Posterior Cortical Atrophy (PCA) Programme

The Posterior Cortical Atrophy (PCA) group at the Dementia Research Centre is dedicated to understanding Posterior Cortical Atrophy, a syndrome closely associated with Alzheimer's disease.

PCA presents unique challenges, as individuals affected by this condition encounter difficulties in perceiving and interacting with the world around them due to vulnerability of areas at the back of the brain responsible for processing visual and spatial information. Our research aims to shed light on PCA by conducting comprehensive studies aimed at understanding its causes, improving diagnosis, and providing better support for those living with the condition. 

We undertake a diverse range of investigations which have been prompted by the above challenges experienced by people living with PCA. Investigations include:

Clinical Profiles of PCA: We aim to better understand day-to-day experiences of those living with PCA and to improve clinical assessment through detailed investigations of vision, memory, language, and the ability to navigate and orient to one’s surroundings. 

Our research explores PCA symptoms which suggest altered communication between different sensory systems. These studies aim to better understand participant reports – for example, of altered coordination or balance- to determine underlying mechanisms and to inform targeted interventions.

Imaging/Radiological and Neuropathological Profile of PCA: We aim to identify the unique radiological features associated with PCA to gain insights into the brain changes underlying PCA, its progression and to improve diagnosis. 

To better understand causes of PCA, we investigate underlying pathology: from Alzheimer’s disease, lewy body and other neurodegenerative diseases, to markers of neuroinflammation. 

Support Needs in PCA: Receiving a diagnosis of PCA can have profound implications. We explore the emotional and social effects of diagnosis and aim to develop tools and strategies to offer support and guidance. 

Technology and PCA: Outside imaging techniques, we use a number of technological approaches to advance early detection of PCA and clinical assessment. We also create technology-based aids and tools to support everyday activities.

Current Members:

 

Research Students:

 

Alumni:

  • Zeinab Abdi
  • Kyriaki Mengoudi
  • Ivanna Pavisic
  • Tim Shakespeare
  • Amelia Carton
  • Manja Lehmann

 

Collaborators:

  • Prof John Greenwood
  • Prof Patrick Haggard
  • Prof Tammaryn Lashley
  • Prof Dave Cash
  • Prof Andre Altmann
  • Prof Axel Petzold
  • Prof Paul Foster
  • Dr Jennifer Nicholas
  • Dr Silvia Primativo

  • Vivensa Foundation
  • The National Brain Appeal
  • Alzheimer’s Society
  • Alzheimer’s Research UK
  • Medical Research Council
  • Glaucoma UK

Our group is strongly translationally driven. Our research starts and ends where people living with dementia identify their needs. Some examples of this ethos in the last few years are:

 

‘PCA Tips’: This is a web resource featuring over 150 tips and strategies to help with symptoms of PCA, which is informed by experiences of people living with PCA who have taken part in research at UCL, and who have shared their experiences. 

We will be routinely updating this list and any suggestions you think might be worth adding to the list will be appreciated! 

 

‘ReadClear project’: We co-designed and developed an assistive reading tool along with a group of people living with PCA using a participatory approach.

 

‘Am I the right way up?’: This report describes our group’s experience developing a novel scientific investigation borne out of comments shared by participants in a support group conversation, along with reflections about the multifaceted nature of public involvement.

 

‘Inspired by chance: valuing patients’ informal contributions to research’ This piece of work argues in support of better recognition of independent public contributions to research and proposes five broad classes of PPI.

Publications

The drop-down arrows below provide information about ongoing and recently completed projects. In addition, there are a number of studies which have recently begun or are due to begin soon which intend to improve diagnosis, and better understand and manage PCA symptoms. 

  • Improving detection and diagnosis of PCA 

    This project aims to develop and validate a test to help health professionals assess both “eyesight” (visual input from the eyes) and “brain sight” (how the brain interprets visual information) in individuals with and without PCA. This project involves a test we have developed for UK Biobank, now administered to >50,000 across the UK and internationally.

    We are working to develop a version of this test suitable across eye, neurology and dementia services. Once validated, this tool will form the basis for tailored training and testing packages designed for specific professional audiences, supporting better clinical practice and earlier recognition of PCA-related visual difficulties. We are also investigating reasons behind vulnerability of the brain’s visual networks at UCL and UK Biobank.

  • Investigating altered spatial awareness

    Inspired by clinical reports of early changes in visual perception and spatial awareness in PCA，this project seeks to improve recognition and understanding of these perceptual disturbances. Specifically, we are investigating participant reports suggestive of altered perception of touch and body position. We are investigating what combinations of sensory information are ideal to reliably and confidently perceive where things are in space, with implications for improving assessment and tailored support.  

  • ARUK gait investigations

    We are conducting a study to better understand how individuals navigate everyday environments—such as walking through doorways or along corridors—and to identify factors which influence balance, coordination, and movement. We are particularly interested in how different types of sensory information support these abilities. We are inviting individuals diagnosed with posterior cortical atrophy or Alzheimer’s disease with prominent memory difficulties to take part. Participation is voluntary and involves a week-long period of at-home monitoring using a wearable device to track walking and physical activity.

  • Am I the Right Way Up?" Investigating Balance Problems in Posterior Cortical Atrophy

    This study explored balance problems experienced by people living with Posterior Cortical Atrophy or memory-led Alzheimer’s disease. Balance difficulties in dementia are still poorly understood, yet they can contribute to disorientation and increase the risk of falls. By studying these experiences, the research aimed to improve understanding and inform future ways to support safer movement and independence.
    The study was carried out in collaboration with Professor Brian Day at the Whole-Body Sensorimotor Laboratory in Queen Square. Participants took part in MRI scans, balance assessments, and cognitive tests, helping to build a clearer picture of how dementia affects the body’s control of movement and balance.

  • Read Clear: An App to facilitate reading in Posterior Cortical Atrophy

    Reading is a vital part of daily life — essential for learning, communication, and connection. People living with Posterior Cortical Atrophy often experience visuospatial and perceptual difficulties that disrupt reading from the earliest stages of the disease, with many describing this loss as one of its most distressing effects.

    For over a decade, our group has investigated the mechanisms underlying reading impairment in Posterior Cortical Atrophy, with the goal of finding ways to preserve this important skill. This work led to the development of ReadClear, a software-based reading tool co-designed with people living with Posterior Cortical Atrophy. ReadClear aims to reduce visual disorientation, crowding, and oculomotor difficulties, helping users read more comfortably and accurately, and to restore some of the enjoyment that reading brings. The app can be downloaded here.

  • Seeing what they see: compensating for cortical visual dysfunction in Alzheimer’s disease

    People with Posterior Cortical Atrophy often experience problems seeing what and where things are, even though their eyes are healthy. These difficulties are frequently misunderstood or attributed to memory loss.

    This project aimed to better understand how Posterior Cortical Atrophy and related forms of Alzheimer’s disease affect vision and everyday life. By studying how people with Posterior Cortical Atrophy saw and interact with their surroundings, we sought to identify simple environmental changes and visual aids — such as improved lighting or colour contrast — that could make daily activities easier and safer.

    Working with people living with Posterior Cortical Atrophy, memory-led Alzheimer’s disease, and healthy volunteers, the study assessed how these visual strategies influenced quality of life and wellbeing for both individuals and their carers. Bringing together experts in dementia, engineering, social science, and eye health, the project developed practical, person-centred ways to support those living with Posterior Cortical Atrophy.

  • Longitudinal neuroanatomical and cognitive progression of posterior cortical atrophy

    This project was the first large study to follow people with Posterior Cortical Atrophy over several years to understand how the condition changes over time. More than 100 people with Posterior Cortical Atrophy, alongside others with memory-led Alzheimer’s disease and healthy volunteers, took part in annual visits that included brain scans and thinking tests at centres in the UK, Spain, and the US.

    Working with Professor Daniel Alexander’s team at UCL’s Centre for Medical Image Computing, we looked at how different parts of the brain change as PCA progresses. Because most cases of Posterior Cortical Atrophy are caused by Alzheimer’s disease, these findings are helping researchers understand why the same disease can affect people in such different ways — and why some areas of the brain are more vulnerable than others.

  • Understanding the everyday experiences of people living with visual and memory-led dementias

    We carried out two home-based studies to better understand how Posterior Cortical Atrophy affects daily life. Through interviews, walk-around tours, and observations, we explored the challenges people face in their own homes, the coping strategies they use, and ways support could be improved for those living with dementia-related visual impairment.

    Findings revealed the often complex path to diagnosis, difficulties with everyday activities such as dressing, eating, reading, and navigation, and the emotional impact of growing dependence and loss of confidence. Yet, many families showed remarkable creativity and adaptability, developing their own strategies to maintain independence and engagement in meaningful activities. We are now exploring in greater depth how these activities are adapted and sustained by people living with Posterior Cortical Atrophy.

  • Ultra-high resolution MRI study in Posterior Cortical Atrophy and Alzheimer’s disease

    This was the first study to use an ultra-high-resolution 7-Tesla MRI scanner to investigate brain changes associated with Posterior Cortical Atrophy without the need for invasive methods. The study aimed to determine whether such changes can be detected much earlier than previously possible, and how they differ across various forms of Alzheimer’s disease.

    Understanding Alzheimer’s disease requires detailed insight into how it alters the brain’s microstructure. Until now, this has only been achievable through invasive techniques or post-mortem examination. However, new ultra-high-resolution MRI scanners and advanced imaging methods now provide exceptionally detailed pictures of the brain, allowing researchers to identify the subtle structural changes caused by the disease during life.

  • Play It Again: Responses to music

    This study explored how subtle physical responses — such as changes in heart rate, skin temperature, or pupil size — relate to the way we describe and emotionally respond to music. We invited people living with Posterior Cortical Atrophy or memory-led Alzheimer’s disease to listen to music while their reactions were recorded using discreet wearable sensors and a camera. Participants also shared their musical preferences and took part in short language and thinking tasks.

    Play It Again reflects our ongoing interest in the role of the arts in the lives of people with dementia, and how creative experiences can reveal and support emotional connection and self-expression.
     

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Interested in taking part?

If you are interested in hearing about opportunities to be involved in PCA research, please feel free to contact Dr Keir Yong (keir.yong@ucl.ac.uk) and Yuhan Bai (yuhan.bai.22@ucl.ac.uk).