A5006117314- Dementia and Cognitive Impairment Research
- Stroke Rehabilitation and Recovery
- Spatial Neglect and Hemispheric Dysfunction
- Neurological Disease Mechanisms and Treatments
- Functional Brain Connectivity Studies
- Spatial Cognition and Navigation
- Advanced Neuroimaging Techniques and Applications
- Urban Green Space and Health
- Older Adults Driving Studies
- Alzheimer's disease research and treatments
- Advanced MRI Techniques and Applications
- Color perception and design
- Ophthalmology and Eye Disorders
- Gaze Tracking and Assistive Technology
- Glaucoma and retinal disorders
- Visual perception and processing mechanisms
- Urban Transport and Accessibility
- Electron Spin Resonance Studies
- Psychosomatic Disorders and Their Treatments
- Neurobiology of Language and Bilingualism
- Ergonomics and Musculoskeletal Disorders
- Schizophrenia research and treatment
- Acute Ischemic Stroke Management
- Balance, Gait, and Falls Prevention
- Genetic Neurodegenerative Diseases
National Hospital for Neurology and Neurosurgery
2019-2024
University College London
2017-2024
UK Dementia Research Institute
2017-2024
University of Cambridge
2024
University of Manchester
2024
MRC Cognition and Brain Sciences Unit
2024
Institute of Cognitive and Brain Sciences
2021
Max Planck Institute for Human Cognitive and Brain Sciences
2019
Abstract Posterior cortical atrophy is a clinico-radiological syndrome characterized by progressive decline in visual processing and of posterior brain regions. With the majority cases attributable to Alzheimer’s disease recent evidence for genetic risk factors specifically related atrophy, can provide important insights into selective vulnerability phenotypic diversity. The present study describes first major longitudinal investigation progression. Three hundred sixty-one individuals (117...
Purpose High‐resolution quantitative multi‐parameter mapping shows promise for non‐invasively characterizing human brain microstructure but is limited by physiological artifacts. We implemented corrections rigid head movement and respiration‐related B0‐fluctuations evaluated them in healthy volunteers dementia patients. Methods Camera‐based optical prospective motion correction (PMC) FID navigator were a gradient RF‐spoiled multi‐echo 3D echo sequence proton density (PD), longitudinal...
There is increasing theoretical and empirical support for the brain combining multisensory information to determine direction of gravity hence uprightness. A fundamental part process spatial transformation sensory signals between reference frames: eye-centred, head-centred, body-centred, etc. The question 'Am I right way up?' posed by a patient with posterior cortical atrophy (PCA) suggests disturbances in upright perception, subsequently investigated PCA typical Alzheimer's disease (tAD)...
Visual processing deficits in Alzheimer's disease are associated with diminished functional independence. While environmental adaptations have been proposed to promote independence, recent guidance gives limited consideration such and offers conflicting recommendations for people dementia. We evaluated the effects of clutter color contrasts on performances everyday actions posterior cortical atrophy memory-led typical disease.15 patients atrophy, 11 16 healthy controls were asked pick up a...
Alzheimer disease (AD) spans heterogeneous typical and atypical phenotypes. Posterior cortical atrophy (PCA) is a striking example, characterized by prominent impairment in visual other posterior functions contrast to typical, amnestic AD. The primary study objective was establish how the similarities differences of cognition brain volumes within AD PCA (and extension variants) can be conceptualized as systematic variations across transdiagnostic, graded multidimensional space.
The current report describes the journey from sharing of a single, extraordinary experience during support group conversation to development novel scientific investigation balance problems in rarer form dementia. story centres around involvement people living with or caring for someone posterior cortical atrophy (often referred as visual variant Alzheimer’s disease) highlighting hitherto under-appreciated consequences their condition upon ability know ‘Am I right way up?’. We describe how...
Progressive reading impairment is an early and debilitating symptom of posterior cortical atrophy (PCA) arising from the progressive deterioration visual processing skills.The goal this study was to test effectiveness a purpose-built app (ReadClear) co-produced with people living PCA designed reduce difficulties experienced by population (e.g., getting lost in page missing words when reading).Twenty subjects were included cross-over design home-based aimed at determining whether ReadClear...
Importance Understanding the mechanisms of delusion formation in Alzheimer disease (AD) could inform development therapeutic interventions. It has been suggested that delusions arise as a consequence false memories. Objective To investigate whether AD are associated with recognition, and higher rates recognition presence lower regional brain volumes same regions. Design, Setting, Participants Since Alzheimer’s Disease Neuroimaging Initiative (ADNI) launched 2004, it amassed an archive...
Abstract Introduction Clinical reports describe patients with Alzheimer's disease (AD) exhibiting atypical adaptive walking responses to the visual environment; however, there is limited empirical investigation of such behaviors or factors modulating their expression. We aim evaluate effects lighting‐based interventions and clinical presentation (visual‐ vs memory‐led) on function in participants posterior cortical atrophy (PCA) typical AD (tAD). Methods Participants PCA (n = 10), tAD 9),...
Abstract Background Identifying early pathological changes in Alzheimer’s Disease (AD), and accounting for variability progression between individuals, is crucial timely effective intervention. While Amyloid‐b, tau, neuronal loss are core processes AD with established biomarkers, myelin alterations have been shown to occur but remain under‐investigated. The T1/T2w ratio represents an accessible MRI‐based marker, providing a potential proxy measure of integrity. Autosomal dominant (ADAD)...
Dementia-related visual impairments are common but under-recognised; such associated with diminished topographical orientation, autonomy and quality of life. Corticovisual particularly evident in individuals posterior cortical atrophy (PCA), a neurodegenerative syndrome characterised by progressive dysfunction occipito-parietal atrophy. Dementia friendly design guidelines have emphasised the importance characteristics physical environment supporting patient navigational ability. Such...
Abstract PURPOSE High-resolution quantitative multi-parameter mapping shows promise for non-invasively characterizing human brain microstructure but is limited by physiological artifacts. We implemented corrections rigid head movement and respiration-related B0-fluctuations evaluated them in healthy volunteers dementia patients. METHODS Camera-based optical prospective motion correction (PMC) free-induction decay (FID) navigator were a gradient RF-spoiled multi-echo 3D echo sequence proton...
Abstract Background and Objectives Alzheimer’s disease spans heterogeneous typical atypical phenotypes. Posterior cortical atrophy is one striking example, characterised by prominent impairment in visual other posterior functions contrast to typical, amnestic disease. The primary study objective was establish how the similarities differences of cognition brain volumes within (and extension variants), can be conceptualised as systematic variations across a transdiagnostic, graded...
Abstract Background In Alzheimer’s disease (AD), dysfunction and loss of cortical neurons occurs prior to symptom onset. Diffusion tensor imaging, measuring mean diffusivity (MD), provides a metric microscopic change but lacks specificity for different underlying microstructural processes. We used Neurite Orientation Dispersion Density Imaging (NODDI) investigate specific features across the course in autosomal dominant AD (ADAD). Method Sixty‐three ADAD family members (36 mutation carriers)...
Abstract Background In Alzheimer’s disease (AD), dysfunction and loss of cortical neurons occurs prior to symptom onset. Diffusion tensor imaging, measuring mean diffusivity (MD), provides a metric microscopic change but lacks specificity for different underlying microstructural processes. We used Neurite Orientation Dispersion Density Imaging (NODDI) investigate specific features across the course in autosomal dominant AD (ADAD). Method Sixty‐three ADAD family members (36 mutation carriers)...
Abstract Background Cortical grey matter (CGM) and superficial white (SWM) undergo pathological changes, but standard MRI spatial resolutions make interpreting disease‐related effects at their interface challenging. We present findings from a study investigating the grey/white in typical amnestic Alzheimer’s disease (tAD), posterior cortical atrophy (PCA) healthy controls using ultra‐high‐resolution quantitative measures sensitive to microstructural properties. Method Eleven participants...
Abstract Background Posterior cortical atrophy (PCA) is a neurodegenerative syndrome most commonly caused by Alzheimer’s disease (AD) pathology. PCA often considered the canonical ‘visual dementia’, characterised progressive loss of visual and posterior functions corresponding to parieto‐occipital occipito‐temporal atrophy. However, patient reports difficulties finding sleeves clothes, transferring between postures determining heading direction imply non‐visual disturbances, consistent with...
Abstract Background Posterior cortical atrophy (PCA) is a neurodegenerative syndrome most commonly caused by Alzheimer’s disease (AD) and often considered the common atypical AD presentation. PCA characterised predominant visual rather than memory loss occipito‐parietal/occipito‐temporal (‘visual‐spatial AD’). Characteristic visual‐spatial deficits in include difficulty perceiving objects among clutter, consistent with excessive crowding. However, there conflicting guidance limited empirical...
Effective processing of visual information acquired through eye movements plays a crucial role in supporting spatial awareness and object recognition. Locomotion strategies rely on about the proximal environment, but are vulnerable to neurodegeneration caused by conditions such as Alzheimer's disease. Posterior Cortical Atrophy (PCA), which involves pathological changes toward back brain contrast typical Disease (tAD), is characterised deficits processing, praxis relatively spared episodic...
It has been postulated that the development of a dementia-friendly environment can enhance autonomy in Alzheimer's Disease. However, there few studies have investigated this controlled way. Data from wearable sensors provide continuous objective measures performance task activity. Therefore, we created simulated real-world environments, using to evaluate Three groups participants were studied: patients with either Posterior Cortical Atrophy or Disease, and age-matched controls. Simulated...
Posterior cortical atrophy (PCA) is a neurodegenerative condition characterised by progressive corticovisual impairments and pathological involvement of posterior parietal occipito-temporal regions. While Alzheimer's Disease the predominant cause PCA, unlike typical (tAD), episodic memory, executive functions, linguistic skills in individuals with PCA are relatively well-preserved early disease stages. Due to impairment, patients often experience difficulties carrying out everyday tasks...
While corticovisual impairment may manifest in typical Alzheimer's disease (tAD), it is a defining feature of posterior cortical atrophy (PCA) neurodegenerative syndrome characterised by progressive visual dysfunction contrast to relatively preserved episodic memory. Such contributes towards difficulties spatial orientation and navigation, greatly undermining patients’ autonomy. Environmental adaptations have been proposed help maintain the independence people with dementia (National...
Diminished visual search in Posterior Cortical Atrophy (PCA) and typical Alzheimer's disease (tAD) can fundamentally undermine everyday tasks. Previous research suggests the disproportionate influence of conspicuous, visually salient features on gaze (fixation) position PCA patients (Shakespeare et al., 2015). However, there is limited understanding how aspects environment may relate to patient function, such as object localisation navigation. The following study combines kinematic, eye...
Diminished visual search in Posterior Cortical Atrophy (PCA) and typical Alzheimer's disease (tAD) can fundamentally undermine everyday tasks. Previous research suggests the disproportionate influence of conspicuous, visually salient features on gaze (fixation) position PCA patients (Shakespeare et al., 2015). However, there is limited understanding how aspects environment may relate to patient function, such as object localisation navigation. The following study combines kinematic, eye...
Posterior cortical atrophy (PCA) is a clinicoradiological syndrome characterized by progressive visual dysfunction and parietal, occipital occipito-temporal atrophy. PCA has been reported as the most common atypical presentation of Alzheimer's disease (AD), arguably representing striking example AD phenotypic heterogeneity. Previous studies have largely investigated defining aspects syndrome. However, people with disordered balance experiences suggestive impaired integration visual,...