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The anatomy of ancient Greece – Business Standard

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First Published: Wed, August 24 2022. 00:53 IST

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Anatomy 101: Is an ancient Chinese script the oldest anatomy textbook in existence? – SYFY WIRE

Hippocrates and Galen might come to mind when you think of classical anatomy, but someone might have figured the human body out before he ever did. Someone on the other side of the planet.

Anatomists who lived during Chinas Han Dynasty, a period when learning flourished, are thought to have first mapped the structure of the body (as opposed to function). Ancient scientists dissected bodies for thousands of yearsthe drawback is that too little evidence of it has surfaced, which explains why European texts have been the go-to for centuries. Medical scientist Vivien Shaw and her research team have now unearthed Chinese Mawangdui medical texts from some 2,200 years ago. That means the ghost of Hippocrates probably needs to take several seats.

The ancient Greeks and Chinese had some similar concepts, such as pneuma, or life force, which is broadly similar to Qi, Shaw, who recently published a study in The Anatomical Record, told SYFY WIRE. However, in Chinese medicine, the philosophy of yin and yang lies at the core of how the body is understood. There is nothing in ancient Greek medicine that matches this.

Long before the Renaissance brought on anatomical enlightenment in the Western world, discoveries made in China, Persia, and India reimagined how more ancient peoples may have previously thought of the human body. Some of them even predated the luminaries of ancient Greece and Rome. The Mawangdui texts do not directly mention acupuncture, but the knowledge they contain that is still used in the practice disproves erroneous thinking that acupuncture is not based on actual science. Not only are they factually comparable to anything that came out of ancient Greece, but they survived when several Greek texts perished in the fire that reduced the fabled Library of Alexandria to ashes.

Unearthed from the Mawangdui burial site, where they were hidden deep underground since 168 B.C., the Mawangdui manuscripts were placed along other artifacts associated with traditional Chinese medicine. This tomb also contained the body of the Lady of Dai, one of the most remarkable mummies in the world. Scientists are still unable to figure out how her body was preserved almost unnaturally well. Whether anything written in the Magwandui texts or others buried with them had something to do with thatremains unknown.

But how did the Chinese get around the Confucian tradition of venerating ancestors, which should have ultimately prevented them from carrying out dissections? This is really the only way they could have learned about the 11 (later 12) meridians, or energy pathways in the body, that form the basis for acupuncture. Later texts reveal that they used the bodies of criminals so they wouldnt have to break tradition and commit what would have been considered a sacrilegious act of disrespect.

There are instances in most of the meridians where the structures that the texts are describing can only be seen in the dissected body, and could not be inferred from looking at the exterior, Shaw explained. For example, there is no other method by which they could have known the vena cava travels through the abdomen on the right hand side. Careful, systematic dissection is required in order to find these structures, so they would have had to study the body in this way.

Pathways are associated with certain diseases much as humors were in medieval Europe. The Huangdi Neijing, or Yellow Emperors Canon of Internal Medicine, was the ultimate Chinese canon of medicine during the Han Dynasty, and within its revered pages are the oldest writings on acupuncture theory. This is because these teachings were actually copied from the earlier Mawangdui texts. While the Neijing itself appeared slightly later, the information inside that was gathered from the Mawangdui texts predates it. The Neijing has been copied and recopied to the present day to reflect advancements in medical knowledge up to this day.

The only difference between the Neijings original text on meridians and the Mawangdui texts is that a 12th meridian was later added to the Neijing. Both texts describe the circulation of Qi, or vital energy, through these meridians.

The location of the meridians and points has remained constant since the Neijing, Shaw said. Current research is trying to solve the mystery of why it is that, if you use this particular body map of meridians and points, you get the physiological changes and health benefits that you do. So, in a way, theancient texts have directly informed current research, even though themeridians and points were arrived at through looking at anatomy, not physiology.

Another mystery surrounding the Mawangdui texts is that they may not even be the oldest records of anatomy, just the oldest that have either survived or been discovered yet. There are thought to be older Eastern manuscripts that have so far eluded us. Maybe they will eventually be found by dissecting the past.

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Justice League Anatomy: The 5 Weirdest Things About Wonder Woman’s Body – CBR – Comic Book Resources

There are only a few beings in the DC Universe who are capable of making Batman scared. There are even fewer who have taken the blunt force trauma of an enraged Superman and lived to tell the tale. However, DC's most iconic female superhero, Wonder Woman, has done all that and more in comics, TV, and her own solo film in 2017.

DCs flagship Amazon has macked up quite an impressive list of accomplishments over the past eight decades. While a fair number of those feats involve her tools like the Lasso of Truth and her Invisible Jet, Diana Prince has accomplished just as much without them. Now, we're taking a closer look at Wonder Woman to see what makes her so much more than the dirt she was crafted from.

RELATED: How Thor Brought Wonder Woman's Mom into the Marvel Universe

While costumes may have changed over the years, one of the most consistent aspects of Diana's superhero moveset has been her strength. While it's measurements vary wildly depending on the stories it's appeared in, its worth noting that shes always stacked up to universe threatening enemies, and yes, Superman.

Her history includes repeatedly slugging it out with the Man of Steel, no small task for anyone in the realm of fiction. Her most auspicious task, however, was towing the entire Earth with Superman. While naysayers may cry foul at the idea that the weight was shared equally, even lifting a fraction of our planet would put in in DCs top 1% strength bracket.

Wonder Woman can't just dish out a beating. She can take one as well. Her history shows that she can survive being thrown into buildings, mountains, and the Earth itself without missing a beat. Her bracelets make deflecting projectiles a breeze, and her healing factor should render any injuries a moot point if anything ever manages to pierce her skin. Additionally, extreme temperatures dont act as anything more than an annoyance to her, as shes been shown in upper reaches of space without issue.

In Greg Rucka and Rags Morales' Wonder Woman #219, she fights Superman of all people, who flies into a rage believing Lois Lane was murdered by Doomsday in a plot by the devious Maxwell Lord. The icing on the cake is, of course, his belief that Diana is Doomsday, leading him to hold nothing back in his attempt to murder her. Not only does she best him in combat, but she does so while holding back as to not inflict lethal damage.

RELATED: Justice League Anatomy: 5 Weird Facts About Aquaman's Body

While she's not the fastest character on the Justice League roster, Wonder Woman has had her fair share of feats involving speed. She routinely is able to deflect bullets, which means that her reaction time sits in the nanoseconds since the average bullet travels at 1,700 mph.

Her pinnacle of speed would undoubtedly be her deflection of shards in Walter Simonson and Jerry Ordway's Wonder Woman #194, where shes forced to save a man from particles of a deity that number in the trillions raining in from across the universe. She deflects them long enough for several pantheons to arrive and assist her in defeating him.

One of Dianas lesser-known talents, the ability to speak any language is rarely mentioned when listing her skills. In her titular 2017 film, shes shown as easily switching between Ancient Sumerian, English, Spanish, Chinese, Greek, and French. The average human knows one to two languages, while exceptionally linguistic people can jump as high as 70. However, Diana is functionally capable of speaking any language on Earth. She is also capable of communication at a near-infinite level.

While that alone might be impressive, she's also capable of communicating with beings that aren't even people. In the aforementioned fight with Superman, she uses one of her even less frequently addressed abilities in animal communication to call up a flock of birds and assist her. She does this while mending a shattered wrist, so it's safe to assume even this level of communication requires little concentration from the Amazon.

Dianas most unique anatomical trait is that shes not human in the most technical sense. In some versions of her origin, she was constructed out of wet dirt. While it may not be her current origin, Dianas most iconic beginnings all extend from the idea she was crafted from clay.

In some versions of her origin, Diana was created from the clay of her homeland of Themyscira and given life by her mother Hippolyta, Queen of the Amazons. Dianas immaculate origin also has several other perks too. Since theres no genetic sequencing to mutate or alien physiology to decipher, many of her powers in this iteration come straight from their ancient source: the Greek pantheon of Olympian Gods. She was also given several traits from the Olympian deities, including being as "beautiful as Aphrodite, wise as Athena, swifter than Hermes, and stronger than Hercules" in some of her origin stories.

KEEP READING: Justice League Anatomy: The 5 Weirdest Things About Hawkman's Body

Dragon Ball Z Power Levels: The Strongest Fighter in the Series, Revealed

A content creator since 2005, Kai's work has netted several awards in the online community. From fiction to documentary, page or screen, you'll find much of his work covers a little bit of everything. Follow him on Instagram as @themediabay

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Nature up close: A giraffe’s anatomy is a study in superlatives – the tallest terrestrial animals on Earth, with a neck six feet long, and strong legs…

By "Sunday Morning" contributing videographer Judy Lehmberg.

I come from a pretty small family, so when my father married a South African woman with a large extended family, I was delighted. They are an interesting bunch: Russian Jews, some of whom survived the German concentration camps during World War II, and some like my step-mother's father, who fought in that war and lived to be 98 years old. Not long after I first met him, he asked me about the animals in Yellowstone National Park which they had visited on one of their trips to the U.S. He knew I was a biologist, so he asked where all the large animals were in the park.

I had to think a minute. Didn't he see the bison, elk, moose, pronghorn antelope, mule deer, two species of bears and the wolves? Yes, he said he say them, but where were the rest of them?

Then it hit me. Those are the only large animals in Yellowstone, and he was comparing them to his experiences in Kruger National Park and other African parks and reserves.

He was right. The continental U.S. has a measly 490 species of mammals, while Africa has 4,700. Granted the continent of Africa is huge by comparison, but that is almost ten times the number of mammal species than are in the U.S.

Africa has 90 species of antelope; the U.S. has zero. (Contrary to their name, American pronghorn are not true antelope.) We fair better in the bird department with a little more than 2,000 species in all of North America, which is similar to the total number in all of Africa. But Kenya alone has over 1,100 species, and Africa has the Sahara Desert where very few birds live full time. And then there are the strange-looking animals like elephants, rhinos, hippos and giraffes animals that are pretty difficult to explain strictly from an evolutionary standpoint. They all look like they were made by committees that couldn't agree on anything.

The giraffes are the most graceful of the "committee" species. They move almost as if they are trying to hold an invisible stack of books on their head. They aren't all that graceful-looking when they lean down to get a drink of water, but even just standing still and eating Acacia leaves, they seem to emit a graceful, peaceful air. How they eat those leaves is hard to understand when you notice the plant's three-inch-long thorns, but they don't seem to bother the giraffes a bit. They must have really tough tongues.

Their general anatomy is a study in superlatives. They are the tallest terrestrial animals on Earth. Even though they only have seven neck, or cervical, vertebra (the same as humans), their neck is six feet long and weighs 600 pounds. Their legs are six feet long, and their feet are 12 inches across, which along with strong leg bones helps them support their immense weight (in males, that's up to 3,000 pounds). Their heart is about two feet long and weighs around 25 pounds, and their lungs can hold up to 12 gallons of air.

Although males can be aggressive towards each other (more on that in a minute), they don't defend a territory or even live in consistent family groups. Sometimes a group of giraffes is all females and their young, sometimes they are all male, and sometimes the group is a mix of ages and both sexes. They are more fluid than many species, as group members tend to come and go from one group to another. No one seems to know what triggers them to move, or to return.

No one really knows why a giraffe's neck is so long. Before Charles Darwin proposed his theory of organisms inheriting characteristics (what we now know as genes) from their parents, some people thought animals acquired characteristics during their lifetimes and then passed those characteristics to their offspring. For several thousand years, that theory was believed by everyone from Hippocrates and Aristotle to, most famously, Jean-Baptiste Lamarck, and became known as "Lamarckian evolution." Lamarck used giraffes as an example. He believed they stretched their necks to reach higher leaves, and passed those stretched necks to their offspring. He was wrong. For many years biology teachers have taught that giraffes who happened to be born with slightly-longer necks could reach higher leaves, thereby outcompeting their shorter-necked friends and relatives and successfully pass those genes on to the next generation.

That may very well be true, as the fossil record shows giraffe necks have elongated, especially in the last seven million years. But it is virtually impossible to say why their necks got longer. Maybe it was because longer-necked individuals could reach higher leaves. But there could be at least one other explanation.

Male giraffes sometimes fight to win the right to mate with a female. They all fight the same way, by swinging their necks and hitting the other giraffe, usually trying to knock it off balance, causing it to fall, which can result in their death. They can also do a good bit of damage with their horns if a blow lands hard enough. I've never seen them fight to the death, but I have seen fights that lasted several minutes and didn't always have an obvious winner. Maybe males with longer, thicker necks are more successful at mating, and therefore pass those genes on to their offspring?

My favorite thing about giraffes is that they attract oxpeckers, birds that land on giraffes and other herbivorous animals in Africa, and pick parasites off them. I have no idea why, but oxpeckers seem particularly attracted to giraffes. I love to watch them run their beaks systematically through a giraffe's fur like a single-tinged comb, feeling for ticks and other parasites. Sometimes the giraffe will twitch its skin and the oxpeckers fly off, but sometimes they will hold their ears really still so an oxpecker can go in and grab whatever parasites are in there.

Judy Lehmberg is a former college biology teacher who now shoots nature videos.

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To watch extended "Sunday Morning" Nature videos click here!

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Nature up close: A giraffe's anatomy is a study in superlatives - the tallest terrestrial animals on Earth, with a neck six feet long, and strong legs...

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Anatomy and physiology of ageing 5: the nervous system – Nursing Times

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John Knight is senior lecturer in biomedical science; Yamni Nigam is associate professor in biomedical science, both at the College of Human Health and Science, Swansea University.

The nervous system controls the activities of all body organs and tissues, receiving input from sensory organs and responding via effector organs. With around 100billion interconnected neurons, the brain is an extremely complex, and still poorly understood, organ. However we do understand, to some degree, how age affects it, as well as the nervous system as a whole. This fifth article in our series on the anatomy and physiology of ageing describes the age-related changes occurring in the brain, spinal cord and peripheral nerves. These changes lead to a gradual decline in cognitive function and a range of other issues, such as reduced bladder control or postural hypotension, but in health the brain normally continues to function adequately throughout life.

Knight J, Nigam Y (2017) Anatomy and physiology of ageing 5: the nervous system. Nursing Times [online]; 113: 6, 55-58.

The nervous system, along with the endocrine system, controls and integrates the activities of all the bodys organs and tissues. It receives and processes sensory input from organs such as the eyes, ears and skin, and responds through a variety of effector organs.

The main organ of the nervous system is the brain, which, with around 100billion interconnected neurons, is extremely complex; despite decades of research, its function remains poorly understood. Ageing leads to a progressive loss of neurons and depletion of neurotransmitters (Mather, 2016), these changes are usually associated with a gradual decline in cognitive function and influenced by environmental, genetic and lifestyle factors (Nyberg et al, 2012).

The ageing brain gradually loses neurons and supporting neuroglial cells (Fig 1). Between the ages of 20 and 60, the brain loses around 0.1% of neurons per year, after which the process speeds up (Esiri, 2007). By the age of 90, brain mass will have decreased by around 11% compared with individuals in their 50s, which equates to a loss of about 150g of neural tissue (Wyss-Coray, 2016). The remaining tissues harbour an increased concentration of potentially harmful materials such as iron, aluminium and free radicals.

Aged neural tissues also show increasing pigmentation, largely due to the deposition of two pigments: one brown, lipofuscin (Ottis et al, 2012), and one black, neuromelanin (Clewett et al, 2016). Lipofuscin is linked to amyloid

protein deposition and the formation of neurofibrillary tangles. These abnormal areas of neural tissue are often present at low densities in aged brain tissue, even in the absence of disease (Wyss-Coray, 2016); however, where Alzheimers disease is present, these are at high densities.

The loss of neurons is most apparent in the cerebral cortex. The grooves (sulci) that mark the surface convolutions (gyri) of the cerebral cortex are visibly deeper in brains of older people (Fig 1). It was originally thought that the frontal lobes were particularly vulnerable to neural loss, but similar losses have been observed in other cortical regions such as the parietal lobes (Fjell et al, 2014).

Fig 1. Three age-related changes in the brain

Fig 1. Three age-related changes in the brain

Structural changes in the frontal and parietal lobes are related to poor memory. Many people in their 80s have modest levels of amyloid protein deposition and retain their memory, while individuals with higher levels typically have a poorer working (short-term) memory (Nyberg et al, 2012). However, the role of amyloid deposition in impairing memory has recently been questioned and other factors, such as accumulation of tau proteins, may play a more important role (Brier et al, 2016).

The hippocampus has a key role in memory and the acquisition of new skills. With age, it loses a significant amount of neural tissue (Burke and Barns, 2006), which may explain why activities such as learning a new language become more difficult with advancing age. Recent research indicated that navigating a computer-generated virtual environment improved spatial awareness and reduced the shrinkage of the hippocampus, both in younger and older people (Lvdn et al, 2012). Virtual reality computer programs could therefore potentially be used to reduce shrinkage in this vital brain area.

Around 35% of people over the age of 70years have gait problems; while there are many contributing factors, including age-related changes to muscles and joints, the nervous system is also implicated. The somatic motor cortex located in the frontal lobes of the brain controls the movement of muscles involved in walking. From middle age onwards the neurons in this region show signs of atrophy (Manini et al, 2013), which can contribute to gait problems, potentially reducing mobility in older people (Rosso et al, 2013).

Ageing is associated with a gradual increase in the size of the ventricles (fluid-filled chambers) in the brain (Fig 1). This is likely to result from a progressive loss of the cells that line the ventricles. Enlarged ventricles fill with more cerebrospinal fluid, and are readily observable using techniques such as magnetic resonance imaging. On average, the volume of the ventricular system increases by around 2.9% per year; this expansion appears to accelerate with age, with people over the age of 70 having a median rate of expansion of 4.25% per year (Raz and Rodrigue, 2006). Although ventricular expansion is seen in most older people, the cognitive impact of this remains unclear.

The medulla oblongata and other areas of the brainstem lose fewer neurons than other regions of the brain. The brainstem is probably the best preserved region of the brain, which probably reflects its essential role in supporting life: it controls breathing, peristalsis, heart rate and blood pressure. However, the autonomic function of the brain does decline with age and this can compromise the bodys ability to respond quickly to internal and external environmental changes (Hotta and Uchida, 2010). Both branches of the autonomic nervous system (ANS) the parasympathetic and sympathetic branches are compromised with age (Parashar et al, 2016).

These changes can negatively affect older people. For example, the blunting of baroreceptor responses increases the risk of postural hypotension, so standing up suddenly can lead to falls and injury. Another negative consequence is the gradual loss of bladder control. To control micturition, the body relies on the interplay of sensory stretch receptors and the ANS (which together monitor bladder filling) and the conscious areas of the cerebral cortex (which signals when the bladder is full). To initiate micturition, the body needs motor control of the urinary sphincter. All these elements function less well with age, and these age-related changes combine with those in other body systems such as prostate enlargement in men and weakened pelvic floor muscles in women to reduce bladder sensitivity and control (Hotta and Uchida, 2010), which can lead to continence problems.

Cerebral blood flow decreases by around 0.38% per year, equating to a 27% decline over 70years of life (Chen et al, 2011). This is a direct consequence of the age-related changes in the cardiovascular system, and may be exacerbated in patients with atherosclerotic occlusion of the carotid arteries.

The blood-brain barrier (BBB) is formed primarily of tight junctions between adjacent endothelial cells within the blood vessels in the brain. Additionally, specialised neuroglial cells called astrocytes wrap around the cerebral vessels, forming a further physical barrier between the blood and neural tissues. The BBB is essential to prevent most pathogens and many toxic materials crossing into the neural networks and pathways of the brain, but its integrity appears to diminish with age. A recent study indicates that, during normal ageing, the BBB is first weakened in the hippocampus, thereby allowing harmful substances and pro-inflammatory mediators to cross into this vital region of learning and memory. This breaching of the BBB may contribute to hippocampal shrinkage, and therefore to cognitive decline (Montagne et al, 2015).

Ageing is associated with a declining production of many neurotransmitters, including noradrenaline, glutamate, dopamine and serotonin. The decline in dopamine appears to be particularly important: dopamine modulates motor function and the acquisition of new skills, while also acting as one of the brains reward chemicals (Mather, 2016). The number of dopamine-producing neurons decreases as part of the normal ageing process, and this can adversely affect the ability to learn from past experiences. Recent studies show that many older people who boosted their levels of dopamine by taking L-DOPA (a drug normally used to treat Parkinsons disease) were learning as quickly as young adults again (Chowdhury et al, 2013).

Few studies have examined age-related changes to the spinal cord. A recent animal-model study shows an increase of cholesterol content in the ageing spinal cord, and the authors suggest this may potentially impair cord function (Parkinson et al, 2016).

Age-related changes to neurons and neuroglial cells appear to have little effect on spinal cord function. However, age-related changes to the vertebrae and intervertebral discs may increase pressure on the spinal cord and its branching nerve roots. This can slow down the conduction of nerve impulses along motor neurons, contributing to reduced muscular strength (Manini et al, 2013). Reduced sensory and motor conduction will increase the risk of injury due to poor coordination, poor balance and poor fine motor control.

With age, some peripheral neurons show a dying back (shrinkage of axonal length), loss of mitochondria and a degeneration of their insulatory myelin sheaths. Some of this damage may be caused by a rise in the concentrations of pro-inflammatory mediators in the body. The ageing body becomes less effective in clearing toxic metabolites and, as peripheral nerves are not afforded the protection of the BBB, this may contribute to peripheral nerve damage (Manini et al, 2013).

The loss of myelin slows the conduction of peripheral nerve impulses by around 5-10% (Joynt, 2000). In health, this reduction in conductivity causes few problems, but in older people with diabetes it may contribute to, and exacerbate, diabetic neuropathy. Damaged peripheral nerves are not repaired as efficiently in older people as in their younger counterparts, and some of these nerves are never repaired. This can contribute to reduced sensation and motor control.

In the absence of disease, intellectual ability can be retained throughout life. However, the gradual loss of neurons, depletion of neurotransmitters and slowing of nerve conduction may act together to slow down the processing of information. As a result, older people may take longer to complete certain tasks, and commonly experience the functional brain changes described below.

The loss of short-term and episodic memory is probably the earliest indication of age-related changes in the brain. Unlike what happens in dementia, the loss of short-term memory in the absence of disease does not affect life skills (such asthe ability to cook), but manifests as inconveniences (such as forgetting an item from the shopping list). Episodic memory (that is, remembering autobiographical events and their timings and sequence) also gradually declines in many older people (Fjell et al, 2014).

Verbal communication skills generally remain strong throughout life (Park and Reuter-Lorenz, 2009), but people over the age of 70years may have increasing problems using or recalling words. The ability to quickly name a common object usually remains stable up to the age of 70, but then declines with advancing years (Harada et al, 2013).

The progressive loss of neurons, reduction in impulse velocity and minor changes in the spinal cord lead to a slowing down of reaction times (Spirduso, 1995). This can create problems, particularly when a fast reaction is essential (for example, to step out of the way of oncoming traffic).

In England, around 22% of men and 28% of women over the age of 65 are affected by depression; in care homes, the figures are even greater, with around 40% of residents affected (Age UK, 2017).

It is almost impossible to determine whether depression in older people occurs as a normal consequence of ageing or as a result of chemical imbalances seen in types of depression that also affect younger people. Concentrations of neurotransmitters involved in lifting mood (particularly serotonin) diminish with age and this can contribute to symptoms of depression (Fidalgo et al, 2013). The Royal College of Psychiatrists estimates that >85% of depressed older people receive no help from the NHS (Age UK, 2017). Depression can often produce symptoms that mimic dementia (pseudo-dementia) and this often causes great anxiety.

On the whole, older people are less prone to emotional outbursts than younger people. This may be related to the relative structural stability of some of the brain regions linked to emotions. Most studies of the amygdalae which are heavily involved in impulsive behaviours and emotional reactions reveal little evidence of atrophy or shrinkage at a much slower rate than in other brain regions. Additionally, the amygdalae also appear to retain most of their functional activity in older age (Mather, 2016).

Because the overall neural mass reduces with age, neuroactive drugs such as antidepressants and neuroleptics can be more potent in older people. Doses normally prescribed to adults may induce confusion or delirium, and may therefore need to be adjusted.

How normal age-related changes to the brain can be distinguished from pathological changes associated with dementia (for example, Alzheimers disease) is hotly debated. The problem is that three of the main clinical features of Alzheimers disease loss of episodic memory, loss of brain tissue and amyloid deposition are also seen in apparently healthy older people with little or no evidence of dementia. However, it is generally recognised that the main risk factor for developing dementia is advancing age (Fjell et al, 2014).

Unlike cells in many other parts of the human body, most neurons do not undergo cell division so, when they dieas a result of age or injury, they are generally not replaced. Fortunately, the brain contains over 100billion interconnected neurons (the connectome) and many researchers agree that it has an in-built redundancy, known as the brain reserve. This is defined as the physical resources of the brain in terms of brain mass and number of neurons; a larger brain reserve is often associated with better outcomes after brain injury and in various neurological diseases (Tucker and Stern, 2011).

The brain reserve is not necessarily a good predictor of cognitive function (many people with normal cognition have significant brain atrophy), so the concept of cognitive reserve has emerged. People with a high cognitive reserve are able to use their brain reserve more efficiently to perform tasks, and this seems to happen through increased efficiency of functional connections between neurons (Marques et al, 2016).

Good predictors of a high cognitive reserve include high education level, high IQ, highly complex occupation and large amount of social interaction. Recent research indicates that cognitive ability may also be maintained by neural compensation, a process in which new circuits of neurons are recruited to perform tasks that were once carried out by aged ordamaged neural pathways (Steffener and Stern, 2012). In normal ageing, the brain reserve does decline but cognition ismaintained thanks to the brains in-built redundancy.

Keeping mentally active throughout life can reduce the effects of age on the nervous system (Mahncke et al, 2006), and engaging in social, sporting and mentally challenging activities can slow downthe decline in cognitive performance (Nyberg et al, 2012). It appears the more intellectually demanding and complex an individuals occupation, the better their cognitive performance in later years; however, in retirement, when the mental challenges of work are removed, this effect appears to decline.

Older people should be encouraged to engage in stimulating activities such as socialising, reading and games, which are thought to improve cognitive function and memory, as well as reduce the riskof depression. It is a common misconception that ageing naturally leads to conditions such as confusion, dementia and delirium. The human brains in-built redundancy allows it to adequately cope with the physical changes associated with ageing. Indeed, in the absence of disease, adequate mental function can be retained throughout life.

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Anatomy and physiology of ageing 5: the nervous system - Nursing Times

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The New ABCs of Medical School: Anatomy, Biochemistry, and Cooking – Food Tank (blog)

As Hippocrates, the founder of modern medicine, spoke, Let food be thy medicine. However, most medical schools in the United States do not adequately teach nutrition. Several programs, including at Tulane University, are addressing this shortcoming by including cooking classes in their curriculum. The hope is that by teaching future doctors how to cook delicious and healthy meals, they will pass that knowledge on to their patients, improving long-term health.

The rates of obesity and obesity-related diseases are increasing throughout the world according to Prediabetes: A Worldwide Epidemic. The Center for Disease Control reports that nearly half of all deaths in the United States are due to heart attacks, strokes, and diabetes. Entire scientific journals, such as Nutrition and Health, Diabetes, and the Journal of Nutrition, are devoted to examining the relationships between nutrition and health. Research has shown that nutrition is one of the leading causes of and significantly affects the management of diabetes, cardiovascular disease, and aging-related diseases.

There is no clear correlation between policy recommendations and nutrition choices. For example, a study that provided nutrition information to adults at fast-food chains found that simply providing information did not alter consumer choices. Coaching has consistently proven effective at changing eating habits, especially when tailored to an individuals lifestyle and medical history. Many see using doctors as nutrition coaches as a natural extension of a physicians duties and a valuable opportunity for one-on-one intervention. However, a National Institute of Health survey revealed that a majority of primary care physicians do not give diet advice. According to polls reported by the Washington Post, less than 25 percent of doctors feel they are informed enough regarding nutrition to discuss it knowledgeably.

Tulanes program was developed in 2014 to better instruct medical students in nutrition. According to their website, Through hands-on cooking classes, medical students and physicians learn the practical aspects of lifestyle change necessary to help them guide their patients to healthier choices.

The National Academy of Sciences recommends 25 hours of nutrition instruction for medical students, whereas the Tulane course requires 53 hours of culinary classes, 53 hours clinical care teaching, and 53 hours learning nutritional counseling strategies in lifestyle modification. Researchers at Tulane examined the effectiveness of the program and found improvements to the lifestyle of medical participants and significant health benefits to diabetic patients, including improved HbA1c, blood pressure, and cholesterol levels.

To date, 28 other medical schools, two residency programs, and two nursing schools have adapted the Tulane curriculum. Dartmouth, the University of Chicago, the University of Massachusetts, and others have started similar programs within their medical schools. Harvard University partnered with the Culinary Institute of America to offer week-long workshops that have demonstrated improvements in attendees ability to advise patients as well as ameliorating their lifestyle, including cooking more at home, making healthier food choices like whole grains and nuts, and heightened awareness of calorie consumption.

Personally taking culinary classes can improve peoples diets without making a trip to the doctor. Programs in Chicago improve nutrition knowledge and vegetable consumption in children. Community kitchens in Peru taught adolescents and improved their diets. Similar kitchens in Canada have had a similar effect of improving lifestyles and education within several communities. In general, public health researchers find that cooking at home can significantly improve health when the knowledge of good nutrition is applied. For some of the Tulane programs recipes, click here.

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The New ABCs of Medical School: Anatomy, Biochemistry, and Cooking - Food Tank (blog)

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