色情视频

鈥淭he 'little brain鈥� is quite the jack of all trades. Mapping the cerebellum will be an interesting new frontier for the next decade.鈥�

When we say someone has a quick mind, it may be in part thanks to our expanded cerebellum that distinguishes human brains from those of macaque monkeys, for example.

Sometimes referred to by its Latin translation as the 鈥渓ittle brain,鈥� the cerebellum is located close to the brainstem and sits under the cortex in the hindbrain. New research at 色情视频, however, calls the 鈥渓ittle鈥� terminology into question.

The cerebellum plays a versatile role, contributing to our five senses as well as pain, movements, thought, and emotion.
It鈥檚 essentially a flat sheet with the thickness of a crepe, crinkled into hundreds of folds to make it fit into a compact volume about one-eighth the volume of the cerebral cortex. For this reason, the surface area of the cerebellum was thought to be considerably smaller than that of the cerebral cortex.

By using an ultra-high-field 9.4 Tesla MRI machine to scan the brain and custom software to process the resulting images, an 色情视频 neuroimaging expert discovered the tightly packed folds actually contain a surface area equal to 80% of the cerebral cortex鈥檚 surface area. In comparison, the macaque鈥檚 cerebellum is about 30% the size of its cortex.

鈥淭he fact that it has such a large surface area speaks to the evolution of distinctively human behaviors and cognition,鈥� said Martin Sereno, psychology professor, cognitive neuroscientist and director of the 色情视频 MRI Imaging Center. 鈥淚t has expanded so much that the folding patterns are very complex.鈥�

Unprecedented insights

Collaborating with imaging and cerebellum experts from the United Kingdom, Netherlands and Canada, Sereno used customized open source FreeSurfer software that he originally developed with colleagues while at the University of California San Diego to computationally reconstruct the folded surface of the cerebellum. The software also unfolds and flattens the cerebellar cortex so as to visualize it to the level of each individual folia 鈥� or thin leaf like fold.

A pioneer in brain imaging who has leveraged functional MRI to uncover visual maps in the brain, Sereno found that when the cerebellum is completely unfolded, it forms a strange 鈥渃repe鈥� four inches wide by three feet long. The findings were published this week in a  in PNAS (Proceedings of the National Academy of Sciences).

鈥淯ntil now we only had crude models of what it looked like,鈥� Sereno said. 鈥淲e now have a complete map or surface representation of the cerebellum, much like cities, counties, and states.鈥�

Puzzle pieces

Previous research discovered that while there were many similarities between the cortex and the cerebellum, there was one key difference. In the cerebral cortex, regions representing different parts of the body are arranged roughly like they are in the actual body: juxtaposed and orderly. But in the cerebellum, they were placed more randomly.

鈥淵ou get a little chunk of the lip, next to a chunk of the shoulder or face, like jumbled puzzle pieces,鈥� Sereno explained. 鈥淲hen you think of the cognition required to write a scientific paper or explain a concept, you have to pull in information from many different sources. And that鈥檚 just how the cerebellum is set up.鈥�   Those parts of the cerebellum are therefore set up to pull in and coordinate information from disparate parts of the body.

鈥淣ow that we have the first high resolution base map of the human cerebellum, there are many possibilities for researchers to start filling in what is certain to be a complex quilt of inputs, from many different parts of the cerebral cortex in more detail than ever before,鈥� Sereno said.
For instance, there is some recent evidence that people who suffer cerebellum damage have difficulty processing emotion.

鈥淭he 鈥榣ittle brain鈥� is quite the jack of all trades,鈥� Sereno said. 鈥淢apping the cerebellum will be an interesting new frontier for the next decade.鈥�

Collaborations

Sereno began working on imaging while at the University College London, and continued to work on processing the imaging data and analysis at 色情视频.

Sereno worked closely with co-author and neuroscientist J枚rn Diedrichsen, now at the University of Western Ontario, London, Canada. Other collaborators include Mohamed Tachrount at the University College London, Guilherme Testa-Silva at Harvard University, Helen d鈥橝rceuil at Massachusetts General Hospital, and Chris De Zeeuw at the Netherlands Institute for Neuroscience. Grant funding for this research came from the National Institutes of Health and the Royal Society Wolfson Fellowship.