Immune system may target some brain synapses

A baby's brain has a lot of work to do, growing more neurons and connections. Later, a growing child's brain begins to pare down these connections until it develops into the streamlined brain of an adult.

Now researchers at the Stanford University School of Medicine have discovered the sculptor behind that paring process: the immune system.

The value of this discovery goes beyond understanding how connections are weeded out in a normal, developing brain. The finding could also help explain some neurodegenerative disorders - such as glaucoma, Alzheimer's disease and multiple sclerosis - that result from the loss of too many neuronal connections, which are known as synapses.

But according to an unknown model of the brain (see
http://en.wikipedia.org/wiki/Gaussian_adapation#the-evolution-in-the%20b...)
an algorithm such as Gaussian adaptation may - according to its theory - simultaneously maximize the mean fitness and disorder (entropy, average information) of signal patterns, thus climbing a mental landscape efficiently obeying the Hebbian rule of associative learning. This disorder and average information may be of crucial importance to the success of the process.

Exercise on the Brain

Computer programs to improve brain performance are a booming business. In the United States, consumers are expected to spend $80 million this year on brain exercise products, up from $2 million in 2005. Advertising for these products often emphasizes the claim that they are designed by scientists or based on scientific research. To be charitable, we might call them inspired by science — not to be confused with actually proven by science.

Exploring the Mind-Body Orgasm

Komisaruk: Orgasms have been described as being elicitable from any part of the body -- the mouth, the nipples, the anus, the hand. It leads us to think that there is a general orgasmic principle of building up excitation from different parts of the body leading to a climax and a resolution -- not necessarily ending in ejaculation, but a feeling of an orgasmic experience.

Whipple: We have documented in our laboratory that women can have orgasms from imagery alone without touching their body. The point is that women can experience orgasms and sexual pleasure from many forms of stimuli. It does have not have to be through genital stimulation.

WN: What are we learning about these non-genital orgasms?

Whipple: That they're real. We may have to reconsider what people define as orgasms, and not just have it defined in the genitals. We find that certain of the same brain areas are activated during orgasms experienced by imagery only (as during genital orgasms).

Komisaruk: It broadens our perspective on the potentialities of the body and brain. If we understand better how we can generate such pleasure from all different parts of our bodies, that increases our potential for sensory experience.

WN: Do you think there might come a time when orgasms really get detached from the genitals?

Komisaruk: It's happening right now. People have described orgasms through imagery, nose orgasms, knee orgasms. Although it sounds strange, the reports are believable. Now, people can show our book to someone who doubts it, and it can serve as a validation. Time will tell how prevalent non-genital orgasms are.

Komisaruk: In terms of sexuality, the holy grail is: Why does an orgasm feel so damned good? I think we're getting there.

Rewiring Neuroscience: nine-radical

In the early 1990s, our long accepted (cc 1926) understanding of how a nerve encodes and conveys information was unexpectedly overturned by experiments on fast flying bats and insects. Around 1995, we began to realize we no longer knew what neurons actually do.

This is heavily advertised by Google.

I think therefore I am, I think

But the American neuroscientist Benjamin Libet has shown that before every such movement, there is a distinctive build-up of electrical activity in the brain. And this build-up happens about half a second before your conscious ”decision” to move your arm. So by the time you think, ”OK, I’ll move my arm,” your body is halfway there. Which means your conscious experience of making a decision - the experience associated with free will - is just a kind of add-on, an after-thought that only happens once the brain has already set about its business. In other words, your brain is doing the real work, making your hands turn the pages of this magazine or reach over for your cup of tea, and all the time your conscious mind is tagging along behind.

But if this is true, the implications for our systems of morality, of crime and punishment, are shattering. We only punish those we think voluntarily did wrong - not those who literally had no choice but to act as they did. But if there is no free will, then no one has ever had a choice but to act as they did. That Eve ate the apple was as predetermined as the leaves falling to the ground in autumn. None of us could ever truly be said to be responsible for our actions. In very different ways, three new books tackle the question of whether we are free and what it means if we are not.

There is already ample evidence that prison is effectively where society sends those whose brains do not work properly. A report released last month suggested over a quarter of the UK’s almost 80,000 prison population have an IQ of lower than 80 and suspected learning disabilities, such as forms of autism and dyslexia. Another study carried out at the Young Offenders’ Institute in Aylesbury showed that if prisoners were given minerals and fatty acids essential for proper brain functioning, they committed 37 per cent fewer violent offences.