Surprising facts about how we talk to babies

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AddymanCasparCaspar Addyman is a Lecturer in Psychology, Goldsmiths, University of London. He previously spent 10 years working at Birkbeck Babylab. Caspar is a specialist in baby psychology with a particular interest in positive emotions in infancy. On his Baby Laughter website he has collected data and videos from parents all over the world. Here, he writes about how two psychologists and an army of babies helped Grammy winner Imogen Heap to write her new happy song for babies.  

                                       Caspar Addyman, Goldsmiths, University of London

This article was originally published on The Conversation. Read the original article.

Here’s an experiment to try next time you meet a baby, try holding a normal conversation. It is very difficult, isn’t it? Yes it is! Oh, yes it is!

When we talk to babies we all naturally switch into a high energy, sing song tone. We use simple words and short sentences. We sound excited. Our pitch rises at the end of the sentence. These particular characteristics of “parentese” or infant-directed speech (IDS) seem to be common across many languages.

A new study, published in Current Biology, has suggested there are universal changes in vocal timbre when talking to babies. Timbre describes the quality of a voice or a musical instrument. The difference between a violin and a trumpet playing the same note is a difference in timbre.

Timbre explained.

Elise Piazza, a postdoctoral researcher at the Princeton Neuroscience Institute, invited 12 English-speaking mothers to Princeton Baby Lab and recorded them talking to their babies (aged eight to 12 months) and to an adult. The recordings were converted into “vocal fingerprints” using a standard statistical method. This produces a unique frequency profile for a given speaker that can reliably discriminate one speaker from another based on timbre.

Elise and her colleagues, Marius Iordan and Casey Lew-Williams, then used a computer algorithm to compare adult and infant-directed speech. This seemed to show that all mothers consistently alter the timbre of their voice when talking to babies.

The authors ran several controls to show that this is not just a result of mothers speaking in a higher pitch to babies. But the real test came when a further 12 mothers speaking nine different languages, including Spanish, Russian and Cantonese, were also recorded. The algorithm picked up the same difference between their adult- and infant-directed speech.

Elise describes the change as a “cue mothers implicitly use to support babies’ language learning”. The next hypothesis is that infants might detect this difference to help them know when they are being addressed. The researchers are looking for ways to test this. It would be consistent with what we already know about IDS: we do it to help babies learn.

Patricia Kuhl has shown that IDS exaggerates the differences between vowel sounds, making it easier for babies to discriminate words. This pattern was found in English, Russian and Swedish. Other research found that IDS has the acoustic features of happy, adult-directed speech, and the authors said that “what is special is the widespread expression of emotion to infants in comparison with the more inhibited expression of emotion in typical adult interactions”.

Babies learning language perform some amazing feats. From the muffled confines of the womb, they have already learned enough that, at birth, they prefer their mother’s voice and her native language to another woman or another language.

Babies learn to recognise their mothers’ voices before they’re born.

A recent study found that premature babies in intensive care make more vocalisations in response to hearing adults’ speech. If adults stop responding, infants notice and also cease.

Testing five-month-old infants with this procedure also found that the infants ceased vocalising. Moreover, the more in tune these infants were to their caregiver’s behaviour at five months, the better their language comprehension was at 13 months.

In another charming study, researchers recorded proto-speech of three- to four-month-old infants talking to themselves. The babies expressed a full range of emotions in their squeals, growls and gurgles.

Clearing up a mystery

Incidentally, this new research may also clear up a mystery from my own work. Last year when we were helping Imogen Heap create a song that makes babies happy, we advised her to make sure she recorded it in the presence of her 18-month-old daughter. Research from the 1990s showed babies can tell the difference; they prefer singing that is genuinely infant directed. I never quite believed this at the time but now this new measure of timbre will let us test this out.

For babies, just as for adults, language is truly learned in conversation. From the very beginning, babies want to join in and proto-conversations start between mothers and their newborns; nursing mothers wait for pauses in their infants’ actions to talk to them. This new research highlights a universal signal that is there to let babies know that we are talking to them.

The ConversationYes we are! Oh, yes we are!

Caspar Addyman, Lecturer in Developmental Psychology, Goldsmiths, University of London

This article was originally published on The Conversation. Read the original article.


How to make babies happy

AddymanCasparCaspar Addyman is a Lecturer in Psychology, Goldsmiths, University of London. He previously spent 10 years working at Birkbeck Babylab. Caspar is a specialist in baby psychology with a particular interest in positive emotions in infancy. On his Baby Laughter website he has collected data and videos from parents all over the world. Here, he writes about how two psychologists and an army of babies helped Grammy winner Imogen Heap to write her new happy song for babies.

Being a new parent is an emotional rollercoaster. It is an even wilder ride for a baby. Baby experts often focus on coping with lows. As someone who studies infant psychology I think the highs are no less interesting. So for the last four years I’ve been researching baby laughter. Can I guarantee to make a baby laugh? Well, I’ve been working on it.

I conducted a survey of parents all over the world and have run various studies in the lab. I’ve come to see infant laughter as the flipside to all those tears. Crying and laughter are both social signals that let babies communicate with us. Crying is a signal of frustration and discomfort, laughter signals success and satisfaction. Laughs accompany each tiny triumph and each little “Eureka!”. This makes infant laughter a wonderful window into infant learning. In fact, laughter may be a tool babies use to learn about the social world.

It’s clear that a crying baby needs your help. What is less obvious is that a laughing baby is rewarding your assistance and holding your attention in order to learn from you. The biggest mystery in anyone’s life is other people. This is even more true for babies. They crave quality interactions with adults. Laughter is their secret weapon to get it. This is why laughing babies pull in hundreds of millions of views on YouTube. It also why one of the best ways to make a baby laugh is to take her seriously.

Now, if only more people would take this research seriously I might have funding to do it. Fortunately, last year I started a new job at Goldsmiths, University of London; a place with a reputation for encouraging radical ideas and creative approaches to research. (I always suspect that having blue hair may have helped me get the job.)  

Shortly after I arrived I gave a talk to my new department about my research. Straight after the talk Prof. Lauren Stewart came up to me and suggested we collaborate on something. Lauren is a professor of the psychology of music and was interested in how babies respond to music. Music is laden with emotion and so it would be fascinating to learn more about its effect on young babies. I readily agreed but couldn’t find a suitable project.

Then by weird and happy coincidence in April last year C&G baby club called Lauren up saying they wanted help to create ‘a song scientifically proven to make babies happy’. At first we were wary. Brands have a fairly poor track record when it comes to using science. However, I had previously had a very positive experience doing research funded by Pampers. I had seen that baby brands cannot afford to lose their credibility and so have to be assiduous in what they do and what they claim.  We met with C&G baby club to discuss their intentions. Our first proviso was that they shouldn’t use the word ‘prove’. Our second was that they had let us do real science. They readily agreed.

Once these ground rules were established the first step was to discover what was already known about the sounds and music that might make babies happy. We had some experience. My previous work on the Baby Laughter project had asked parents about the nursery rhymes and silly sounds that appealed to babies. Lauren’s previous research has looked at ‘earworms’, songs that get stuck in your head. We discovered surprisingly little research on babies’ musical preferences. This was encouraging as it meant this was a worthwhile project from a scientific point of view.

The next step was to find the right composer.  With the help of FELT music consultancy, Grammy winner Imogen Heap was recruited as the composer. Imogen is a highly tech-savvy musician who just happened to have an 18 month old daughter of her own. She was intrigued by the challenges of the project. Few musicians had taken on the challenge of writing real music to excite babies while still appealing to parents.  Musician Michael Janisch recorded a whole album of Jazz for Babies, but that was very slow and designed to soothe babies. Most music written specifically for babies sounds frankly deranged.

Plenty of research has looked at adults’ emotional response to music (such as the recent brain imaging study of Tinie Tempah). Research with babies is more piecemeal and eclectic, perhaps reflecting the difficulty of asking them what they like. Researchers know that babies can hear and remember music even while they are still in the womb and one curious study from 2000 found that newborn babies prefer Bach to Aerosmith. Most systematic work has been conducted by Laurel Trainor at McMaster University and her colleagues. She has found young babies have clear preferences for consonance over dissonance and can remember the tempo and timbre of music they’ve heard before. Babies prefer the female voice but like it even more when it takes on the qualities of ‘motherese’ (the high-energy sing-song tone we all naturally adopt when talking to babies.)

We met with Imogen and gave her a set of recommendations based on what we had discovered.The song ought to be in an major key with a simple and repetitive main melody with musical devices like drum rolls, key changes and rising pitch glides to provide opportunities for anticipation and surprise. Because babies’ heart rates are much faster than ours so the music ought to be more up-tempo than we would expect. And finally, it should have an energetic female vocal, ideally recorded in the presence of an actual baby.

Fortunately Imogen had her daughter, Scout, to help her with the composition. Imogen created 4 melodies for us to test in the lab, 2 fast and 2 slow ones. For each of these she created a version with and without simple sung lyrics. Twenty-six babies between 6 and 12 months came to our lab with their mums to give us their opinion on these 8 short pieces of music. Amazingly most of the mums and 20 out of 26 babies seemed to share a clear preference for one particular melody. In line with our predictions this was a faster melody.  Even more amazingly, this is was the tune that had started out as a little ditty made up by Scout.

We knew which song the mums liked because we could ask them. We also asked the mum’s to tell us what their babies prefered best, because they are the experts on their own babies. But we also filmed the babies’ responses and coded the videos for laughs, smiles and dancing. We tried measuring changes in the babies’ heart rates and using a motion capture system to see if they were moving in time with the music. Unfortunately, this hit quite a few technical difficulties and there wasn’t time to solve the problems on our very tight schedule. This was worthwhile as pilot work and will be a really interesting area for future research.

But now we had a winning melody, Imogen needed to turn it into a full length song and it needed to be funny (to a baby). The secret was to make it silly and make it social.  Around 2500 parents from the C&G baby club and Imogen’s fan club voted on silly sounds that made their babies happy. The top 10 sounds included “Boo!” (66%), raspberries (57%), sneezing (51%), animal sounds (23%) and baby laughter (28%). We also know babies respond better to plosive vocal sounds like “pa” and “ba” compared to sonorant sounds like “la”. Imogen very cleverly worked many of these elements into the song.

Next it needed to be something that parents could enjoy themselves and share with their children. Happiness is a shared emotion and the success of nursery rhymes is that they are interactive. Imogen carefully crafted the lyrics to tell a joyous tale of how we love our little babies wherever we are – from the sky to the ocean, on a bike or on a rocket. The transport theme permitted lots of plosives “Beep, beep” and bouncing actions.

Our baby music consultants came back to the lab and listened to two slightly different sketches of the full song. This time we found that slightly slower seemed to work better (163 vs 168 beats per minute). Perhaps because it gave mums and babies a little more time to respond to the lyrics. We also found that the chorus was the most effective part of the song and determined which lyrics and sound effects worked better or worse.

After one final round of tweaks from Imogen, we went for a different kind of test. We assembled about 20 of the babies in one room and played them the song all together. It was perhaps a silly thing to do but as Imogen and I sat on the sofa in front of a colourful and chaotic room full of mums and babies and pressed play we were cautiously optimistic. If you ever met an excited toddler or young baby, you will know that 2 ½ minutes is a long time to hold the attention of even one child, let alone two dozen. When The Happy Song played we were met by a sea of entranced little faces. This certainly wasn’t very scientific as tests go but it definitely convinced me that we had a hit on our hands. You can hear the song here. Please tweet me (@czzpr) and let us know if it makes your little ones happy too.

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Thanks to all the mums, dads and babies who helped with the project. We couldn’t have done it without our small army of tiny music consultants. Nor without my two assistants Omer and Kaveesha who came to us through the excellent Nuffield Brilliant Club which arranges internships for A-level student in real working science labs. It was a frantic summer but we are very happy with the final song. You see a short video about the process here:

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Now that we have a song that both novel and highly baby friendly, Lauren and I have a range of follow up studies planned. We are planning to use the song in a range of experiments looking at how mothers introduce their babies to music and hope to look properly at babies physiological responses to happy music. Meanwhile, I am finishing a popular science book called the Laughing Baby. It is all about how to make babies happy and why that is so important. You can preorder your copy here

Caspar Addyman is happy to be on Twitter @czzpr

Developmental Coordination Disorder in the Classroom











Elisabeth Hill, Laura Crane and Emma Sumner are based in the Department of Psychology’s Goldsmiths Action Lab.  Their research focuses on a range of neurodevelopmental conditions, particularly autism and developmental coordination disorder. Here, they discuss Developmental Coordination Disorder in the Classroom, which was the topic of a recent ESRC Festival of Social Science event that they organised at Goldsmiths.


What did you do in the first five minutes that you were awake this morning?  Perhaps you hit snooze on the alarm? Buried your head into the pillow? Got out of bed and walked to the bathroom? Turned on the lights? Put some clothes on and went downstairs? Whatever you did, it would have involved motor skill (in some way, shape or form) before anything else. For most of us, motor skills are rather effortless. However, for others, motor skills can be a source of constant difficulty, and can have far reaching implications on their everyday lives. In this blog post, we focus specifically on children who have a diagnosed motor difficulty termed Developmental Coordination Disorder.

(c) Serhiy Kobyakov

(c) Serhiy Kobyakov

Developmental Coordination Disorder (abbreviated to ‘DCD’, and often referred to as dyspraxia) is characterised by impairments in motor skill (including coordination problems, poor balance and clumsiness), as well as delays or difficulties in achieving or acquiring motor milestones (such as crawling, walking, and running). DCD is not merely a childhood condition – it persists throughout adolescence into adulthood – and it can have a significant effect on aspects such as quality of life, academic achievement, and self-esteem.

DCD affects between 2-6% of children, which means that at least one child in every classroom (of 30 children) will meet the criteria for a diagnosis of DCD. Recent initiatives have highlighted the need for training to improve teachers’ awareness of the difficulties faced by children with a range of conditions such as  autism spectrum disorder and developmental language disorder, with a focus on how best to support them in the classroom. However, teachers receive very little advice, guidance or input regarding children with motor difficulties such as DCD.

What needs to be done?

It is important for there to be greater awareness of the different ways in which movement difficulties can present themselves in children. For example, children with DCD may have difficulties with one or more of the following:

  • Fine motor (e.g., grasping, pinching, handwriting) or gross motor (e.g., posture, reaching) skills;
  • Locomotive (e.g., walk, run, jump, hop, skip) or non-locomotive (e.g., stretch, curl, pull, balance, swing) movement;
  • Speed (e.g., writing quickly when taking notes) or accuracy (e.g., throwing a ball towards a target);
  • Unilateral tasks (requiring one-handed, e.g., brushing teeth, using a computer mouse) or bilateral tasks (requiring two-hands, e.g., holding a bottle with one hand whilst twisting the lid with the other).

Parents and educators should be aware of all of the potential areas in which children may experience motor difficulties, and who to turn to for help.

(c) Tatyana Gladskih

(c) Tatyana Gladskih

There should also be greater awareness of the fact that difficulties may be apparent very early on in development. Looking at early motor milestones of children with DCD – including crawling, standing unassisted and walking unassisted – our research found that children with DCD were significantly delayed relative to their typically developing peers.  For example, whilst typically developing children tend to crawl at around 8 months of age, children with DCD (on average) tend to crawl for the first time at 10 months, if at all (23% of parents of children with DCD reported that their child never crawled, whereas all children in typically developing comparison group acquired this skill). Whilst there is considerable variation in the age at which all children acquire key motor milestones, parents and caregivers should be astute to possible ‘red flags’ in these areas.

This is particularly important given that poor motor skills may have knock-on effects in other areas of development. Recent research conducted within the Goldsmiths Action Lab has shown that poor motor skills may be linked to both social skills and language abilities in school-aged children. Motor skills have also been linked to broader cognitive skills such as executive functions, which refer to aspects such as planning, mental flexibility, and inhibition. Executive functions are crucial in the classroom; for example, teachers often provide a series of instructions that children have to follow, before the child must decide on an appropriate course of action, and then carry out the tasks. Unsurprisingly, many children with DCD find the classroom environment difficult; due to both motor aspects and related difficulties in broader areas of functioning. This ties in with our preliminary findings suggesting that teachers identify children with poor motor skills as being more anxious and downhearted, and highlights the negative effects poor motor skills can have.

It is important for motor difficulties to be detected and addressed early in development – by both parents and by teachers – so that appropriate support can be given to these children. Studies in adults with DCD have shown that they report significantly lower satisfaction with quality of life and also experience difficulties with aspects such as mood, general health, wellbeing and employment. If DCD is picked up early, and appropriate support given, this will have a positive effect throughout development and into adulthood, allowing those with DCD to better fulfill their true potential.

For more discussion on DCD, look up the authors of this piece on Twitter:

Laura Crane – @LauraMayCrane 

Elisabeth Hill  @ElisabethLHill

Emma Sumner @EmmaJSumner

Baby science: Making a theatrical debut

AddymanCasparDr. Caspar Addyman is a Psychology Lecturer at Goldsmiths, University of London. He is a developmental psychologist interested in learning, laughter and behaviour change. The majority of his research is with babies. He has investigated how we acquire our first concepts, the statistical processes that help us get started with learning language and where our sense of time comes from. Before moving to Goldsmiths, he spent 10 years working in Birkbeck Babylab. Here he talks about a recent collaboration with the Polka Theatre. 

Imagine for a moment that you wanted create a piece of theatre to entertain babies or a scientific experiment to test their understanding, how would you go about it? In this article I will give you a handy six step recipe that will help you get started in either situation. And along the way I hope to persuade you why these are both such worthwhile and important undertakings. The surprising thing is that the process is very similar. Despite 10 years of experience running experiments with babies I only discovered this myself very recently.

Over last few months myself and colleagues from Birkbeck Babylab  have been collaborating with the creative team at Polka Theatre. The goal has been to make a piece of theatre for 6 to 18 month old infants based on our research as part of Polka’s upcoming Brain Waves festival (21 Sept – 2 Oct 2016). Brain Waves is a two week long festival of science and theatre that matches artists and neuroscientists to create new theatre productions for children. Supported by a Wellcome Trust People Award the festival features four original works for a range of audiences between 6 months and 16 years old.

To create a show for babies, Polka turned to Sarah Argent, a very experienced theatre director, who in recent years has specialised in creating works for babies and toddlers. In February, Sarah came to Birkbeck Babylab and after speaking to a range of our colleagues she honed in me and my fellow baby scientists Sinead Rocha and Rosy Edey. Rosy studies how we read the social movements of others. Sinead investigates rhythm and dance in babies and I study what makes babies laugh. Dancing babies, social babies, laughing babies. We could see how that makes a good start for a show. Sinead and I have also spent several years studying babies’ sense of time. We were curious how Sarah and her team would work with that.

In fact, at that first meeting, we were very curious about everything…


Step zero: Why are we at the theatre?

Let’s take a step back, why would you want to create theatre for babies or try to run a psychology study with infant participants? Wouldn’t theatre for babies be limited? Wouldn’t experiments with adults give you clearer answers?

One important first principle that seems to be shared by baby psychologists and baby theatre makers is that we both treat babies as full citizens. Theatre for babies is not theatre for adults but smaller. And science for babies is not science for adults but simpler. Baby psychologists are not simply cataloguing when various abilities come online. For us, babyhood is not merely a way-station to something better. We care about what it is like to be a baby. We try to understand babies from the inside. In theatre for babies, the ambitions seem to be the same.


Step one: Why are we at the theatre, today?

Our lofty ambitions and elaborate theory won’t mean a thing to the babies.  To communicate with them we have to be concrete and we have to be focused. We must always start with a very specific question. To get answers from them we must present them with just one thing at a time.

Sarah’s previous show for babies, Scrunch, is a great example of this. It’s set at Christmas and it features just one actor (Sarah’s husband Kevin Lewis). It builds slowly and smoothly, transitioning from event to event at a pace that is often determined by the babies in the audience. Parents coming to our lab are often surprised by how short the actual experiments are. Their baby may spend as little as 3 or 4 minutes doing the task we set them. To get that exactly right, you need to deeply about your goals before you set off. You must consider lots of possible options to find the best way to ask your question.

I think this is somewhere that baby science can learn from baby theatre. In my experience people in science are impatient problem solvers. You start telling them about something and they leap ahead of you second guessing outcomes and jumping to conclusions  The tempo seems very different in theatre. Our first full day of collaboration at Polka, the whole creative team assembled with Rosy, Sinead and I to discuss our work and there was no rush. People work in theatre are a good audience. They really do listen. They absorb, then they ask great questions.


Step two: Who is our audience?

A six month old is a very different person from a sixteen month old. A hungry baby is different person from the same baby after a good meal. An overtired toddler can have a lot of angry energy. We have to work with this not against it.

We never expect any given baby to “pass or fail” and results are based on the group not the individual because we might not get a baby at their best. For similar reasons, we rarely attempt to track the development of babies over time, preferring to test a group of 6 month olds and compare them to different groups of 4 or 8 month olds.

We try to make our tasks work with a wide age range. But often babies have other ideas. Sinead and I tried to teach babies about time by playing a game. Seven times in a row, Sinead would lift the babies’ hands every 4 seconds. On the eight time, she’d sit there and see if they babies anticipated. Four, 6 & 8 month olds played the game happily. You can see a video of this here .  But from 10 months and up, babies refused to even let us hold their hands. For them a different game would be required. In baby theatre, there isn’t the luxury of having a narrow age range. The show must have broad appeal.

Babies are fantastic participants for psychological studies because they are both open-minded and honest. They will consider anything we present them with but they won’t hold back their opinions. Translating this to theatre this makes them challenge but rewarding audience.  


Step three: The story

I read somewhere that good storytelling is about being simple, truthful, emotional, real and relevant. This would make for a good infant experiment too. An ideal for infant scientists would be to observe babies solving problems in their everyday lives. We can rarely do this but our lab must recreate as much of a natural situation as possible.

And it must be engaging. Infant attention is a precious commodity. After a few minutes in one situation their attention will wander. Everything is interesting to a baby. I’ve lost count of the number of times a baby has found his or her socks more interesting than my experiment. I am very envious when I see Sarah’s shows keeping babies entranced for 20 minutes or more. If I can learn some of her tricks this collaboration will have been invaluable to me.

The final rule is “show, don’t tell.” With preverbal infants, this goes without saying.


Step four: Rehearsal

Despite all the handy rules of step three, the mantra for step four is “Easier said than done.” Nothing will work quite as you expect and solving problems is the order of the day. Early rehearsals (or piloting as we call it) are where the real creativity happens

Sarah very wisely invites some babies to those early meetings because as we know well from our babylab, no battle plan survives contact with the enemy. In one experiment we had a ball on a stick that swung round for the babies to grab. They greatly enjoyed it. The trouble was they wouldn’t let go. It took a great deal of practice to learn how to distract the babies in just the right way it that wouldn’t provoke a rebellion.

When you get to the actual performance so much is happening at once that you need to have had extensive practice. Technical and dress rehearsal are invaluable in baby science too. In our studies there is often someone hiding behind a curtain jingling bells to get babies looking in the right direction madly pressing buttons to make teddy bears pop up on screen at just the right time and to ensure all the data gets recorded.


Step five: Showtime

In a recent ‘manifesto’ on theatre for children   Purni Morrell declared that “Art has to start from a shared position of ignorance.” This holds true for science too. You can’t make up your mind in advance. Or what would be the point?

And this all goes double when you are working with babies. Babies are enigmatic. If you think you know what baby is thinking you are probably wrong. Until we are there on the day with the babies we can’t know what will happen.

I do know that I am really looking forward to the premiere of Shake, Rattle and Roll .

The Festival is supported by a Wellcome Trust People Award.

Brain Waves: Shake, Rattle and Roll, A Polka Theatre Production, runs at the Polka Theatre, Wimbledon. Times vary. Tickets: £12.50 / Concessions and previews £9.00.

Tickets are available from the Polka Theatre website and by calling 020 8543 4888.

Caspar Addyman takes further baby steps on Twitter: @czzpr.


An end to sleepless nights? New hope for families raising children with ADHD

Alice_Gregory_Oct_2015Alice M. Gregory, Professor of Psychology at Goldsmiths, University of London. She is a member of the Advisory Board for a digital parent education endeavor on infant and toddler sleep that is being supported by Johnson’s Baby. She is a Corresponding Editor (Sleep) for the Journal of Child Psychology and Psychiatry. She has previously received funding to support her work from multiple sources including the MRC, ESRC, Leverhulme Trust and the British Academy. She is a member of the Labour Party. She is currently writing a book (Nodding Off: Sleep from Cradle to Grave) to be published by Bloomsbury Sigma in Spring 2018.




Raising a child with Attention Deficit Hyperactivity Disorder (ADHD) can be difficult. Some days feel long and the respite of a peaceful night, so rejuvenating for many, may not come at all. Parents often struggle to get their child to sleep, and once they do, they can’t be sure that they won’t wake up repeatedly during the night. But there’s good news for children with ADHD and their parents. In a recent study, we found that most cases of childhood ADHD resolve over time, and when that happens, sleep quality is no worse than in the rest of the population.

ADHD is a disorder that is widely considered to start in childhood and is characterised by symptoms of inattention and hyperactivity. Although many children seem to have endless energy, ADHD is different in that it gets in the way of a child’s development and functioning.

Parents of children with ADHD sometimes feel that they have a lot to worry about, including school performance and friendships. However, one particular issue that comes up time and time again is sleep. It seems that children with ADHD are more likely than others to have sleep problems such as sleeplessness.

So, what does the future hold for children with ADHD? Do they grow up to become adults who sleep poorly, with all of the possible knock-on negative effects? This was not clear from previous literature, so we investigated this question in a study of 2,232 twin children from England and Wales. We followed them from age five to 18. Of these children, 12% had ADHD during childhood.

Good news

Our findings indicate that people with ADHD as children as compared to those without, slept significantly more poorly at the age of 18. However, 78% of the children in our sample who had ADHD as a child, no longer had the disorder when they were 18. Their ADHD had resolved over time. What’s more, the sleep quality of those participants who no longer had ADHD was no worse than those who have never had it.

We think that this provides a positive message for families struggling to cope with sleep problems in children with ADHD. This disorder may resolve over time and, if it does, it is likely that the associated poor sleep will also be a thing of the past. Yes, by 18, they may be too old to spare their parents the wakeful nights, but parents want the best for their children and it will give many some welcome solace to know that things could improve in future.

Of course, there’s an element of what comes first: ADHD or sleeplessness? The story can be complex, and it is possible that the ADHD is driving the poor sleep. However, equally, poor sleep and exhaustion in children may be expressed by restlessness, and other symptoms typical of ADHD. Also, once a sleep problem, such as sleep apnoea (where breathing may stop for alarming seconds during sleep), is resolved there can be an incredibly positive knock-on effect on behaviour and concentration during the day.

We also wanted to understand the association between ADHD and poor sleep by testing another possibility: that these associations are due to influences that run in the family. So we also investigated this. We used our twin design (comparing identical and non-identical twins) to work out the extent to which genetic and environmental factors played a role in the association between ADHD and poor sleep.

Twins showed what was nature and what was nurture.

Our analysis showed that the magnitude of genetic (55%) and environmental (45%) influences on the association were roughly the same. This suggests that to fully understand this association we need to consider both influences.

Despite spending a third of our lives asleep, historically, sleep has been somewhat neglected by scientists. We now know that sleep matters for many aspects of our mental health and well-being. Once we understand better the genetic and environmental influences – and use this information to predict who are vulnerable to these difficulties and how best to prevent and resolve them – we will be well placed to help families who are struggling to cope with ADHD, allowing restful nights to follow restful days.

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Alice M. Gregory, Professor of Psychology, Goldsmiths, University of London

This article was originally published on The Conversation. Read the original article.

Stakeholder engagement, Brexit and beyond

As the prospest of a Brexit makes waves across the UK and beyond, this is the first of two posts this week from our Department, focussing on its impact and meaning. 

Elisabeth-Hill-photo-2The first post is from Elisabeth Hill, a Professor of Neurodevelopmental Disorders in the Department of Psychology where she heads up Goldsmiths Action Lab. She is also ProWarden (or elsewhere PVC) Learning Teaching Enhancement at Goldsmiths. Her work focuses on the importance of motor development for the development of cognitive domains and daily life outcomes in those with and without a range of developmental disorders. Here, she takes us from an early foray into stakeholder engagement to Brexit and beyond.


Around 20 years ago, towards the end of my PhD at the MRC Applied Psychology Unit (APU; now the Cognition & Brain Sciences Unit), I gave a talk to a group of professional stakeholders in my field. My focus that day was the motor skills of children with specific language impairment (SLI). One or two children in every school class meet criteria for this condition, which is diagnosed entirely on the basis of language skill. However, my research highlighted that a large proportion of children with SLI struggle with motor development and experience the same difficulties as children diagnosed with developmental coordination disorder (a motor disorder that also affects 1-2 children in every school class). These days we know that motor development has a very significant impact on early and later development of a range of areas including language and social skills. It also has an impact on longer term outcomes – at school, at work and on mental health. However, that’s now. The striking memory that I want to share is that of a speech therapist (let’s call her Joanna) speaking to me after the talk. I remember her exact words:

“your work turned on a light bulb for me. My team will now assess motor skill in every child that comes to us for a detailed language assessment. We’re failing them if we don’t”.

Fast forward a couple of years and Joanna was in another audience that I spoke to where she told me that motor screening had been implemented in her team and, as a result, a great proportion of the children assessed now received occupational therapy as well as language interventions. At the time I was astounded. It turned out that my work as a PhD student was not only well received by stakeholders, but had effected a change. It was needed on the ground and it made a difference, even though it was invisible to the great majority of those who benefitted. I’d like to think that it played a small part in improving the lives of hundreds of children seen in that one service and that those children who are now adults will have had better life outcomes because of it.

Great Britain design with 3d shape of United Kingdom map colored in blue and isolated on white background.

Great Britain design with 3d shape of United Kingdom map colored in blue and isolated on white background.

I was reminded of Joanna on the morning of 24th June 2016, as I sat bleary-eyed watching the results of the EU referendum. I was reminded of her again, later in the day, as I scoured articles and images of the night before and wondered what the Brexit vote meant for the future. I was also reminded of her when thinking about the unusually unified response of universities (coordinated by Universities UK) in their campaign to Remain. And I was further reminded of Joanna when I looked at the Leave/Remain map of the UK. One of the interesting features of this map concerns the disconnect between the pro-EU views of universities and the pro-Brexit views of their local communities. With the odd exception, only universities in London, Cambridge, Oxford and Scotland seem exempt from this. This despite universities making a significant impact on their local communities: employing a significant proportion of their workforce from the local area; providing education and opportunity for the local community; and playing a significant part in advances that make a difference to these communities (in the present and the future). The reason I thought of Joanna was that the referendum results made me realise just how much we – as academics and researchers – need to do to bridge the divide between universities and their local communities. Sitting in Lewisham, a strong Remain voting community in South East London, it is easy to forget this disconnect. Yet we should not forget that we need to engage with our local community – within Lewisham, within London and within the world – and we are in a strong position to do so.

Human head on a blackboard with the word Autism on the brain

Take, for example, the work that my colleagues (Laura Crane, Lorna GoddardLucy Henry) and I have been conducting concerning the diagnosis of autism. Autism is a developmental condition affecting the way a person experiences the world around them, and it affects around 1% of the population. This means that over 700,000 people in the UK have an autism diagnosis, and hundreds of thousands more people will be affected by the condition indirectly (e.g., parents, siblings, carers, colleagues etc). Close to 1300 people participated in our research, which identified long delays in accessing a diagnosis, dissatisfaction with the diagnostic process as a whole, and a shameful lack of support post-diagnosis. As well as publishing this work in academic articles, we have tried to make this work accessible to the broader community. We have achieved this by: writing articles for lay audiences; making short accessible videos about our findings; speaking at conferences for academics and for stakeholders; setting up a project website; and engaging with stakeholders such as the National Autistic Society and Network Autism to ensure our findings are heard. Importantly, we are also preparing a short summary of the project and its findings for the participants that so generously gave up their time to take part in the research. The fact that we had collected comprehensive and high-quality data from three key stakeholder groups (adults, parents, clinicians) allowed the National Autistic Society to run a stronger and successful campaign to reduce autism diagnosis waiting times – the Autism Diagnosis Crisis campaign. A key outcome of this campaign was that it led to the NHS receiving new recommendations to consider waiting times for autism diagnosis as a key measure of how local NHS services perform.


Research can have an impact in different ways. Sometimes the research will be invisible by the time it is fully embedded (as for my PhD research, which most of the families that it benefitted will never have come across). In other cases, we – as researchers – need to find ways to engage with stakeholders, to help them see our work as relevant to them. We must also reflect on how we can ensure that we conduct research in a way that is relevant and accessible to others. One of our many challenges is how we articulate the relevance of our work to a wide array of communities in such a way that they are able to see the value of the work we do and to consider that it contributes to a brighter future. We may not have achieved this regarding Brexit, but perhaps lessons will be learned from this.

Prof. Elisabeth Hill widens the accessibility of her research on Twitter: @ElisabethLHill, and @GoldActionLab

You can also find her research on the web at: and at

One like me! Toying with the Doll Industry


Dr. Sian Jones is a Teaching Fellow at Goldsmiths, University of London. Her research focuses on discrimination and prejudice among children and adults based on membership of a given group – and how friendships may be encouraged between children from different groups. Here, she looks at the Psychology behind the importance of representing disability in the toy industry. 


A lot of attention has focused on the toy industry of late, alongside changes in what is available and who it is targeted at. This ranges from the “let toys be toys” campaign pressuring for non-gendered marketing of products, to a plethora of companies like this one  marketing toys specifically designed to eradicate ethnic bias in dolls. This is coupled with changes to Barbie dolls both to make their shape more realistic, and to represent the careers that women may pursue.

Another avenue of change has been led by the #toylikeme campaign, with a recent petition garnering over 800 000 signatures, pressuring the industry to represent disability in their product line. Watching the video below, one could accuse anyone not able to see the joy of representation of being utterly cold-hearted.


Anecdotally, I know that my mother, and many others, banned Barbies from my toy collection . This only served to make them more attractive to me, in spite of not really being a “doll-playing” child  ( I persuaded a friend to gift me one). And I can’t tell you how I would have reacted to a toy like the one above, because I never had one. But – as a scientist – I know that the plural of anecdote (be it from my own experience, or the video above) is not data – not evidence.  So are the  changes in the toy  industry worhwhile psychologically? Are they grounded in research evidence?  Or should we retire the representative toy box to the attic?

A review of the evidence suggests not. Firstly,  it turns out that what a doll looks like matters. Ditmar (2006) took 162 girls, from age 5 to age 8, and exposed them to images of either Barbie dolls, Emme dolls (U.S. size 16), or no dolls (baseline control). Girls exposed to Barbie reported lower body esteem and greater desire for a thinner body shape than girls in the other  conditions. Moreover, the careers that dolls are depicted as having does have a real influence on children’s conceptions of the career paths that are open to them (Coyle, 2010). Coyle took girls aged 4-5 years, and interviewed them, using Barbies dressed in gender traditional and non-traditional career outfits. She found that girls identified more often with the dolls in gender traditional career clothes. However, following exposure to the  dolls with gender non-traditional careers, girls saw themselves being able to engage in a greater proportion of gender non-typical careers as an adult than before exposure. This study has since been replicated (see Sherman & Zubriggen, 2014, for example) with consistent findings.

The Seminal Doll Studies 

Next, let’s look at the question of ethnicity. This is actually where the central debate started, with a study by Clark & Clark (1947) that has become a classic in Psychology.

In what became a series of experiments, Clark and Clark showed Black children between the ages of six and nine years two dolls, one white and one black, and then asked them questions, like “show me the doll that you like best or that you’d like to play with,”or “show me the doll that looks ‘bad’.” In these studies,  around 44% said the White doll looked like them. In one version of the study Clark gave the test to 300 children in different parts of the country. He found that Black children who went to segregated schools were more likely to pick the white doll as the nice one. These findings carried considerable weight. They became part of Brown v Board of Education case. And they began the start of a movement towards multiracial education. A study by Powell-Hopson and Hopson (1988) showed that in a post-intervention aimed at tackling negative stereotypes, children chose a black doll. And like the gender / career studies, this one has also been replicated, ad infinitum.  For example, in 2005, Davis asked 21 children and 71% told her that the white doll was the nice one.

Dolls are not us

In spite of the compelling findings above, the eagle-eyed among you may have started to critique them. Recent replications of the Clark doll test have used very small samples, and were not published academically. And, it has also been noted that the contact children had with different ethnicities was not controlled, and the study lacked a control for ethnicity, of both the dolls, and the experimenters. Moreover, children don’t actually play with the dolls, and this is a forced-choice task.

In the most critical appraisal, Bergner (2009) noted that these studies show very little beyond preference: they have been used to make claims about self-esteem, but self-esteem has not actually been measured. Further, since Black children do have commensurate self-esteem to white children these preference studies are just that – about preference – representing the political and capitalist culture of the time. Wanting that to change, requires much more than raising self-esteem among Black children.

In sum, there is little in the ethnicity  “doll studies” to suggest that there is a psychological need for investment in representative toys to boost children’s self-esteem. But that is because there is no evidence – not because the evidence suggests otherwise.

Back to the toy box

Before we grow disilusioned, and throw out the doll with the bath water, let’s return to disability. Here, the  toy box is less replete with resources. The market simply doesn’t prodce so many toys – although Playmobil and Lego are  due to bring out such examples this year. “Doll” study findings are consistent with the above (and the above caveats). For example, Saha et al. (2014)  showed children with Down Syndrome two dolls, one with a “typically developing” appearance and one with the phenotypic features of Downs Syndrome. Fifty four children participated in play sessions with both dolls and were then interviewed. They prefered to play with, and attributed more positive traits to, the typical doll than the doll with Downs Syndrome.

That’s all very well, but, as noted earlier, it takes two to tango. And going back to the market, isn’t it important that toys represent diversity to all  children? In a study by Srinivasan and  Cruzhis (2015) children between 6 and 13 years of age used ethnically diverse dolls to explore and verbalise their knowledge of ‘race’. Children were able to articulate how they related to these dolls. Dolls, it seems, may be an important educational tool, for opening up dialogue. Further studies with such dolls (e.g., Smith, 2013) indicate that such dolls support the development of young children in increasing their empathy and in opening discussion about treatment of stigmatized groups. A project evaluating their use is underway.

Where now?

It seems from this review that – as far as gender is concerned – there is  strong evidence for the psychological impact of (poor) representation on children’s Psychology. There is less evidence of impact from ethnic doll studies – but this is largely because the studies have measured only ethnic preference, and not looked at outcomes like career aspirations or race-related self-esteem. Studies that have, have noted an impact. The research agenda might turn to closing this gap: to measuring the self-image, aspirations, empathy and anxiety (as well as prejudices) of those  from all groups exposed to representative toys. As it stands, in a world of White privilege, it is arguably hardly surprising that a white doll is preferred.

When it comes to disability, unlike with ethnicity, one finds that such research has not been an option until very recently: the toys themselves are, relatively speaking, all-but absent.  We know that children most easily discuss issues in contexts that are familiar to them – such as play (Srinivasan &  Cruzhis, 2015). In this regard, there is growing evidence that representative dolls are a good thing. They open dialogue around prejudice and enable discussion and empathy. If such toys are not there, the opportunity for this discussion is lost. At a broader level, if we do want to change the status quo in our society – we know that acceptance of prejudice and inequality doesn’t magically appear at 18 years of age. When it comes to fairer representation, there might be no better place to start than the toy box.


Schools without sanctions


Alice Jones is a Senior Lecturer, and Director of the Unit of School and Family Studies. Her work focuses on understanding how students with behavioural difficulties can achieve their potential in school, as well as developing methods of promoting social and academic inclusion.

Here, she provides an update on an on-going project that explores one school’s aim to learn without sanctions.


Spring was a busy term for the Unit of School and Family Studies. Two of our current PhD students (Hannah Smith and Dawn Rose) were offered exciting postdoctoral positions, and another (Guilherme Wendt) will represent Goldsmiths at the World Congress of Psychology in Japan in July after being awarded an ‘Emerging Psychologist’ award. Dawn Rose, one of our PhD students, also received a commendation from the Warden in Goldsmiths first Public Engagement Awards for her role in The Happiness Project, a collaboration between theatre, scientists and school students put on at the Edinburgh Festival and the Camden Roundhouse last year.

We’re currently working with schools across the UK, on a range of projects exploring mental health, bullying and behaviour; but we’re particularly interested in working with schools to develop research projects that are timely and contribute to the development of evidence-based practice.


Translational research in action

We can’t carry out the sort of work that we do without working closely with teachers, educational psychologists and other professionals working in schools. Our previous work (Frederickson, Jones, Warren, Deakes & Allen, 2013; authored by academic researchers, educational psychologists and teachers) sets out how we can combine teacher feedback with the most appropriate available research to help provide solutions to school problems. Working in such a way means that we are able to translate the available research into practice quickly, while also carrying out work that we can feed back into that evidence-base.

This project examined the existing research about the differing profiles of social and emotional abilities of children with severe behavioural difficulties, and used it to think about why existing practice wasn’t as effective as it could be, and how we might improve things. For example, some school-based initiatives for behavourial difficulties focus on empathy, but if a child has difficulties empathizing with others (Jones, Happe, Gilbert, Burnett & Viding, 2010), then that strategy might be rather limited in its effectiveness. Similarly, it is important to understand that not all children are motivated by the same outcome – not all students seek social approval and friendship (Warren, Jones & Frederickson, 2014). One group of young people that we are particularly interested in are commonly described as having ‘limited prosocial emotions’ (DSM-V), or ‘callous-unemotional traits’ (Frick, Ray, Thornton & Kahn, 2014). In our 2013 study, we developed and examined a new method of working with students based on our profiling of their abilities and difficulties. After a year, we were able to demonstrate behavioural improvement alongside reductions in fixed-term exclusions from the school and a positive acceptance of the programme by school staff.


Can schools work without sanctions? What we’re doing now

Our current work is interested in how far school sanctions really influence behaviour, and whether schools can exist without them. Working with schools for children with social, emotional and mental health difficulties allowed us insight into how effective traditional methods of classroom behaviour management are for children who find being in school tougher than most. We partnered up with outstanding Kilgarth School in Birkenhead, a secondary school catering for the needs of students with social, emotional and mental health difficulties (a range of difficulties previously labeled as social, emotional and behavioural difficulties). Our collaboration was covered by The Telegraph last year, and you can read about it here. Kilgarth are a brilliant model of reaching out to use research, but also giving back through research and training opportunities for educational and other agencies, including the police and prison service.

Screen Shot 2016-05-20 at 16.41.06

For some children punishment, or more commonly, the threat of punishment is ineffective. Young children who are considered to have a fearless temperament are typically resistant to punishment (Fanti, Panayiotou, Lazarou, Michael & Georgiou, 2016). Similarly, children who have behavioural problems and difficulties with empathy are similarly uninfluenced by sanctions – time out has little effect on their behaviour, and these children don’t seem to be made as sorry or upset by strategies like time-out (Hawes & Dadds, 2005; Miller et al., 2014). More recently, teachers have also reported an association between callous-unemotional traits and insensitivity to punishment (Allen, Morris & Chhoa, 2016). In contrast, it may be the case that certain types of rewards are a useful motivating factor in developing desired behaviour.

We worked with Kilgarth School to develop a whole-school system that was built on the available research relevant to their students, and that met the needs of the students, teachers, governors and everyone else involved with the school. The result is a school system that works to positively exploit and develop strengths. Students report that they feel a greater sense of responsibility, and are motivated by the potential for their behaviour to be rewarded. (This has been an exciting opportunity of seeing earlier research being put into action and is also generating interest in collaboration with partners beyond education) Our evaluation of the evidence-based school system is on-going, but preliminary feedback seems to be positive (not only for the students but also teachers). We’ll let you know once our final results are published…


This work couldn’t happen without excellent student researchers involved in the project; thanks particularly to Bethan Carter (MSc FCP, 2015) and Elizabeth Booker (BSc PCN, 2016) for your involvement.

Alice tweets without sanction @dralicejones

Time in Mind: How your brain tells the time


AddymanCasparDr. Caspar Addyman  is a Lecturer in the Department. He is a developmental psychologist interested in learning, laughter and behaviour change. The majority of his research is with babies. He has investigated how we acquire our first concepts, the statistical processes that help us get started with learning language and where our sense of time comes from.

Here, he looks at the last of these: how our brain tells the time.

It is a defining feature of the modern world that we all seem to be short of time, all the time.  We are poor at managing our time. We are poor at estimating time. And until recently psychologists have been poor at explaining why. I believe my research on how the brain represents short intervals might give us a few clues. The short answer that we’re bad because our brains don’t contain clocks. Instead we must guesstimate the passage of time based on how our memories fade.

This might not sound too radical to you but it goes against received wisdom. For 50 years the main explanation of how you judge intervals has been based a little stopwatch in your head. This is known as the pacemaker-accumulator model, as it involves something that ticks (the pacemaker) and something that counts the ticks (the accumulator). This is a fairly intuitive idea but I would argue it is completely wrong.

It’s wrong for three main reasons. The biggest problem is that if we had an internal clock we would be a lot better at judging time than we are. Secondly, the clock model can’t explain how we judge the time in retrospect. Thirdly, it can’t easily explain why time flies when you’re having fun.

My memory based model of interval time solves all these problems. Developed with colleagues at Birkbeck and Burgundy and called the Gaussian Activation Model of Interval Timing (GAMIT, French, Addyman, Mareschal & Thomas, 2014) it is much simpler than the name suggests. The key idea is that you estimate time passing by how your memories fade. The more time has passed the fuzzier they are. The more things that happen to you the faster they will fade and the faster you will feel time is passing.


You have no clock

Humans and rats are terrible at telling the time. Get us to press a lever when 10 seconds have passed we will generally do so somewhere between 8 and 12 seconds. Correct on average but with quite a bit of variation and humans are no better than rats. If the interval is increased to 20 seconds our estimates are just as bad with estimates spread out between 16 to 24 seconds. If the interval is twice as long you (and your pet rat) are twice as bad.


This is where the real problem lies. If you had some sort of clock in your head then random unreliability in your clock would average out the longer you ran it. Your errors should be proportionally smaller on longer intervals. Pacemaker-accumulator models normally get round this by saying that as numbers get larger, counting gets harder. This is a kludge. In our model the errors are impossible to get around, as memories fade uncertainty increases, bad estimates are as good as it gets.    


Timing, all the time.

Mental clocks have a second problem. What to time? Because it seems like we judge the time of any event we remember or can locate in the sequence of our experiences  How long ago did you start reading this article, this paragraph? When did the waiter leave our table? When did that blue square appear on the screen in this experiment I am in? If mental timing is done with a clock then either you need to start a separate timer for every single event or master clock labels everything. The former would be highly wasteful while the latter would complex and couldn’t easily account for errors we mentioned above.

With a memory model all this comes for free. When we access our memory of a past event, there is more uncertainty the longer ago it was. The instant the waiter leaves the memory of that event is clear with each passing moment details become less clear. What was he wearing? Was I leaning forward or backward? What did you just say? Our brains are used to dealing with uncertainty, in our view, timing is just another example.


TIme flies when you are having fun

Imagine you are about to give a five minute interview on live television. You are off camera waiting your turn and there is nothing for you to do but focus on the passing time. Five minutes feels like forever. Then it is your turn and suddenly everything is happening at once. You get to the end in no time and are surprised it is over so soon. But then looking back on it, the pattern is reversed. You remember little about the waiting but the interview is full of event. If you didn’t know otherwise you would swear the interview was longer than the wait.

This difference between these so called prospective and retrospective timing judgements has been confirmed in a large meta-analysis of 117 studies (Block, Hancock & Zakay, 2010). It is so striking that most researchers say it means there must be two independent timing systems. This seemed ridiculous to us and our model was largely developed to unify these two effects.

In our view, judging the passing of time is a combination of two things; how much is happening and how much attention we are paying to the passage of time. Our model quantifies how these two factors interact to create distortions of time. The more that happens the faster your memories fade making recent events feel further in the past.  Yet with more happening the less attention you can give to the passing of time and it feels like things are happening faster.


Time will tell

We are still developing our model and it’s not only the game in town. In a recent review of the field we found over 20 different approaches to how we judge short intervals (Addyman, French & Thomas, 2016). And then there are whole other classes of models that look at very fast timing under a second or on the order of days. In the realm of our daily experience from seconds to minutes we believe that our model is the most elegant and intuitive. But the real test is how well it fits the data. And that’s what we are working on now.

Dr. Caspar Addyman  tweets in real-time at @brainstraining




One rather nice thing about this research project was that I experienced a genuine “Eureka moment”, a flash of insight where I unexpectedly solved a big problem.

Derived from the story of ancient Greek scientist Archimedes leaping from his bath, shouting Heurika (I have it) when he realised how to measure the volume of an irregular shaped body by immersing it in water. No-one knows if that story is true. But it has become a common stereotype of the scientific process that it proceeds through giant leaps of insight or discovery. Mostly, it doesn’t. Science, like life, is mostly hard work with the occasional bit of good luck. Ninety-nine percent perspiration and 1 percent inspiration as Thomas Edison was fond of saying.

My lucky moment came one morning on the Victoria line somewhat north of Pimlico. For several months I had been struggling with how build effect of attention into our original computer model of fading memory. I had no clear ideas but was supposed to have a meeting that lunchtime explaining my progress. Sleepy and forlorn I just stared out of the window. Whereupon the answer just popped into my head; adding a loop to our network would let it look at its own previous estimates. When more events were competing for attention those loops would happen less frequently.

I knew straight away it would work and went happily to my meeting. By the end of the day, I had computer model that did as I expected within a week the paper was written (Addyman & Mareschal, 2014) Needless to say, in a few hundred tube journeys since then, it hasn’t happened again. Maybe Edison was exaggerating.


This article is published with a Creative Commons Attribution NoDerivatives licence [], so you can republish  it for free providing you link to this original copy.