RESEARCH

Memory

Our aim is to understand memory impairment resulting from brain injuries occurring during infancy. We have several ongoing projects investigating the impact of hypoxic (lack of oxygen) / ischaemic (impaired blood flow to the brain) events early in life on the development of memory. Hypoxic-ischaemic events can result in hippocampal damage which is, in turn, correlated with memory impairment.  The degree of impairment depends on the degree of damage sustained by the hippocampus. In cases where the damage is both bilateral and extensive, individuals develop a syndrome known as Developmental Amnesia (DA). Patients with DA are markedly impaired in episodic memory.

Using neuropsychological and MRI techniques, we are investigating the neurological causes and the long-term outcome of hippocampal damage in individuals with both mild-moderate memory impairment as well as those diagnosed with the syndrome DA. It is hoped that this will aid the development of rehabilitation methods.

In addition, working with DA patients enables us to investigate the neural structures involved in different types of memory, e.g., the contribution of the hippocampus to visual and auditory long-term memory.

Current Projects:

– Consequences of neonatal exposure to hypoxia/ischaemia on the hippocampus and the basal ganglia in infants with cardiorespiratory disease:  A longitudinal study of memory and sensorimotor outcome from birth to 3 years.

– Long term memory and language outcome in relation to the memory and language networks after childhood cardiac arrest.

– Non-verbal auditory long-term recognition memory in developmental amnesia

– Tracking the hippocampal and diencephalic circuit of cognitive memory in developmental amnesia with diffusion tensor imaging

– White matter damage revealed by DTI in patients with acute cardio-respiratory disease and bilateral hippocampal pathology

– Hippocampal pre-frontal interactions assessed on Self-Ordered-Pointing-Task with increasing memory load in patients with selective hippocampal pathology of early onset

– Episodic memory and motor skill learning associated with selective brain damage in children with low blood sugar (hypoglycaemia)

Speech and Language

We study the brain basis of childhood-onset speech and language disorders.

Nearly 5% of children have a communication disorder of unknown origin. Speech and language problems can also occur in certain neurological conditions resulting in dysphasia, dyspraxia of speech, or dysarthria. Using neuropsychological evaluations and structural and functional imaging, we aim to understand brain plasticity and functional reorganisation after early injury, and identify the neural networks serving speech and language disrupted in acquired and developmental conditions, such as: genetic disorders; epilepsy; tumours; traumatic brain injury; stroke; preterm birth; developmental coordination disorder.

Current Projects:

– Reading networks in the developing brain

– Developmental Coordination Disorder: a Brain Imaging study

– Elucidating the neural pathways and genetic basis of speech

– Effects of a mutation in FOXP2 on motor and language tracts in the human brain

– FOXP2 mutation and auditory processing in the KE family

– Working memory deficits in association with a mutation of the FOXP2 gene

– Plasticity of language networks after epilepsy surgery: implications for outcome

– Functional imaging to guide neurosurgical treatment:  a systematic pre- to post-operative evaluation in children

Motor Organisation

Young people with white matter damage to the sensorimotor pathways display atypical motor development that results in reduced opportunity for exploration and environmental interaction, which in turn, impacts their cognitive and social development. We seek to combine motion capture (kinematics) and dynamical systems analysis to develop a quantitative assessment of these anomalous trajectories and provide the basis for (a) an early and accurate diagnosis, (b) the design of novel interventions, when the brain is at its most adaptable, and (c) a method to detect and validate any changes resulting from interventions.

We seek to formally describe motor synergies on the basis of both kinematic and physiological information. For the older children, our aim is to design and trial novel interventions, such as virtual reality games, that can increase the repertoire of movements in the upper limbs, thus potentially improving their motor outcomes.

Current Projects:

– Improving the outcome of hemispherectomy in children with intractable epilepsy

– Tissue preconditioning to prevent ischaemic damage: movement coordination in infants

Early Detection

Cognitive and social difficulties are common long-term outcomes in a variety of paediatric medical conditions, even in the absence of major neurological problems or global developmental delay.  These problems can require expensive long-term educational support and intervention throughout the school years and have a serious long-term impact on the child and their family.  Even so, they are typically not identified until some years after discharge from hospital, and often come to light when children experience difficulties at school-age.

Potentially, early identification of the infants who are particularly likely to develop difficulties would allow intervention before problems become entrenched and lead to a history of school and social failure.  However, the typical instruments used to examine outcomes in infants and pre-schoolers often focus on global developmental quotients and may not be optimal for identifying the early stages of difficulties in specific cognitive or social skills.

Projects in this area focus on developing behaviour and brain-based (e.g., EEG) measures of specific cognitive and social skills in infants and preschoolers for better identification of those at risk, and include study of infants born preterm, with infant-onset epilepsy, congenital visual impairment and sickle cell disease.