How Brain Perceives the World and analyses the Sight

Scientists gain new insight into how brain perceives the world

London, Oct 2, 2015 (PTI)

Neuroscientists have gained new insight into how the brain perceives the world by using high resolution high field MRI to study activity in different layers of the visual cortex in great detail.
The visual cortex is the part of the brain that processes sight by receiving feedforward input from the eyes.

But feedback is also required from parts of the brain that conceptualise and contextualise in order for us to fully comprehend what we are seeing.

Scientists have so far been impeded by the integration of both signals within the six different layers of the cortex.

Researchers at the University of Glasgow have come up with a solution by taking advantage of the fact that input from the retina is mapped out in the visual cortex, the University said in a release.

Much like light entering the lens of a camera hits a specific portion of a sensor to form a pixel, so too light entering the eye has a corresponding portion in the visual cortex, which when applied to magnetic resonance images, is called a voxel.

In order to study the feedback signal, the researchers showed subjects a picture – for example a car – part of which was obscured by a white square.

This enabled them to identify and isolate the area of the brain that responded only to the occluded portion of the scene, and thus quieten the feed-forward signal.

But even in the absence of sensory input, the visual cortex communicates with other brain areas.

By measuring the activity in this part, the researchers were able to see where feedback and feed-forward activity took place across the six different layers of the cortex as the brain tried to complete the picture by inferring what the whole scene looked like.
The ability to measure layer specific signals in humans was made possible by 7 Tesla MRI techniques pioneered at the University of Minnesota's Center for Magnetic Resonance Research.

Professor Essa Yacoub and colleagues have developed techniques that allow visualisation of human brain activity at sub-millimeter spatial resolutions and with high degrees of accuracy.

Such a capability was previously only possible with invasive studies in animals.
The result, published in the journal Current Biology, reveals the layered cortical organisation of external versus internal processing streams during perception, with activity during normal visual stimulation peaking in mid-layers and contextual information peaking in superficial layers.

Professor Lars Muckli, of the Institute of Neuroscience & Psychology, said: "Understanding the brain's feedback system is important if we are to develop more powerful computers and artificial intelligence systems, but it might also help us to better understand mental illnesses such as schizophrenia and autism.

Successful Life - Inherent Controls

Successful in Life - Inherent Controls

Once a small boy asked his father about an illustration for a success in life.
His father took him to the river front. En route to the river, they purchased a kite and long string. The colourful kite was flown. Soon the length of the string was insufficient as the kite flew long and high.

Then the boy, asked - Papa - if we cut off the string or leave the string, the kite could fly higher? Why don't we do this?

Father agreed to this proposal and let him leave the string. The kite flew little higher and the descent started gradually. Within no time, the kite drifted away and fell at an obscure place.

Then the father went on to narrate:
Success in life is similar to this kite. It is tethered by a long string called
1) Family, Friends and Affection
2) Values
3) Morality and Ethics
4) Personal Intergrity and Honesty (to name a few).

Many a time, it seems that we could reach higher planes, if we are not restrained by this string. However, the drift will not last long. And the life would be at Jeopardy.

Hence, it is better to be tethered by the string of values rather than drift away without accountability, for temporary inducement or adhoc benefits which could ruin the future.

Vegetarian diet may help lower your BP

Tokyo, Feb 25, 2014 (PTI):

Vegetarians rejoice! Eating a vegetarian diet may lower your blood pressure (BP), a long-term research has claimed.

Factors such as diet, body weight, physical activity and alcohol intake play a role in the risk of developing hypertension, researchers said.

Dietary modifications have been shown to be effective for preventing and managing hypertension, according to research author Yoko Yokoyama, of the National Cerebral and Cardiovascular Center, Osaka, Japan, and colleagues.

The authors analysed seven clinical trials and 32 studies published from 1900 to 2013 in which participants ate a vegetarian diet.

Net differences in BP associated with eating a vegetarian diet were measured, researchers said.

In the trials, eating a vegetarian diet was associated with a reduction in the average systolic (peak artery pressure) and diastolic (minimum artery pressure) BP compared with eating an omnivorous (plant and animal) diet.

In the 32 studies, eating a vegetarian diet was associated with lower average systolic and diastolic BP, compared with omnivorous diets.

"Further studies are required to clarify which types of vegetarian diets are most strongly associated with lower BP. Research into the implementation of such diets, either as public health initiatives aiming at prevention of hypertension or in clinical settings, would also be of great potential value," researchers said.

The research was published in the journal JAMA Internal Medicine..

Sindhoor - Originally it is Bixa Orellana Dye

Sindhoora

Traditional Dye of Red Shade

We, in Indian culture, have come across the word Sindhura at many places.

Sindhura is a beautiful shade of red, which is the popular context. In North India, it is mostly used by women to apply on the top of the forehead. 

(At times, Kunkuma (Vermillion) is also referred as Sindhoor in North India. However, it is made by mixing Picking Lime to the Turmeric Powder.)

While procuring large quantity of Sindhura, for a temple inauguration, we got the complete picture of Sindhura trade and Manufacturing process currently followed in the market. 

It is made from lead, which Pb₃O_4,

Lead Tetroxide is its chemical name. It is basically used by the Paint and Glass industry.​ Due to cheaper ingredients and commercial mass usage, this procedure is followed. In long term and regular usage/ higher quantity this can be carcenogenic. This is also called Miniun. http://en.wikipedia.org/wiki/Lead(II,IV)_oxide ​

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However, earlier days - the flower and seeds of Sindur tree were used. Even now, it is an art. Kindly refer to these two documents in the end of this article.

This is called Bixa Orellana (Tree). The natural dye is harmless. Every Hanuman Temple should be using this herbal powder instead of the harmful chemical.

Indigenous usage in many parts of the continent, including Nepal, is reflective of our customs. Check the photo from Brazil.

http://tasteofnepal.blogspot.in/2013/06/sindur-tree-of-nepal-sindure.html?m=1

https://www.academia.edu/4918901/Formulation_and_Evaluation_of_Herbal_Sindoor_Using_Different_Natural_Herbal_Ingredients

Hence, follow safe practices whether at home or temples. We should not save at the cost of health. Spread awareness.

Musical Training in Younger days, Helps a lot

Scientists have found some of the strongest evidence yet that musical training in younger years can prevent the decay in speech listening skills in later life.

According to a new Canadian study led by the Rotman Research Institute (RRI) at Baycrest Health Sciences, older adults who had musical training in their youth were 20% faster in identifying speech sounds than their non-musician peers on speech identification tests, a benefit that has already been observed in young people with musical training.

The findings are published in The Journal of Neuroscience.

Among the different cognitive functions that can diminish with age is the ability to comprehend speech. Interestingly, this difficulty can persist in the absence of any measurable hearing loss. Previous research has confirmed that the brain's central auditory system which supports the ability to parse, sequence and identify acoustic features of speech -- weakens in later years.

Starting formal lessons on a musical instrument prior to age 14 and continuing intense training for up to a decade appears to enhance key areas in the brain that support speech recognition. The Rotman study found "robust" evidence that this brain benefit is maintained even in the older population.

"Musical activities are an engaging form of cognitive brain training and we are now seeing robust evidence of brain plasticity from musical training not just in younger brains, but in older brains too," said Gavin Bidelman, who led the study as a post-doctoral fellow at the RRI and is now an assistant professor at the University of Memphis.

"In our study we were able to predict how well older people classify or identify speech using EEG imaging. We saw a brain-behaviour response that was two to three times better in the older musicians compared to non-musicians peers. In other words, old musicians' brains provide a much more detailed, clean and accurate depiction of the speech signal, which is likely why they are much more sensitive and better at understanding speech."

Bidelman received a GRAMMY Foundation research grant to conduct the study and partnered with senior scientist Claude Alain, assistant director of Baycrest's RRI and a leading authority in the study of age-related differences in auditory cortical activity.

The latest findings add to mounting evidence that musical training not only gives young developing brains a cognitive boost, but those neural enhancements extend across the lifespan into old age when the brain needs it most to counteract cognitive decline. The findings also underscore the importance of music instruction in schools and in rehabilitative programs for older adults.

In this study, 20 healthy older adults (aged 55-75) -- 10 musicians and 10 non-musicians -- put on headphones in a controlled lab setting and were asked to identify random speech sounds. Some of the sounds were single vowel sounds such as an "ooo" or an "ahhh," others more ambiguous as a mix of two sounds that posed a greater challenge to their auditory processing abilities for categorizing the speech sound correctly.

During the testing cycles, researchers recorded the neural activity of each participant using electroencephalography (EEG). This brain imaging technique measures to a very precise degree the exact timing of the electrical activity which occurs in the brain in response to external stimuli. This is displayed as wave forms on a computer screen. Researchers use this technology to study how the brain makes sense of our complex acoustical environment and how aging impacts cognitive functions.

According to Bidelman and Alain's published paper, the older musicians' brain responses showed "more efficient and robust neurophysiological processing of speech at multiple tiers of auditory processing, paralleling enhancements reported in younger musicians."

Teixobactin - Next Generation Anti-Biotic

A newly discovered antibiotic eliminates pathogens without encountering any detectable resistance, a finding that may lead to treatments for chronic infections such as tuberculosis and MRSA.

For years, pathogens' resistance to antibiotics has put them one step ahead of researchers, which is causing a public health crisis, according to Northeastern University Distinguished Professor Kim Lewis.

The pioneering work to develop a novel method for growing uncultured bacteria led to the discovery of the antibiotic, called Teixobactin, and Lewis' lab played a key role in analysing and testing the compound for resistance from pathogens.

Lewis said this marks the first discovery of an antibiotic to which resistance by mutations of pathogens have not been identified.

The research team says teixobactin's discovery presents a promising new opportunity to treat chronic infections caused by staphylococcus aureus, or MRSA, that are highly resistant to antibiotics, as well as tuberculosis, which involves a combination of therapies with negative side effects.

Lewis and biology professor Slava Epstein tapped into a new source of antibiotics beyond those created by synthetic means: uncultured bacteria, which make up 99 per cent of all species in external environments.

They developed a novel method for growing uncultured bacteria in their natural environment.
Their approach involves the iChip, a miniature device Epstein's team created that can isolate and help grow single cells in their natural environment and thereby provides researchers with much improved access to uncultured bacteria.

Researchers have since assembled about 50,000 strains of uncultured bacteria and discovered 25 new antibiotics, of which Teixobactin is the latest and most interesting, Lewis said.

The antibiotic was discovered during a routine screening for antimicrobial material using this method.

Lewis then tested the compound for resistance development and did not find mutant MRSA or Mycobacterium tuberculosis resistant to teixobactin, which was found to block several different targets in the cell wall synthesis pathway.

"Our impression is that nature produced a compound that evolved to be free of resistance. This challenges the dogma that we've operated under that bacteria will always develop resistance. Well, maybe not in this case," Lewis said.

However, indiscriminate usage of anti-biotics without monitoring/ awareness/ prescription could render this drug ineffective as well.  So, use Anti- Biotics Judiciously.