Clipmarks | pokkets's 'brain' clips

Chance discovery sheds light on S.I.D.S.

Fri, 04 Jul 2008 04:19:26 GMT

clipped by: pokkets
clipper's remarks: Cot death, or Sudden Infant Death Syndrome has been a mystery, and a number of causes have studied. It has also been suggested that there may be more than one cause. While the study was on mice, they hope it will lead to more clues in the search for causes in humans, and help identify babies at risk

Clip Source: www.abc.net.au

An imbalance of a key brain chemical could be the cause of cot death, after a chance discovery by researchers in Italy.

The team, based at the European Molecular Biology Laboratory, found that an out of balance self-regulating system controlling the nerve-signalling chemical serotonin in the brainstem, caused sudden death in mice.

Writing in the journal Science, they hope their experiment will help doctors pinpoint human babies at high risk of cot death, also known as Sudden Infant Death Syndrome (SIDS).

While the researchers say it is unlikely the molecular mechanism is the same in humans, they believe their findings may one day help identify babies at greatest risk.

"Ultimately, we hope it will give new ideas to doctors about how to diagnose babies at risk for SIDS," says Dr Enrica Audero

Genetically engineered mice whose self-regulating serotonin system was turned off did not die, showing it was worse to have a malfunctioning system than no system at all, the study says.

10 Important Differences Between Brains and Computers

Tue, 01 Jul 2008 10:34:22 GMT

clipped by: wildcat

Clip Source: scienceblogs.com

Although the brain-computer metaphor has served cognitive psychology well, research in cognitive neuroscience has revealed many important differences between brains and computers. Appreciating these differences may be crucial to understanding the mechanisms of neural information processing, and ultimately for the creation of artificial intelligence. Below, I review the most important of these differences (and the consequences to cognitive psychology of failing to recognize them): similar ground is covered in this excellent (though lengthy) lecture.

Difference # 1: Brains are analogue; computers are digital

Difference # 2: The brain uses content-addressable memory

Difference # 3: The brain is a massively parallel machine; computers are modular and serial

Difference # 4: Processing speed is not fixed in the brain; there is no system clock

Difference # 5 - Short-term memory is not like RAM

Difference # 6: No hardware/software distinction can be made with respect to the brain or mind

Tags: computers, brains, metaphors

Good cholesterol may protect memory

Tue, 01 Jul 2008 10:28:30 GMT

clipped by: pokkets
clipper's remarks: There is good and bad cholesterol. They sum it up by saying, what is good for the heart, is good for the brain.
Certain changes in lifestyle can have a positive impact on raising HDL levels:
Aerobic exercise, Weight loss, Smoking cessation.
Removing trans fatty acids from the diet
One to two drinks of alcohol a day - HDL transports cholesterol to the liver and cholesterol is known to have a protective effect on the cell membrane. It is likely that this reflects the liver's need for more cholesterol to protect itself from the alcohol. Adding monounsaturated and polyunsaturated fats to the diet, and reducing or eliminating saturated fats. Adding soluble fiber to diet. Oats are a prime source. Taking Omega 3 fatty acids such as in tuna, or sardines, or suppliments. Limiting intake of dietary fat to 30–35% of total calories
Taking Niacin aka Vitamin B3

Clip Source: www.abc.net.au

Low levels of so-called good cholesterol during middle age may increase the risk of memory loss and dementia, European researchers say.

The study, involving about 3700 British men and women, was published in the American Heart Association's journal Arteriosclerosis, Thrombosis and Vascular Biology.

It found that low levels of high-density lipoprotein, or HDL, cholesterol were linked to declining memory by age 61.

Experts predict increasing numbers of people worldwide will develop Alzheimer's in the coming decades as populations in many countries grow older.

Scientists are trying to identify risk factors that may appear years before the onset of dementia to help find ways to prevent or postpone it.

"Considering the way the population is ageing - the 65-plus age group being the fastest-growing age group - we are facing a dementia time bomb," says Dr Archana Singh-Manoux of the French National Institute for Health and Medical Research and the University College London

“What is Life?” Evolution of Robots is Causing Scientists to Question

Tue, 01 Jul 2008 10:04:36 GMT

clipped by: wildcat
clipper's remarks: “Robots are not human, but humans aren’t the only things that have emotions,” she said. “The question for robots is not, Will they ever have human emotions? Dogs don’t have human emotions, either, but we all agree they have genuine emotions. The question is, what are the emotions that are genuine for the robot?”

Clip Source: www.dailygalaxy.com

There is ongoing debate about what constitutes life. Synthetic bacteria for example, are created by man and yet also alive. Some go so far as to say that robot “emotions” may already have occurred—that current robots have not only displayed emotions, but in some ways have experienced them.

“We’re all machines,” says Rodney Brooks author of “Flesh and Machines,” and former director of M.I.T.’s Computer Science and Artificial Intelligence Laboratory, “Robots are made of different sorts of components than we are — we are made of biomaterials; they are silicon and steel — but in principle, even human emotions are mechanistic.” A robot’s level of a feeling like sadness could be set as a number in computer code, he said. But isn’t a human’s level of sadness basically a number, too, just a number of the amounts of various neurochemicals circulating in the brain? Why should a robot’s numbers be any less authentic than a human’s?

Tags: robotics, intelligence, life

Mechanism and function of humor identified by new evolutionary theory

Mon, 30 Jun 2008 21:24:01 GMT

clipped by: Mohir
clipper's remarks: "By removing stipulations of content we have been forced to study the structures underlying any instance of humour, and it has become clear that it is not the content of the stimulus but the patterns underlying it that provide the potential for sources of humour. For patterns to exist it is necessary to have some form of content, but once that content exists, it is the level of the pattern at which humour operates and for which it delivers its rewards."

Previous theories have only ever applied to a small proportion of all instances of humour, many of them stipulating necessary content or social conditions either in the humour itself or around the individual experiencing it. But this doesn't explain why an individual can laugh at something when no one else around them does, nor why two people can laugh at the same stimulus for different reasons.

Clip Source: www.physorg.com

A new publication answers centuries' old questions regarding the mechanism and function of humour, identifying the reason humour is common to all human societies, its fundamental role in the evolution of homo sapiens and its continuing importance in the cognitive development of infants.

"The theory is an evolutionary and cognitive explanation of how and why any individual finds anything funny. Effectively it explains that humour occurs when the brain recognizes a pattern that surprises it, and that recognition of this sort is rewarded with the experience of the humorous response, an element of which is broadcast as laughter.

Tags: humor, evolution

Magnet puts tongue in the drivers seat

Mon, 30 Jun 2008 07:27:26 GMT

clipped by: pokkets
clipper's remarks: The nerve in the tongue is directly connected to the brain, and is one of the things that is least likely to be damaged in spinal cord injuries.
Considering the way people can talk, it is likely to be as, or more maneuverable than the hands.
The phrase 'Actions speak louder than words' could take on a whole new meaning.

Clip Source: www.abc.net.au

Maggie Fox

US researchers have developed a device that uses a tiny magnet that can help disabled people become more independent using just the tip of their tongue.

The magnet, the size of a grain of rice, is implanted under the tongue and lets the user direct the movement of a cursor across a computer screen or a powered wheelchair around a room.

The team from Georgia Institute of Technology reported on their device to a meeting of the Rehabilitation Engineering and Assistive Technology Society of North America in Washington DC.

"We chose the tongue to operate the system because unlike hands and feet, which are controlled by the brain through the spinal cord, the tongue is directly connected to the brain by a cranial nerve that generally escapes damage in severe spinal cord injuries or neuromuscular diseases," says Professor Maysam Ghovanloo, who helped direct the work.

"Tongue movements are also fast, accurate and do not require much thinking, concentration or effort."

Targeting epilepsy at the source

Wed, 25 Jun 2008 08:50:23 GMT

clipped by: pokkets

Clip Source: www.abc.net.au

Dani Cooper

People who suffer epileptic seizures could be treated using drug-infused polymer implants in their brain, according to an Australian researcher.

Speaking at the Asia-Pacific Symposium on Nanobionics in Wollongong this week, Professor Mark Cook, of St Vincent's Hospital in Melbourne, says tests on rats shows the polymer implants reduce the frequency, length and severity of seizures.

Cook, who is also attached to the University of Melbourne's Department of Neurology, says by delivering drugs close to the source of the seizure in the brain the amount of drug used is reduced and side effects are therefore kept to a minimum.

Cook told the conference that epilepsy is the second-most common neurological illness with 1% of sufferers having recurrent seizures.

But he says, the toxicity and dose levels of most epilepsy drugs creates major issues for users, with 31% of patients reporting adverse side effects from the drugs, with50% of those being clinically significant.

Technology unlocks the silent mind

Thu, 19 Jun 2008 03:47:08 GMT

clipped by: pokkets
clipper's remarks: They can detect the answer to a yes/no question, from the scans of healthy volunteers.
This technique could the terms used to determine the nature of unconscious states, and will help define more accurately the chances of recovery. In many cases it may be a chance for someone who was apparently vegetative state to resume active communication with the outside world.

Clip Source: www.abc.net.au

Thursday, 19 June 2008 Dani Cooper
ABC

The voices of people silenced by a completely paralysed body may be heard again through research being showcased in Melbourne today.

Dr Martin Monti, of the Medical Research Council's Cognition and Brain Science Unit in Cambridge, UK, says he has developed a way to communicate with anyone who cannot produce movement but is consciously aware.

He says the research, presented at the Organisation for Human Brain Mapping conference, has implications for the medical diagnosis of people as being in a vegetative state and for determining whether to discontinue feeding.

The research builds on a 2006 study by Dr Adrian Owen, also of the Cambridge centre, who reported in the journal Science that brain scans of a woman who had been in a vegetative state for five months showed her imagining playing tennis and responding to commands.

"The medical system needs to understand how to use it and at some point we have to look at the ethical and legal ramifications.

New Research On Octopuses Sheds Light On Memory

Wed, 18 Jun 2008 19:39:13 GMT

clipped by: Mohir
clipper's remarks: It is not completely understood how these two systems are interconnected, if at all. However, the organization in the octopus demonstrates a sophistication that was not described yet in other animals. In the octopus, the short-term and long-term systems are working in parallel, but not independently. This is so because the long-term memory area -- in addition to its capacity to store long-term memories -- also regulates the rate at which the short-term memory system acquires short-term memories. This regulatory mechanism is probably useful in cases where faster learning is significant for the octopus' survival in emergency or risky situations.

Clip Source: www.sciencedaily.com

Research on octopuses has shed new light on how our brains store and recall memory,

Why octopuses?

Octopuses and other related creatures, known as cephalopods, are considered to be the most intelligent invertebrates because they have relatively large brains and they can be trained for various learning and memory tasks, says Dr. Hochner.

Their behavior repertoire and learning and memory abilities are even comparable in their complexity to those of advanced vertebrates. However, they are still invertebrate mollusks with brains that contain a much fewer number of nerve cells and much simpler anatomical organization than that of vertebrate brains. This unique constellation was utilized to tackle one of the most interesting questions in modern neuroscience, which is how the brain stores and recalls memories

Tags: octopuse, memory

Scans show Huntington's toll on brain

Tue, 17 Jun 2008 16:50:30 GMT

clipped by: pokkets
clipper's remarks: It wasn't known how much degeneration there was before the disease was diagnosed.
This study helps fill in that gap

Clip Source: www.abc.net.au

Tuesday, 17 June 2008 Dani Cooper
ABC

Australian researchers are using new imaging technology to provide an insight into the degenerative effect of Huntington's disease on the brain.

Mapping change: these scans of the brain using diffusion magnetic resonance imaging show white matter tracts that degenerate in people with Huntington's disease (Source: India Bohanna/Howard Florey Institute)

Doctoral student India Bohanna, from the Howard Florey Institute in Melbourne, used diffusion magnetic resonance imaging technology to track the breakdown in structural connections within the brain.

The research was presented at the Organisation for Human Brain Mapping conference being held this week in Melbourne.

The researchers used diffusion MRI, which maps the brain's white matter tracts by measuring the movement of water molecules in the brain.

Bohanna says a breakdown in these structural connections disrupts the brain's communication.

Anatomy of a false memory

Mon, 16 Jun 2008 13:48:45 GMT

clipped by: Mohir

Clip Source: scienceblogs.com

We believe that memory provides us with a faithful record of past events. But in fact, it is well established that memory is reconstructive, and not reproductive, in nature. In retrieval, a memory is pieced together from fragments, but during the reconstruction errors creep in due to our own biases and expectations.

Generally, these errors are small, so despite not being completely accurate, our memories are usually reliable. Occasionally, there are too many errors, and the memory becomes unreliable. In extreme cases, memories can be completely false.

False memory, or confabulation, is completely unintentional, and can occur spontaneously due, for example, to the suggestive power of a leading question or a doctored photograph. It can also following frontal lobe damage due to tumours, head injuries, or ruptured arteries.

Tags: memory, brain

6 iconoclastic discoveries about the brain

Wed, 11 Jun 2008 10:02:06 GMT

clipped by: wildcat
clipper's remarks: let go of the dogma

Clip Source: scienceblogs.com

Neuroscience, like all other branches of science, is fraught with dogmatic ideas about its subject matter. A number of principles have emerged, principles that have been regarded as fundamental to our understanding of brain function.

But the human brain is an organ of bewildering complexity - it is often referred to as the most complex object in the known universe - which doesn't give up its secrets easily. After 100 years of scientific investigation, we still know very little about it.

Dogma 1:

The adult human brain is not plastic.

Dogma 2: The adult human brain cannot regenerate

Dogma 3:

Neurons are the functional elements of the nervous system

Dogma 4:

Neurotransmitters are released from the nerve terminal

Dogma 5:

Neurons are binary switches.

Dogma 6:

Neurons communicate with each other by propagating action potentials

Tags: brain, discoveries, neuroscience, clipversity

Subneural Networks in the Quantum Brain

Mon, 09 Jun 2008 20:40:39 GMT

clipped by: abailart
clipper's remarks: Basically, the neuron or nerve cell, and its synapses is no longer seen as fundamental but as container for smaller structures, notwithstanding the importance of synaptic connectivity.

Clip Source: arxiv.org

Microtubule (MT) networks, subneural paracrystalline cytosceletal structures, seem to play a fundamental role in the neurons. We cast here the complicated MT dynamics in the form of a $1+1$-dimensional non-critical string theory, thus enabling us to provide a consistent quantum treatment of MTs

The {\em microscopic arrow of time}, endemic in non-critical string theory, and apparent here in the self-collapse process, provides a satisfactory and simple resolution to the age-old problem of how the, central to our feelings of awareness, sensation of the progression of time is generated. In addition, the complete integrability of the stringy model for MT we advocate in this work proves sufficient in providing a satisfactory solution to memory coding and capacity. Such features might turn out to be important for a model of the brain as a quantum computer.

Tags: microtubule, subneural

The wasp that walks cockroaches

Fri, 06 Jun 2008 14:17:50 GMT

clipped by: JohnWaterman
clipper's remarks: More icky wasp science

Clip Source: scienceblogs.com

yet another demonstration of the amazing tactics used by these macabre parents to provision their young with food

the jewel wasp

grubs feed on the bodies of cockroaches supplied by their mother. When a female wasp finds a roach, she stings it twice - once in its mid-section to immobilise its front legs, and the second directly into its brain. There, she pumps in a venom that stupefies the roach and changes its behaviour.

not paralysed but it moves sluggishly and shows no desire to flee from danger. In this befuddled state, the jewel wasp can grab the roach by its antennae and walk it around like a dog on a leash. The wasp leads its roach to its nest, where it seals it up and lays an egg on its belly. Even as the larva hatches and starts to eat the roach alive, the hapless insect doesn't struggle or fight

have discovered how the wasp's venom keeps its victim so sedate but otherwise mobile and healthy

cockroaches can be restored to their active ways by injecting

octopamine (see video

[Video]

Scientists probe the memory of bees

Wed, 04 Jun 2008 02:19:12 GMT

clipped by: pokkets
clipper's remarks: The clip suggests that bees brain wiring is divided in a way that is reminiscent of the hemispheres in the human brain. From what I remember, bees had brains long before humans, so perhaps it is the other way around

Clip Source: www.abc.net.au

Stephen Pincock

Honey bees are able to remember the scent of the flowers they visit by allocating different types of memory to their tiny brains, new research suggests.

Bees can do extraordinarily complex things with their pinsized brains

Emeritus Professor Lesley Rogers of the University of New England in Armidale, Australia and Professor Giorgio Vallortigara, of the University of Trento in Italy report their findings this week in the journal PLoS ONE.

The researchers show that bee brains are divided into two halves with different functions in a way that is reminiscent of the hemispheres of the human brain.

"When we asked the bee to recall with its left antenna coated, it could recall the memory of the two scents for up to about three hours, but it wasn't as good thereafter," Rogers says.

"On the other hand, if we coated the right antenna and tested its recall, then initially it didn't do well, but after six hours it could recall."

Obviously they're wired up very efficientl