“Boy Brain, Girl Brain” – A TRIGGER Seminar on Cognitive Early Development

This post was contributed by Lucy Tallentire, from the School of Business, Economics and Informatics

boygirlSex differences have been the source of contentious debate in recent years, beguiling scientists, lay people and major stakeholders like the NHS and pharmaceutical companies. There are obvious physiological and anatomical differences between the sexes but cognitive differences are often conveyed through stereotypes – that males have better motor and spatial abilities and females have superior memory and social cognition skills, for example. While there is research to support some areas of cognitive sex difference, recent studies have shown that the magnitude of sex differences has decreased in recent years. This suggests the causes of these differences may have less to do with one’s genetics than one’s environment – that nurture may be just as powerful as nature to one’s brain development. It also provides further evidence for the effectiveness of contemporary social movements to bridge the gap between “women’s roles” as nurturing child-bearers and “men’s roles” as workers.

So what can research into typical and atypical early development tell us about sex differences? And should we be focusing on biology as the route of sex differences?  These were just some of the questions addressed by guest speaker Teodora Gliga, from Birkbeck’s Centre for Brain and Cognitive Development, at a special seminar on Wednesday 7 December. The event was arranged and hosted by the Birkbeck TRIGGER initiative, a European-wide research project dedicated to Transforming Institutions by Gendering Contents and Gaining Equality in Research.

Why look at sex differences?

Hormonal differences initiated by biology and genes affect physical and cognitive development; the genes on sex chromosomes and the levels of sex hormones influence the brain during early development. Many psychiatric disorders are more common either in boys or girls; boys are more likely to develop autism – the focus of Teea’s research – but girls are more prone to anxiety. By utilising animal models of development and human studies that have revealed early biological differences between sexes present even before birth, Teodora was able to explain differences in susceptibility to risk factors associated with autism.

However, that the effect is amplified when the brain is exposed to risk factors or adversity, such as stress, demonstrates that biology is not the only variable in the development of a disorder like autism; recent research by Anne Fausto-Sterling on how best to study difference in infant early development has shown that, although birth characteristics provide a moment to begin analysis of developmental processes that lead to sex-related differences in behaviour and preference, this is an arbitrary starting point. Many of the biologically-oriented studies use prenatal sex differences in hormone production as the explanation for later difference in behaviour but according to Fausto-Sterling, it seems likely that hormones are but one of many factors affecting human foetal growth and development. In this framework, behaviour after birth develops independently as small biological differences are slowly magnified by external influences – social, cultural and environmental.

Case Study: The British Autism Study of Infant Siblings

The British Autism Study of Infant Siblings was established to explore the development of autism in young infants, and to advance and improve early detection and diagnosis. Parents frequently tell medical professionals that they knew there was something different about their child’s development quite early on, often long before an official diagnosis is received. However, it has been hard for researchers and clinicians to know about the very early signs for autism as they typically only see the child when they are over three years old, when a diagnosis can be reliably given. Although diagnoses for autism spectrum disorder (ASD) have fallen in recent years, it remains more commonly developed by boys – 1:42 boys and 1:189 girls, according to studies from 2010 and 2014.

Scientific understanding of the neurobiological basis of autism has advanced dramatically in past decades, but there is still very little known about how the condition develops over the first few years. This is precisely why Teea’s team at the Birkbeck Babylab launched the Studying Autism and ADHD Risks (STAARS) project, which looks specifically at the early development of baby brothers and sisters of children with autism spectrum disorders, attention deficit disorders and typical development. The project is notably an output of the TRIGGER programme, as the initiative provided the funding for the research assistant who carried out the analysis.

Of the participants with elder siblings with an ASD diagnosis, 20% went on to develop and get a diagnosis for ASD. The study showed a negative correlation between IQ and severity of symptoms, which provides further evidence that IQ is a protective factor against the development of autism. But Teodora was quick to remind the audience that there is still a lot of debate on these findings – there has not been one specific gene that can explain more than 10% of cases. One must also consider that the symptoms of autism might be exposed more easily in this case study, as it must be conducted on “High Risk” families, where they might be more actively looking for symptoms because of a heightened awareness of autism, and where interactions with siblings with an ASD diagnosis might even be a contributory environmental factor.

Teea finished her presentation with a call for more statistics and better models through which to analyse these statistics. If we are to gain a deeper understanding of ASD, its causes and its early detection, we must focus first on mediating effects that may reveal protective mechanisms, and on increasing our understanding of underlying biology of sex differences and the implications of hormones. According to the expert, “it is a story of interactions between biological, social and cultural factors with cascading effects.”

Further Links:

The TRIGGER team at Birkbeck is currently seeking mentees and mentors for their Athena SWAN mentoring programme 2016/17. The mentoring scheme is open to research, technical and academic staff who work at Birkbeck – find out more here.

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Science Week: The latest findings in autism research

This post was contributed by Guy Collender, of Birkbeck’s Department of External Relations.

ProfessorMichaelThomas400, of Birkbeck's Department of Psychological Sciences

Professor Michael Thomas shared the latest autism research during Science Week. Photo: Harish Patel

The media spotlight never seems to be far away from autism, and interest in the developmental disorder has been reignited by the measles outbreak in Swansea. The discredited research linking the MMR vaccine and autism is in the news again, and other debates about autism abound – what causes it?, how early can it be diagnosed?, and how can it be treated?

In light of these controversies and unanswered questions, it was not surprising that a packed lecture theatre awaited the thoughts of Professor Michael Thomas when he delivered his talk about autism on 17 April during Birkbeck’s Science Week. Grabbing the last seat on the back row, I joined the audience and found it refreshing to hear a considered and comprehensive assessment of the spectrum disorder that affects how a person communicates with, and relates to, other people. The talk helped separate fact from fiction and explored an interesting new hypothesis about the cause of autism too.

Professor Thomas, of Birkbeck’s Department of Psychological Sciences, explored the different causal explanations of autism. He described how genes play the major role, but that most cases involve a mixture of common variants (not mutations) and that genetic explanations do not tell the whole story. For example, Professor Thomas said that an identical twin has a 60-90 per cent chance of developing autism if the other twin is affected by the disorder. Therefore, environmental factors must play a role in determining whether a child develops autism as if genes were wholly responsible the figure would be 100 per cent. He also highlighted how the severe deprivation experienced by children in Romanian orphanages caused around 10 per cent of these children to show quasi-autism.

Birkbeck research
Referring to recent Birkbeck research, Professor Thomas explained that changes in brain activity among babies can be detected and are able to predict whether a child will develop autism. Ongoing work at Birkbeck as part of the British Autism Study of Infant Siblings (BASIS) Network is investigating these early months, and early behavioural indicators of autism are being identified at 12 months.

Professor Thomas mentioned screening for autism, but indicated that this isn’t yet a realistic prospect because of the costs involved, concerns about the accuracy of the diagnosis, and what happens after diagnosis. For instance, if autism can be diagnosed, but effective interventions do not exist, then how helpful is a test? Earlier in the lecture, he referred to interventions and stressed that where they are effective they need to be sustained and intense. Research has shown that the most promising approach is early intensive behavioural intervention, which needs to start before age two and be carried out for at least 40 hours per week over two years.

New hypothesis
Professor Thomas also set out a new hypothesis regarding the cause of autism. He explained how connections within the brain are ‘pruned’ in early and middle childhood as unused connections, which are expensive for the body to maintain, are cut away. The pruning hypothesis proposes that this natural process malfunctions in children with autism. Instead of just cutting unnecessary connections, exaggerated pruning means functional connections within the brain are cut. In some children this occurs slightly later, allowing normally looking early behaviour followed by the loss of acquired skills during the second year of life. In other children, exaggerated pruning in the first year leads to atypical development after the first few months of life. The hypothesis predicts that such pruning should affect the sensory and motor systems first, and home videos of infants with autism recorded at four or six months do show some anomalous movements.

The complexities of autism were clearly made throughout the presentation, but what was also clear is that more and more research is leading to a greater understanding of autism and is likely to lead to earlier and earlier diagnosis of the disorder.

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BabyLab Showcase 2012

This post was contributed by Denise Breitenbach and Yvonne Whelan 

Introduced by Prof. Mark Johnson, this year’s Birkbeck BabyLab Showcase highlighted the importance of researching aspects of infant cognition over time. Between birth and adolescence, our grey ‘jelly-like’ brains expand three times in size and undergo an astounding amount of structural adaptation. These changes aren’t solely reliant on our genes: genetic information unfolds over time by interacting with our external world experiences. For example, social skills related to the processing of facial cues such as smiling, develop early on as children experience seeing others’ faces. Early life contextual factors can also impact negatively upon development: poverty has been linked to effects on the brain which can result in a range of mental health difficulties.

So how are BabyLab scientists linking structural brain changes to the development of perceptual, cognitive, motor and language abilities? As babies often lurch rapidly between contented gurgling, gutsy wailing and gentle snoozing, novel experimental techniques are required. These include: 1) Behavioural testing such as eye tracking (e.g. used for testing preferential looking at faces versus complex objects) 2) Electromagnetic recording methods (EEG/ERPs) using a damp hat to record tiny voltage changes on the scalp as groups of neurons synchronously fire together on exposure to a task 3) Optical imaging (NIRS), where weak light beams are used to track blood flow in the brain as babies are thinking/perceiving stimuli 4) MRI scanning – used for sleeping babies to discover more about brain structure and functioning.

Changing their mind

In the first showcase talk, Dr Natasha Kirkham explained how good working memory (WM) and inhibitory control (IC) in children contribute to the development of decision-making, remembering of rules and the production of contextually appropriate behaviour  (e.g. speaking loudly in assembly, but not at the cinema). Childhood development of WM and IC has been tested using the Dimensional Change Card Sort Task where firstly, children were asked to match a target card with reference stimuli according to shape, and then to only match according to colour. Although 3 year olds performed worse than 5 year olds where there was a category conflict according to the prior rule (e.g. a red truck had to be matched with a red star), scaffolding a 3 year old child’s learning experience helped to improve their performance. For instance, instructing them to repeat a new rule, rather than solely providing ‘yes/no’ feedback to card choices delivered the greatest improvement. Next, Natasha provided us with an additional experimental example testing WM and IC – the ‘Delay of Gratification Task’ where in order to earn many more Oreo cookies, children were asked to refrain from eating those already placed before them until an adult re-entered the room. Amusing strategies employed included children sitting on their hands or putting cookies in drawers!

Shining Light on the Infant Brain

In the second showcase talk Dr Sarah Lloyd-Fox informed us how an exciting and novel way to shine light on the functioning of an infant’s brain is to do it literally by using a technique called NIRS. This works by shining a weak light into the infant’s head which passes through the infant’s skull and reaches underlying brain tissue.

NIRS comes with many benefits to researchers: it can be used on babies who are awake (so they can be tested with visual imagery rather than sounds only) and has better spatial resolution than MRI. At Birkbeck, NIRS has been used to investigate when infants start to see and interpret actions, alongside questions such as ‘is our ability to use our hands to interact with our environment related to how we respond when we see other people performing similar actions?’. As emphasized by Dr. Natasha Kirkham earlier, the experimental value of play should never have been underestimated and this question was examined using games testing infants’ manual expertise. Intriguingly enough, evidence suggests that there may be a relationship between the way our developing brain responds to the sight of human motion and the motion we learn to form ourselves.

Infant time perception – ‘Escaping the Eternal Now’

In the third talk Dr Caspar Addyman highlighted how babies are often absorbed in something in the ‘now’: “in one moment babies can be in howls of tears and the next, in peals of laughter”.

How is it that humans gauge how quickly an event ‘feels’? Caspar described how for adults the longer ago something occurred, the fuzzier a memory exists of it. Judging the ‘fuzziness’ gives us a measure of how long ago in time it occurred. Since infants’ memories are not very well developed, it is difficult for them to judge the continuity of events. Thus, in order to learn more about the development of infants’ perception of time, BabyLab researchers are testing the long and short term memories of 6, 10 and 14 month olds using habituation (the classic technique of making babies bored!) with heart rate measures and eye movements being monitored. In addition, movement is thought to be very important to an infant’s developing understanding and judgement of time and events – at 6 months the world has to come to you, by 14 months exploration increases as crawling and walking ensue, expanding an infant’s sphere of the world. Such interaction may link to changes in the judgement of time. This is ongoing research and we look forward to hearing the results of Caspar’s study in the future.

Autism in infancy

The final talk, given by Dr Teodora Gliga, described the progress developmental science is making towards understanding autism spectrum disorders (ASD). ASD are presently diagnosed from 24 months onwards when children fail to meet social communicative developmental milestones. Researchers at Birkbeck are investigating how ASD can be detected and diagnosed earlier, for example by trying to decipher the pre-requisites for language development. As ASD is a genetic disorder (there is a 10% chance of developing ASD if one has a sibling with it vs a 1% chance for the general population), a prospective longitudinal study has been used to investigate infants who have siblings with autism over a 3 year clinical assessment period. 

Evidence indicates that although there are no differences in paying attention to faces between ASD and typically developing infants at 6 months and 12 months, there are early differences with gaze direction and a failure to follow gaze from 6 months – a precursor of social ability. In order to inform intervention strategies, future studies will need to focus on testing children at multiple time points and using measures such as attention (looking away from irrelevant objects), the ability to discriminate gaze direction, follow gaze, to acquire words,  maternal input (words child hears), the social and biological environment, a child’s genes, and risk factors during pregnancy.

Read more about BabyLab research in the news.

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