Oxford University researchers have identified an area of the human brain that appears unlike anything in the brains of some of our closest relatives.
The brain area pinpointed 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.
'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,' says senior researcher 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 ventrolateral frontal cortex area of the human brain, and how these components were connected up with other brain areas. The results were then compared to equivalent MRI data from 25 macaque monkeys.
This 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.
The Oxford University researchers report their findings in the science journal Neuron. They were funded by the UK Medical Research Council.
Professor Rushworth explains: '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.
'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.'
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,' says Professor 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,' says first author Franz-Xaver Neubert of Oxford University. 'This area has been identified with strategic planning and decision making as well as "multi-tasking".'
The Oxford 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 generate speech.
Notes to Editors
- Previous work by the Oxford group and others has shown that the lateral frontal pole is involved in a number of planning and decision-making processes:
- While other brain processes may be focusing on what we are doing now, humans are also good at thinking and planning what we're going to do next so we can quickly move on.
- We also are able to gauge 'how green the grass is on the other side of the fence' – not just evaluating how good the choice we are making is, but also assessing how good the paths we are not taking might be.
- And as well as learning by trial and error, we can learn from watching others attempt tasks. This can enable us to pick up things more quickly, not just from our own experience but learning from others' mistakes as well.
- The paper 'Comparison of human ventral frontal cortex areas for cognitive control and language with areas in monkey frontal cortex' by Franz-Xaver Neubert and colleagues is to be published in the journal Neuron with an embargo of 17:00 UK time / 12 noon US Eastern time on Tuesday 28 January 2013.
- 14 women and 11 men aged 20 years old took part in the study. The resting-state MRI imaging required them to remain still in the MRI scanner.
25 monkeys were anesthetised for the MRI imaging and brought round afterwards. The anaesthetic is also used in hospitals and the MRI scanner is similar to those used with humans. This large set of MRI imaging data has been kept and made available for research, so it can be added to and used again and again as a control dataset in other studies.
- The Medical Research Council has been at the forefront of scientific discovery to improve human health. Founded in 1913 to tackle tuberculosis, the MRC now invests taxpayers' money in some of the best medical research in the world across every area of health. Twenty-nine MRC-funded researchers have won Nobel prizes in a wide range of disciplines, and MRC scientists have been behind such diverse discoveries as vitamins, the structure of DNA and the link between smoking and cancer, as well as achievements such as pioneering the use of randomised controlled trials, the invention of MRI scanning, and the development of a group of antibodies used in the making of some of the most successful drugs ever developed. Today, MRC-funded scientists tackle some of the greatest health problems facing humanity in the 21st century, from the rising tide of chronic diseases associated with ageing to the threats posed by rapidly mutating micro-organisms. http://www.mrc.ac.uk
- Oxford University's Medical Sciences Division is one of the largest biomedical research centres in Europe, with over 2,500 people involved in research and more than 2,800 students. The University is rated the best in the world for medicine, and it is home to the UK's top-ranked medical school.
From the genetic and molecular basis of disease to the latest advances in neuroscience, Oxford is at the forefront of medical research. It has one of the largest clinical trial portfolios in the UK and great expertise in taking discoveries from the lab into the clinic. Partnerships with the local NHS Trusts enable patients to benefit from close links between medical research and healthcare delivery.
A great strength of Oxford medicine is its long-standing network of clinical research units in Asia and Africa, enabling world-leading research on the most pressing global health challenges such as malaria, TB, HIV/AIDS and flu. Oxford is also renowned for its large-scale studies which examine the role of factors such as smoking, alcohol and diet on cancer, heart disease and other conditions.
Journal
Neuron