How to grow your brain

brainblog

When it comes to the brain, it seems that bigger is better. Neurogenesis is the term scientists use to refer to the production of new brain cells, called ‘neurons’. It was once thought that neurogenesis only occurred prenatally, such that you were born with all of the brain cells that you would ever have. However, since the 1980s there has been growing consensus that a few specific regions of the brain continue to produce new brain cells throughout life, a process known as ‘adult neurogenesis.’ Importantly, several healthy lifestyle choices centred on diet and exercise can increase this mechanism and appear to benefit the mind.

Although the purpose of these new neurons is not yet fully understood, a portion of these cells appear to become functionally integrated into areas of the brain essential for learning and memory processes. Some researchers hypothesise that young neurons increase the amount of storage space for memories, while others believe that these cells improve the storage mechanism for ‘encoding’ information, in such a way that memories are more accurately and easily remembered.

Adult neurogenesis has been demonstrated in several animal species, including rodents, birds, monkeys and humans. Manipulating neurogenesis by pharmacologically inhibiting the production of new brain cells or alternatively by using treatments to promote production has been shown to directly affect the cognitive performance of several species.  For example, mice and rats with reduced neurogenesis have difficulty with spatial navigation, recognising a previously encountered object and drawing associations between events that are separated by a time delay, analogous to the causal link between lightening and thunder.  All of these cognitive processes rely on an area of the brain called the ‘hippocampus’, which is one of the regions where neurogenesis continues into adulthood, and is often thought of as the memory centre of the brain.

In humans, reductions in neurogenesis may contribute to conditions such as depression and Alzheimer’s disease. It is hypothesised that increased neurogenesis may underlie the benefits of anti-depressant medication that improve mood and several treatments designed to help patients suffering from memory loss.  Luckily, there are several easy ways to increase the production of new brain cells and to protect the ones you have.

The most effective ways to enhance neurogenesis include exercise and eating less. Providing mice with running wheels doubles the number of new neurons that their brains produce. Similarly, humans participating in aerobic exercise a few times each week show patterns of brain activity suggestive of increased cell production. Importantly, in both mice and humans, exercise induced neurogenesis is associated with improved cognitive performance. These beneficial effects of exercise on neurogenesis and cognition are also seen when daily food consumption is reduced. In rodents and humans, reducing food intake by 30% each day has been shown to increase cell production and improve memory in just a few months.

It is also important to acknowledge that not all new brain cells survive long enough to become functionally integrated and useful. Fortunately, there are other behaviours, along with exercise and restricting food consumption that increase the survival of brain cells. These beneficial behaviours include reducing stress levels, getting sufficient sleep and continuing to actively engage your mind through new experiences and education. All of these behaviours protect brain cells and prevent age-related memory loss, while also having countless benefits on overall health.

If you needed one more reason to live a healthy lifestyle, know that by eating well and exercising, you will be helping to grow your brain.

*Brianne Kent [2011] is doing a PhD in Experimental Psychology. Picture credit: ddpavumba and http://www.freedigitalphotos.net.

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The health threats of a sedentary lifestyle

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“Doing some physical activity is better than doing none.” (10 facts on physical activity, World Health Organization)

While the benefits of physical activity have long been recognised, the threats of inactivity have been exacerbated by modernity. Not only have modern technological advances made it possible for less physical exertion to take place, but the general increase in life expectancy has also opened the flood gate for a series of chronic (non-communicable) diseases. Lack of physical activity detrimentally increases several risk factors for chronic disease and death, including raised blood levels of lipids, glucose, as well as high blood pressure. Inactive people are more likely to develop obesity, diabetes, cardiovascular disease (heart disease and stroke), osteoporosis and some cancers (breast and bowel), all of which pose major public health problems. Interestingly, evidence emerges concerning the link between low activity and a greater risk of dementia, depression and impaired physical function in the elderly. Convincing research suggests that sedentary behaviour has harmful health effects independent of physical activity, meaning that high levels of activity don’t cancel out the effects of sitting down for extended periods of time.

Physical activity can be pursued in four ‘domains’ of daily life including leisure time, work, transport and at home. They act on health independently through different pathways. For my PhD research, I am using data from epidemiological studies led by the Medical Research Council (MRC) Epidemiology Unit in Cambridge and collaborators to accurately assess activity levels in adult populations in order to examine the interplay between different activity domains (especially leisure and work) and health. Another fascinating aspect on which I am trying to shed some light is the importance of the dimension of activity for a given health outcome. In short, what matters more: overall energy expenditure (total calories you burn) or time spent at various intensity levels (how hard you work).  Some of the studies that I have drawn from are: EPIC, Fenland, InterAct and National Survey for Health and Development. The world-class expertise of the MRC Epidemiology Unit lies in its development of novel technologies for the objective assessment of physical activity, such as waterproof monitors that are easy to wear and collect information on heart rate and body acceleration. These devices have opened up new research avenues which enable a much more accurate estimation of activity than questionnaires. Building on these results, my work seeks to contribute to these studies which provide the high quality means for informing future public health policy and practice.

The societal burden from physical inactivity is manifested as a growing healthcare budget and a loss of productivity. According to the World Health Organization (WHO), insufficient physical activity is the fourth leading risk factor for mortality and causes 6% of deaths worldwide. In 2008, there were 5.3 million deaths due to physical inactivity, which is equal to the number of deaths from smoking. Intriguingly, research has shown that a failure to spend 15-30 min/day in activity of moderate intensity shortens people’s lifespan by three to five years.

Global physical activity surveillance efforts based on questionnaires have shown that 31% of adults worldwide are physically inactive, highlighting the pandemic proportion of this behaviour.  However, investigators on the National Health and Nutrition Examination Survey in the USA used accelerometers and showed that more than 95% of American adults fail to meet physical activity guidelines. With an aging global population, the elderly represent the fastest growing group, which is also the least active and has the highest risk for developing chronic disease. Therefore, promoting physical activity in later life is an important approach to help those individuals achieve healthful aging, thereby mitigating the risk of disease and perhaps even slowing the aging process.

How much activity?

How active do we have to be? According to the current guidelines by American Heart Association and American College of Sports Medicine, a minimum 30 minutes/day of moderate-intensity activity (e.g. brisk walking) five days per week, or 20 minutes of vigorous activity (e.g. jogging) three days per week, or a combination of the two should be performed to maintain health and reduce the risk of chronic disease. Sedentary behaviour should be reduced and activities to maintain or increase muscular strength and flexibility should also be performed at least two times a week. In order to prevent unhealthy weight gain, adults should engage in 60 minutes of moderate-to-vigorous activity every day. Those wishing to sustain weight loss need to participate in 60-90 minutes of moderate-to-vigorous activity daily without exceeding calorific intake.

In the context of chronic disease prevention and health promotion, physical inactivity has not been given as much attention as other risk factors such as smoking, diet or alcohol. It is extremely important to stress that even small amounts of physical activity confer substantial benefits beyond cardiovascular and metabolic health, including improved mental wellbeing and quality of life as well as the positive effects on environment that result from replacing car use by cycling or walking. In the battle against inactivity, emphasising its harm is of paramount importance in addition to advocating the benefits of an active lifestyle. The global challenge is to make physical activity a public health priority in order to improve population health and decrease the burden of chronic disease. This aim clearly requires good quality research to provide evidence and inform public health policy, as well as ensuring that environments are safe and supportive of health and wellbeing through collaboration across all sectors of society including various stakeholders, such as health care, community planning, education authorities, nutrition, employers, transport engineers and academia.

*Rajna Golubic [2008] is doing a PhD in Epidemiology which she began in 2010. Picture credit: Sura Nualpradid and http://www.freedigitalphotos.net.

Modern misogyny and the medieval mouth

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Admittedly, discussions on medieval thought do not often start with genetics, nor such opportunistic use of alliteration. I am not the first literary historian to apply the concept of the meme to English analysis.  A meme, which is analogous to a gene, is a unit of information which is a ‘unit of culture’ – an idea, belief or behavioural pattern – that is ‘hosted’ in individuals and reproduced in new hosts over time. Evolutionary biologist Richard Dawkins coined the term in the 1970s, positing that ideas and concepts are active cultural agents, and in this way influence social and cultural practice.

Just in time for International Women’s Day on March 8, the women of the Cambridge debating team faced misogynistic attacks at the Glasgow University Union (GUU) Debating Competition. Without wishing to create a false linear narrative, I believe that looking to history can help facilitate thinking and broaden our intellectual contexts when considering patterns of thought and behaviour today.

The association of femininity with disruptive and disorderly speech found new life in the late Middle Ages; the aphorism ‘wymmen arn, are many wordys’ has been around since at least the 15th century and in post-Reformation England it was common parlance: ‘where be women, are many wordys’. The issue of problematic language was made especially exigent due to the primarily oral culture of medieval England. Literacy was reserved for men and women of status and the clergy. As such, for the wider population there was a dependence on orality that heightened the problem of the relationship between morality and speech; how language might be used subversively, and ultimately challenge authority.

The association between women’s speech and chaos became embedded in culture through theological commentary on the First Mother, or in some texts, our Grandmother. One 15th century preacher wrote:

“Eve, our oldest mother in paradise, held long talks with the adder, and told him what God had said to her and to her husband about eating the apple; and by her talking, the fiend understood her feebleness and her unstableness.” [emphasis mine]

Issues of the spiritual and physical were particularly tied up with speech and the mouth. In the Middle Ages and into the Renaissance links between the mouth and female genitalia further entrenched common associations between women’s speech and their dishonour. As Marie-Christine Pouchelle writes, these are ‘bodily orifices generally considered equivalent’. A woman speaking ‘too much’ could draw her chastity into question. In this way, there was a belief that words were actual deeds with real consequences [think philosopher of language J. L. Austin’s How To Do Things With Words, (1955)]. The definition of ‘virginity’ often included chastity in speech, with some arguments suggesting that abstaining from intercourse was not sufficient to be considered a ‘true’ virgin.

Thinking about recent local events, it is disturbing in the extreme that women have been called ‘whore’ and ‘slut’ by their male Union members when attempting to speak in debating contests. Here in the 21st century the association between a woman’s open mouth and her ‘open’ sexuality are again, however subconsciously or otherwise, being disseminated. We are reminded of Eve revealing her ‘unstableness’ through speech when one debater was told that women’s voices sound ‘hysterical’. These are men who would have found a far more sympathetic audience for their particular ideas five or six hundred years ago.

In Renaissance England, the proliferation of preacher’s manuals, sermons, tracts and pamphlets instructing correct vocal behaviour are often addressed directly to women, or have special sections devoted to women’s speech. Pamphlets, such as The Anatomy of a Woman’s Tongue (1638), and theological works like William Perkins’ The Government of the Tongue (1593), were particularly popular. Silence, the closed orifice, is most often encouraged as the best ‘ornament’ of a woman.

Recently scholars have argued that the rise of such conduct books can be seen as an anxious response to ongoing shifts in social codes. These manuals may be considered a discourse designed to boost patriarchy when it was believed to be ‘under some degree of threat’. Indeed, on a more individual scale, we may reasonably suppose that some form of threat was posed by the intelligent and world-class women speakers of the Cambridge debating team.

The history of attempts to control women’s speech and the connection of women with ‘sins of the tongue’ (with gossip, hysterical speech, the ‘nagging’ scold, and so on) are part of a history of power. Attempts to control women speaking today have a distinctly pre-modern flavour. In this particular issue, as I believe in many others, the Middle Ages offer a mirror to modern society that it has not yet dared hold up to itself. The meme is a useful way to image broadly inherited concepts. These ideas, these memes, may have changed their shape over hundreds of years, but the central negative and prejudiced associations here between women and speaking remain sadly extant.

*Kathryn (Kate) Crowcroft [2012] is twice Gates Scholar. Her PhD focusses on medical and theological ideas about the mouth from medieval into early modern culture.

How to build peace and security in Mali

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Since Mali adopted a new constitution in 1992, the country has been considered democratic and subsequent elections were lauded free and fair as President Alpha Oumar Konare served his term and retired graciously after 2002. His successor President Amadou Tuomani Toure (ATT) was on the verge of retirement after his two-year term when he was arrested by the military led by Captain Sanogo in March 2012, making Mali the main concern for the African Union’s peace and security agenda in the continent.

The junta justified the coup as necessary when the state failed to deal with the longstanding rebellion in Northern Mali. The Malian president ATT was accused of complacency. He was accused of failing to stop the Tuareg rebel group National Movement for Liberation (MNLA), which declared the independence of ‘Azawaad’, the ‘new’ self declared country of northern Mali, after seizing three of the largest northern towns Gao, Kidal and the famous Timbuktu, the ancient intellectual centre for learning in Africa. In response, the Economic Community of West Africa (ECOWAS) placed sanctions on Mali, urging the coup leaders to relinquish power, which they did by handing over power to appointed civilian leaders.

Tuareg rebellion 

The origins of the Tuareg rebellion in northern Mali can be traced to French colonisation. The French governed southern and northern Mali as one country who comprised people of different identities with little affiliation for each other as one country. Hence when the French left in 1960, the Nomadic Tuareg in the North rebelled from the South, seeking greater autonomy.

These rebellions were quashed by the military, some leaders imprisoned and the leaders retreated to the mountains in Kidal and Goa, but their grievances remained which inspired other groups in the north to rebel in 1990, 2000, 2006 and 2009. The southern post-independence governments always negotiated with the rebels by including them in government, but after the 2009 rebellion, most Toureg rebels went to Libya and joined Gaddafi’s forces and the National Transitional Council as mercenaries. After the collapse of Gaddafi’s regime, they returned with sophisticated artillery to stage a proper rebellion.

Main actors in Mali 

Similar to the Libyan conflict, the multiple actors in Mali complicate the prospects for peace and security due to the different public and private motives the different actors have. Internally, there are different rebel groups with different priorities which the Bamako government should consider for any meaningful peace prospects.

The National Movement for the Liberation of Azawaad (MNLA) is the most popular secular nationalist group, comprised of Toureg rebels who disappeared into the desert leaving the vacuum in northern Mali for the other Islamist groups which France is mainly fighting. There are five main Islamist groups which include the Ansar Dine, Al-Qaeda in the Islamic Maghred (AQIM), Signed in Blood Battalion, Movement for Unity and Jihad in West Africa ( Mujao), the Islamic  of Movement for Azawaad (IMA).

France, at the invitation of the Malian government, came to assist Mali, mainly to fight jihadists and promises to stay till July 2013 when the situation is stable. The US is also supporting the French in stopping the advancement of the jihadists who are seen as advancing terrorism in the region.

Professor Horace Campbell at Syracuse University argues that the United States of America (USA) is partly to blame for financing and training the same jihadists for the last 10 years under the Pan Sahel Initiative and the Africa Command to overthrow Gaddafi during the Libyan crisis. Media reports by Walter Pincus, a Washington DC journalist who studied the amount of money spent by the US in Mali, show more than half a billion dollars have been spent in Mali since 2002 .

The African Union and ECOWAS have performed below expectations according to the same scholar by failing to take up their responsibilities in the Libyan case and now in Mali due to capacity and political challenges which have led to them constantly being sidelined by Western interveners.  As of February 282013 ECOWAS had planned to deploy 8,000 troops in Mali to support the 1,200 French and 800 Chad troops.

Way forward

The next few months will determine the trajectory of the conflict and define prospects for peace and reconciliation in Libya. External actors should focus on supporting moderate social movements and progressive dialogues outside the main warring factions. These moderate social movements support the idea of ensuring the integration of women in the peace process , something which is lacking among other civil society movements. There is a need to ensure that reconciliation remains the core to the process by ensuring peace negotiations will be as inclusive as possible. Liberal peace processes, such as divisive elections, should be avoided in the short term as Malians work towards reconciliation.

There is a concern among critical scholars and African scholars that the French and US hunt for terrorists may overshadow legitimate reforms in favour of a political settlement and ultimate stability in Mali. There is a need to consider supporting AU- and ECOWAS-led interventions, especially logistically and technically so that Africa to take charge of the emerging crisis and ensure ownership, peace and stability in the continent.

 *Njoki Wamai [2012] is doing a PhD in Politics and International Studies. Picture credit: worradmu and http://www.freedigitalphotos.net