Study maps how brain recognise extensively varied faces at one go

December 27, 2016

Washington, Dec 27: Ever wondered how can you recognise whether your friend is happy or sad, at a glance? Also how can you recognise a friend, even if you haven't seen him/her in a decade?

BrainAnswering to all these, a recent study finds out how the brain recognise familiar faces with efficiency and ease, despite extensive variation in how they appear.

Researchers at Carnegie Mellon University in the US are closer than ever before to understand the neural basis of facial identification.

The study, published in the journal of Proceedings of the National Academy of Sciences (PNAS), used highly sophisticated brain imaging tools and computational methods to measure the real-time brain processes that convert the appearance of a face into the recognition of an individual.

“Our results provide a step towards understanding the stages of information processing that begin when an image of a face first enters a person's eye and unfold over the next few hundred milliseconds, until the person is able to recognize the identity of the face," said study author Mark D. Vida.

To determine, how the brain rapidly distinguishes faces, they researchers scanned the brains of four people using magnetoencephalography (MEG).

MEG allowed them to measure ongoing brain activity throughout the brain on a millisecond-by-millisecond basis while the participants viewed images of 91 different individuals with two facial expressions each: happy and neutral.

The participants indicated that when they recognised that the same individual's face was repeated, regardless of expression.

The MEG scans allowed the researchers to map out, for each of many points in time, which parts of the brain encode appearance-based information and which encode identity-based information.

The team also compared the neural data to behavioral judgments of the face images from humans, whose judgments were based mainly on identity-based information.

Then, they validated the results by comparing the neural data to the information present in different parts of a computational simulation of an artificial neural network that was trained to recognise individuals from the same face images.

“Combining the detailed timing information from MEG imaging with computational models of how the visual system works has the potential to provide insight into the real-time brain processes underlying many other abilities beyond face recognition," said another researcher David C. Plaut.

The researchers are hopeful that the findings might be used in the near future to locate the exact point at which the visual perception system breaks down in different disorders and injuries, ranging from developmental dyslexia to prosopagnosia or face blindness.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
Agencies
May 10,2020

Washington D.C., May 9: Do the middle age feel much stressful now, and seems to have changed over time, if compared to the life in the 90s? Well, this recent study indicates that it might be true.

The study has signalled to the fact that life may become more stressful majorly for middle-aged people than it was in the 1990s. The researchers reached this analysis even before the novel coronavirus started sweeping the globe.

A team of researchers led by Penn State found that across all ages, there was a slight increase in daily stress in the 2010s compared to the 1990s. But when researchers restricted the sample to people between the ages of 45 and 64, there was a sharp increase in daily stress.

"On average, people reported about 2 percent more stressors in the 2010s compared to people in the past," said David M. Almeida, professor of human development and family studies at Penn State.

"That's around an additional week of stress a year. But what really surprised us is that people at mid-life reported a lot more stressors, about 19 percent more stress in 2010 than in 1990. And that translates to 64 more days of stress a year."

Almeida said the findings were part of a larger project aiming to discover whether health during the middle of Americans' lives has been changing over time.

"Certainly, when you talk to people, they seem to think that daily life is more hectic and less certain these days," Almeida said.

For the study, the researchers collected data from 1,499 adults in 1995 and 782 different adults in 2012.

Almeida said the goal was to study two cohorts of people who were the same age at the time the data was collected but born in different decades. All study participants were interviewed daily for eight consecutive days.

During each daily interview, the researchers asked the participants about their stressful experiences throughout the previous 24 hours.

They asked questions related to arguments with family or friends or feeling overwhelmed at home or work, so and so. The participants were also asked how severe their stress was and whether those stressors were likely to impact other areas of their lives.

"We were able to estimate not only how frequently people experienced stress, but also what those stressors mean to them," Almeida said.

"For example, did this stress affect their finances or their plans for the future. And by having these two cohorts of people, we were able to compare daily stress processes in 1990 with daily stress processes in 2010," Almeida added.

After analyzing the data, the researchers found that participants reported significantly more daily stress and lower well-being in the 2010s compared to the 1990s.

Additionally, participants reported a 27 percent increase in the belief that stress would affect their finances and a 17 percent increase in the belief that stress would affect their future plans.

Almeida said he was surprised not that people were more stressed now than in the 90s, but at the age group that was mainly affected.

"We thought that with economic uncertainty, life might be more stressful for younger adults. But we didn't see that. We saw more stress for people at mid-life," Almeida said.

"And maybe that's because they have children who are facing an uncertain job market while also responsible for their own parents. So it's this generational squeeze that's making stress more prevalent for people at mid-life," he concluded.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
Agencies
June 30,2020

Between 30-40 per cent of deaths from studies in intensive care units from different countries are people with diabetes, said Paul Zimmet, Professor of Diabetes, Monash University, Australia.

Zimmet, who is President International Diabetes Federation, added that the actual mechanism as to why COVID-19 may cause diabetes is as yet unknown, however, several possibilities exist. "COVID-19 is a very destructive and cunning virus and causes terrible damage to tissues including the lungs and pancreas," said Zimmet. Below are excerpts from an exclusive chat with IANS.

Why do you say Diabetes is dynamite if a person has been infected with COVID-19?

There have been many deaths in many countries, e.g. Italy, China, the UK and US among people with diabetes after infection with COVID-19 (SARS-Cov-2).

The mortality tends to be mainly in older Type 2 diabetics. Between 30-40 per cent of deaths from studies in intensive care units from different countries are people with diabetes. This outcome and other complications from the virus, particularly pneumonia, are more likely in people with diabetes which is poorly controlled with high blood sugars (poor metabolic control).

Diabetes is often associated with other chronic conditions, including obesity, hypertension and heart disease compounding the risk. These latter conditions all convey higher risk to COVID-19 infections.

ACE-2, which binds to SARS-Cov-2 and allows the virus to enter human cells is also located in organs and tissues involved in glucose metabolism. Is there solid evidence that virus after entering tissues may cause multiple and complex impairment of glucose metabolism?

The actual mechanism as to why COVID-19 may cause diabetes is as yet unknown.

However, several possibilities exist. Firstly, COVID-19 is a very destructive and cunning virus and causes terrible damage to tissues, including the lungs and pancreas.

A new study just published showed that in miniature lab-grown pancreas, and other cells such as liver, made using human stem cells, COVID-19 caused destruction of the pancreas beta cells that produce insulin.

It is possible that the virus causes disruption of the cells by disrupting cellular metabolism. This is possibly the way it brings about new-onset diabetes. ACE-2 exists in high concentration in the lung as this also explains the terrible lung side effects of COVID-19 infections.

Can COVID-19 lead to a new mechanism of diabetes? Probably a new form of diabetes or a new form of disease?

The COVID-19 virus has only been with us for about 5 months and there is a huge amount that we still must learn about its cunning and devastating ways. The purpose of the Global COVIDIAB Diabetes Registry, a joint initiative of Monash University in Australia, and King’s College London is to gain a much better understanding of how common is the appearance of COVID-19 related diabetes, what form does it take be it type 1 or type 2 or a new form, and how common are the complications that we already know e.g. diabetic keto-acidosis, hyperosmolar coma and high insulin requirements are causing high rates of ill health and mortality worldwide. The knowledge gained will aid our understanding for developing strategies to prevent and treat this terrible virus that has caused destruction globally.

Diabetes is one of the most prevalent chronic diseases in India. According to a recent study, sugar levels of diabetic persons increased by 20 per cent during nationwide lockdown in India to contain COVID-19 outbreak. Even after lockdown was lifted, many people are confined within their home. Do you think lack of physical activity will create more problems for diabetics?

My own major research has been on studying populations with high rates of diabetes, including ethnic Indian communities including India, Mauritius, and Fiji so I am very well aware of this. It is now well established that along with diabetes, that associated poor metabolic control of their diabetes places these people at the highest risk for COVID infection and its devastating complications and the associated morbidity and mortality. And these communities have high prevalence of heart disease as well.

Lockdown not only has deleterious effects on metabolic control of the diabetes through reduced opportunities for exercise to be protective serious consequences of SARS-CoV-2 infection, lockdown usually results in disruption of the regular medical care and the regular monitoring of metabolic control. This may also be partly due to the stress and poor compliance, or inability to afford their medications such as insulin. It may also be compounded by inability to access the care during the pandemic. Nevertheless, we now know that poor metabolic control heightens their risk as described above.

You have said diabetes is itself a pandemic just like Covid-19, and the two pandemics could be clashing. How could governments address this problem?

These are “The Times of COVID-19”. Most nations of the world were totally unprepared for a pandemic of this magnitude. They underestimated its potential impact and the destructive nature of the viral infection. This should prompt all countries to upgrade their guidelines to take into account the lessons learnt on infection control including training of staff specialising in infectious diseases and improved public education and taking their communities into their confidence about the terrible nature of COVID-19. The risks of COVID-19 infection need a much higher priority in the general community, particularly for people with chronic conditions such as diabetes, obesity, and cardiac conditions.

Governments are faced with chronic diseases (NCDs) like diabetes and communicable diseases (CDs) like viral and enteric diseases and TB. In general WHO gives the highest priority to communicable diseases and much less attention and funding to chronic diseases like diabetes (I was an adviser to WHO for many years (about 30) on diabetes and obesity and it was very frustrating to deal with this situation).

This attitude to diabetes, for example, has a flow down effect so that diabetes funding in countries by governments, rich and poor, suffered and was insufficient.

So now we have a COVID-19 pandemic and who are those at highest risk, yes people with diabetes and other NCDs, it is very important that now the two, Diabetes and COVID-19 are clashing face-to-face. This is a major issue that WHO and national governments have to face with equal priority’

Stressed people suffering from diabetes run a greater risk of poor blood glucose levels, what do you suggest to these people?

As mentioned in the answer above, stress is an important factor in upsetting the blood sugar (metabolic) control of diabetes. Additive to this is poor compliance with medications and diet. These and potential associated comorbidities due to other chronic conditions are part of the dynamic dynamite mixture.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.
Agencies
July 5,2020

The deadly coronavirus that entered India while there was still nip in the air has beaten rising mercury, humid conditions, unique Indian genome and has entered monsoon season with more potency as fresh cases are only breaking all records in the country.

India recorded a single-day spike of record 24,850 new coronavirus cases on Sunday, taking its total tally to 6.73 lakh corona-positive cases.

Top Indian microbiologists were hopeful in March that after the 21-day lockdown, as summer approaches, the rise in temperature would play an important role in preventing the drastic spread of COVID-19 virus in India.

Several virologists hinted that by June this year, the impact of COVID-19 would be less than what it appeared in March-April.

The claims have fallen flat as the virus is mutating fast, becoming more potent than ever.

According to experts, the novel coronavirus is a new virus whose seasonality and response to hot humid weather was never fully understood.

"The theory was based on the fact that high temperatures can kill the virus as in sterilisation techniques used in healthcare. But these are controlled environment conditions. There are many other factors besides temperature, humidity which influence the transmission rate among humans," Dr Anu Gupta, Head, Microbiologist and Infection Control, Fortis Escorts Heart Institute, told IANS.

There is no built-up immunity to COVID-19 in humans.

"Also, asymptomatic people might be passing it to many others unknowingly. New viruses tend not to follow the seasonal trend in their first year," Gupta emphasized.

Globally, as several countries are now experiencing hot weather, the World Health Organization (WHO) reported a record hike in the number of coronavirus cases, with the total rising by 2,12,326 in 24 hours in the highest single-day increase since COVID-19 broke out.

So far over 11 million people worldwide have tested positive for the disease which has led to over 5,25,000 deaths, according to data from Johns Hopkins University. The US remained the worst-hit country with over 28 lakh cases, followed by Brazil with 15.8 lakh.

According to Sandeep Nayar, Senior Consultant and HOD, Respiratory Medicine, Allergy & Sleep Disorders, BLK Super Speciality Hospital in New Delhi, whether temperature plays a role in COVID-19 infection is highly debated.

One school of thought said in the tropical regions of South Asia, the virus might not thrive longer.

"On the other hand, another school of thought has found that novel Coronavirus can survive in a hot and humid environment and tropical climate does not make a difference to the virus. According to them, this is what distinguishes the novel coronavirus from other common viruses, which usually wane in hot weather," stressed Nayar.

Not much has been studied in the past and no definite treatment or vaccine is available to date.

"Every day, new properties and manifestation of the disease come up. As of now, the only way to prevent this monster is by taking appropriate precautions. Hand hygiene, social distancing, cough etiquette and face masks definitely reduce spread of COVID-19 infection," Nayar told IANS.

Not just top Indian health experts, even Indian-American scientists had this theory in mind that sunshine and summer may ebb the spread of the coronavirus.

Ravi Godse, Director of Discharge Planning, UPMC Shadyside Pennsylvania in the US told IANS in April: "In the summer, the humidity can go up as well, meaning more water drops in the air. If the air is saturated with water and somebody sneezes virus droplets into such air, it is likely that the droplets will fall to the ground quicker, making them less infectious. So the short answer is yes, summer/sunshine could be bettera.

According to Dr Puneet Khanna, Head of Respiratory Medicine and Pulmonology, Manipal Hospital, Delhi, COVID-19 death rates are not too different in tropical countries but since the disease affected them late it was yet to show its peak in these areas.

"The virus can survive well in hot and humid countries and this is proven now," he stressed.

Comments

Add new comment

  • Coastaldigest.com reserves the right to delete or block any comments.
  • Coastaldigset.com is not responsible for its readers’ comments.
  • Comments that are abusive, incendiary or irrelevant are strictly prohibited.
  • Please use a genuine email ID and provide your name to avoid reject.