Growing old artistically

The creation of art requires a complex interplay between brain and body. Indeed, the appearance of a finished piece is intimately linked to both the subjective experiences and mental processes of the artist. Scientists are beginning to appreciate how art can be used to study changes in body and mind as individuals age. This research is opening new doors in both our understanding of the ageing process and the way we diagnose and treat age-related disorders.

The ageing body:

Arguably a painter’s most important tool is vision. Unfortunately, it is commonplace for vision to deteriorate with advancing age. This deterioration can lead to a decrease in colour and contrast discrimination, increased glare and a decreased field of view. Perceptual changes such as these will all affect the way an artist perceives the world, an effect which can be observed through changes in their artistic style and composition. Take Monet for example. As he grew older, Monet developed severe cataracts in both eyes. By the age of 65 this disorder was already affecting his visual acuity and colour vision. He could no longer perceive a vivid colour pallete, instead seeing the world as desaturated and yellow. This change was reflected in his art. Monet painted a series of canvases depicting water lilies in the gardens of his home town, Giverny. The changes in his visual perception can be seen in the two images below showing the same scene painted prior to and following development of cataracts.

Monet: Lilys at Giverny before cataracts
Monet: Lilys at Giverny before cataracts
Same scent after development of cataracts
Same scene after development of cataracts

The ageing eye also often suffers from changes in its optical media – the fluid filling the eye ball, hardening and yellowing of its lens and a decrease in pupil size. These changes all reduce the amount of light which eventually reaches the retina at the back of the eye. Indeed, it is estimated that by age 60 the retina will be receiving only one third of the light a 20 year-old eye would have received. Overall, these changes reduce an individual’s ability to distinguish fine detail and cause a shift in colour vision towards the red end of the visual spectrum. An example of this can be seen in the later work of artists such as Rembrandt. Notice the lack of detail and shift to a yellowed pallete in his later works.

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Rembrandt early self portrait
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Later work

Another disorder of the ageing body which has a notable affect on artistic output is arthritis. This reduces dexterity and movement, leading to less detailed work often with larger brush strokes.

The ageing brain:

The separate elements of an artistic composition are as broad and variable as the artist’s own mind. Scientists have found that certain artistic styles can be linked to different regions of the brain. And that damage to these regions can dramatically change an artist’s style. An example of such change can be seen in ageing individuals suffering from Alzheimer’s disease. Alzheimer’s sufferers experience a loss of visuospatial skills, due to degeneration of their posterior parietal and temporal cortices*. This means that sufferers’ artwork becomes progressively more abstract and less spatially precise. However, at least in the disease’s earlier stages, this does not necessarily diminish the artistic appeal of their work. Although pieces may lose spatial precision this is often replaced with an appealing sense of colour and form. For example, work by the artist Carolus Horn can be seen to alter significantly as his Alzheimer’s progressed, becoming more two-dimensional and less detailed. However, alongside these changes his work also became more vibrant and developed a simplistic charm.

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Carolus Horn: Prior to disease onset
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Post Alzheimer’s

Unfortunately as the disease progresses further the sufferers’ artistic deficits become more acute, until finally images bear no resemblance to their intended subject.

Interestingly, in certain forms of dementia (especially frontotemporal dementia (FTD) with degeneration of the left anterior temporal lobe) some individuals develop artistic talents which were not present before disease onset. Many of these patients develop a compulsive need to paint, repeating the same picture many times. These compulsions may explain how patients can become relatively accomplished in a short space of time.

The study of changing artistic style in patients with degenerative dementias is giving scientists a valuable insight into how their brains function. Indeed, this area of research may one day open up a range of novel diagnostics and therapeutic interventions.

However, perhaps the most poignant observation made in recent years is the effect art can have on the lives of patients and their families. Some families have found that art represents a way to communicate with loved ones who have long since lost the ability to communicate verbally. Sufferers also benefit from focusing on their artistic strengths. This gives patients a feeling of accomplishment they previously lacked and, in some cases, can provide temporary relief from their symptoms. Art seems to have the ability to improve the quality of life for dementia sufferers and their families, whilst also offering an amazing insight into the working of their minds. Therefore, it’s great to see new research focusing on this area and organisations such as the Hilgos foundation emerging, who offer grants for art students working with Alzheimer’s patients.

Post by: Sarah Fox

* Posterior parietal regions are important for perception of space and appreciation of movement in space and time, while temporal areas are required for perception of form and depth.

Neuro-warfare

Although chemical and biological warfare has been internationally condemned since the 1600s, scientific research has continued to uncover chemicals which can have a devastating effect on the nervous system. Indeed, at the end of last year there were reports of an alleged government attack on civilians using an unidentified nerve gas in the city of Homs in Syria.  It is thought that Assad’s regime have been developing and stockpiling chemical weapons. If this is true, the situation shows disturbing similarity to Saddam Hussein’s use of the nerve gases against Iranian civilians during the Gulf War in the 1980s.

Interestingly, the discovery of nerve gases was made more or less by accident. The organophosphate (OP) family of nerve gases, including sarin and tabun, were being studied by German scientist Dr. Gerhard Schrader during the 1930s as possible insecticides. Whilst studying these chemicals Dr. Schrader accidentally spilled a drop of tabun onto the bench and, within minutes, was overwhelmed with dizziness and had difficulty breathing. It took him and his colleague three weeks to fully recover from this exposure.

By Mr.Henk [GFDL (http://www.gnu.org/copyleft/fdl.html) or CC-BY-SA-3.0-2.5-2.0-1.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons

OP nerve gases work by stopping the enzyme acetylcholinesterase (AChE) from breaking down the neurotransmitter acetylcholine (ACh). Normally, when ACh is released by nerve cells it is rapidly broken down by AChE, meaning that it can’t build up around target cells. However, when AChE stops working ACh collects around cells, overstimulating them. The effects are often seen as over-stimulation of muscle cells and glands which produce bodily fluids. After very high exposure to OP a victim will suffer a huge number of horrible symptoms, including, a runny nose, tight chest, blurred vision, shortness of breath, nausea, muscle spasms, drooling, crying, incontinence, vomiting and abdominal pain. In this case, death usually follows quickly, either due to choking or from suffocation caused by overstimulation of the diaphragm. Sarin was infamously used by the Japanese terrorist group Aum in an attack in a Tokyo subway station in 1995, which killed 13 and left thousands with temporary vision problems.

Another family of chemicals that affect the nervous system are anti-cholinergics.  Anticholinergics stop ACh from activating receptors on target cell (muscles and glands).  As a result, these chemicals have almost entirely the opposite effect to OP nerve gases. The symptoms include a dry mouth, muscle weakness, blurred vision, as well as hallucinations and some pretty strange delirious behaviour. Anticholinergics could have a potential (though still illegal) use as a ‘non-lethal’ weapon to incapacitate people – since people can’t really fight back if they’re delirious. Saddam Hussein was accused of stockpiling the anticholinergic Agent 15 to use in the Persian Gulf War against Kurds and Iranians. Another similar chemical known as BZ was weaponised by the U.S. military during the Cold War. Thankfully, stocks were uncovered and destroyed before it was deployed. BZ was also discovered by accident by a scientist innocently working on digestive disorders.

By: Staff Sgt. Steve Faulisi, U.S. Air Force [Public domain], via Wikimedia Commons

Despite some of these examples, where dangerous biological weaponry has emerged from otherwise benign research; there would be no sense in avoiding all scientific research in the fear that someone might accidentally stumble across the next weapon of mass destruction. Scientists certainly have a duty to be aware of the potential uses for their work, especially since research is (or should be) freely accessible online. However, ceasing research into potentially hazardous chemicals altogether would inhibit some pretty important discoveries; especially since many chemicals which are beneficial in small doses, could have a lethal ‘dual-use’. Indeed, drugs which inhibit AChE are not just potential biological weapons, they are also currently the most widely used treatment for Alzheimer’s disease.

Perhaps, since the discovery of the occasional nasty seems unavoidable if important biological research is to continue, the best course of action would be to fund counter research into possible treatments.

At the University of Sheffield, Prof. Mike Blackburn and his collaborators have recently developed a ‘bioscavenger’ to mop up OP chemicals, preventing them from attaching to AChE. This kind of treatment will hopefully help save lives in the event of nerve agent attacks. Last year, Dr. Moshe Goldsmith at the Weizmann Institute in Israel mutated a human liver enzyme so that it could break down OP nerve gas molecules. While this research holds obvious benefits to humanity, the implications of this work also raises an ethical dilemma. If the gene code for this newly-evolved enzyme could be put into soliders, we could be faced with a scenario where armies can be genetically manipulated to become immune to chemical or biological weapons. Unfortunately, this hypothetically amazing feat of science could result in an biological arms race…a situation it’s hard to envisage anyone winning.

The Arts and Humanities Research Council has a Neuroscience Ethics Network that bring together researchers from all over the UK. Some of this article has been based on prospective lectures initiated by the Network, intended for undergraduate Neuroscience students. If you’d like to read more about the Network, please click here: http://www.lab.ls.manchester.ac.uk/neuroethicseducation/

Post by Natasha Bray

The Science of Sleep – You snooze you lose?

My top ten favourite things to do are as follows:

1) Eatsleep and food
2) Sleep
3) Snack
4) Snooze
5) Lunch
6) Nap
7) Chow down
8) Dream
9) Pig out
10) Have a kip.

Now, I know why I like to eat – food tastes good. Also, if we’re going to be all ‘sciencey’ about it, humans have evolved to enjoy eating as we need the nutrition to survive. But why do we sleep? The answer is no one really knows. However, anyone who has ever pulled an ‘all nighter’, suffered insomnia or done a PhD can tell you sleep is certainly necessary. A lack of sleep leads to difficulty concentrating, an inability to focus and a lack of motivation which gets progressively worse the less sleep you get. And the only way to rectify this? To get some sleep.

It’s tempting to assume that we sleep to save energy, but this isn’t really the case. In fact we don’t save that much energy sleeping compared to just laying still. However, one thing we do know is that sleep is actually vital for the brain. That would explain the difficulty concentrating when you don’t get enough of it.

dog sleepingThere are two main types of sleep: rapid eye movement (REM), which is when we have our most unusual disjointed dreams and non-rapid eye movement sleep (NREM) which usually brings fewer, more mundane, dreams. Unsurprisingly you can tell when someone is in REM sleep because their eyes dart around, whilst the eyes are relatively still in NREM sleep. Throughout the night we cycle in and out of these sleep stages (around 2-4 cycles every night), with the vast majority of sleep comprised of NREM. Scientists can monitor what stage of sleep people are in by looking at their brain wave (EEG) activity.

Yes, apparently brain waves are an actual thing. I’m not trying to be funny here – I genuinely had no idea these were real until earlier this week. I thought it was a saying like ‘being on the same wavelength’. Who knew? Everybody else in the world it would seem.

When brain cells want to communicate with each other they use electro-chemical signals which can be detected by neighbouring cells. Brain waves are simply the combined ‘firing’ of groups of brain cells. This collective ‘firing’ creates a voltage change large enough to be detected by electrodes placed on the scalp and this is the basis of the EEG. Peaks of synchronised firing are generally followed by periods of silence before moving to another peak, forming rippling electrical waves – brain waves.

During REM sleep brain waves are low amplitude, which means fewer cells are synchronised therefore producing a smaller signal. Waves which do occur in REM are also fast, meaning the cells are firing off electrical pulses more frequently. This pattern is very similar to the EEG signal seen when we’re awake.

Fun fact about REM: Species of animals with larger brains seem to require a higher percentage of REM sleep compared to NREM sleep. With tit-bits like that you’re sure to have as many friends as me! Two’s a lot right?

Anyway, REM is thought to be important for forming new spatial memories (like remembering how to get to that new bakery in town which sells those gorgeous pastries). Scientists also think that REM sleep may be required for the development of new brain cells in the memory forming region of the brain (the hippocampus). This is one of the processes which may be necessary for laying down new memories. woman sleepinh

NREM sleep can be broken down into three stages. During the first stage, a state somewhere between sleep and wakefulness, brain wave activity starts to slow and switches to the high amplitude slow waves which characterise NREM sleep. During the second stage ‘spindles’ can appear. These are groups of large amplitude, irregular spikes in the EEG. It is thought that this high-amplitude activity represents periods when large areas of the brain are synchronised. This may be the perfect time for memories to be transferred between brain regions and may facilitate the incorporation of new memories into older existing ones. Interestingly schizophrenics show less spindle activity, but like many aspects of sleep, it isn’t really clear why. In the final stage, the brain has fully switched into slow wave. It is thought that during this stage new memories form. Slow wave activity is linked with the ability of brain cells to make new connections and ‘prune’ out old ones.

There is so much that absolutely no one understands when it comes to sleep. All in all I think this makes this topic incredibly interesting and, yeah I’m just going to say it – exciting. Ultimately though I’m quite happy that scientific research has unquestionably disproved the phrase ‘you snooze, you lose’.

Post by: Liz Granger

Twitter: @Bio_Fluff

References

Roth TC 2nd, Rattenborg NC, Pravosudov VV. (2010) The ecological relevance of sleep: the trade-off between sleep, memory and energy conservation. Philos Trans R Soc Lond B Biol Sci 27;365(1542):945-59.

Fogel S, Martin N, Lafortune M, Barakat M, Debas K, Laventure S, Latreille V, Gagnon JF, Doyon J, Carrier J (2012). NREM Sleep Oscillations and Brain Plasticity in Aging. Front Neuro, 3:176

Saletin, J.M.; Goldstein, A.N.; Walker, M.P (2011). The Role of Sleep in Directed Forgetting and Remembering of Human memories. Cerebral Cortex21, 2534–2541

Ferrarelli, F.; Huber, R.; Peterson, M.J.; Massimini, M.; Murphy, M.; Riedner, B.A.; Watson, A.; Bria, P.; Tononi, G. (2007). Reduced Sleep Spindle Activity in Schizophrenia Patients. The American Journal of Psychiatry164, A62