Bandwidth of your brain

How much bandwidth does it take to run a completely convincing virtual environment for one person? The answer is surprisingly small. In Consciousness Explained, Dennett claims that an "interactive smello-feelo television would have an astronomical bandwidth" (6); he didn't bother to estimate how astronomical. If you've ever studied physics, you'd be familiar with this kind of estimation: a Fermi problem. Let's play:

A Blu-ray disk outputs a maximum of 40 Mbit/s; it's the best quality video for the general consumer, and it's just about as good as our eyes can see. Blu-ray has surround-sound audio too, so the 40 Mbit/s covers two of our senses: sight and hearing.

Smell and taste are both slower and less sensitive than hearing, and way less than vision. We can distinguish something that's flashing once per second from something that's flashing once per half second. We can easily tell when a musician switches from one time signature to another. But have you ever smelled something that pulsates every second? 10 Mbit/s should cover both smell and taste, and that's being generous.

Proprioception is even simpler. The body has 200ish bones and a similar number of joints. At each moment we are aware of the angle of each of those joints. We are also aware of how tense each of  those skeletal muscles are. A virtuoso piano player can hit about 20 notes per second, and she must know exactly where her fingers are; that gives 20*200*16 = 64 kbit/s, with the 16 bits encoding the angle.

That just leaves touch: pressure, pain, and heat. Skin is the biggest sensory organ in the body, but is it more sensitive than sight? We can feel tiny vibrations and locate pressure with pin-prick precision, especially near our hands and lips. I think 50 Mbit/s would suffice for the entire body (including those extra sensitive parts :)

What about output? The only interesting way of sending information is through our muscles. Yes, I'm going to exclude any excretion of bodily fluids. We have 600ish skeletal muscles which can be moved at about 20 times per second, with varying levels of contraction. That's only about 1 Mbit/s. It's not surprising that our sensory input is 100 times greater than output. You'll probably find the same ratio if you look at your computer's network usage.

So that adds up to about 100 Mbit/s, give or take a factor of 10. In comparison, the current wireless LAN protocol (802.11n) has a max data rate of 600 Mbit/s: more than enough to saturate every one of our senses. All we need is a modem to convert digital signal to the right impulses, and splice it into our nerves.

 Yes, you can kick ass in the Matrix through an 802.11n wireless network.

What about Dennett's other objection, that interactive simulations will take more bandwidth? That is actually a mistake; I have already covered all the input and output channels of a human brain, and analyzed the total bandwidth. Interactivity with the environment is a result of the laws of physics: gravity, thermodynamics, light, solids and liquids, etc. Calculating the result of you throwing a rock into a pond will not demand any more bandwidth; this simulation only requires processing power. Today, we have graphics chips (from nVidia and ATI)  that can produce real-time, nearly realistic rendering of scenes; these chips use specialized circuits to compute the way light interacts with matter. Those same companies are also making specialized physics chips that can simulate how pieces of matter interact with each other.

What's the hold-up then? Why aren't we hooking our brains up to virtual worlds yet?

Oh, right.

The Dating Algorithm

Dating, or pursuing a relationship, is an example of a stochastic search with simulated annealing algorithm. You work on improving your relationship, but sometimes you get stuck in a rut, in a local optimum. There might be new and wonderful experiences out there, but you can't see past what's in front of you. So, once in a small probability, you shake things up and take a risk. You try something new: different person, different place, different activity. The probability, related to the "temperature" parameter, decreases as you get older, until finally you stop taking those risks and settle down to that life, for better or worse.

(Note to self: I should make an animation of this algorithm.)

This post is a sneak peek at the next part of the hedonism series: Relationship engineering.

Soma madness!

Let's imagine the perfect drug.

(This is part 2 of the hedonism series. Put your party hats on!)

First, it shouldn't have any unwanted side effects. No physical impairment (drunk), no addiction or physical dependence (heroin), no long term impact on your body (cancer from smoking), no bad trips, no risk of overdose, no withdrawal symptoms, no buildup of tolerance.

Thanks to advances in biochemistry, we know why these side effects occur. For example, a chemical called dynorphin blocks the reward pathway in your brain, inhibiting you from feeling the same pleasure over and over. If you use cocaine repeatedly, your brain makes more dynorphin and you won't get the same high you got when you started. Addiction is more complicated, but there's no reason why we can't figure out a cure.

So the perfect drug has no nasty side effects, but what can it do for you?

The pleasure drugs: These are the ones that directly stimulate the reward centers of your brain: new forms of heroin, oxycotin, morphine, drugs that wash away pain and turns your pleasure dial up beyond what is natural. It doesn't have to be a chemical substance either; scientists have successfully hooked up electrode to the spinal nerve of disabled patients and use it to trigger orgasms. If possible, electrical brain stimulation (wireheading) may provide a safer and cleaner high than chemicals.

But getting high is boring, one-dimensional. It's a solitary and selfish experience; you can't share it with other people in any meaningful way. Press a button, take a dose, and you'll be checking out of reality, floating through outer space, alone. There's not much else you can do when the intense artificial pleasure eclipses all other feelings. What might that do to your psyche? Look:

A portrait of loneliness: Kurt Cobain spent his last years struggling with heroin addiction; this was him on a good day.

The mood drugs: These drugs affect you in subtler, but more diverse ways. Unlike the pleasure pills, you'll stay grounded in reality, but your mood, personality and motivations are shifted in the designed direction.

Shown here in a common delivery device, caffeine is the second most popular drug in the world.

They can make a depressed person happier (Zoloft, Prozac), calm your anxieties and ease your stress;  they can make you friendlier (Ecstasy), more open and empathic, lower your inhibitions (alcohol); they can make you more motivated, focused (Ritalin, Adderall), raise your alertness (caffeine); they can make you feel safer and more secure, more trustful (oxytocin), increase your libido (testosterone), and even make you fall in love.

Yes, love; read the wireheading article and take note: "Repetition of these stimulations made the patient more communicative and flirtatious, and she ended by openly expressing her desire to marry the therapist." Dr. Paul Zak has also found link between the chemical oxytocin and feelings of social trust and attachment to lovers, to friends, to children, to God.

So you can become fitter, happier, more productive, comfortable, but is there an upper limit? That's what David Pearce asks, and he postulates a future where our level of well-being far exceeds what we feel today, a sublime happiness. What that would be like I can barely imagine. But I know that in the future, "not in the mood" will no longer be a hindrance; I can be in the mood, any mood, as long as I want to. That's freedom of self-expression.

But mood drugs are imprecise; they depend on the action of chemicals like serotonin that paints a broad spectrum of effects. It won't engage any higher-level mental concepts, only your gut-feelings. No wistful reminiscence, no bittersweet goodbyes, no victorious thrills. Though these drugs can prime you to enjoy living, you still have to go outside and actually do it. That brings us to the third kind...

The sensory drugs: These can make what you do feel better by enhancing and distorting your senses. In addition to their positive effects on mood, MDMA (Ecstasy) and methaqualone (quaaludes) can enhance your sensations of touch, making sex more pleasurable and intense. Mushrooms , mescaline, LSD, and other hallucinogens can change your perception in profound ways. Some color-blind people have even reported being able to see color while under the effects of LSD.

Depiction of the very first LSD trip: chemist Albert Hofmann biked home after taking ten times the regular dose.

So imagine that special occasion when you want the food and wine to taste a bit more delicious, the lights and the smile to look more vivid, the touch and the kiss to be more sensual, and everything basking in the soft glow of a heightened appreciation for reality. Think of a dance party, the music, the rhythm and movement. Think of running or swimming or biking and the incredible sense of freedom and speed you can get from just normal, everyday activities. You won't have to jump off mountains get that thrill!

You may have noticed that I've skipped over something between getting in the right mood and experiencing enhanced sensations. In this giant gap of the story is where we actually live our lives, where we work and learn and play. In here lies the difference between the false utopia of Brave New World, and the rich, varied, and fulfilling future you and I want to live in. And that's where I'll explore in the next part of Hedonism for the Transhuman.

Random thoughts and links:

• You know what I want? A reset button: something that can roll back your brain to a saved state. That way I can satisfy my curiosity on whatever I wish to try without worrying about any adverse and unforeseen effects. I get to keep all memories, but my emotional outlook, preferences, and goals can be safeguarded against unforeseen consequences. It's pure fantasy though.
  
  
• There's a major obstacle to what kind of chemicals we can put into our brains: the blood-brain barrier. It stops most cells, bacteria and large chemical molecules from entering the brain.
  
  
• Erowid.org has a comprehensive collection of facts, advice, and anecdotes about drug use.
  
  
• Neuroscientist Anjan Chatterjee has raised some ethical concerns about the future of pharmacological enhancements. I'll have to think about some of his objections to a drug-fueled society.

Transhumanist hedonism: or, let's party like it's 2099.

What's the point of living longer if you're not having any fun? I wouldn't want to do the same old same old for another 40 years, let alone for the kind of lifespan that de Grey envisions. So, How do we extend the range and depth of the human experience? According to sci-fi canon, futuristic recreation will come along the big three: drugs, sex, and videogames.

But lets go back to the original mythology for a moment: what is heaven like? Not the afterlife that's held out as a reward for the religious faithful; I'm talking about the general concept of an ideal, perfect existence. Transcendental well-being, without bounds.

It seems to me that the traditional Christian version of Heaven is not nearly as well-depicted as the Christian Hell, the fire and brimstone. I can easily imagine an eternity of suffering, but what is the opposite of that? Is it just an eternity of happiness with your family and loved ones?

Don't get me started on the whole 72 virgins thing for Islam; what happens when you run out of virgins?? (Most people don't believe this anyway, like the Christian imagery of clouds and angels and harps.)

A perpetual drug-like high, the kind that's induced by opium or heroin? Everlasting orgasm?

Pure blissful happiness, forever? Wouldn't that get boring? 
 


Here, Picard and Kirk are stuck in the Nexus, which makes real all their dreams and desires. The best starship captain in the galaxy only wants a fancy Christmas dinner with well-dressed children and a carousel? Chopping wood by a mountain cabin? Please. Besides, any place that you wish to leave is inadequate as heaven.

Maybe heaven is conflict? Drama and adventure, battles and challenges, pain and sacrifice, love and loss, defending the galaxy, thrilling in victory, forever striving and achieving?

What do you want in your personal heaven?

Famed transhumanist David Pearce proposes to bring about heaven on Earth using technology, what he calls paradise engineering. First eliminate pain and suffering, then boost our baseline sense of well-being. The possible methods: designer drugs, wireheading, genetic engineering.

It's a noble goal, but like our visions of heaven, it is one-dimensional and incomplete. Transhumanism should aim to expand the scope of human experience, and that does not simply stop at happiness.

So what else is a hedonist to do? Stay tuned!