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Whedonesque - a community weblog about Joss Whedon
"But you, Rosenberg...you REALLY got under my skin."
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October 15 2009

Is real science catching up to Topher ? New Scientist reports that a Laser has been used to create false memories in fly brains.

"A flash of laser light can alter the brains of fruit flies so that they learn to fear pain that they never actually felt".

OK so Topher probably doesn't have too much to worry about just yet, except maybe a guest appearance by Jeff Goldblum, but does anyone else find it amazing that even such a tiny amount of brain alteration is actually possible ?

I saw a TED talk last week where a researcher said that it is possible to slightly change people's moral judgments with targeted electromagnetic pulses. She also showed a video demonstrating that the same technique could be used to cause involuntary movements, in this case of her own hand.
I always wonder, when reading an article like this, just what the genesis of the hypothesis in the scientist's mind must have been like. How does it occur to one to start zapping flies? Maybe he was vomited on as a child?
I thought the article explained how they ended up using light to trigger the response pretty well. No vomit needed, just a few observations, tinkering, a new "what if," and off we go. This is a good example of how these experiments develop.

"It would be unethical to engineer transgenic humans and tell them what memories to have"

True but the conversations between you and your engineered person would make great tv.

My sweater is itchy.
Not to mention now being able to drive a van using your iPhone, just like Dr. Horrible. (Didn't think of the connection myself, saw it referenced that way on Twitter.)
Mercenary: Electric shock as an aversive stimulus has been standard in psychology and animal behavior experiments for decades. So anyone who thinks about studying avoidance will more or less immediately think of shcok.
Old Scientist reports the creation of false memories in humans using minute quantities of alcohol.
I'm a little fuzzy on this but I sort of imagined that being zapped by a laser (in/to your brain at that) would possibly also result in some sort of pain they might be adverse to?

Like how I hate morons in stadiums or other 360 degree venues that bring laser pointers.
Now for my intelligent question.. Why is 'Laser' capitalized in the post?
Old Scientist reports the creation of false memories in humans using minute quantities of alcohol.

The passage of time works pretty well for that, too.
Mail-Order Scientist reports the altering of brain patterns by baseball bat. There're concerns about repeatability though.

Nice experiment that, i'm not totally convinced the conclusion's justified quite yet (i'm with the guy who says they didn't show what was happening to those particular neurons in the "genuine learning" situation with real electric shocks) but it seems fairly safe to assume that, since memories are at some level biochemical then if you can alter the biochemistry with sufficient precision you can create memories.

The problem with the dollhouse tech in real-life was never that we can't create artificial memories it was always (to me) more about reading (and then writing) an entire brain state.
It’s the discovery of a mechanism that can trigger individual neurons using light that makes this curious w/r/t Dollhouse, and not so much that manipulating neurons – which they have been able to do for years – can trigger memories and behaviour. This technique is just a tool in the quest of mapping and understanding the complete brain of a model species, but it is a very interesting one nonetheless.

Extrapolating the future, it’s not inconceivable to me that it’ll be possible to alter and meter most parts of the brain. But to do it in the time and with the ease with which it’s done in the series seems pretty damn far off. I’ve never thought about the altering process as physically changing the target brain into a perfect copy of the source brain. That would approach impossibility. Instead, what seems more reasonable is transforming the source unto the underlying ‘hardware’ of the target brain, so to speak. How to calculate that transform is possibly a harder problem to solve than the biochemistry bit.
My animation seminar professor always refers to science fiction as "the history of the future" in reference to inspiration some scientists actually do glean from technology depicted therein. The brain is a complex and still little-understood organ compared to its full potential, but who knows? Someday perhaps we will have capabilities to match what is depicted on Dollhouse... dun dun dunnn.
Instead, what seems more reasonable is transforming the source unto the underlying ‘hardware’ of the target brain, so to speak. How to calculate that transform is possibly a harder problem to solve than the biochemistry bit.

Not really sure what you mean by "transform" hence. Do you mean altering the copy of the personality so that when you "play it back" on the active's brain it behaves as if it's the original copy (despite the different brain structure and chemistry) ? So where the original would have stimulus A -> brain state X, the copy might have stimulus A -> black box transformation -> brain state X (because the copy's actual brain state due to stimulus A would, without the transform, have been Z) ?

Interesting idea that (if that's what you mean). As you say though, the transform would be very hard in practice and maybe even impossible in principle since it would seem to require knowledge of ALL possible brain states (and their accompanying stimuli) and how to get from one to another. It also depends on stimulus A always yielding brain state X (or at least on the resulting brain state being reachable from X in a consistent, deterministic manner) which might hold true in drosophila but may well not in a species that's aware (to some extent) of its own brain states and how they might relate to stimuli.

As to whether the brain state is read/writeable at all, I think it comes down to the level of detail required. To me, for a complete consciousness copy which is exact in every way (as with e.g. the copy of Margaret) you'd need to record the brain state (position of neurons, concentration of neurotransmitters, blood flow etc.) right down to the quantum level which Heisenberg's uncertainty principle tells us just isn't doable.

(and the laser stuff's cool but presumably it's not going to work on us because only a very small proportion of our neurons are exposed to light ?)
Do you mean altering the copy of the personality so that when you "play it back" on the active's brain it behaves as if it's the original copy (despite the different brain structure and chemistry) ?

Yes, precisely. In the spirit of wild speculation it at least sounds more plausible to me :) It would still require modifying the response function of individual neurons, but compared to the scenario of making a perfect ‘molecular’ copy, where you’d have to grow new dendrites and whatnot, it’s not quite as far-fetched. It may also solve the problem of measuring and modifying with the precision you were talking about. As long as a group of neurons behave sufficiently close to how the corresponding group behaves in the source brain, things might work out and the individual neurons wouldn’t have to be exact copies. A neural net computes, or approximates, functions. So the problem is reduced to modifying an existing net to compute the same function as another net that is topologically different.

A neat side effect of looking at it like that is that it fits the metaphor of acting a bit better, maybe.

(and the laser stuff's cool but presumably it's not going to work on us because only a very small proportion of our neurons are exposed to light ?)

Would have to be awfully strong light to penetrate our thick brainpans.
We're all doomed.
Would have to be awfully strong light to penetrate our thick brainpans.

Or awfully long light ;), thinking about Salocin's EM pulses (probably too imprecise though).

Yeah hence, I like the fit with the acting metaphor, different actors could be said to have some segments of their neural net in closer approximation to the "original" performance than others for instance.

Re: approximations though, to me that's unlikely to lead to a good copy (in the sense of being accurate enough to seem to be the same person to outsiders, let alone to the person themselves). Just seems like the less precise the copy the more quickly it'll diverge from the original. Guess it depends on how resistant to perturbations our brains normally are though (if they're normally kind of "close-ish is good enough" when it comes to results then a close-ish copy might do).

(but I definitely agree it's more plausible since, as I say, i'm not convinced an exact copy is possible even in principle)

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