http://medicalxpress.com/news/2013-10-neuroscientists-mini-neural-brain.html

Dendrites, the branch-like projections of neurons, were once thought to be 
> passive wiring in the brain. But now researchers at the University of North 
> Carolina at Chapel Hill have shown that these dendrites do more than relay 
> information from one neuron to the next. They actively process information, 
> multiplying the brain's computing power.
>
> "Suddenly, it's as if the processing power of the brain is much greater 
> than we had originally thought," said Spencer Smith, PhD, an assistant 
> professor in the UNC School of Medicine.
>
> His team's findings, published October 27 in the journal Nature, could 
> change the way scientists think about long-standing scientific models of 
> how neural circuitry functions in the brain, while also helping researchers 
> better understand neurological disorders.
>
> "Imagine you're reverse engineering a piece of alien technology, and what 
> you thought was simple wiring turns out to be transistors that compute 
> information," Smith said. "That's what this finding is like. The 
> implications are exciting to think about."
>
> Axons are where neurons conventionally generate electrical spikes, but 
> many of the same molecules that support axonal spikes are also present in 
> the dendrites. Previous research using dissected brain tissue had 
> demonstrated that dendrites can use those molecules to generate electrical 
> spikes themselves, but it was unclear whether normal brain activity 
> involved those dendritic spikes. For example, could dendritic spikes be 
> involved in how we see?
>
> The answer, Smith's team found, is yes. Dendrites effectively act as 
> mini-neural computers, actively processing neuronal input signals 
> themselves.
>
> Directly demonstrating this required a series of intricate experiments 
> that took years and spanned two continents, beginning in senior author 
> Michael Hausser's lab at University College London, and being completed 
> after Smith and Ikuko Smith, PhD, DVM, set up their own lab at the 
> University of North Carolina. They used patch-clamp electrophysiology to 
> attach a microscopic glass pipette electrode, filled with a physiological 
> solution, to a neuronal dendrite in the brain of a mouse. The idea was to 
> directly "listen" in on the electrical signaling process.
>
> "Attaching the pipette to a dendrite is tremendously technically 
> challenging," Smith said. "You can't approach the dendrite from any 
> direction. And you can't see the dendrite. So you have to do this blind. 
> It's like fishing if all you can see is the electrical trace of a fish." 
> And you can't use bait. "You just go for it and see if you can hit a 
> dendrite," he said. "Most of the time you can't."
>
> Once the pipette was attached to a dendrite, Smith's team took electrical 
> recordings from individual dendrites within the brains of anesthetized and 
> awake mice. As the mice viewed visual stimuli on a computer screen, the 
> researchers saw an unusual pattern of electrical signals – bursts of spikes 
> – in the dendrite.
>
> Smith's team then found that the dendritic spikes occurred selectively, 
> depending on the visual stimulus, indicating that the dendrites processed 
> information about what the animal was seeing.
>
> To provide visual evidence of their finding, Smith's team filled neurons 
> with calcium dye, which provided an optical readout of spiking. This 
> revealed that dendrites fired spikes while other parts of the neuron did 
> not, meaning that the spikes were the result of local processing within the 
> dendrites.
>
> Study co-author Tiago Branco, PhD, created a biophysical, mathematical 
> model of neurons and found that known mechanisms could support the 
> dendritic spiking recorded electrically, further validating the 
> interpretation of the data.
>
> "All the data pointed to the same conclusion," Smith said. "The dendrites 
> are not passive integrators of sensory-driven input; they seem to be a 
> computational unit as well."
>
> His team plans to explore what this newly discovered dendritic role may 
> play in brain circuitry and particularly in conditions like Timothy 
> syndrome, in which the integration of dendritic signals may go awry.
>


"*This revealed that dendrites fired spikes while other parts of the neuron 
did not, meaning that the spikes were the result of local processing within 
the dendrites.*"

Yep, looks like neurons have a nervous system of their own now. Still think 
that consciousness is a product of the brain?

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