Welcome to the Connectome

Diffusion spectrum image shows brain wiring in a healthy human adult. The thread-like structures are nerve bundles, each containing hundreds of thousands of nerve fibers. Source: Source: Van J. Wedeen, M.D., MGH/Harvard U. To learn more about the government's new connectome project, click on the brain.

Diffusion spectrum image shows brain wiring in a healthy human adult. The thread-like structures are nerve bundles, each containing hundreds of thousands of nerve fibers.
Source: Source: Van J. Wedeen, M.D., MGH/Harvard U. To learn more about the government’s new connectome project, click on the brain.

You may recall recent coverage of a major White House initiative: mapping the brain. In that statement, there is ambiguity. Do we mean the brain as a body part, or do we mean the brain as the place where the mind resides? Mapping the genome–the sequence of the four types of molecules (nucleotides) that compose your DNA–is so far along that it will soon be possible, for a very reasonable price, to purchase your personal genome pattern.

A connectome is, in the words of the brilliantly clear writer and MIT scientist, Sebastian Seung, is: “the totality of connections between the neurons in [your] nervous system.” Of course, “unlike your genome, which is fixed from the moment of conception, your connectome changes throughout your life. Neurons adjust…their connections (to one another) by strengthening or weakening them. Neurons reconnect by creating and eliminating synapses, and they rewire by growing and retracting branches. Finally, entirely new neurons are created and existing ones are eliminated, through regeneration.”

In other words, the key to who we are is not located in the genome, but instead, in the connections between our brain cells–and those connections are changing all the time.The brain, and, by extension, the mind, is dynamic, constantly evolving based upon both personal need and stimuli.

Connectome BookWith his new book, the author proposes a new field of science for the study of the connectome, the ways in which the brain behaves, and the ways in which we might change the way it behaves in new ways. It isn’t every day that I read a book in which the author proposes a new field of scientific endeavor, and, to be honest, it isn’t every day that I read a book about anything that draws me back into reading even when my eyes (and mind) are too tired to continue. “Connectome” is one of those books that is so provocative, so inherently interesting, so well-written, that I’ve now recommended it to a great many people (and now, to you as well).

Seung is at his best when exploring the space between brain and mind, the overlap between how the brain works and how thinking is made possible. For example, he describes how the idea of Jennifer Aniston, a job that is done not by one neuron, but by a group of them, each recognizing a specific aspect of what makes Jennifer Jennifer. Blue eyes. Blonde hair. Angular chin. Add enough details and the descriptors point to one specific person. The neurons put the puzzle together and trigger a response in the brain (and the mind). What’s more, you need not see Jennifer Aniston. You need only think about her and the neurons respond. And the connection between these various neurons is strengthened, ready for the next Jennifer thought. The more you think about Jennifer Aniston, the more you think about Jennifer Aniston.

From here, it’s a reasonable jump to the question of memory. As Seung describes the process, it’s a matter of strong neural connections becoming even stronger through additional associations (Jennifer and Brad Pitt, for example), repetition (in all of those tabloids?), and ordering (memory is aided by placing, for example, the letters of the alphabet in order). No big revelations here–that’s how we all thought it worked–but Seung describes the ways in which scientists can now measure the relative power (the “spike”) of the strongest impulses. Much of this comes down to the image resolution finally available to long-suffering scientists who had the theories but not the tools necessary for confirmation or further exploration.

Next stop: learning. Here, Seung focuses on the random impulses first experienced by the neurons, and then, through a combination of repetition of patterns (for example), a bird song emerges. Not quickly, nor easily, but as a result of (in the case of the male zebra finches he describes in an elaborate example) of tens of thousands of attempts, the song emerges and can then be repeated because the neurons are, in essence, properly aligned. Human learning has its rote components, too, but our need for complexity is greater, and so, the connectome and its network of connections is far more sophisticated, and measured in far greater quantities, than those of a zebra finch. In both cases, the concept of a chain of neural responses is the key.

Watch the author deliver his 2010 TED Talk.

Watch the author deliver his 2010 TED Talk.

From here, the book becomes more appealing, perhaps, to fans of certain science fiction genres. Seung becomes fascinated with the implications of cryonics, or the freezing of a brain for later use. Here, he covers some of the territory familiar from Ray Kurzweil’s “How to Create a Mind” (recently, a topic of an article here). The topic of fascination: 0nce we understand the brain and its electrical patterns, is it possible to save those patterns of impulses in some digital device for subsequent sharing and/or retrieval? I found myself less taken with this theoretical exploration than the heart and soul of, well, the brain and mind that Seung explains so well. Still, this is what we’re all wondering: at what point does human brain power and computing brain power converge? And when they do, how much control will we (as opposed to, say Amazon or Google) exert over the future of what we think, what’s important enough to save, and what we hope to accomplish.

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Secrets of Memory – Exposed!

I just received a piece of plastic, about the size of a postage stamp, containing as much memory as a MacBook Air: 64GB. And that made me wonder: is the 64GB on the Monster Digital SD XC USH-1 Class 10 Vault Series card (got all that?) the same as the  64GB of flash memory inside the Air?

Well, no, it’s not. Not according to Mike Ridling and Mark Morrissey, the President and Head of Storage Technology at Monster Digital.

We started at the beginning: spinning disks. Over the decades, the disks became smaller, and when Apple used the technology in the iPod, 1 in 3 units failed. So, Apple went shopping for a better solution.

At the time, flash drives had been around for about five years, and they were popular, but limited in terms of storage capacity. Camera manufacturers were experimenting with ways to store large number of images in a non-volatile format (that is, when the power goes off, the stored material remains). Then, Apple adopted flash memory for their portable devices–and the market shifted from spinning disks to non-volatile, highly portable, small-sized memory.

What’s inside that SD card? A tiny controller that routes data into and out of the card, and organizes the data on the card’s silicon chip so that it’s accessible and so that the card lasts as long as possible (but not forever).

About six years ago, the Secure Digital Association (SD = Secure Data) standardized the metrics for both memory capacity (64GB) and access speed (Class 10). In fact, the access speed matters–but the information is not always easy to find in your device’s instructions. If you own a big DSLR, buy Class 10 cards. Ditto for any camcorder that costs more than, say, $600-700. A Class 6 card is sufficient for a lesser camcorder or a more modest digital still camera. If you’re using the card in a smart phone or a low resolution camera (say, 2-3 megapixels), then a Class 2 is all you need. Of course, Class 10 cards cost more than Class 2 cards.

If you require higher transfer rates, you’ll want a UHS-1 compatible card, but note that not all of these cards are compatible with all devices. (Monster emphasized that their card works with a lot of different devices.)

Right now, the largest available SD cards are 128GB, but we’ll see 256GB in a year or so. Somehow, through the miracle of engineering, the cards are able to store more data but they don’t become larger (more data is stored within the available space). This means we can expect compatibility for a longer period of years.

Now what about the 64GB SD card in the 64GB MacBook Air? Can I simply double my storage capacity with the purchase of a $200 memory card? Well, sort of. The SATA3 solid state drive in the MacBook Air transfers data at 6GB per second. How does the SD card compare? Well, it’s slower. A lot slower: 80MB per second. This is why the SD card is better suited to, say, storing documents and transferring documents on the Air than, say, running Photoshop. In fact, the 64GB and it’s big sister, the 128GB are ideal for storing either almost 25,000 photographs, nearly 11 hours of HD video, over 1,000 hours of digital music. It’s ideal for use in an HD video camera, for example.

I did ask about whether technology was changing quickly enough to affect my thinking about the next generation Air (coming in May, we think). The answer came as something of a surprise: a new external drive for the Air (and other devices) that would plug into the new Thunderbolt port. Offering a transfer rate of about 10GB per second (1/6 of the internal drive, but a heck of a lot faster than the SD card), this is probably the next step in portable memory for portable computers.

And what about iPad storage? Yeah, it’s kinda messy. Apple really didn’t design iPads for external storage, so the solutions are workarounds. That probably won’t change in the future.

So, I’ve learned to use terms such as “transfer rate” and “Class 10” with some knowledge that I lacked yesterday. And, I’ve gotta say, I have a soft spot for Monster. So, thanks to the two executives who helped me to navigate this technology.

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