Scientists have published the first draft of the most detailed map to date of the human brain, the Human Brain Atlas. The researchers say it’s the start of a “new era in brain science” in greater understanding of one of the most complex known physical objects in the universe.
The project started almost a decade ago, and the resulting database shows the brain is vastly more complex than previously known. The study has so far released 21 papers to multiple journals.
Brain Atlas of Over 3,300 Cell Types
Although called the Human Brain Atlas, the study also examines primate brains like gorillas and chimpanzees. So far, the study has found over 3,300 types of brain cells and visualized them in detail.
Although the cells contain the same DNA, they have different appearances and behave in different ways. About 16,000 genes can be turned on in different combinations within the neurons.
Despite having such an array of cell types, they all match up with those found in chimpanzees and gorillas. But the way genes are combined and turned on may be what makes human brains different, particularly as related to the development of synapses, the connections between neurons.
“The papers reveal that the cell types that make up a human brain are similar to those that make up other primate brains. That suggests it is differences in how those cell types are combined, and in the activity of just a few hundred genes, that helps to explain the sophisticated cognitive abilities that humans have,” reported the Washington Post.
86 Billion Neurons and Glial Cells
There are about 86 billion neurons and the same number of supportive glial cells in the human brain that scientists say collectively give rise to memory, thought, emotion, and disease. Scientists know little about many “mysterious” glial cells, including Astrocytes and Microglia.
By studying the brain in such detail, scientists hope to understand more about how the brain develops, ages, and is affected by disease.
Video by StardustsQuest about the Human Brain Atlas:
Can the Brain Atlas Help Solve the Hard Problem?
Although the Human Brain Atlas reveals a great deal more about the brain at the granular level, it’s largely unknown how it all works together.
“The researchers have only a dim notion of what the newly discovered cells do,” reported the New York Times.
Thus, the brain remains mysterious, and the neurons look like the gangly figures from the Dark Crystal, don’t they? Or Ent tree creatures from the Lord of the Rings. Once you see it…
Now, we know there are thousands of unique brain cells, but what about the “Hard Problem”: consciousness?
Recently, a philosopher won a 25-year bet with a neuroscientist that there would be no answer by 2023. As with the Human Brain Atlas, millions were invested into answering the question, but the resulting hypotheses failed to fully explain consciousness.
Vastly Complex Brain Despite Entropy?
How can science hope to answer how the brain became so incredibly complex, let alone conscious? After all, science accepts that the universe tends to go toward disorder, not incredibly complex order.
This is the Law of Entropy, the second law of thermodynamics. The first law is that energy can’t be created or destroyed, although it can be transferred.
Recently, scientists from France and Canada have suggested that entropy may be why human consciousness evolved after studying nine people’s brains, seven of whom had epilepsy.
“Just like the Universe, our brains might be programmed to maximise disorder – similar to the principle of entropy – and our consciousness could simply be a side effect, the paper suggests,” reported Science Alert.
But would entropy lead to “maximizing information” through some 3,300 different types of brain cells? And given that entropy always tends to increase, wouldn’t it spell the downfall of the system or organism? Indeed, entropy seems totally at odds with the complex brain and maybe even life itself.
However, the study found measures of entropy are highest when the study participants were fully conscious rather than sleeping.
“We find a surprisingly simple result: Normal wakeful states are characterized by the greatest number of possible configurations of interactions between brain networks, representing highest entropy values,” the study states. ” Therefore, the information content is larger in the network associated to conscious states, suggesting that consciousness could be the result of an optimization of information processing.”
Wrapping Your Head Around the Brain
Can you wrap your brain around the idea that the tendency towards disorder led to complex neural network activity and consciousness? (As a ‘side-effect,’ even?) Or, is answering the Hard Problem of consciousness always going to require thinking outside the brain and material science?
Then again, can we rule out that the brain and everything we know is an artificial illusion of consciousness itself? That’s the subject of the Boltzmann Brain paradox and similar to the idea that we actually live in a simulated universe. #Matrix. Such ideas are gaining ground with some physicists and the likes of Elon Musk.
In that view, the incredibly complex simulation may not be at odds with entropy. Not if it’s all an artificial construct or one from One Supreme Consciousness if you take the spiritual view. Otherwise, a simulated matrix created by some unknown entity. But such ideas veer into the spiritual, philosophical, and metaphysical realms where science may never really hope to find all the answers. Not even with an atlas to draw from.
Video by TED-Ed about consciousness, thermodynamics, entropy, and the brain: