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Mature older man sitting on sofa, looking at computer screen, having video call

By Josie Clarkson

With much of the UK just emerging from its second coronavirus ‘lockdown’ into new tiers, the amount of social contact we are able to have is still limited. Among the worst affected are people living in the country’s care homes, 70% of whom have dementia. A recent report in The Lancet identified 12 risk factors for dementia and named social contact as an important defence against a decline in cognitive function as we get older.

Engaging in frequent social contact helps to increase and maintain ‘cognitive reserve’ – a measure of a person’s resilience to decline in thinking skills.

The Lancet report states that engaging in frequent social contact helps to increase and maintain ‘cognitive reserve’ – a measure of a person’s resilience to decline in thinking skills. This is because socialising stimulates the brain by challenging it to process lots of information simultaneously.

Conversely, research has shown that social isolation results in an increased rate of deterioration of symptoms among people with dementia. According to the Office for National Statistics, during the first lockdown in April there was an 80% increase in deaths due to dementia, even aside from COVID-19. It is therefore more vital than ever to keep in touch with people with dementia. Doing so will help to alleviate isolation and may slow the progression of the dementia itself.

The introduction of social distancing has restricted much of our social contact to virtual platforms – especially for people with dementia, many of whom fall into a vulnerable category.

The introduction of social distancing has restricted much of our social contact to virtual platforms – especially for people with dementia, many of whom fall into a vulnerable category. This transition online has benefits and drawbacks, and opinion is mixed as to whether digital forms of communication are an adequate substitute for face-to-face contact. On one hand, many people with dementia may struggle to access and use this technology, or to detect the usual non-verbal cues many rely on in communicating with others. On the other hand, virtual platforms open up a huge range of support services that may not be available locally – including, for example, resources in other languages.

With an estimated 850,000 people living with dementia in the UK – and at least 50 million worldwide – efforts to find new treatments and preventive strategies have never been more urgent. There is currently no ‘cure’ for dementia – an often-misunderstood term that describes a group of symptoms associated with and caused by conditions such as Alzheimer’s disease, Parkinson’s or vascular disease (to name just a few). The field is well known for its failed drug trials.

One organisation working to make much-needed breakthroughs in dementia is Dementias Platform UK (DPUK). Based in Oxford University’s Department of Psychiatry, DPUK was set up to accelerate progress in dementia research.

When we eventually deal with COVID-19, dementia will still be here in its many forms – and we’ve seen during this pandemic how deeply people with dementia and those who care for them have been affected.

Professor John Gallacher is Director of DPUK and Professor of Cognitive Health at Oxford. He says: ‘Dementia is certainly one of the biggest public health challenges facing us globally in the 21st century. When we eventually deal with COVID-19, dementia will still be here in its many forms – and we’ve seen during this pandemic how deeply people with dementia and those who care for them have been affected.

‘But I’m optimistic about the future of dementia research. I believe that within the next five to ten years we will have disease-modifying treatments that will improve people’s lives. I’m more cautious about using the term “cure” – but treatments to delay the onset or slow the progression of dementia, yes.’

DPUK’s work focuses on better understanding the complexities of dementia in humans. There are three main strands to this work:

  • a Data Portal giving researchers access to huge amounts of population health information – critical in helping identify the earliest signs and determinants of disease;
  • a package of experimental medicine studies aiming to shed light on the root causes of dementia, such as what triggers inflammation in the brain;
  • a ‘trials delivery framework’ that will help match public volunteers to the right dementia trials and studies, ensuring we can quickly understand what works (and what doesn’t).

 I believe that within the next five to ten years we will have disease-modifying treatments that will improve people’s lives.

Professor Gallacher says: ‘One of DPUK’s most important contributions to dementia research is the vast quantity of data it makes available to researchers so we can explore the varied causes of dementia and get a much more complete picture of why some people degenerate faster than others.

‘History shows us that individual specialties working independently will not bring the solution. We have lots of weapons in the fight against dementia: genetic information, brain imaging, stem cell technology, survey data and more. By bringing it all together and working collaboratively we will maximise our chances of success.’

DPUK has recently been awarded £7.5 million in renewed funding from the UK’s Medical Research Council.

A man with synapses connecting around his head

By Jacqueline Pumphrey

Researchers led by a team at the Wellcome Centre for Integrative Neuroimaging at the University of Oxford have developed a new framework that binds together the way the brain forms maps of space to the way the brain understands relationships of any kind – general mental maps. The new framework, published in Cell, resolves a decades-old debate on how the same part of the brain, the hippocampus, seems to be important for two seemingly very different functions – how to move around in space and how to remember relational structures like a family tree. The researchers say that they are just two sides of the same coin.

For example, when you watch a romantic comedy, there is always a common structure: 1) character setup, 2) they meet, 3) romance starts, 4) obstacle #1, 5) uncertain journey, 6) obstacle #2, 7) all goes wrong, 8) happy resolution. This structure is the same, irrespective of the exact storyline and characters.

In a similar way, whenever you go into a new house, you know that the house is likely to be set up according to some standard rules: it has rooms that connect with each other, the bedrooms are likely upstairs and the kitchen likely downstairs.

Both houses (relationships in space) and understanding films (relationships in episodes) can be understood in the same way – working out a relational web. This relational web is very useful: knowing a web for houses means you can walk into any house and have a good guess where you might find a bathroom; and knowing a web for romantic comedies means you can turn on the TV and if they’re kissing in the rain it means the film is about to end.

Using this framework of learning relational webs, the researchers built the ‘Tolman-Eichenbaum Machine’ (TEM). This is a deep neural network model named after Edward Tolman and Howard Eichenbaum, two researchers whose ideas influenced this work. Without ever telling it the underlying web, TEM was able to learn the web and use it to its advantage. For example, by seeing several different families, it could learn what a family was i.e. the family tree relation web. When learning about space, the TEM’s neurons behaved exactly numerous neurons that have been recorded in animals over the last few decades (in two areas of the brain associated with memory – the hippocampus and entorhinal cortex) including grid and place cells that allow us to keep track of our position in space.

TEM also makes novel predictions about how neurons behave. Previously it had been thought that place cells are randomly allocated for each new situation. This work, however, says that although the allocations may look random, there is in fact a hidden preserved structure – the relational web of space. This is exactly what they subsequently found when analysing recordings of grid and place cells.

Diagram of strings connecting different figures on a map

TEM in visual. Image by Gil Costa

Lead researcher, Dr James Whittington, said: ‘There has been lots of confusion over how the hippocampus can do so many apparently unrelated things. This work shows that those apparently unrelated things are actually the same things but seen from different angles. Thinking in this way opened up the possibility to build a mechanistic model to really understand how this part of the brain works.’

Leslie Scott with jenga tower

This month Senior Associate of Oxford’s Pembroke College, Leslie Scott, was honoured by her wildly popular invention Jenga being inducted in the US’s National Toy Hall of Fame. Sold in 117 countries across the world and loved by all ages, as a family- and pub-favourite, Jenga is now officially a classic.

Science Blog caught up with Leslie Scott, to find out how the game evolved and why its simple concept keeps people coming back for more.

How did Jenga come into being?

As a game, it evolved amongst my family when we were living in Ghana in the mid-70s. I moved to Oxford a few years later and had a set of these blocks and started to play it as a game. They weren't exactly like the Jenga blocks are now but the principle of the game was there.

I played a lot with friends here in Oxford. But it took a long time for the penny to drop that this didn't exist already as a game. People and children have obviously been piling up blocks of wood for years, but actually to turn that into a game, it just didn't exist.

Original Jenga packaging

So in 1982, I decided I was going to take this game to market.  But that's when the issues started. I knew nothing about the toy industry and nothing about retail business. But I was just so convinced this was going to work.

What are the secrets to Jenga’s success?

Not many people realise this but each one of the blocks in the game are slightly randomly different from each other. And that's absolutely deliberate. Because without that, the game just really doesn't work. If they're all identical it just sits there. So that sort of randomness was a factor of the original, handmade wooden blocks.

I had to figure out how to mass market some of these flaws. Then there was the question of how many actual blocks there should be, plus their size. The original ones were slightly longer than Jenga blocks are now. That meant you couldn't assemble them three by three and make a stable tower to start with - there were gaps between each.

But I figured out that if you made them just slightly shorter you can square it up. So you can start with a fairly stable tower. The decision to go for 54 blocks was trial and error. You start with 18 rows and it just worked - I don't think there was anything more scientific.

How did you scale up production to maintain randomness?

I spoke to a carpenter I knew and asked him how would you do this. He came up with a very clever suggestion, which was to send the planks of wood through a sanding template that was not in itself 100% even. So these planks of wood would go through that template, and then be chopped up into the pieces.

Leslie Scott with jenga tower

The next stage was introduced by a group of people in Yorkshire at a place called Camphill. It's a sheltered community for adults with learning disabilities and other special needs - it's a movement all around the world. In Yorkshire they have a farm, they've got a dairy, but they also have a woodworking shop.

They had already been making wooden toys, and a person that I knew at Oxfam suggested talking to them. I went up and saw them and asked if they would be interested in doing this for me? And they said, “Yes”, provided that if it became successful, I took it elsewhere to be manufactured because they didn't want to spend the rest of their lives just churning out hundreds and thousands of the wooden blocks!

They came up with this idea of tumble polishing them. When you very lightly tumble polish it puts a nice sheen on them. It smooths the edges, but it doesn't smooth them totally - it introduces another level of slight inconsistency, so it's really clever.

I haven't seen how Hasbro make them now in vast quantities, but I understand it's not that different. This randomness is still built into it. People love playing with wood. There's that tactile element to it, but it's also actually key to the functioning of the game.

What do you think is Jenga’s enduring appeal?

I think it appeals because you can play it with anybody - as long as you've got a certain amount of dexterity. It still seems to require skills, but they're not skills that take a lifetime to learn. And plus, it is never the same. There's nothing inevitable about who's going to win. When you start the game you could make exactly the same moves, but it's not going to end up in the same way because of the randomness.

It's thrilling when you're teetering at 30 layers already. And it's terrifying it when it comes back to you.

Also, I didn't deliberately intend it to be a cooperative game. But if you watch people playing, once the tower gets beyond a certain height, most people end up wanting it to get higher. They really want it to get high, so it becomes almost like a team effort, in a funny way. The excitement comes in trying to get it as high as possible. Nobody deliberately wants it to fall over. So on one hand it could be considered a very competitive game, on the other hand, there’s actually quite surprisingly cooperative play involved. It's thrilling when you're teetering at 30 layers already. And it's terrifying when it comes back to you.

Where did the name Jenga come from?

I grew up speaking Swahili and the word jenga is the imperative form of kujenga, the Swahili verb “to build.” When I first put it on the market, I called it ‘Jenga the perpetual challenge’. And the company that took it on - first of all Irwin in Canada, and then subsequently Hasbro worldwide - hated the word ‘perpetual’. They said Jenga doesn't mean anything and nobody in North America will understand what perpetual means either! So I had a bit of a battle with them and I ended up saying, “Okay, okay, okay, you don't have to call it perpetual.” Even though I actually really meant it – I’d thought about that hard. It is always a challenge. It's not the ultimate challenge, but it's always a challenge. But I have this feeling that by giving up on 'perpetual' I got away with keeping Jenga [laughs].

Do you feel that your childhood influenced the development of Jenga?

I think we should leave children to think and do things for themselves a great deal more than we do now.

When we were kids, the idea that every moment of the day was somehow timetabled wasn’t there. Even at school, there were large, large chunks of time where we literally went out and played, and we were not being supervised for every moment. And, personally, I think we've got the concept of education a wee bit wrong. I mean, I think we should leave children to think and do things for themselves a great deal more than we do now.

If you think about some of the toys that are now produced for children, there's an awful lot that have stories already built into them. I think it's interesting that the National Toy Hall of Fame (which has inducted 74 items), have quite a large number that don't have an inventor as such. There's things like the cardboard box, the stick, marbles. What they're trying to recognise are playthings that have actually contributed to genuine play, playful play.

I think the opportunity to be creative, or the environments in which you can become creative arise when somebody else hasn't told you how to think about something. I don't know how Jenga fits into that, but play is a subject that really interests me.

What is a play – what is a game?

We use terms like “Somebody's got to play the game” or we imply that incredibly serious things are games - like business is a game and life is a game. I think we need to be quite careful how we define what we mean by ‘play’ and make sure that if we are saying, “it's all a game” that at least we actually know what those rules are when we're playing this game. And we know when we're outside of that too.

The thing about a game is that you've agreed to take part in it, it is something voluntary. Secondly, you've got a set of rules that you've agreed that you understand, you're playing by that set of rules, you're playing within a confined space, a delineated area, you're playing for a certain amount of time. So there's a beginning and there's an end to it too. 

How do you feel about Jenga entering the National Toy Hall of Fame?

I am thrilled! And I’m honoured and delighted, too, that I am to be included in an upcoming Strong Museum exhibition of women who created  a toy or game that became a classic. It’s very exciting.

The National Toy Hall of Fame at The Strong Musuem, was established in 1998 and recognizes toys that have inspired creative play and enjoyed popularity over a sustained period. Each year, the prestigious hall inducts new honorees and showcases both new and historic versions of classic toys beloved by generations. Final selections are made on the advice of historians, educators, and other individuals who exemplify learning, creativity, and discovery through their lives and careers. Toys are celebrated year-round in an exhibit at The Strong museum in Rochester, New York.

For more information about the hall, visit toyhalloffame.org.

Tiger with example simulations

By David Macdonald, Director of WildCRU

Tigers are in dire straits, with prospects for the Indochinese subspecies among the most dire of all. This is why I want to spotlight the work of Eric Ash for leading research on one of the few known breeding sites for the subspecies anywhere in the world. 

Eric Ash, a doctoral student at Wildlife Conservation Research Unit (WildCRU), part of the University of Oxford’s Department of Zoology, has dedicated himself to the conservation of tigers in Thailand for the last nine years. Now, with our collaborators at the Freeland Foundation, he has led our new paper published in the journal, Land.

The under-studied and endangered Indochinese tiger faces extinction and continuing declines, a distinction that unhappily makes the subspecies a candidate for Critically Endangered status

The under-studied and endangered Indochinese tiger (Panthera tigris corbetti) faces extinction and continuing declines, a distinction that unhappily makes the subspecies a candidate for Critically Endangered status. Thailand plays a crucial role in its conservation – there are few known breeding populations in other range countries. Our work has focused on Thailand’s Dong Phayayen-Khao Yai forest complex (DPKY), a group of five protected areas and UNESCO World Heritage Site, where Eric and Freeland Foundation, in partnership with the Thai-government and Panthera, conducted a massive camera-trapping study to find out just how the tigers there were faring.

A graphical abstract of the paper's methods

Importantly, we evaluate the sensitivity of population connectivity models to the variation and interaction of key factors, such as landscape resistance to movement, dispersal ability, population density, and mortality, over a series of timesteps. The article, led by researchers at WildCRU, offers insight into potential tiger range expansion scenarios.

The authors utilize spatially and temporally-dynamic simulations to model tiger population changes and dispersal from this landscape to potential habitat elsewhere in Thailand, Cambodia, and Laos, areas where tigers are thought to be extinct.Our new paper builds upon the remarkable news that this vital population of tigers could be recovering, as evidenced by signs that tigers are beginning to disperse from core areas into frontier habitat from which they had previously been extirpated

Our new paper builds upon the remarkable news that this vital population of tigers could be recovering, as evidenced by signs that tigers are beginning to disperse from core areas into frontier habitat from which they had previously been extirpated.

This was a huge analytical effort, informed by an even greater effort under arduous conditions in the field which generated over a million camera-trapping images and almost 80,000 collective trap nights over nine years. The team ran advanced analyses, requiring months of high-level computing, which produced 24,300 simulations of population, landscape connectivity, and density of dispersing individuals across the landscape to evaluate the effect of key factors.

The result? The computer models suggest that the tiger’s fate is extremely sensitive to variations in mortality and dispersal ability – and, over time, these two factors interact to strongly affect predictions. For the technical aficionado: incorporation of an explicit mortality component, reflecting differences in probability of survival across the landscape, combined with increased dispersal ability, resulted in considerably lower estimates of population and connectivity.

These results are hugely important for tigers, but they also offer an important lesson more broadly: given the importance of population connectivity modelling in cutting-edge ecological research, the approach of the WildCRU team can inform future assessments for rare or threatened species where empirical data are scarce – a challenge faced by many researchers around the world.

This study is among the first explicitly to evaluate the interaction of dispersal ability and mortality on population size, distribution and connectivity in a spatially and temporally explicit dynamic framework. The authors are convinced that future studies should adopt this approach, explicitly accounting for mortality risk across landscapes and potential interactions with dispersal ability over time. The ways in which these factors can vary over time in reality can drastically affect the simulated results. Importantly, for translating this research into impact, the study identified potential population growth and range expansion scenarios for tigers along with key factors relevant to their long-term management across this key landscape in Southeast Asia.

'How Important Are Resistance, Dispersal Ability, Population Density and Mortality in Temporally Dynamic Simulations of Population Connectivity? A Case Study of Tigers in Southeast Asia', Ash, E.; Cushman, S.A.; Macdonald, D.W.; Redford, T.; Kaszta, Ż. Land 2020, 9, 415. https://www.mdpi.com/2073-445X/9/11/415

Hybrid metal halide perovskites with atomic-scale resolution

For the first time, researchers from Oxford’s Departments of Physics and Materials have managed to image hybrid metal halide perovskites with atomic-scale resolution providing new insights into these wonder-materials. A paper published in Science shares the groups’ findings about the materials’ remarkable self-healing powers; the findings further our critical understanding of how such perovskites work and are an essential step closer to the commercial production of perovskite solar cells.

Perovskites hold the promise of a new dawn for photovoltaic and optoelectronic applications – solar cells and light-emitting devices

Professor Laura Herz from Oxford’s Department of Physics and corresponding author, says: ‘Perovskites hold the promise of a new dawn for photovoltaic and optoelectronic applications – solar cells and light-emitting devices – but there is still much we need to know about them. We need to fundamentally understand these materials in order to fully harness their power. Up until now, researchers essentially had to guess how processing affected the material and so, in turn, the solar cell performance; our work will allow the field to directly determine how different fabrication routes affect the structure.’

Remarkably rapid recovery

The materials are very soft and therefore electron-beam sensitive however, using specialist electron microscopy imaging, the team were able to observe the perovskite structure at atomic resolution. They found that prolonged electron irradiation degraded the structure as expected but that an intermediate structure formed that allowed for the material’s rapid recovery. Further observations of the atomic arrangement within the hybrid perovskite films showed that small inclusions of lead iodide (which is used as an ingredient) form a surprisingly coherent transition boundary that nearly perfectly follows the surrounding perovskite structure and orientation. The observation suggests that lead iodide may seed perovskite growth and explains why an excess of lead iodide tends not to impede solar cell performance. Studying the material at this atomic level revealed essential information about the nature of the structure’s boundaries, defects and decomposition pathways.

Dr Mathias Rothmann, from Oxford’s Department of Physics and lead author, comments: ‘We have been able to study photoactive perovskite thin films with atomic resolution in their native thin-film state, which is what you find in a solar cell device. We were able to observe a range of different boundaries between the crystal domains in the film, which are very important for solar cell performance but not very well understood.

'We observed different types of defects that haven't been described for this material before, as well as the inclusion of a secondary material – all of which can potentially have a significant impact on the overall performance of the solar cells, but which are impossible to study without the level of resolution we have managed to get. This detailed level of understanding has been essential for the rise of silicon-based solar cells, and we can therefore only begin to imagine the impact it will have on the future of perovskite solar cells.’

Perovskites for commercial solar cells

Professor Herz concludes: ‘Our findings have revealed several, possibly unique, mechanisms that underpin the remarkable performance of this technologically important class of hybrid lead halide perovskites. The highly adaptive nature of the perovskite structure accounts for its exceptional regenerative properties and our atomic-resolution observations of interfaces within the material will contribute significantly to being able to eliminate defects and optimise interfaces. This is exactly the exciting kind of information we need to make perovskites ready for commercial solar cells.’

Read ‘Atomic-scale microstructure of metal halide perovskite’, in Science, Vol 370 Iss 6516.