Progressive Agraphia, Acalculia, and Anomia: A Single Case Report

The Cognitive Makeup of Writing: Multivariate Analysis of Writing Impairments Following Stroke

Writing is a recently acquired skill to human behavioral repertoire, essential in industrialized societies. In the clinic, writing impairment is evident in one-third of stroke patients. This study aimed to find out the cognitive features that contribute to writing impairment of stroke patients in two different writing systems (logographic and phonological). Cognitive profiles were assessed using the Birmingham Cognitive Screen in two cohorts, China (244 patients) and UK (501 patients). The datasets were analyzed separately using an identical procedure. Elastic net was used to rank the importance of different cognitive abilities (features) to writing skill; and linear support vector machine was used to identify the discriminative features needed to accurately identify the stroke patients with and without writing impairments. The prediction performance was evaluated with the area under the curve (AUC), accuracy (ACC), sensitivity (SEN), and specificity (SPE). For the China cohort, writing numbers, complex figure copy, and number calculation obtained good prediction performance on writing impairments with AUC 0.85 ± 0.06, ACC (89 ± 3) %, SEN (81 ± 10) %, and SPE (90 ± 27) %. Concerning the UK data, writing numbers, number calculation, non-word reading, and auditory sustain attention achieved AUC 0.79 ± 0.04, ACC (83 ± 3) %, SEN (74 ± 9) %, and SPE (84 ± 3) %. A small number of patients in both cohorts (China: 9/69, UK: 24/137), who were impaired in writing, were consistently misclassified. Two patients, one in each cohort, showed selective impairments in writing, while all remaining patients were impaired in attention, language, and/or praxis tasks. The results showed that the capability to write numbers and manipulate them were critical features for predicting writing abilities across writing systems. Reading abilities were not a good predictor of writing impairments across both cohorts. Constructive praxis (measured by complex figure copy) was relevant to impairment classification in characters-based writing (China), while phonological abilities (measured by non-word reading) were important features for impairment prediction in alphabetic writing (UK). A small proportion minority of cases with writing deficits were related to different impairment profiles. The findings in this study highlight the multifaceted nature of writing deficits and the potential use of computation methods for revealing hidden cognitive structures in neuropsychological research.

Handwriting Changes in Alzheimer's Disease: A Systematic Review

BACKGROUND

Handwriting is a complex process involving fine motor skills, kinesthetic components, and several cognitive domains, often impaired by Alzheimer's disease (AD).

OBJECTIVE

Provide a systematic review of handwriting changes in AD, highlighting the effects on motor, visuospatial and linguistic features, and to identify new research topics.

METHODS

A search was conducted on PubMed, Scopus, and Web of Science to identify studies on AD and handwriting. The review followed PRISMA norms and analyzed 91 articles after screening and final selection.

RESULTS

Handwriting is impaired at all levels of the motor-cognitive hierarchy in AD, particularly in text, with higher preservation of signatures. Visuospatial and linguistic features were more affected. Established findings for motor features included higher variability in AD signatures, higher in-air/on-surface time ratio and longer duration in text, longer start time/reaction time, and lower fluency. There were conflicting findings for pressure and velocity in motor features, as well as size, legibility, and pen lifts in general features. For linguistic features, findings were contradictory for error patterns, as well as the association between agraphia and severity of cognitive deficits.

CONCLUSIONS

Further re-evaluation studies are needed to clarify the divergent results on motor, general, and linguistic features. There is also a lack of research on the influence of AD on signatures and the effect of AD variants on handwriting. Such research would have an impact on clinical management (e.g., for early detection and patient follow-up using handwriting tasks), or forensic examination aimed at signatory identification.

The Progressive Acalculia Presentation of Parietal Variant Alzheimer's Disease

BACKGROUND

Many patients with early-onset Alzheimer's disease (EOAD; age of onset <65 years) have non-amnestic presentations involving language (logopenic primary progressive aphasia, lvPPA), visuospatial abilities (posterior cortical atrophy, PCA), and even asymmetric symptoms consistent with corticobasal syndrome (CBS). An inferior parietal lobule variant of EOAD commonly presents with progressive difficulty with calculations.

METHODS

We reviewed 276 EOAD patients for presentations with predominant acalculia. These patients were diagnosed with clinically probable Alzheimer's disease (AD) verified by positron emission tomography (PET) or cerebrospinal fluid amyloid-β or tau biomarkers.

RESULTS

We identified 18 (9M/9F) (6.5%) EOAD patients with progressive acalculia that did not meet most criteria for lvPPA, visual PCA, or CBS. Their ages of onset and presentation were 56.6 (5.0) and 59.4 (6.5), respectively. Their acalculia was consistent with a primary acalculia ("anarithmetia") not explained by language or visuospatial impairments. Many also had anomia (14/18), ideomotor apraxia (13/18), and the complete Gerstmann's syndrome (7/18). Visual analysis of their diverse magnetic resonance imaging disclosed biparietal atrophy, disproportionately worse on the left.

CONCLUSIONS

Primary acalculia may be the most common manifestation of an inferior parietal presentation of EOAD affecting the left intraparietal sulcus. This parietal variant also commonly involves progressive anomia, ideomotor apraxia, and other elements of Gerstmann's syndrome. The early recognition of patients with this variant, which is distinguishable from lvPPA, visual PCA, or CBS, would be facilitated by its recognition as a unique subtype of EOAD.

The benefits and protective effects of behavioural treatment for dysgraphia in a case of primary progressive aphasia

BACKGROUND: Spoken and written language difficulties are the predominant symptoms in the progressive neurodegenerative disease referred to as primary progressive aphasia (PPA). There has been very little research on the effectiveness of intervention on spoken language impairments in this context and none directed specifically at progressive written language impairment. AIMS: To examine the effectiveness of behavioural intervention for dysgraphia in a case of primary progressive aphasia. METHODS #ENTITYSTARTX00026; PROCEDURES: We carried out a longitudinal single-case study that allowed us to examine the effectiveness of a non-intensive spell-study-spell intervention procedure. We did so by comparing performance on four sets of words: trained, repeated, homework, and control words at five evaluations: baseline, during intervention, after the intervention, and at 6- and 12-month follow-up. OUTCOMES #ENTITYSTARTX00026; RESULTS: We find that: (1) at the end of the intervention, Trained words show a small but statistically significant improvement relative to baseline and an advantage in accuracy over Control, Homework, and Repeated word sets. (2) All word sets exhibited a decline in accuracy from the end of treatment to the 6-month follow-up evaluation, consistent with the degenerative nature of the illness. Nonetheless, accuracy on Trained words continued to be superior to that of Control words and not statistically different from pre-intervention baseline levels. (3) Repeated testing and practice at home yielded modest numerical advantages relative to Control words; but these differences were, for many comparisons, not statistically significant. (4) At 12 months post-intervention, all words sets had significantly declined relative to pre-intervention baselines and performance on the four sets was comparable. CONCLUSIONS: This investigation documents-for the first time-that behavioural intervention can provide both immediate and short-term benefits for dysgraphia in the context of primary progressive aphasia.

Progressive agraphia can be a harbinger of degenerative dementia

By investigating three patients with progressive agraphia, we explored the possibility that this entity is an early sign of degenerative dementia. Initially, these patients complained primarily of difficulties writing Kanji (Japanese morphograms) while other language and cognitive impairments were relatively milder. Impairments in writing Kana (Japanese syllabograms), verbal language, executive function, visuo- and visuospatial cognition and memory were identified by neuropsychological testing. The agraphia was compatible with a peripheral type, based on deficits at the interface between the central letter selection and the graphemic motor execution (Patient 1) or at the stage of central letter selection as well (Patients 2 and 3). Agraphia was generally more prominent, although not exclusive, for Kanji probably because of later acquisition and larger total number of Kanji letters leading to lower frequency of use and familiarity per letter. Concurrent or subsequent emergence of non-fluent aphasia, ideomotor apraxia, executive dysfunction and asymmetric akinetic-rigid syndrome in two patients suggested degenerative processes involving the parietal-occipital-temporal regions, basal ganglia and striato-frontal projections. We propose that progressive agraphia may be one of the early symptoms of degenerative dementia such as corticobasal degeneration.

"Apperceptive" alexia in posterior cortical atrophy

The most common presenting complaint in posterior cortical atrophy (PCA) is reading difficulty. Although often described as an alexia without agraphia, alexia in PCA may have multiple causes, including a primary visuoperceptual etiology, attentional alexia, and central reading difficulty. This study evaluated 14 patients with early PCA and disturbances in reading ability in comparison to 14 normal controls. All 14 patients had a progressive disorder of complex visual functions and neuroimaging evidence of occipitoparietal dysfunction. They underwent a task requiring identification of single letters with and without flanking distractors. They also read single words consisting of regular English spelling or irregular grapheme-phoneme correspondence (irregular words) and pronounceable nonsense words (pseudowords). The PCA patients made errors in letter identification when letters were flanked by visually similar letters or numbers. They could read most single regular and irregular words but made visual errors and had particular trouble with pseudowords. They could not use a letter-by-letter reading strategy effectively. The PCA patients had similar difficulties on other visuoperceptual tests. These findings are consistent with an alexia manifested by perceptual and attentional difficulty on attempting serial visual processing of letters in the context of other letters. This "apperceptive alexia" results when the configuration of letters into words is impaired during letter-by-letter reading. Disproportionate difficulty reading pseudowords suggests an additional impairment in phonological processing. PCA patients have variable neuropathology and individual patients may have other contributions to their reading impairment.