By age 60, more than half of adults have concerns about their memory. However, minor memory lapses that occur with age are not usually signs of a serious problem, such as Alzheimer’s disease, but rather the result of normal changes in the structure and function of the brain. This report describes these normal age-related changes and other more serious causes of memory loss — and how to distinguish between them.
The way you live, what you eat and drink, and how you treat your body can affect your memory just as much as your physical health and well-being. Here are five things you can do every day to keep both your mind and body sharp.
1. Manage your stress. The constant drumbeat of daily stresses such as deadline pressures or petty arguments can certainly distract you and affect your ability to focus and recall.Always negative thinking against an agenda is the bigger problem is an ongoing sense of anxiety — that can lead to memory impairment. If you don’t have a strategy in place for managing your stress, protecting your memory is one reason to get one.Positive thinking, deep breathing, meditation, yoga, and a “mindful” approach to living can all help.
2. Get a good night’s sleep. People who don’t sleep well at night tend to be more forgetful than people who sleep soundly. A good night’s sleep is essential for consolidating memories. The most common reason for poor sleep is insomnia — difficulty falling asleep or staying asleep. Unfortunately, many medicines used to treat insomnia can also impair memory and general brain function. That’s why it’s best to try improving your sleep habits first and turn to medication only if those steps don’t help. If you do need sleep aids, use the lowest dose for the shortest time needed to get your sleep back on track.
3. If you smoke, quit. Easier said than done, certainly — but if you need additional motivation, know that smokers have a greater degree of age-related memory loss and other memory problems than nonsmokers. People who smoke more than two packs of cigarettes a day at midlife have more than double the risk of developing dementia in old age compared with nonsmokers. However, those who stop smoking by midlife and those who smoke less than half a pack a day have a similar a risk of dementia as people who have never smoked.
4. If you drink alcohol, do so moderately. Drinking too much alcohol increases the risk for memory loss and dementia. People with alcoholism have difficulty performing short-term memory tasks, such as memorizing lists. Another type of memory loss associated with alcohol use is called Korsakoff’s syndrome. In this condition, long-term vitamin B1 deficiency, combined with the toxic effects of alcohol on the brain, can trigger sudden and dramatic amnesia. In some cases this memory loss is permanent, but if caught early, it can be reversed to some degree.
5. Protect your brain from injury.Head trauma is a major cause of memory loss and increases the risk of developing dementia. Always use the appropriate gear during high-speed activities and contact sports. Wear a helmet when bicycling, riding on a motorcycle, in-line skating, and skiing. Wear seat belts when riding in motor vehicles. Car accidents are by far the most common cause of brain injury, and wearing a seat belt greatly reduces the chances of severe head injury.
The participants were asked to feel a building block and then match the object felt with two blocks, one square and the other circular.
Blind children from India’s hinterland have found themselves a place in history by helping researchers resolve a profound and long-standing problem that perplexed philosophers and neuroscientists for over three centuries.
Posed for the first time in 1688 by Irish scientist and politician William Molyneux, the question is elegantly simple: can a person who has been blind from birth but gained sight in adulthood visually discriminate between objects that were previously identifiable only by touch?
The answer seems to be a definite “no”. That’s the conclusion of a team of Indian and American scientists after their studies involving blind children in rural India whose eyesight was restored surgically. In other words, a person’s ability to learn the correspondence between how an object looks and how it feels is not innate; it needs to be learnt. The study appeared yesterday in Nature Neuroscience.
The Molyneux question has been the subject of much debate in philosophy and neuroscience over the past three centuries, says MIT’s Richard Held, the first author of the paper. It’s important for two reasons, he says. Philosophically speaking, it touches upon the core of the “nature versus nurture” debate. It also addresses a deep scientific question: do the various senses of a living organism share an innate common space?
Though efforts to answer the question began not long after it was first posed, it had thus far remained unresolved. The primary reason for this is that in the West, a majority of curable congenital blindness cases are detected in infancy and treated as early as possible. But the scientists working with Project Prakash — which Sinha launched in 2004 — however, had an opportunity to take a fresh look at the problem. They had been working with children with vision disabilities in rural India as part of the humanitarian venture. The country is said to have the highest number of blind children in the world — more than one million.
Most cases of blindness in India are caused by vitamin A deficiency, cataracts, retinal or optical dystrophies, or microphthalmos (poorly developed eyes). About half the cases are treatable or preventable, but many never receive medical care, especially in rural areas.
Under the project, the scientists have so far screened more than 20,000 children in some of the most backward villages in Uttar Pradesh, Haryana, Rajasthan and Madhya Pradesh. “Over 700 children have been treated for conditions ranging from severe refractive error to congenital blindness,” says Sinha, a co-author of the study. The medical care was provided at New Delhi’s eye hospital, Shroff’s Charity Eye Hospital, a project partner.
For their study, the scientists chose five children who were blind from birth owing to a congenital cataract or an opaque cornea. After surgery — a cataract removal or a corneal transplant — the participants were asked to feel a building block and then match the object felt with one or two blocks (of two different shapes — one square and the other circular). The children were unable to match the blocks they felt with what they only saw. Significantly, their performance improved substantially five days later, although they didn’t receive any kind of training.
This rapid improvement was surprising, says Yuri Ostrovsky, another MIT researcher associated with the study. He points out that many visual tasks, such as face perception, can take six to 12 months to learn after sight is restored. “The outcome has been a surprise — one that has important implications for theories regarding how the brain learns to acquire a coherent account of the complex environment,” Held told KnowHow.
Sinha, who holds a BTech from the Indian Institute of Technology, Delhi, says the project has been an eye opener in more ways than one. It served a dual purpose: providing sight to blind children and advancing fundamental science. This, along with earlier findings from Project Prakash, shows that the human brain retains an impressive ability to launch programmes of visual learning well after the normal period of their deployment has passed.
“It has helped clear several myths regarding vision. Most eye doctors hesitate to treat older patients because they believe the brain is incapable of learning to see after age six or seven,” Sinha told KnowHow. “Our work has broken this dogma.”
The results of the study are significant for basic neuroscience as well as paediatric ophthalmology and implementation of later-stage blindness treatment programmes.
Patients often fail to take their medication properly. Technology steps in with some ideas. Amber Dance reports .
Did you take your medicine today?” Soon, patients won’t have to rely on their memories for the answer. Scientists are developing tablets and capsules that track when they’ve been popped, turning the humble pill into a high-tech monitoring machine. The goal: new devices to help people take their medicines on time and improve the results of clinical trials for new drugs. CLICK & SEE THE PICTURES
Doctors can already prescribe pills that release drugs slowly or at a specific time. They even have camera pills that take snaps of their six to 12-metre journey through the gastrointestinal tract. The new pills tote microchips that make them even cleverer: they will report back to a recorder or smart phone exactly what kind and how much medicine has gone down the hatch and landed in the stomach. Someday they may also report on heart rate and other bodily data.
This next generation of pills is all about compliance, as it’s termed in doctor-speak — the tendency of patients to follow their doctors’ instructions (or not). According to the World Health Organisation (WHO), half of patients don’t take their pills properly. They skip doses, take the wrong amount at the wrong time or simply ignore prescriptions altogether.
The most common reason for medication mistakes is forgetfulness, particularly among the elderly. “The number of prescriptions they get is mind-boggling,” says Jill Winters, dean, Columbia College of Nursing in Milwaukee, Wisconsin. According to a 2004 report by the Centers for Disease Control and Prevention and the Merck Institute of Aging and Health, the average 75-year-old takes five different drugs.
Often, occasional lapses don’t matter. Smart pills like these are “not for your aspirin or even simple antibiotics,” says Maysam Ghovanloo, an electrical engineer at the Georgia Institute of Technology in Atlanta. The new technology is aimed at time-sensitive or costly medications.
For certain medications, not taking every pill can have serious consequences. For example, those mentally ill may require regular treatment to stay stable. Chemotherapy drugs and antibiotics for treating tuberculosis (TB) are also time-sensitive.
Blood pressure (BP) medication works only when taken on a regular basis; suddenly stopping it can cause the BP to skyrocket, says Daniel Touchette, a pharmacist and researcher at the University of Illinois, Chicago.
With drugs for transplant patients, a person who misses a dose risks rejection of the new organ. Novartis International AG, based in Basel, Switzerland, is developing pills for transplant recipients; the pills communicate with a patch on the skin when they reach the stomach.
And in the case of TB, treatment requires a six-month course of antibiotics that come with side effects such as nausea and heartburn. Many people don’t understand why they have to keep taking the unpleasant drugs once they feel better — but going off the medication may make patients contagious again and allow drug-resistant TB to develop.
Yet another arena where compliance is crucial is clinical drug trials. Drugmakers can only be sure their medicine works if they’re sure subjects are actually taking it as directed. For now, experimenters rely on diaries where participants record their medication use. But people may fudge the data, not wanting to admit they dropped a pill down the drain or forgot to take it for a few days. To account for those who miss their medicines, firms have to spend extra — trials cost hundreds of millions of dollars — for larger trials just so enough people will actually take the drug.
Technology already offers some solutions, with mobile phone reminders and pill bottles that record when they’re opened. But none of these actually confirms that the medicine has been swallowed.
Ghovanloo hopes to improve compliance with a necklace that records every time a special pill slides down the esophagus. He calls it MagneTrace. By sounding an alarm or sending a mobile phone message, the necklace also would inform the wearer when it’s time for another dose. Caretakers or doctors could monitor the signals too.
The system works by radio-frequency identification, or RFID. Three magnets on a choker-type necklace act like pillars, continually surveying the neck. The pill contains an RFID chip to communicate with the magnets. When Ghovanloo tested the system in an artificial neck made of PVC pipe, the necklace detected 94 per cent of pills passing through it. He hopes to get that number up to 99 per cent and is adding a microchip that will also transmit information about the specific drug taken and its dose.
Ghovanloo coats the chips with a non-reactive material so that after the medicine dissolves, the hardware simply passes through and out of the digestive tract. However, Ghovanloo says he needs make the design more fashionable. “Right now, it’s not something that a lady would be willing to wear,” he says. For men, he might embed the device in a shirt collar.
Rizwan Bashirullah, an electrical engineer at the University of Florida in Gainesville, is also working on pills that will confirm they’ve been taken. “They’re essentially little stickers,” he says of his technology, called the ID-Cap. Gainesville-based eTect is developing the product.
Each sticker contains three components: a microchip, an antenna and an acid sensor. Altogether it’s approximately half the size of a postage stamp, says eTect President Eric Buffkin. The sensor activates the device when it lands in the acid environment of the stomach, and the chip uses the antenna to send electronic signals directly through the body’s tissues to a receiver, worn on a wristband. The silver antenna and sensor dissolve into safe components; these and the microchip, about as big as a grain of sand, are flushed out of the gut. Over the next year, the company plans to test the capsule for safety in animals and people, Buffkin says.
Source : Los Angerles Times
Published byThe Telegraph ( Kolkata India)
Swine flu is common in swine and rare in humans. People who work with swine, especially people with intense exposures, are at risk of catching swine influenza if the swine carry a strain able to infect humans. However, these strains rarely are able to pass from human to human. Rarely, SIV mutates into a form able to pass easily from human to human. The strain responsible for the 2009 swine flu outbreak is believed to have undergone such a mutation. This virus is named swine flu because one of its surface proteins is similar to viruses that usually infects pigs, but this strain is spreading in people and it is unknown if it infects pigs.
It is an infection caused by any one of several types of swine influenza viruses. Swine influenza virus (SIV) or swine-origin influenza virus (S-OIV) is any strain of the influenza family of viruses that is endemic in pigs.As of 2009, the known SIV strains include influenza C and the subtypes of influenza A known as H1N1, H1N2, H2N1, H3N1, H3N2, and H2N3.
In humans, the symptoms of swine flu are similar to those of influenza and of influenza-like illness in general, namely chills, fever, sore throat, muscle pains, severe headache, coughing, weakness and general discomfort. The strain responsible for the 2009 swine flu outbreak in most cases causes only mild symptoms and the infected person makes a full recovery without requiring medical attention and without the use of antiviral medicines.
Of the three genera of human flu, two are endemic also in swine: Influenzavirus A (common) and Influenzavirus C (rare). Influenzavirus B has not been reported in swine. Within Influenzavirus A and Influenzavirus C, the strains endemic to swine and humans are largely distinct.
The swine flu is likely a descendant of the infamous “Spanish flu” that caused a devastating pandemic in humans in 1918–1919. In less than a year, that pandemic killed more an estimated 50 million people worldwide. Descendants of this virus have persisted in pigs; they probably circulated in humans until the appearance of the Asian flu in 1957, and reemerged in 1977. Direct transmission from pigs to humans is rare, with 12 cases in the U.S. since 2005.
The flu virus is perhaps the trickiest known to medical science; it constantly changes form to elude the protective antibodies that the body has developed in response to previous exposures to influenza or to influenza vaccines. Every two or three years the virus undergoes minor changes. Then, at intervals of roughly a decade, after the bulk of the world’s population has developed some level of resistance to these minor changes, it undergoes a major shift that enables it to tear off on yet another pandemic sweep around the world, infecting hundreds of millions of people who suddenly find their antibody defenses outflanked. Even during the Spanish flu pandemic, the initial wave of the disease was relatively mild and the second wave was highly lethal.In 1957, an Asian flu pandemic infected some 45 million Americans and killed 70,000. Eleven years later, lasting from 1968 to
1969, the Hong Kong flu pandemic afflicted 50 million Americans and caused 33,000 deaths, costing approximately $3.9 billion.
In 1976, about 500 soldiers became infected with swine flu over a period of a few weeks. However, by the end of the month investigators found that the virus had “mysteriously disappeared” and there were no more signs of swine flu anywhere on the post. There were isolated cases around the U.S. but those cases were supposedly to individuals who caught the virus from pigs.
Medical researchers worldwide, recognizing that the swine flu virus might again mutate into something as deadly as the Spanish flu, were carefully watching the latest 2009 outbreak of swine flu and making contingency plans for a possible global pandemic.
Swine influenza virus is common throughout pig populations worldwide. Transmission of the virus from pigs to humans is not common and does not always lead to human flu, often resulting only in the production of antibodies in the blood. If transmission does cause human flu, it is called zoonotic swine flu. People with regular exposure to pigs are at increased risk of swine flu infection.
Around the mid-20th century, identification of influenza subtypes became possible, allowing accurate diagnosis of transmission to humans. Since then, only 50 such transmissions have been confirmed. These strains of swine flu rarely pass from human to human. Symptoms of zoonotic swine flu in humans are similar to those of influenza and of influenza-like illness in general, namely chills, fever, sore throat, muscle pains, severe headache, coughing, weakness and general discomfort.
In August 2010, the World Health Organization declared the swine flu pandemic officially over.
Cases of swine flu have been reported in India, with over 31,156 positive test cases and 1,841 deaths till March 2015.
Signs and symptoms:
According to the Centers for Disease Control and Prevention (CDC), in humans the symptoms of swine flu are similar to those of influenza and of influenza-like illness in general. Symptoms include fever, cough, sore throat, body aches, headache, chills and fatigue. The 2009 outbreak has shown an increased percentage of patients reporting diarrhea and vomiting.
Because these symptoms are not specific to swine flu, a differential diagnosis of probable swine flu requires not only symptoms but also a high likelihood of swine flu due to the person’s recent history. For example, during the 2009 swine flu outbreak in the United States, CDC advised physicians to “consider swine influenza infection in the differential diagnosis of patients with acute febrile respiratory illness who have either been in contact with persons with confirmed swine flu, or who were in one of the five U.S. states that have reported swine flu cases or in Mexico during the 7 days preceding their illness onset.” A diagnosis of confirmed swine flu requires laboratory testing of a respiratory sample (a simple nose and throat swab)……click & see
Influenza viruses bind through hemagglutinin onto sialic acid sugars on the surfaces of epithelial cells; typically in the nose, throat and lungs of mammals and intestines of birds (Stage 1 in infection figure).
Swine flu in humans:
People who work with poultry and swine, especially people with intense exposures, are at increased risk of zoonotic infection with influenza virus endemic in these animals, and constitute a population of human hosts in which zoonosis and reassortment can co-occur. Transmission of influenza from swine to humans who work with swine was documented in a small surveillance study performed in 2004 at the University of Iowa. This study among others forms the basis of a recommendation that people whose jobs involve handling poultry and swine be the focus of increased public health surveillance. The 2009 swine flu outbreak is an apparent reassortment of several strains of influenza A virus subtype H1N1, including a strain endemic in humans and two strains endemic in pigs, as well as an avian influenza.
The CDC reports that the symptoms and transmission of the swine flu from human to human is much like that of seasonal flu. Common symptoms include fever, lethargy, lack of appetite and coughing, while runny nose, sore throat, nausea, vomiting and diarrhea have also been reported. It is believed to be spread between humans through coughing or sneezing of infected people and touching something with the virus on it and then touching their own nose or mouth. Swine flu cannot be spread by pork products, since the virus is not transmitted through food. The swine flu in humans is most contagious during the first five days of the illness although some people, most commonly children, can remain contagious for up to ten days. Diagnosis can be made by sending a specimen, collected during the first five days, to the CDC for analysis.
The swine flu is susceptible to four drugs licensed in the United States, amantadine, rimantadine, oseltamivir and zanamivir; however, for the 2009 outbreak it is recommended it be treated under medical advice only with oseltamivir and zanamivir to avoid drug resistance. The vaccine for the human seasonal H1N1 flu does not protect against the swine H1N1 flu, as they are antigenically very different.
The cause of the 2009 swine flu was an influenza A virus type designated as H1N1. In 2011, a new swine flu virus was detected. The new strain was named influenza A (H3N2)v. Only a few people (mainly children) were first infected, but officials from the U.S. Centers for Disease Control and Prevention (CDC) reported increased numbers of people infected in the 2012-2013 flu season. Currently, there are not large numbers of people infected with H3N2v. Unfortunately, another virus termed H3N2 (note no “v” in its name) has been detected and caused flu, but this strain is different from H3N2v. In general, all of the influenza A viruses have a structure similar to the H1N1 virus; each type has a somewhat different H and/or N structure.
Complications Of Swine Flu And Higher Risk Individuals:-
Those at higher risk include those with the following:
*Age of 65 years or older
*Chronic health problems (such as asthma, diabetes, heart disease)
Complications (for all patients but especially for those at higher risk) can include:
1. A respiratory sample collected within the first five days of illness will be collected.
2. The sample is sent to the CDC for laboratory analysis and confirmation.
At this time the CDC is recommending the use of oseltamivir (Tamiflu) or zanamivir (Relenza) for treatment and/or prevention of Swine flu.
Why is swine flu now infecting humans?
Many researchers now consider that two main series of events can lead to swine flu (and also avian or bird flu) becoming a major cause for influenza illness in humans.
First, the influenza viruses (types A, B, C) are enveloped RNA viruses with a segmented genome; this means the viral RNA genetic code is not a single strand of RNA but exists as eight different RNA segments in the influenza viruses. A human (or bird) influenza virus can infect a pig respiratory cell at the same time as a swine influenza virus; some of the replicating RNA strands from the human virus can get mistakenly enclosed inside the enveloped swine influenza virus. For example, one cell could contain eight swine flu and eight human flu RNA segments. The total number of RNA types in one cell would be 16; four swine and four human flu RNA segments could be incorporated into one particle, making a viable eight RNA-segmented flu virus from the 16 available segment types. Various combinations of RNA segments can result in a new subtype of virus (this process is known as antigenic shift) that may have the ability to preferentially infect humans but still show characteristics unique to the swine influenza virus . It is even possible to include RNA strands from birds, swine, and human influenza viruses into one virus if a single cell becomes infected with all three types of influenza (for example, two bird flu, three swine flu, and three human flu RNA segments to produce a viable eight-segment new type of flu viral genome). Formation of a new viral type is considered to be antigenic shift; small changes within an individual RNA segment in flu viruses are termed antigenic drift and result in minor changes in the virus. However, these small genetic changes can accumulate over time to produce enough minor changes that cumulatively alter the virus’ makeup over time (usually years).
Second, pigs can play a unique role as an intermediary host to new flu types because pig respiratory cells can be infected directly with bird, human, and other mammalian flu viruses. Consequently, pig respiratory cells are able to be infected with many types of flu and can function as a “mixing pot” for flu RNA segments . Bird flu viruses, which usually infect the gastrointestinal cells of many bird species, are shed in bird feces. Pigs can pick these viruses up from the environment, and this seems to be the major way that bird flu virus RNA segments enter the mammalian flu virus population.
Present vaccination strategies for SIV control and prevention in swine farms, typically include the use of one of several bivalent SIV vaccines commercially available in the United States. Of the 97 recent H3N2 isolates examined, only 41 isolates had strong serologic cross-reactions with antiserum to three commercial SIV vaccines. Since the protective ability of influenza vaccines depends primarily on the closeness of the match between the vaccine virus and the epidemic virus, the presence of nonreactive H3N2 SIV variants suggests that current commercial vaccines might not effectively protect pigs from infection with a majority of H3N2 viruses.
In response to requests from the U.S. Centers for Disease Control and Prevention, on April 27, 2009 the FDA issued Emergency Use Authorizations to make available diagnostic and therapeutic tools to identify and respond to the swine influenza virus under certain circumstances. The agency issued these EUAs for the use of certain Relenza and Tamiflu antiviral drugs, and for the rRT-PCR Swine Flu Panel diagnostic test.
The CDC recommends the use of Tamiflu (oseltamivir) or Relenza (zanamivir) for the treatment and/or prevention of infection with swine influenza viruses, however, the majority of people infected with the virus make a full recovery without requiring medical attention or antiviral drugs The virus isolates that have been tested from the US and Mexico are however resistant to amantadine and rimantadine. If a person gets sick, antiviral drugs can make the illness milder and make the patient feel better faster. They may also prevent serious flu complications. For treatment, antiviral drugs work best if started soon after getting sick (within 2 days of symptoms).
Some countries have issued orders to stockpile antivirals . These typically have an expiry date of five years after manufacturing.
To maintain a secure household during a pandemic flu, the Water Quality & Health Council recommends keeping as supplies food and bottled water, portable power sources and chlorine bleach as an emergency water purifier and surface sanitizer.
click & see Prevention of swine influenza has three components:-(1) prevention in swine, (2) prevention of transmission to humans, and (3) prevention of its spread among humans.
(1)Prevention in swine
Swine influenza has become a greater problem in recent decades as the evolution of the virus has resulted in inconsistent responses to traditional vaccines. Standard commercial swine flu vaccines are effective in controlling the infection when the virus strains match enough to have significant cross-protection, and custom (autogenous) vaccines made from the specific viruses isolated are created and used in the more difficult cases.
(2) Prevention of transmission to humans
There are antiviral medicines you can take to prevent or treat swine flu. There is no vaccine available right now to protect against swine flu. You can help prevent the spread of germs that cause respiratory illnesses like influenza by
*Covering your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
*Washing your hands often with soap and water, especially after you cough or sneeze. You can also use alcohol-based hand cleaners.
*Avoiding touching your eyes, nose or mouth. Germs spread this way.
*Trying to avoid close contact with sick people.
*Staying home from work or school if you are sick.
(3) Prevention of spread in humans
Recommendations to prevent spread of the virus among humans include using standard infection control against influenza. This includes frequent washing of hands with soap and water or with alcohol-based hand sanitizers, especially after being out in public. Vaccines against the H1N1 strain in the 2009 human outbreak are being developed and could be ready as early as June 2009.
Experts agree that hand-washing can help prevent viral infections, a surprisingly effective way to prevent all sorts of diseases, including ordinary influenza and the new swine flu virus. Influenza can spread in coughs or sneezes, but an increasing body of evidence shows little particles of virus can linger on tabletops, telephones and other surfaces and be transferred via the fingers to the mouth, nose or eyes. Alcohol-based gel or foam hand sanitizers work well to destroy viruses and bacteria. Anyone with flu-like symptoms such as a sudden fever, cough or muscle aches should stay away from work or public transportation and should see a doctor to be tested.
Social distancing is another tactic. It means staying away from other people who might be infected and can include avoiding large gatherings, spreading out a little at work, or perhaps staying home and lying low if an infection is spreading in a community.
Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.
A new study offers 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.
BLINDSIGHT A patient whose visual lobes in the brain were destroyed was able to navigate an obstacle course and recognize fearful faces subconsciously.
Scientists have previously reported cases of blindsight in people with partial damage to their visual lobes. This 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.
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, but also to subcortical areas. 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 patient 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.