̽��ֱ�� of Cambridge - ̽��ֱ�� of New South Wales

Have we misunderstood post-traumatic stress disorder?

Anonymous — Fri, 19 Aug 2016 14:08:30 +0000

It’s long been assumed that war-related post-traumatic stress disorder (PTSD) stems from how well a person copes psychologically with exposure to violence or the threat of violence. A new study, published in the Academy of Management Journal, finds that this is only half the story, however.

̽��ֱ��researchers behind the study say that the context through which war is experienced – based on a person’s cultural, professional and organisational background – may be equally important in determining how warfare can be traumatic for some and not for others.

̽��ֱ��research focused on military doctors in Afghanistan, and found that the “dissonance” between what the medics experienced on the ground and their values as dedicated professionals resulted in “senselessness, futility and surreality” – factors that can lead to PTSD and other mental health problems.

“This understanding of the connection between PTSD and the context of those who suffer from it could change the way mental health experts analyse, prevent and manage psychological injury from warfare,” said Mark de Rond of ̽��ֱ�� of Cambridge Judge Business School, who co-authored the study with Jaco Lok of the ̽��ֱ�� of New South Wales Business School in Australia.

“ ̽��ֱ��study highlights the urgent and serious nature of dealing with PTSD – beyond the very real impact on many veterans, to others who work in the theatre of war, such as medical personnel,” says Lok.

Between 20 and 30 per cent of the 2.7 million US troops sent to Iraq or Afghanistan between 2001 and 2011 returned with some form of psychological injury, says the US Department of Veterans Affairs, while the British charity Combat Stress reported a four-fold increase in former service personnel seeking help for mental disorders in the past 20 years. In 2013, a former commander of Australian forces in the Middle East warned of a “large wave of sadness coming our way.”

̽��ֱ��new study is based on fieldwork by de Rond, Reader in Strategy & Organisation at Cambridge Judge Business School, who was “embedded” with a team of military surgeons at Camp Bastion in Afghanistan for six weeks in 2011 – and includes tales both harrowing and tragi-comic.

“ ̽��ֱ��doctors I was embedded with were known as Rear Located Medics, who don’t have a combat role, so they have less reason to fear for their lives than frontline personnel,” says de Rond. “Studying this group was an excellent way to look beyond psychological reaction to the horrors of warfare in order to also analyse contextual elements that lead to PTSD.”

For example, the Camp Bastion army medics were particularly disturbed by rules of the camp’s small 50-bed field hospital that required the quick transfer of badly mutilated children (often double amputees due to Improvised Explosive Devices encountered while playing) and other Afghan civilians to inferior local hospitals, often within 48 hours, to make way for new battlefield casualties. This was a specific, local organisational requirement.

“(It was) difficult for them to come terms with rules, practices and experiences on the ground that appeared contradictory to their purpose and values, thus amplifying feelings of senselessness,” the study says.

As an example of the surreal hopelessness faced by the medics, the study relates a conversation between two medics: “They talked about the frustration of bringing a stable, anesthetised patient over to some hospital only to be met by an empty van, having to hand over a wired-up patient to someone with no equipment at all.”

This practice tore at the fabric of their professional purpose and responsibility and highlighted the contrast between the medics’ actual experience in a warfare setting with their professional expectations as doctors – a life of “the meaningful, the good and the normal.”

̽��ֱ��doctors’ real names are not used, but the study instead substitutes the names of characters such as “Trapper,” “Hawkeye” and “Potter” from the hit TV show “M*A*S*H”. Among de Rond’s field notes chronicled in the study, some incidents seem like they could have come out of the “M*A*S*H” gallows-humour playbook:

“One of the theatre nurses told me of an experience over Easter weekend, when a double amputee had come in… One of his legs had come off, and (the nurse) was asked to please take it to the mortuary (and from there to the incinerator). As he crossed the ambulance bay carrying a yellow (container) with a leg, he ran into the Commanding Officer and a TNC (Travel Nurse Corps) nurse walking the other way, dressed in bunny ears and carrying Easter eggs.”

Such a contrast “between the human gravity of the situation on the one hand, and the casual nature of everyday rituals and routines on the other” can have a very disorienting effect, the study says.

When such disorientation is sustained over time, it can also permanently damage the ability of everyday rituals and routines to provide a sense of meaning and predictability to life back home. This may be one important reason why many war veterans find it so difficult to adjust back to home life.

Camp Bastion, which was constructed in 2005 and handed over to Afghan forces in 2014, was the largest British overseas military camp since World War II, accommodating 32,000 people. ̽��ֱ��field hospital was staffed by mostly British and American doctors, with some Danes and Estonians, many of them “battle-hardened” by previous deployments to other war zones such as Bosnia and Sierra Leone.

Reference:
Mark de Rond and Jaco Lok. ‘Some things can never be unseen: the role of context in psychological injury at war.’ Academy of Management Journal (2016). DOI: 10.5465/amj.2015.0681

Adapted from a Cambridge Judge Business School press release.

In understanding war-related post-traumatic stress disorder, a person’s cultural and professional context is just as important as how they cope with witnessing wartime events, which could change the way mental health experts analyse, prevent and manage psychological injury from warfare.

This understanding of the connection between PTSD and the context of those who suffer from it could change the way mental health experts analyse, prevent and manage psychological injury from warfare.

Mark de Rond

Defence Images

Soldiers Patrolling in Afghanistan

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

Yes

Licence type:

Attribution-ShareAlike

New insights into the dynamics of past climate change

sc604 — Wed, 14 Oct 2015 07:05:16 +0000

A new study of the relationship between ocean currents and climate change has found that they are tightly linked, and that changes in the polar regions can affect the ocean and climate on the opposite side of the world within one to two hundred years, far quicker than previously thought.

̽��ֱ��study, by an international team of scientists led by the ̽��ֱ�� of Cambridge, examined how changes in ocean currents in the Atlantic Ocean were related to climate conditions in the northern hemisphere during the last ice age, by examining data from ice cores and fossilised plankton shells. It found that variations in ocean currents and abrupt climate events in the North Atlantic region were tightly linked in the past, and that changes in the polar regions affected the ocean circulation and climate on the opposite side of the world.

̽��ֱ��researchers determined that as large amounts of fresh water were emptied into the North Atlantic as icebergs broke off the North American and Eurasian ice sheets, the deep and shallow currents in the North Atlantic rapidly slowed down, which led to the formation of sea ice around Greenland and the subsequent cooling of the Northern Hemisphere. It also strongly affected conditions in the South Atlantic within a matter of one to two hundred years. ̽��ֱ��results, published in the journal Nature Geoscience, show how climate events in the Northern Hemisphere were tightly coupled with changes in the strength of deep ocean currents in the Atlantic Ocean, and how that may have affected conditions across the globe.

During the last ice age, which took place from 70,000 to 19,000 years ago, the climate in the Northern Hemisphere toggled back and forth between warm and cold states roughly every 1000 to 6000 years. These events, known as Dansgaard-Oeschger events, were first identified in data from Greenland ice cores in the early 1990s, and had far-reaching impacts on the global climate.

̽��ֱ��ocean, which covers 70% of the planet, is a huge reservoir of carbon dioxide and heat. It stores about 60 times more carbon than the atmosphere, and can release or take up carbon on both short and long timescales. As changes happen in the polar regions, they are carried around the world by ocean currents, both at the surface and in the deep ocean. These currents are driven by winds, ocean temperature and salinity differences, and are efficient at distributing heat and carbon around the globe. Ocean currents therefore have a strong influence on whether regions of the world are warm (such as Europe) or whether they are not (such as Antarctica) as they modulate the effects of solar radiation. They also influence whether CO2 is stored in the ocean or the atmosphere, which is very important for global climate variability.

“Other studies have shown that the overturning circulation in the Atlantic has faced a slowdown during the last few decades,” said Dr Julia Gottschalk of Cambridge Department of Earth Sciences, the paper's lead author. “ ̽��ֱ��scientific community is only beginning to understand what it would mean for global climate should this trend continue, as predicted by some climate models.”

Analysing new data from marine sediment cores taken from the deep South Atlantic, between the southern tip of South America and the southern tip of Africa, the researchers discovered that during the last ice age, deep ocean currents in the South Atlantic varied essentially in unison with Greenland ice-core temperatures. “This implies that a very rapid transmission process must have operated, that linked rapid climate change around Greenland with the otherwise sluggish deep Atlantic Ocean circulation,” said Gottschalk, who is a Gates Cambridge Scholar. Best estimates of the delay between these two records suggest that the transmission happened within about 100 to 200 years.

Digging through metres of ocean mud from depths of 3,800 metres, the team studied the dissolution of fossil plankton shells that was closely linked to the chemical signature of different water masses. Water masses originating in the North Atlantic are less corrosive than water masses from the South Atlantic.

“Periods of very intense North Atlantic circulation and higher Northern Hemisphere temperatures increased the preservation of microfossils in the sediment cores, whereas those with slower circulation, when the study site was primarily influenced from the south, were linked with decreased carbonate ion concentrations at our core site which led to partial dissolution,” said co-author Dr Luke Skinner, also from Cambridge's Department of Earth Sciences.

To better understand the physical mechanisms of rapid ocean adjustment, the data was compared with a climate model simulation which covers the same period. “ ̽��ֱ��data of the model simulation was so close to the deep ocean sediment data, that we knew immediately, we were on the right track,” said co-author Dr Laurie Menviel from the ̽��ֱ�� of New South Wales, Australia, who conducted the model simulation.

̽��ֱ��timescales of these large-scale adjustments found in the palaeoceanographic data agree extremely well with those predicted by the model. “Waves between layers of different density in the deep ocean are responsible for quickly transmitting signals from North to South. This is a paradigm shift in our understanding of how the ocean works,” said Axel Timmermann, Professor of Oceanography at the ̽��ֱ�� of Hawaii.

Although conditions at the end of the last ice age were very different to those of today, the findings could shed light on how changing conditions in the polar regions may affect ocean currents. However, much more research is needed in this area. ̽��ֱ��study's findings could help test and improve climate models that are run for both past and future conditions.

̽��ֱ��sediment cores were recovered by Dr Claire Waelbroeck and colleagues aboard the French research vessel Marion Dufresne.

̽��ֱ��research was supported by the Gates Cambridge Trust, the Natural Environmental Research Council of the UK, the Royal Society, the European Research Council, the Australian Research Council and the National Science Foundation of the United States of America.

Reference:
Gottschalk, J et. al. Abrupt changes in the southern extent of North Atlantic Deep Water during Dansgaard-Oeschger events. Nature Geoscience (2015). DOI: 10.1038/ngeo2558

A new study finds that changing climate in the polar regions can affect conditions in the rest of the world far quicker than previously thought.

Other studies have shown that the overturning circulation in the Atlantic has faced a slowdown during the last few decades. ̽��ֱ��scientific community is only beginning to understand what it would mean for global climate should this trend continue, as predicted by some climate models

Julia Gottschalk

Left: Marine sediment core sample from the South Atlantic with fossilised partially dissolved shells of planktonic organisms. Right: Well-preserved plankton shells.

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

Yes