New ways of thinking how the brain works
This article is about consciousness and anesthesia. But here I excerpt some points from the article talking about new ways to think about how the brain works.
Excerpts from the article:
For much of the 20th century, neuroscientists believed that neurons performed the heavy lifting of producing conscious experience through a process called spiking, which involves transmitting a signal via an electrical impulse known as an action potential.
Spikes of neurons were seen as ones and zeros, and these were considered the carriers of information.
Scientists have realized that neuron firing isn’t solely responsible for consciousness. In fact, researchers have discovered that neurons spend about 80% of their time not spiking. During these periods, they still communicate with other brain cells through subtle electrical influences. Those influences — waves — travel around the brain 5,000 times faster than the slower signaling of synaptic spikes, and they’re being sent out all the time.
Astrocytes — star-shaped glial cells that comprise up to 40% of all cells in the brain — do more than just support neurons structurally, remove waste products, and provide nutrients. Like neurons, they also oscillate and spread electrical influences. In May, a team led by Thomas Papouin, an assistant professor of neuroscience at Washington University in St. Louis, found that a brain chemical associated with alertness, attention, and learning alters brain connectivity and function by acting on astrocytes, not neurons.
But Miller is nurturing another hypothesis that fits with the idea that brain waves, not neurons, drive consciousness: The mind actually functions more like an analog computer. These machines solve problems by representing quantities as models — think voltages or mechanical positions — rather than the ones and zeros used in digital computers.
Miller points to the human brain’s meager use of power — just 20 watts — as evidence that its computational approach must be vastly more efficient than today’s energy-hungry digital supercomputers.
In the analog brain, waves could easily serve as those models, Miller says. Computation could emerge from how waves interact, adding together or canceling out depending on their phases. And because these waves ripple across the brain’s layered, three-dimensional structure, they could support enormously complex computations.