The patient was an 85-year-old man with a one-year history of difficulty reading kana. Neuropsychological evaluation revealed kana (phonogram)-selective reading impairment and kanji (ideogram)-dominant writing impairment. MRI revealed significant cerebral atrophy in the left occipital cortex, leading to the clinical diagnosis of posterior cortical atrophy (PCA). Cerebrospinal fluid amyloid β1-42 levels were reduced, and amyloid PET showed accumulation in the posterior cingulate cortex, precuneus, and frontal lobe. In contrast, tau PET showed no accumulation in the atrophied brain areas. Episodes of REM sleep behavior disorder and decreased uptake on meta-iodobenzylguanidine (MIBG) myocardial scintigraphy suggested the involvement of Lewy body pathology. PCA with distinct laterality has been rarely reported, and ‍this is the first case to present Kana-selective reading impairment and Kanji-dominant writing impairment with neurodegenerative background.

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The WHO Dementia Global Action Plan states that rehabilitation services for dementia are required to promote health, reduce disability, and maintain quality of life for those living with dementia. Current services, however, are scarce, particularly for people with young-onset dementia (YOD). This article, written by an international group of multidisciplinary dementia specialists, offers a three-part overview to promote the development of rehabilitation services for YOD. Firstly, we provide a synthesis of knowledge on current evidence-based rehabilitative therapies for early-onset Alzheimer\'s disease (EOAD), behavioural variant frontotemporal dementia (bvFTD), primary progressive aphasia (PPA), and posterior cortical atrophy (PCA). Secondly, we discuss the characteristics of rehabilitation services for YOD, providing examples across three continents for how these services can be embedded in existing settings and the different roles of the rehabilitation multidisciplinary team. Lastly, we conclude by highlighting the potential of telehealth in making rehabilitation services more accessible for people with YOD. Overall, with this paper, we aim to encourage clinical leads to begin introducing at least some rehabilitation into their services, leveraging existing resources and finding support in the collective expertise of the broader multidisciplinary dementia professional community.

Impairments of object recognition are core features of neurodegenerative syndromes, in particular posterior cortical atrophy (PCA; the \'visual-variant Alzheimer\'s disease\'). These impairments arise from damage to higher-level cortical visual regions and are often missed or misattributed to common ophthalmological conditions. Consequently, diagnosis can be delayed for years with considerable implications for patients. We report a new test for the rapid measurement of cortical visual loss - the Graded Incomplete Letters Test (GILT). The GILT is an optimised psychophysical variation of a test used to diagnose cortical visual impairment, which measures thresholds for recognising letters under levels of increasing visual degradation (decreasing \"completeness\") in a similar fashion to ophthalmic tests. The GILT was administered to UK Biobank participants (total n=2,359) and participants with neurodegenerative conditions characterised by initial cortical visual (PCA, n=18) or memory loss (typical Alzheimer\'s disease, n=9). UK Biobank participants, including both typical adults and those with ophthalmological conditions, were able to recognise letters under low levels of completeness. In contrast, participants with PCA consistently made errors with only modest decreases in completeness. GILT sensitivity to PCA was 83.3% for participants reaching the 80% accuracy cut-off, increasing to 88.9% using alternative cut-offs (60% or 100% accuracy). Specificity values were consistently over 94% when compared to UK Biobank participants without or with documented visual conditions, regardless of accuracy cut-off. These first-release UK Biobank and clinical verification data suggest the GILT has utility in both rapidly detecting visual perceptual losses following posterior cortical damage and differentiating perceptual losses from common eye-related conditions.

BACKGROUND: Supporting ageing in place, quality of life and activity engagement are public health priorities for people living with dementia, but little is known about the needs and experiences of community-dwelling people with rarer forms of dementia with lesser known symptoms. Posterior cortical atrophy (PCA) is a rare form of dementia usually caused by Alzheimer\'s disease but which is characterised by diminished visual processing (rather than a dominant memory problem), which poses challenges for maintaining independence and accessing appropriate support.
METHODS: This study used a comparative qualitative design and focussed ethnographic methods to explore experiential differences in activity engagement for 10 people with the most common, memory-led presentation of Alzheimer\'s disease and 10 people with posterior cortical atrophy within their everyday home environments.
RESULTS: While the data collection revealed much rich variation in individual and contextual factors, some tentative high-level differences in the experiences of everyday activities could be drawn out, seemingly attributable to the different diagnoses\' differing dominant symptoms. These included people with posterior cortical atrophy being less likely to use environmental cues to initiate activities, and more likely to withhold from asking for support because of preserved insight into the impact of this on carers. This lack of initiation of activities could be misinterpreted as apathy. People with posterior cortical atrophy also were discouraged from engaging in activities by disorientation within the home, and difficulties localising, identifying and manipulating objects. People with the more common, memory-led presentation of Alzheimer\'s disease exhibited more memory-based difficulties with engaging with activities such as forgetting planned activities, where to locate the items required for an activity and the steps involved. Despite these distinct symptom-led challenges, all participants and their family members demonstrated resourcefulness and resilience in making creative adaptations to support continued engagement in everyday activities, supporting the widely reported management strategies of people with dementia of the Alzheimer\'s type more generally.
CONCLUSIONS: These findings offer helpful insights into some the differing impacts dementia related visual and memory impairments can have on everyday activity engagement, which will be helpful for others navigating these challenges and the health and social care practitioners working with people affected by these conditions. The findings also highlight the vast individual variation in the multitude of individual and contextual factors involved in everyday activity engagement, and suggest important areas for future work utilising methods which are similarly high in ecological validity and accessibility as the home-based focussed ethnographic methods utilised here.

A research participant was monitored over nearly two decades at Mayo Clinic, undergoing annual neurologic assessments, neuropsychological tests, and multimodal imaging. Initially, he was cognitively normal but developed symptoms consistent with Posterior Cortical Atrophy (PCA) during the study. Early tests indicated mild, yet normal-range declines in language and visuospatial skills. FDG-PET scans revealed increased metabolism in posterior brain regions long before symptoms appeared. Advanced analysis using a novel in-house machine-learning tool predicted concurrent Alzheimer\'s disease and dementia with Lewy bodies. Autopsy confirmed a mixed neurodegenerative condition with significant Alzheimer\'s pathology and dense neocortical Lewy bodies. This case underscores the value of longitudinal imaging in predicting complex neurodegenerative diseases, offering vital insights into the early neurocognitive changes associated with PCA and dementia with Lewy bodies.

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Visual imagery has a close overlapping relationship with visual perception. Posterior cortical atrophy (PCA) is a neurodegenerative syndrome marked by early impairments in visuospatial processing and visual object recognition. We asked whether PCA would therefore also be marked by deficits in visual imagery, tested using objective forced-choice questionnaires, and whether imagery deficits would be selective for certain properties. We recruited four patients with PCA and a patient with integrative visual agnosia due to bilateral occipitotemporal strokes for comparison. We administered a test battery probing imagery for object shape, size, colour lightness, hue, upper-case letters, lower-case letters, word shape, letter construction, and faces. All subjects showed significant impairments in visual imagery, with imagery for lower-case letters most likely to be spared. We conclude that PCA subjects can show severe deficits in visual imagery. Further work is needed to establish how frequently this occurs and how early it can be found.

Posterior Cortical Atrophy (PCA) is a rare form of young-onset dementia that causes early visuospatial and visuoperceptual deficits. The symptom profile of Posterior Cortical Atrophy leads to very specific care needs for those affected, who often rely on informal caregivers (including friends and family). Rare dementia support groups can be useful for both patients and their caregivers to assist with knowledge sharing, psychoeducation, and the provision of psychosocial support. Despite this, few such support groups exist. The purpose of this study was to examine a PCA support group for caregivers of individuals living with PCA. We held a structured psychoeducation support group comprised of four sessions with the aim being to provide education, strategies for the management of the disease, and peer support. Caregivers\' mental health and quality of life were assessed. The results of our study showed that support group participation was a positive experience and assisted with increasing the knowledge of caregivers and fostering social connections. We suggest that peer support groups may be beneficial for both people living with PCA and their caregivers. We recommend that future quantitative and qualitative research is conducted to further assess health-promotion benefits to people living with PCA and their caregivers, and to assess their development and implementation in different contexts.

BACKGROUND: Studies have shown that the prevalence of all-variants Alzheimer\'s disease (AD) and frontotemporal dementia (FTD) both increase with age, even before the age of 65. However, it is not known whether their different clinical presentations all increase in prevalence with age in the same way.
METHODS: We studied the prevalence of the different clinical presentations of young-onset AD and FTD by 5-year age groups in a population-based study identifying all dementia patients with a diagnosis of AD and FTD and symptoms onset before age 65 in the Modena province, Italy. By using regression models of cumulative occurrences, we also estimated age-specific prevalence and compared the growth curves of the clinical presentations.
RESULTS: The prevalence of all-variants AD increased with age, from 18/1,000,000 in the 40-44 age group to 1411/1,000,000 in the 60-64 age group. The prevalence of all-variants FTD also increased with age, from 18/1,000,000 to 866/1,000,000. An estimation of age-specific prevalence functions of each clinical presentation showed that atypical non-amnestic AD and aphasic FTD grew the most in early ages, followed by the behavioural variant of FTD (bvFTD). Then, around the age of 60, amnestic AD took over and its age-specific prevalence continued to increase disproportionally compared to all the other clinical variants of AD and FTD, which, instead, started to decrease in prevalence.
CONCLUSIONS: Amnestic AD is the clinical presentation that increases the most with advancing age, followed by bvFTD, suggesting that there is a differential vulnerability to the effect of ageing within the same neurodegenerative disease.