeys. The ventrolateral frontal cortex is involved in many of the highest aspects of cognition and language, and is only found in humans and their close relatives such as apes and monkeys, said the researchers, who reported their findings in the science journal Neuron. “The brain is a mosaic of interlinked areas. 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,” said Rushworth. “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.” The researchers divided the human ventrolateral frontal cortex into 12 areas that were consistent across all people. “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. Monkeys shared similar structure in 11 of the 12 areas, with similar connections to other brain areas, the scientists found. But one area of the human ventrolateral frontal cortex had no equivalent in the macaque—an area called the lateral frontal pole prefrontal cortex. This “does not seem to have an equivalent in the monkey at all,” said co-author Franz-Xaver Neubert of Oxford University. “This area has been identified with strategic planning and decision making as well as “multi-tasking.’“ The research group also found that the auditory parts of the brain were very well connected with the human prefrontal cortex, but much less so in the macaque. The researchers suggest this may be critical for our ability to understand and speak.