It's probably still going to be a while before autonomous, self-aware androids are wandering amongst us. That scenario has come a little closer to reality, however, with researchers from the University of Southern California having created a functioning synapse circuit using carbon nanotubes. An artificial version of the connections that allow electrical impulses to pass between neurons in our brains, the circuit could someday be one component of a synthetic brain.
The USC Viterbi School of Engineering team was led by Professors Alice Parker and Chongwu Zhou. Parker has been looking into the feasibility of creating a synthetic brain for the past five years, as part of the BioRC Biomimetic Real-Time Cortex project.
The circuit itself consists of highly-aligned carbon nanotubes that are grown on a quartz wafer, then transferred to a silicon substrate. It mimics an actual synapse insofar as the waveforms that are sent to it, and then successfully output from it, resemble biological waveforms in shape, relative amplitudes and durations. In other words, it can take in the type of impulses generated by real neurons, and send them on in a form that could be further processed by other neurons - it can even vary the strength of those impulses, much as real synapses do in a biological process that is thought to facilitate learning.
"This is a necessary first step in the process," said Parker. "We wanted to answer the question: Can you build a circuit that would act like a neuron? The next step is even more complex. How can we build structures out of these circuits that mimic the neuron, and eventually the function of the brain?"
While Parker stated that synthetic brains are probably still decades away, she believes that the technology could ultimately be used in prosthetic nanotechnology for treating traumatic brain injuries, or for designing intelligent systems that could be used to make cars safer, among other applications.
I used to imagine that having autonomous toys would be interesting, but then I tried out a simple sphere device that would wander around on the floor. It really was autonomous, and it abruptly dawned on me that even a beloved little dog can be quite annoying at times, not to mention a child, no matter how wonderful. Instantly I realized that I did not want any autonomous anything in my house unless there were going to be a LOT of fun, help or some other benefits as a result.
I like my personal space. Dogs and children and spouses have wonderful positive effects on our lives, at least some of the time. An android? I doubt it.
No love, no comfort, therefore no android!
Beyond that, this isn\'t as exciting as it may seem. We\'ve been able to mimic neuron behavior for decades. The first artificial neuron was proposed in 1943, predating mainframes (!!). Essentially a neuron is a junction that takes an ionic impulse (the so-called electrical impulse that is in actuality a \'wave\' of opening ion gates along the axon) and chemically sums the impulses it receives both temporally (several impulses over time) and spatially (several impulses from different neurons at the same time) until a threshold value is reached. This process, as we know it now, is actually quite simple and can be expressed as a rather simple sigma equation.
What we don\'t know, and therefore this device doesn\'t do, is fully understand the role of the many disparate neuro-transmitters that our brains use. There are two primary types: GABA and glutamate which comprise over 90% of what our brains use, but there are also a myriad of other neurotransmitters that serve numerous functions (some of which can be mimicked just be adding modulation circuitry to the synapse). We don\'t yet know all the neurotransmitters in the brain, and we don\'t yet know why the brain uses many of them.
We also don\'t know how the speed of the ionic \'wave\' down the axon effects brain function (it varies on the presence of myelin sheaths and axon width), the role neural cross-talk plays in intercommunication, or how neurons form new synapses. We don\'t know if the threshold and spike value variations in neurons is a biologic byproduct or critical to brain function, and we don\'t know if the effects of any of these variables need to be simulated within an artificial neural network to generate cognizance.
A few decades or more from now. Imagine technology like this, used to transfer information between the human brain and a computer. Now slice up a small part of your brain and scan it into a computer (like the rat hypothalmus scanned into IBMs blue gene) then connect the computerized brain slice with the rest of your organic brain, and let it reintegrate itself whole again. Repeat the process till your entire organic brain has been scanned into a computer.
Scanning a brain into a computer this way means you don\'t die, you just lose tiny parts of your brain one at a time briefly. If you just destroyed and scanned your brain in one go you\'d be making a digital copy of yourself and killing the original. And brain scanning likely involves brain destruction in the foreseeable future. So what I described instead is a way of scanning your brain into a computer without dieing.
The science fiction of today sometimes becomes the science fact of tomorrow.