The brain is still largely a mystery to modern science. Whilst we’ve mapped out the majority of what parts do what we’re still in the dark about how they manage to accomplish their various feats. Primarily this is a function of the brain’s inherit complexity, containing some 100 trillion connections between the billions of neurons that make up its meagre mass. However like all problems the insurmountable challenge of decrypting the brain’s functions is made easier by looking at smaller parts of it. Researchers at the USC Viterbi School of Engineering and the Wake Forest Baptist Medical Center have been doing just that and have been able to recreate a critical part of the brain’s functionality in hardware.
The researchers have recreated the part of the brain called the hippocampus, the part of the brain that’s responsible for translating sensory input into long term memories. In patients that suffer from diseases like Alzheimer’s this is usually the first part that gets damaged, preventing them from forming new memories (but leaving old ones unaffected). The device they have created can essentially replace part of the hippocampus, facilitating the same encoding functions that a non-damaged section would provide. Such a device has the potential to drastically increase the quality of life of many people, enabling them to once again form new memories.
The device comes out of decades of research into how the brain processes sensory input into long term memories. The researchers initially tested their device on laboratory animals, implanting the device into healthy subjects. Then they recorded the input and output of the hippocampus, showing how the signals were translated for long term storage. This data was then used to create a model of this section of the hippocampus, allowing the researchers to then take over the job of encoding those signals. Previous research showed that, even when the animal’s long term memory function was impaired through drugs, the prosthesis was able to generate new memories.
That in and of itself is impressive however the researchers have been replicating their work with human patients. Using nine test subjects, all of whom had the requisite electrodes implanted in the right regions to treat chronic seizures, the researchers utilized the same process to develop a human based model. Whilst they haven’t yet used that to help in the creation of new memories in humans they have proven that their human model produces the same signals as the hippocampus does in 90% of cases. For patients who currently have no ability to form new long term memories this could very well be enough to drastically improve their quality of life.
This research has vast potential as there are many parts of the brain that could be mapped in the same way. The hippocampus is critical in the formation of non-procedural long term memories however there are other sections, like the motor and visual cortices, which could benefit from similar mapping. There’s every chance that those sections can’t be mapped directly like this but it’s definitely an area of potentially fruitful research. Indeed whilst we still not know how the brain stores information we might be able to repair the mechanisms that feed it, and that could help a lot of people.