Google and Harvard University researchers have teamed up to create the most detailed image of a small part of the human brain ever produced .
The work began with obtaining human brain tissue extracted from the cortex of an epileptic patient who underwent brain surgery as part of his treatment.
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Brain tissue from the epileptic patient was cut into approximately 5,300 individual 30 nm sections. Each slice was then imaged using an electron microscope.
The imaging process resulted in the creation of 225 million 2D images. Then a computer was used to stitch the images together and create a 3D representation of the original brain tissue.
Next, the researchers used machine learning algorithms to create 3D segmentations that represent individual cells . Another algorithm was used to characterize 130 million synapses, which were divided into subcompartments. Doing so allowed the labeling of structures of interest such as cilia and myelin.
Human experts reviewed 100 of the cells to correct the work done by the computers. The result is what the team describes as the most detailed map ever created of connections in the human brain . The researchers refer to it as the ‘H01 dataset’.
The team has made the brain map freely available online with their Neuroglancer browser interface. It currently has information for approximately 50,000 cells, displayed in 3D. More to be added soon. Cells are connected by hundreds of millions of tendrils comprising approximately 130 million synapses. Project data currently stands at 1.4 petabytes .
To get an idea of these quantities : a petabyte is 1,024 terabytes. With a single PB, we can host more than 65,000 movies in 4K format (each with an average weight of 15 GB). 1 PB is equivalent to more than 4,000 digital photos per day, throughout our life
The Google team says their goal in creating such tools is to provide resources for studying the human brain using new types of technology.