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ABC Studentships
Investigating the relationships between orthographic, phonological and semantic processing in
children's reading development and dysfunction: from neuropsychology to neuroimaging.
Supervisory team: Joel B. Talcott, Kim Rochelle
Becoming an expert reader requires the development of competencies in phonological, orthographic
and semantic analysis skills. Our recent work with children in mainstream primary schools has
suggested that the lack of age-appropriate ability in either orthographic or phonological skills can be
a risk factor for impaired reading development. However, impairments in reading component skills
may be linked to different developmental trajectories. Children with deficits in orthographic skills,
but age-appropriate phonological skills may simply be delayed in their acquisition of sight word
vocabulary and may eventually 'catch-up' with their peers in reading skills if they are provided with
appropriate tuition. In contrast, selectively impaired phonological skills experienced by some
children might be characterised by an atypical developmental trajectory in language skills that may
not be remediated with either maturation or normal exposure to age-appropriate instructional
materials.
This project will investigate further these putative relationships between orthographic, phonological
and semantic processes, focusing on assessment of children's literacy development both in normal
classrooms and in children referred to the Aston Development and Assessment Clinic for assessment
of specific learning disabilities. The student will work with our research team toward the following
project aims: 1) to better understand the developmental trajectories of orthographic, phonological
and semantic skills in children's reading development and dysfunction through the examination of
archival longitudinal data; 2) to develop and refine additional tests of these skills for use in
assessment of paediatric samples in different age groups; 3) to better understand the neural
implementation of orthographic, phonological and semantic processing skills, focusing on their
interaction during children's reading development through the use of paediatric MEG.
Neural and behavioural correlates of Developmental coordination disorder.
Principal Investigators: Kim Rochelle & Ngoc Jade Thai
Developmental coordination disorder (DCD) is a prevalent motor coordination disorder affecting
approximately 5% to 6% of school-age children with evidence that it may persistent into adolescent
and adulthood. The aetiology of developmental coordination disorder is unclear, current knowledge
is that the disorder often coexists with attention-deficit hyperactivity disorder (ADHD),
speech/language impairment, and/or reading disability. A need exists for a much clearer focus on
DCD in child psychiatry and in child neurology research. The co morbidity of DCD with ADHD is highly
suggestive of cerebellar dysfunction. However the heterogeneity of this disorder means the
cerebellum is unlikely to be the only neural correlate. Combined neuroimaging and behavioural
studies of learning-related change in motor behaviour will therefore be crucial in furthering our
understanding of DCD in addition to disentangling its co morbidity with ADHD. The aim of the project
will be to explore with behavioural testing and structural neuroimaging techniques to validate
clinical subtypes of DCD and ADHD in a clinical population against aged match and younger controls.
Induced Gamma and Beta Oscillations: a window onto Visual Development.
Principal Investigators: Dr Ian Holliday and Prof. Gina Rippon
There is extensive evidence of developmental trajectories in the visual system, continuing perhaps
even as late as the mid-teenage years, with some potential for plasticity being retained in adulthood.
Much groundwork needs to be done to establish the developmental trajectories of cortical
oscillations in normal children and young adults, and this will be the focus of the proposed
studentship. The studentship proposal utilises Magnetoencephalographic (MEG) techniques to
establish normative ranges for gamma and beta responses in visual paradigms in three cohorts of
children 5-8, 9-12, 13-16 as a basis for future studies of paediatric cohorts from groups, such as
children with autism spectrum disorders.
We have well-established MEG protocols for examining visual gamma and beta sources that can be
adapted to paediatric use that would enable us to advance this research boundary rapidly. The
studentship would involve psychophysical assessment or visual task performance alongside the MEG
investigation, permitting a detailed correspondence to be made between behavioural and
neurophysiological measures .
The studentship work would directly feed into MEG studies in patient groups in which visual
processing is disturbed in development, such as Autistic Spectrum Disorder and dyslexia.
Development of MEG based metrics to investigate language development in normally developing
and developmental disorders.
Principle Investigators: Ngoc Jade Thai, Cristina Romani, Stefano Seri.
Non-invasive neuroimaging techniques have become key research tools for evaluating brain function
and developmental trajectories in children. Language acquisition is a crucial part of cognitive
development. Language deficit can often be one of the earliest indicators of neurological
impairment and the first sign of a developmental delay.
Previous neuroimaging studies have found that the neural substrates supporting language in
typically developing children change in structure and function across development. We propose to
investigate the neural foundations of core neuropsychological functions supporting language
maturation in typically developing children with particular focus on phonology, prosody, and word
segmentation.
The main focus will be to address to what degree is typical left hemisphere lateralization of language
due to pre-existing functional asymmetries rather than development of language skills. This will
involve developing a battery paediatric compatible language tasks designed to investigate the
sentential and lexical language skills in early and later in childhood, which can be applicable to
neuroimaging studies using MEG.
We also propose to evaluate connectivity patterns between activated regions using linear methods.
The acquisition of normative data across the developmental period will allow disentangling
developmental patterns in brain activation from changes due to developmental or acquired
abnormalities and form the bases for the use of MEG based measures for clinical purposes.
Explorations of motor and balance skills in children with developmental disorders.
Principal investigator: Kim Rochelle
Background: Developmental Dyslexia, Developmental Coordination Disorder (DCD), and Attentiondeficit Hyperactivity (ADHD) disorder are among the most commonly diagnosed disabilities of
development in the UK, representing a significant problem for education and social health [1]. The
core phenotypes of these disorders are underspecified. Compounding this difficulty is the high
overlap between these conditions [2,3,4]. This co-occurrence might be explained in two
complementary ways: 1) true overlap between developmental disorders with different aetiologies;
2) by mechanisms shared in common at a neurophysiological level. Difficulties in postural stability
have been suggested as an prospective indicator of dyslexia risk [5, 6] but similar deficits are also
prevalent within the ADHD and DCD populations [3,4,7].
Aims and objectives: The main aim of this project is to develop sensitive and valid measures of
balance for predicting, identifying and potentially discriminating between different developmental
disorders. Balance and posture assessment already forms part of the statutory national curriculum
framework, but methods usually used in schools lack adequate sensitivity and objectivity. Design:
Quasi-experimental, independent groups (disability versus control groups). Unselected samples of
adults and children from the dyslexia and normal reading populations. Background publications are
provided in [8,9].
1] American Psychiatric Association (2000). Diagnostic and statistical manual of mental disorders
(4th edn., text revision). Washington, DC: Author.
[2] Willcutt, E. G., Pennington, B. F., Olson, R. K., Chhabildas, N., & Hulslander, J. (2005).
Neuropsychological analyses of comorbidity of reading disability and attention-deficit/hyperactivity
disorder: In search of the common deficit. Developmental Neuropsychology, 27, 35-78.
[3] Kaplan, B. J., Dewey, D., Crawford, S. G., & Wilson, B. N. (2001). The term comorbidity may be of
questionable value in reference to developmental disorders: Data and theory. Journal of Learning
Disabilities, 34, 555-565.
[4] Piek, J. P., Pitcher, T. M., & Hay, D.A. (1999). Motor coordination and kinaesthesis in boys with
attention-deficit hyperactivity disorder. Developmental Medicine and Child Neurology, 41, 159-165.
[5] Fawcett, A. J., Nicolson, R. I., & Dean, P. (1996). Impaired performance of children with dyslexia
on a range of cerebellar tasks. Annals of Dyslexia, 46, 259-283.
[6] Moe-Nilssen, R., Helbostad, J. L., Talcott, J. B., & Toennessen, F. E. (2003). Balance and gait in
children with dyslexia. Experimental Brain Research, 150, 237-244.
[7] Diamond, A. (2000). Close interrelation of motor development and cognitive development and of
the cerebellum and prefrontal cortex. Child Development, 71, 44-56.
[8] Rochelle, K.S.H., Witton, C. & Talcott, J.B. (2008). Symptoms of hyperactivity and inattention can
mediate deficits of postural stability in developmental dyslexia. Experimental Brain Research, 192,
627-633.
[9] Rochelle, K.S.H. & Talcott, J. (2006). Impaired balance in developmental dyslexia: a meta-analysis
of the contending evidence. Journal of Child Psychology and Psychiatry, 77, 1159-1166
Neural and behavioural correlates of Developmental coordination disorder.
Principal Investigators: Kim Rochelle & Ngoc Jade Thai
Developmental coordination disorder (DCD) is a prevalent motor coordination disorder affecting
approximately 5% to 6% of school-age children with evidence that it may persistent into adolescent
and adulthood. The aetiology of developmental coordination disorder is unclear, current knowledge
is that the disorder often coexists with attention-deficit hyperactivity disorder (ADHD),
speech/language impairment, and/or reading disability. A need exists for a much clearer focus on
DCD in child psychiatry and in child neurology research. The co morbidity of DCD with ADHD is highly
suggestive of cerebellar dysfunction. However the heterogeneity of this disorder means the
cerebellum is unlikely to be the only neural correlate. Combined neuroimaging and behavioural
studies of learning-related change in motor behaviour will therefore be crucial in furthering our
understanding of DCD in addition to disentangling its co morbidity with ADHD. The aim of the project
will be to explore with behavioural testing and structural neuroimaging techniques to validate
clinical subtypes of DCD and ADHD in a clinical population against aged match and younger controls.
Investigating dynamic changes in neuronal network function in epilepsy.
Principal Investigators: Stephen D. Hall, Stefano Seri, Ngoc Jade Thai and Gavin L. Woodhall
A seizure can be described as abnormally synchronized activity in a large population of
brain cells, which causes a disruption in brain function. It is apparent that the disorder is
progressive, and seizures themselves have effects on the structure and function of the
brain that predispose it towards further seizures. The understanding of individual
neuronal and network behaviour in epilepsy has greatly improved over the last two
decades. However, we are still particularly reliant upon animal models, and mechanistic
data at the synaptic and neuronal levels (e.g. rat model) are difficult to reconcile with
studies at the human network level (e.g. EEG/MEG).
Here, we will adopt an integrative approach to study the electrophysiological
mechanisms of seizure initiation and epileptogenesis. We will compare post-surgical in
vitro electrode recordings of resected brain tissue with pre- and postoperative in vivo
MEG ‘virtual electrode’ and ECoG recordings in paediatric patients undergoing surgery for
refractory epilepsy. This will provide the first characterisation of in vitro and in vivo
electrophysiological activity in human brain tissue, which can be used to explore disease
mechanisms.
In order to elucidate the mechanisms by which seizure initiation and epileptogenesis
occur, it is essential that the electrophysiological data recorded at the in vitro and in vivo
levels can be adequately compared. This project will focus on the development and
implementation of analytical tools that can effectively characterise electrophysiological
phenomena in epileptic tissue observed using multiple modalities.
Small World, Big Picture: can graph analysis help explain visual feature binding in Autism?
Background: If, as has been claimed, Autistic Spectrum Disorders (ASD) are characterised by
anomalous temporal binding[1], then they should show abnormal functional connectivity during
tasks requiring visual feature binding(VFB). VFB, when viewing illusory figures such as Mooney faces,
has been shown to be associated with changes in both local gamma activity[2] and functional
connectivity[3] but as both can be seen in the absence of VFB, neither can be considered to be
neural correlates of the process. Perhaps then, the critical feature is not the presence or absence of
functional connectivity but the pattern, or topology, of the connections that exist[4]. However,
although some evidence supports this position[5], the approach has been severely restrained by
computational limitations. Fortunately, developments from graph theory (e.g. Small World
Networks[6]) that can be interpreted as measures of local and global efficiency[7] can overcome
many of these limitations and some have already been applied to EEG/MEG[8]. Despite successes in
revealing differences between healthy and clinical populations (e.g. Alzheimer’s, Parkinson’s,
Schizophrenia and closed head injury), however, this approach has not been applied to ASD and has
been studied in the resting state almost exclusively. The aim of this project is to indentify
appropriate experimental protocols and analysis techniques that can be used to characterise
anomalies in the topology of connectivity seen in ASD.
Hypothesis: Perception of images requiring VFB will be associated with a more ‘small world’ pattern
of connectivity than comparable images not requiring VFB in controls. Individuals with ASD will show
a topology of connectivity with local efficiency comparable to controls but with relatively impaired
global efficiency.
Method: EEG/MEG will be collected from ASD participants and matched controls during rest and
appropriate experimental conditions that involve visual feature binding. Functional connectivity will
be measured using two methods that eliminate volume conduction (Phase Locking Index[9] and
Imaginary Coherence[10]) and graph theory measures of ‘Small Worldness’ (Global and Local
efficiency) will be calculated from the resulting matrices and compared between conditions using
Partial Least Squares Analysis[11]
Expected Outcomes: This will be a significant test of an important theoretical perspective on the
dynamic organisation of the brain in ASD and will also permit a comparison of two important
measures of functional connectivity.
References:
1.
Brock, J., et al., The temporal binding deficit hypothesis of autism. Dev Psychopathol, 2002.
14(2): p. 209-24.
2.
Tallon-Baudry, C., et al., Stimulus specificity of phase-locked and non-phase-locked 40 Hz
visual responses in human. J Neurosci, 1996. 16(13): p. 4240-9.
3.
Rodriguez, E., et al., Perception's shadow: long-distance synchronization of human brain
activity. Nature, 1999. 397(6718): p. 430-3.
4.
Tononi, G. and G.M. Edelman, Consciousness and complexity. Science, 1998. 282(5395): p.
1846-51.
5.
Burgess, A.P., J. Rehman, and J.D. Williams, Changes in neural complexity during the
perception of 3D images using random dot stereograms. Int J Psychophysiol, 2003. 48(1): p. 35-42.
6.
Watts, D.J. and S.H. Strogatz, Collective dynamics of 'small-world' networks. Nature, 1998.
393(6684): p. 440-2.
7.
Latora, V. and M. Marchiori, Efficient behavior of small-world networks. Phys Rev Lett, 2001.
87(19): p. 198701.
8.
Reijneveld, J.C., et al., The application of graph theoretical analysis to complex networks in
the brain. Clin Neurophysiol, 2007. 118(11): p. 2317-31.
9.
Stam, C.J., G. Nolte, and A. Daffertshofer, Phase lag index: assessment of functional
connectivity from multi channel EEG and MEG with diminished bias from common sources. Hum
Brain Mapp, 2007. 28(11): p. 1178-93.
10.
Nolte, G., et al., Identifying true brain interaction from EEG data using the imaginary part of
coherency. Clin Neurophysiol, 2004. 115(10): p. 2292-307.
11.
Lobaugh, N.J., R. West, and A.R. McIntosh, Spatiotemporal analysis of experimental
differences in event-related potential data with partial least squares. Psychophysiology, 2001. 38(3):
p. 517-30.
Neural correlates of configural and part-based object processing in adolescence
Principal Investigators: Dr Luc Boutsen and Dr Martin Jüttner
The ability to visually recognize objects requires substantial time to develop. Such maturation
effects have been predominantly investigated in and most clearly demonstrated for face
perception. Considerably less certain is the developmental trajectory for the recognition of
non-face objects. We have recently demonstrated a developmental dissociation between the
trajectories of part-based and configural object recognition (e.g., Jüttner et al., 2009). In
these experiments, children aged 6-16 years were asked to judge the correct appearance of
familiar animals and artifacts that had been manipulated either in terms of individual parts or
their part relations. We found that for part changes (part-based judgments) recognition
performance even in the youngest children (aged 7-8 years) matched that of adults closely.
By contrast, recognition of altered part relations (configural judgments) showed a distinctly
protracted development and reached adult levels of performance only at an age of 11-12
years.
The aim of this project is to investigate, through a series of EEG studies, the neural
basis of this dissociation in perceptual object processing using event-related potentials
(ERPs) and frequency analyses. In particular, we want to use this technique to assess the
development of the modulation of visual ERPs (N170 and P100) and evoked gamma-band
power by part-based and configuration-based perceptual processing. Both visual ERP
components (Boutsen et al., 2006) and gamma-band activity (e.g., Werkle-Bergner et al.,
2009) have been implicated in visual processing and may develop over time. By comparing
these neural correlates between the age groups that represent the critical time window during
which visual configural processing develops, i.e., 8-10 and 12-14 years, this project
contributes to the study of the neural locus of developmental processes in object recognition.
References
Boutsen, L., Humphreys, G. W., Praamstra, P., & Warbrick, T. (2006). Comparing configural
processing in faces and objects: an event-related potentials study. NeuroImage 32, 352367.
Jüttner, M., Petters, D., Wakui, E. & Davidoff J. (2009). The development of part-based and
configural object recognition in adolescence. Perception 38, Supplement 165.
Werkle-Bergner, M., Shing, Y. L., Müller, V., Li, S., Lindenberger, U. (2009). EEG gammaband
synchronization in visual coding from childhood to old age: Evidence from evoked
power and inter-trial phase locking. Clinical Neurophysiology 120, 1291-1302.