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PURETICS...

PURETICS...


Interesting Findings And World Unfolding Through My Eyes.

Monday, September 24, 2007

Dear C &Dear L

Dear Cecil:

After staring steadily out the window for a few minutes and then shifting my gaze to the blank wall across the room, I can still see the ghost image of the window and some objects around it. What's the straight dope on the cause of the negative afterimage? --L.W., Guadalajara, Mexico

Dear L.:

Low-quality drugs were usually the problem when I was a kid, L., but I'm sure this is not a concern for young folks today. Basically, there are two kinds of afterimages--negative afterimages (the kind you noticed), and complementary afterimages (i.e., red becomes green, blue becomes orange, etc.). The latter are the kind you find in intro-to-psych textbooks, where you stare at, say, a green figure for a while, then shift your eyeballs to a blank page, whereupon you see a red ghost image that last a few seconds.

Related to this are aftereffects, which usually have to do with perception of motion, orientation, and whatnot. For example, next time you're chugging down the highway in the back of somebody's station wagon, stare fixedly at the lane stripes receding in the distance. When the car stops, it'll look as though the stripes are heading toward you--i.e., as if the car were backing up. Similarly, if you stare for several minutes at a set of lines that is tilted out of the vertical, a set of lines that actually is vertical will appear to be tilted in the opposite direction.

Psychologists get paid millions to dig up tidbits like this, but they're not so hot when it comes to explaining what causes them. The best guess is that afterimages are related somehow to nerve fatigue. It's known that if you stare at a brightly colored figure long enough, after a while the color seems much less intense. It's also known that at various points in the eye-to-brain nerve linkage there are things called "opponent process" cells, which fire faster than normal in response to a given color, but slower than normal in response to that color's complement.

One scenario has it that if you stare at, say, a red patch long enough, your red-sensitive opponent-process cells get all tuckered out. Then, when you avert your eyes to a neutral color, the fact that these cells are ticking along more slowly than usual is interpreted by the brain to mean you're seeing green.

This sounds plausible until you realize that afterimage is actually an amazingly complex phenomenon. For instance, sometimes (usually after a very brief stimulus) you'll see a positive afterimage. Then we have the formidable task of explaining motion aftereffects. If I were you I'd just keep my eyes closed until the whole thing went away.

--CECIL ADAMS

Posted by Ajay :: 5:23 PM :: 0 comments

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He Took 40,000 Ecstasy Pills

The strange case of the man who took 40,000 ecstasy pills in nine years


· Usage increased to 25 tablets a day at peak
· Memory problems and paranoia may be lasting

David McCandless
Tuesday April 4, 2006
The Guardian


Doctors from London University have revealed details of what they believe is the largest amount of ecstasy ever consumed by a single person. Consultants from the addiction centre at St George's Medical School, London, have published a case report of a British man estimated to have taken around 40,000 pills of MDMA, the active ingredient in ecstasy, over nine years. The heaviest previous lifetime intake on record is 2,000 pills.
Though the man, who is now 37, stopped taking the drug seven years ago, he still suffers from severe physical and mental health side-effects, including extreme memory problems, paranoia, hallucinations and depression. He also suffers from painful muscle rigidity around his neck and jaw which often prevents him from opening his mouth. The doctors believe many of these symptoms may be permanent.

The man, known as Mr A in the report in the scientific journal Psychosomatics, started using ecstasy at 21. For the first two years his use was an average of five pills per weekend. Gradually this escalated until he was taking around three and a half pills a day. At the peak, the man was taking an estimated 25 pills every day for four years. After several severe collapses at parties, Mr A decided to stop taking ecstasy. For several months, he still felt he was under the influence of the drug, despite being bedridden.

Hallucinations

His condition deteriorated and he began to experience recurrent tunnel vision and other problems including hallucinations, paranoia and muscle rigidity. "He came to us after deciding that he couldn't go on any more," said Dr Christos Kouimtsidis, the consultant psychiatrist at St George's Medical School in Tooting who treated him for five months. "He was having trouble functioning in everyday life."

The doctors discovered that the man was suffering from severe short-term memory problems of a type usually only seen in lifetime alcoholics. But evaluating the full extent of his condition was difficult as his concentration and attention was so impaired he was unable to follow the simple tasks involved in the test.

"This was an exceptional case. His long- term memory was fine but he could not remember day to day things - the time, the day, what was in his supermarket trolley," said Dr Kouimtsidis. "More worryingly, he did not seem aware himself that he had these memory problems."

With no mental illness in his family and no prior psychiatric history, the doctors concluded that his unique condition was direct result of his intense ecstasy use.

"This is obviously an extreme case so we should not blow any observations out of proportion," says Dr Kouimtsidis. "But if this is what is happening to very heavy users, it might be an indication that daily use of ecstasy over a long period of time can lead to irreversible memory problems and other cognitive deficits."

For 10 years, MDMA has been suspected of causing these kinds of effects in heavy users. It is thought to be due to its disruption of the regulation of serotonin, a brain chemical believed to play a role in mood and memory. It remains unclear whether these effects are the result of permanent neurotoxic damage or just temporary reversible alterations in the brain.

A special two-part MDMA study in recent issues of the Journal of Psychopharmacology (available online at sagepub), suggests long-term side-effects may be temporary. The researchers from the University Of Louisiana could find no significant relationship between depression and recreational ecstasy use.

In the case of Mr A, a structural MRI brain scan failed to show any obvious damage or atrophy in his brain. However, these results, says Dr Kouimtsidis, are difficult to interpret. "A scan of this type is not sensitive enough," he said.

Such limitations in brain scanning technology, along with ethical and legal barriers to giving MDMA to human test subjects, have limited direct observation of the drug's effects in humans.

Instead, scientists have had to use recreational drug users as subjects in their studies. Conclusions from this are often flawed because few, if any, drugs users use ecstasy in isolation.

Cannabis user

Mr A was also a heavy cannabis user, and when he was encouraged to decrease his use, his paranoia and hallucinations disappeared and his anxiety abated. But his memory and concentration problems remained, leading the doctors to suspect that these may be permanent disabilities.

When he was admitted to a specialist brain injury unit and put on anti-psychotic medication, he did start to show some improvement. "Unfortunately, he discharged himself before we were able to complete the assessment," says Dr Kouimtsidis. "We continued to support him. But he started to use cannabis again and he dropped out. We tried to re-engage him but we lost him about a year ago."

The Guardian made several attempts to find the man without success.

Effects of ecstasy

MDMA is one of the most intensely studied recreational drugs in history. But despite thousands of research papers and studies, scientific evidence on the side-effects remains inconclusive.

Death by overdose

Undoubtedly, large amounts of ecstasy can lead to over-heating which in turn, in rare cases, can trigger fatal heat stroke. Many factors contribute: number and strength of pills taken, environment, alcohol-consumption, body weight - but women seem more at risk. The bulk of ecstasy-related deaths around the world have been young women.

Water-poisoning

Panicking users, fearing they are overdosing, drink too much water and provoke hyponaetraemia (water-poisoning). Leah Betts died after drinking 14 pints in just 90 minutes. The recommended amount of water to drink per hour is one pint.

Toxic reactions

Much of the reports of toxic reactions are muddled with overdose or water-poisoning deaths. There is no clear evidence that some people suffer allergic reactions to ecstasy. However, around 10% of Western users do lack a key liver enzyme CYP2D6 needed to break down MDMA. This may make them more sensitive to the effects and more prone to accidental overdose.

Depression

Many weekend users report a mid-week mood dip. This is suspected to be related MDMA's effect on serotonin, but hard evidence is lacking. In heavy users, dips can turn to crashes and depression. However studies suggest this effect reverses after a 2-3 month abstinence.

Positive effects

Users still claim "long lasting improvements in self-awareness, self-esteem, openness and insight into personal problems", reports the study from the University Of Louisiana. In the US, research continues into the use of MDMA-assisted psychotherapy to treat Post Traumatic Stress Disorder.

Posted by Ajay :: 10:17 AM :: 0 comments

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Going Home Alone?

One year, shortly before graduation, the mother of a friend came to visit him at college. As they walked across campus after dinner, a young woman he knew stopped to say hello and ask where he was going. "He's going home," his mother snapped. "Alone."

Has it really come to this? Has adult obsession with college sex reached such a pitch that a parent assumes that every cordial conversation will, without his or her intervention, end in frantic intercourse?


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Actually, we understand parents' alarm. College today is portrayed almost exclusively as a sexual free-for-all, where undergrad action is effortless and frequent, where randy young things not so much leap into the sack as never leave it in the first place.

Rolling Stone calls it "the booze-fueled culture of the never-ending hookup." In her book "Unhooked," The Washington Post's Laura Sessions Stepp sniffs that hookups are as "common as a cold." Bill O'Reilly airs furtive footage on Fox News of "pure debauchery" at Brown University's annual SexPowerGod party. And of course, in Tom Wolfe's impossible-not-to-cite novel "I Am Charlotte Simmons," set on a campus where sex is in the air -- sorry, where the air is "humid with it! Tumid with it! Lubricated with it! Gorged with it!" -- students practically major in "herky-jerky . . . bang bang bang." One envisions RU-486 available at the dining hall salad bar, next to the croutons.

But as the Class of 2011 settles in on campus this month, we're betting that the students are discovering the cold-shower truth: The type of action they're likely to get is more hanky than panky.

We say this at our own peril. As the editors of IvyGate, a blog that dines out on all that is base and scandalous about the Ivy League, we have written about students and sex once or twice. It's hard not to, when even the smallest incidents get hyped to the max.

This year, two weeks before Valentine's Day, we posted an e-mail that the beleaguered master of a Yale residential college had sent to his charges -- subject line: "Shower Stalls are for Showering" -- asking an unnamed intimate couple to please stop clogging the bathroom drain. Hilarious? Absolutely. (The man has a PhD!) Did we give it a second thought? Nah. Not, that is, until a New Haven newspaper got wind of the professor's plea. And then the Associated Press. And then about 130 news outlets worldwide, including the "Today" show.

It wasn't the first time, obviously, that a campus sex story had been blown out of proportion. Last fall, the New York Daily News ran a thoughtful, nuanced article with the headline "WILD SEX 101: S&M Clubs, Nude Parties, Porn, X-Rated Romps Rule at Columbia." Having gone to Columbia, where we had experience with only the third item on that list, we read eagerly. Had the school really become a "playpen for sexual hijinks" in the months since we'd graduated? By e-mail and instant message, we canvassed some friends for our blog: Forget the kinky part; how often are you having sex at all? Here are some of the responses:

"Once every six months. Columbia is a rough world for single people."

"The average in the engineering school is probably like once a semester."

"Either I missed out or everyone else in college isn't having sex at all."

"Random hookups do happen, but it is probably rare for most students. At night people just go back to their rooms and finish their homework, or maybe heat up a Hot Pocket
More at:http://www.washingtonpost.com/wp-dyn/content/article/2007/09/21/AR2007092101543_2.html?nav=hcmodule

Posted by Ajay :: 10:13 AM :: 0 comments

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Will Life Be Worth Living In 2000AD?

What sort of life will you be living 39 years from now? Scientists have looked into the future and they can tell you.

It looks as if everything will be so easy that people will probably die from sheer boredom.

You will be whisked around in monorail vehicles at 200 miles an hour and you will think nothing of taking a fortnight's holiday in outer space.

Your house will probably have air walls, and a floating roof, adjustable to the angle of the sun.

oors will open automatically, and clothing will be put away by remote control. The heating and cooling systems will be built into the furniture and rugs.

You'll have a home control room - an electronics centre, where messages will be recorded when you're away from home. This will play back when you return, and also give you up-to-the minute world news, and transcribe your latest mail.

You'll have wall-to-wall global TV, an indoor swimming pool, TV-telephones and room-to-room TV. Press a button and you can change the décor of a room.

The status symbol of the year 2000 will be the home computer help, which will help mother tend the children, cook the meals and issue reminders of appointments.

Cooking will be in solar ovens with microwave controls. Garbage will be refrigerated, and pressed into fertiliser pellets.

Food won't be very different from 1961, but there will be a few new dishes - instant bread, sugar made from sawdust, foodless foods (minus nutritional properties), juice powders and synthetic tea and cocoa. Energy will come in tablet form.

At work, Dad will operate on a 24 hour week. The office will be air-conditioned with stimulating scents and extra oxygen - to give a physical and psychological lift.

Mail and newspapers will be reproduced instantly anywhere in the world by facsimile.

There will be machines doing the work of clerks, shorthand writers and translators. Machines will "talk" to each other.

It will be the age of press-button transportation. Rocket belts will increase a man's stride to 30 feet, and bus-type helicopters will travel along crowded air skyways. There will be moving plastic-covered pavements, individual hoppicopters, and 200 m.p.h. monorail trains operating in all large cities.

The family car will be soundless, vibrationless and self-propelled thermostatically. The engine will be smaller than a typewriter. Cars will travel overland on an 18 inch air cushion.

Railways will have one central dispatcher, who will control a whole nation's traffic. Jet trains will be guided by electronic brains.

n commercial transportation, there will be travel at 1000 m.p.h. at a penny a mile. Hypersonic passenger planes, using solid fuels, will reach any part of the world in an hour.

By the year 2020, five per cent of the world's population will have emigrated into space. Many will have visited the moon and beyond.

Our children will learn from TV, recorders and teaching machines. They will get pills to make them learn faster. We shall be healthier, too. There will be no common colds, cancer, tooth decay or mental illness.

Medically induced growth of amputated limbs will be possible. Rejuvenation will be in the middle stages of research, and people will live, healthily, to 85 or 100.

There's a lot more besides to make H.G. Wells and George Orwell sound like they're getting left behind.

And this isn't science fiction. It's science fact - futuristic ideas, conceived by imaginative young men, whose crazy-sounding schemes have got the nod from the scientists.

It's the way they think the world will live in the next century - if there's any world left!

Posted by Ajay :: 10:09 AM :: 0 comments

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