Tuesday, December 23, 2008

Blind, Yet Seeing - The Brain’s Subconscious Visual Sense - NYTimes.com

The man, a doctor left blind by two successive strokes, refused to take part in the experiment. He could not see anything, he said, and had no interest in navigating an obstacle course — a cluttered hallway — for the benefit of science. Why bother?

When he finally tried it, though, something remarkable happened. He zigzagged down the hall, sidestepping a garbage can, a tripod, a stack of paper and several boxes as if he could see everything clearly. A researcher shadowed him in case he stumbled.

"You just had to see it to believe it," said Beatrice de Gelder, a neuroscientist at Harvard and Tilburg University in the Netherlands, who with an international team of brain researchers reported on the patient on Monday in the journal Current Biology. A video is online at www.beatricedegelder.com/books.html.

The study, which included extensive brain imaging, is the most dramatic demonstration to date of so-called blindsight, the native ability to sense things using the brain's primitive, subcortical — and entirely subconscious — visual system.

Scientists have previously reported cases of blindsight in people with partial damage to their visual lobes. The new report is the first to show it in a person whose visual lobes — one in each hemisphere, under the skull at the back of the head — were completely destroyed. The finding suggests that people with similar injuries may be able to recover some crude visual sense with practice.

"It's a very rigorously done report and the first demonstration of this in someone with apparent total absence of a striate cortex, the visual processing region," said Dr. Richard Held, an emeritus professor of cognitive and brain science at the Massachusetts Institute of Technology, who with Ernst Pöppel and Douglas Frost wrote the first published account of blindsight in a person, in 1973.

The man in the new study, an African living in Switzerland at the time, suffered the two strokes in his 50s, weeks apart, and was profoundly blind by any of the usual measures. Unlike people suffering from eye injuries, or congenital blindness in which the visual system develops abnormally, his brain was otherwise healthy, as were his eyes, so he had the necessary tools to process subconscious vision. What he lacked were the circuits that cobble together a clear, conscious picture.

The research team took brain scans and magnetic resonance images to see the damage, finding no evidence of visual activity in the cortex. They also found no evidence that the patient was navigating by echolocation, the way that bats do. Both the patient, T. N., and the researcher shadowing him walked the course in silence.

The man himself was as dumbfounded as anyone that he was able to navigate the obstacle course.

"The more educated people are," Dr. de Gelder said, "in my experience, the less likely they are to believe they have these resources that they are not aware of to avoid obstacles. And this was a very educated person."

Scientists have long known that the brain digests what comes through the eyes using two sets of circuits. Cells in the retina project not only to the visual cortex — the destroyed regions in this man — but also to subcortical areas, which in T. N. were intact. These include the superior colliculus, which is crucial in eye movements and may have other sensory functions; and, probably, circuits running through the amygdala, which registers emotion.

In an earlier experiment, one of the authors of the new paper, Dr. Alan Pegna of Geneva University Hospitals, found that the same African doctor had emotional blindsight. When presented with images of fearful faces, he cringed subconsciously in the same way that almost everyone does, even though he could not consciously see the faces. The subcortical, primitive visual system apparently registers not only solid objects but also strong social signals.

Dr. Held, the M.I.T. neuroscientist, said that in lower mammals these midbrain systems appeared to play a much larger role in perception. In a study of rats published in the journal Science last Friday, researchers demonstrated that cells deep in the brain were in fact specialized to register certain qualities of the environment.

They include place cells, which fire when an animal passes a certain landmark, and head-direction cells, which track which way the face is pointing. But the new study also found strong evidence of what the scientists, from the Norwegian University of Science and Technology in Trondheim, called "border cells," which fire when an animal is close to a wall or boundary of some kind.

All of these types of neurons, which exist in some form in humans, may too have assisted T. N. in his navigation of the obstacle course.

In time, and with practice, people with brain injuries may learn to lean more heavily on such subconscious or semiconscious systems, and perhaps even begin to construct some conscious vision from them.

"It's not clear how sharp it would be," Dr. Held said. "Probably a vague, low-resolution spatial sense. But it might allow them to move around more independently."


The Evidence Gap - Drug Rehabilitation or Revolving Door?

Their first love might be the rum or vodka or gin and juice that is
going around the bonfire. Or maybe the smoke, the potent marijuana
that grows in the misted hills here like moss on a wet stone.

But it hardly matters. Here as elsewhere in the country, some users
start early, fall fast and in their reckless prime can swallow,
snort, inject or smoke anything available, from crystal meth to
prescription pills to heroin and ecstasy. And treatment, if they get
it at all, can seem like a joke.

"After the first couple of times I went through, they basically told
me that there was nothing they could do," said Angella, a 17-year-old
from the central Oregon city of Bend, who by freshman year in high
school was drinking hard liquor every day, smoking pot and sampling a
variety of harder drugs. "They were like, 'Uh, I don't think so.' "

She tried residential programs twice, living away from home for three
months each time. In those, she learned how dangerous her habit was,
how much pain it was causing others in her life. She worked on
strengthening her relationship with her grandparents, with whom she
lived. For two months or so afterward she stayed clean.

"Then I went right back," Angella said in an interview. "After a
while, you know, you just start missing your friends."

Every year, state and federal governments spend more than $15
billion, and insurers at least $5 billion more, on substance-abuse
treatment services for some four million people. That amount may soon
increase sharply: last year, Congress passed the mental health parity
law, which for the first time includes addiction treatment under a
federal law requiring that insurers cover mental and physical
ailments at equal levels.

Many clinics across the county have waiting lists, and researchers
estimate that some 20 million Americans who could benefit from
treatment do not get it.

Yet very few rehabilitation programs have the evidence to show that
they are effective. The resort-and-spa private clinics generally do
not allow outside researchers to verify their published success
rates. The publicly supported programs spend their scarce resources
on patient care, not costly studies.

And the field has no standard guidelines. Each program has its own
philosophy; so, for that matter, do individual counselors. No one
knows which approach is best for which patient, because these
programs rarely if ever track clients closely after they graduate.
Even Alcoholics Anonymous, the best known of all the substance-abuse
programs, does not publish data on its participants' success rate.

"What we have in this country is a washing-machine model of addiction
treatment," said A. Thomas McClellan, chief executive of the
nonprofit Treatment Research Institute, based in Philadelphia. "You
go to Shady Acres for 30 days, or to some clinic for 60 visits or 60
doses, whatever it is. And then you're discharged and everyone's
crying and hugging and feeling proud — and you're supposed to be cured."

He added: "It doesn't really matter if you're a movie star going to
some resort by the sea or a homeless person. The system doesn't work
well for what for many people is a chronic, recurring problem."

In recent years state governments, which cover most of the bill for
addiction services, have become increasingly concerned, and some,
including Delaware, North Carolina, and Oregon, have sought ways to
make the programs more accountable. The experience of Oregon, which
has taken the most direct and aggressive action, illustrates both the
promise and perils of trying to inject science into addiction treatment.

More ...


Monday, December 22, 2008

Woman Sued for Rescuing Friend

No good deed goes unpunished, or so goes the saying.

Such was the case with Lisa Torti, who is being sued for pulling a now-paralyzed friend from the wreckage of a Los Angeles car accident in 2004.

The victim's lawyers claim the Good Samaritan bumbled the rescue and caused injury by yanking her friend "like a rag doll" to safety.

But Torti -- now a 30-year-old interior designer from Las Vegas -- said she thought she had seen smoke and feared the car would explode. She claims she was only trying to help her friend, Alexandra Van Horn, and her own life has been adversely affected by the incident.

"I know [Van Horn] has a lot of financial issues and her life has changed," she said. "But it's not my fault. I can't be angry at her, only the path she has chosen to take. I can only pray it helps her."

"I don't have any more fight left," Torti told ABCNews.com, choking back tears. "It's really emotional."

The California Supreme Court ruled this week that Van Horn may sue Torti for allegedly causing her friend's paralysis. The case -- the first of its kind -- challenges the state's liability shield law that protects people who give emergency assistance.

Only Medical Workers Immune

The court ruled 4-3 that only those administering medical care have legal immunity, but not those like Torti, who merely take rescue action. The justices said that the perceived danger to Van Horn in the wrecked car was not "medical."

The court majority said the 1980 Emergency Medical Service Act, which Torti's lawyers cited for protection, was intended only to encourage people to learn first aid and use it in emergencies, not to give Good Samaritans blanket immunity when they act negligently.

Van Horn's lawsuit will go on to trial court to determine if Torti is to blame for Van Horn's paralysis.

But some legal experts say the ruling may discourage people from trying to save lives.

"What they are saying is that if you pull someone out of a pool, if you provide CPR, you do have a defense," said Torti's lawyer, Jody Steinberg.

"It seems to defy logic," he said. "At a certain point anyone who instructs or educates [in emergencies] will advise that you must hesitate. Those split-second decisions will be gone and someone could die."

More ...


Sunday, December 21, 2008

Abuse of Prescription Drugs Rises Among Stressed Iraqi Soldiers - NYTimes.com

BAGHDAD — For an Iraqi Army soldier patrolling Baghdad's unpredictable streets, each 12-hour shift is an exercise in terror and uncertainty.

So Ahmed Qasim pops a small white tablet called Artane to help him through his duties.

"For me, it helps me to get the job done," he said. "I can't bear working without taking Artane. It makes me happy and high, but I still can control myself."

The abuse of prescription drugs, widely available in Iraq on the black market and through private pharmacies, has significantly increased since 2003, doctors and other health specialists say, nourished by the stresses of the war and the lack of strict government regulation.

Dealers do a brisk business in tranquilizers, painkillers and other drugs, specialists say, and drug abuse is a problem in the prisons and among Iraqis who live in poor neighborhoods or who are unemployed.

But in recent years, Iraqi soldiers and police officers have also turned to drugs to ease the stresses of their jobs. In particular, they are abusing Artane, a medication that is used to treat Parkinson's disease and that can have euphoric effects when used in high doses.

"They believe that this Artane allows them to become courageous, to become brave," said one doctor, who spoke on the condition of anonymity because he was not authorized to speak publicly. about the issue.

"They take it so that there is no anxiety, no fear," he said, "so they can break down doors and enter houses with no shame."

No clear evidence exists that the misuse of prescription drugs has a significant effect on how soldiers and police officers perform their duties. Nor are any figures available on how widespread drug abuse is in the security forces or whether most of those who use the drugs do so daily.

More ...

New Doctors Awash in Debt - NYTimes.com

Almost one-quarter of U.S. medical students now graduate from medical school with $200,000 or more in debt, an expense that limits entry to the profession, The New England Journal of Medicine said on Thursday.

The median cost of attending a year of medical school, including all fees, is now $62,243 at private schools and $44,390 for state residents at public schools.

Most of the $2.5 billion in financial assistance available to medical students comes in the form of non-subsidized loans. Few top schools have the resources to discount tuition for students from lower-income families, according to Dr. Robert Steinbrook, a national correspondent for the journal.

The steep costs may discourage low-income students from going to medical school, and sway graduates toward higher-earning specialties like radiology and away from lower-paying ones like primary care, Dr. Steinbrook said.