-
Radiologia 2018Aphasia is an acquired language disorder due to a cerebral lesion; it is characterized by errors in production, denomination, or comprehension of language. Although most... (Review)
Review
Aphasia is an acquired language disorder due to a cerebral lesion; it is characterized by errors in production, denomination, or comprehension of language. Although most aphasias are mixed, from a practical point of view they are classified into different types according to their main clinical features: Broca's aphasia, Wernicke's aphasia, conduction aphasia, transcortical aphasia, and alexia with or without agraphia. We present the clinical findings for the main subtypes of aphasia, illustrating them with imaging cases, and we provide an up-to-date review of the language network with images from functional magnetic resonance imaging and tractography.
Topics: Aphasia; Cerebral Cortex; Diffusion Tensor Imaging; Humans; Magnetic Resonance Imaging; Neuroimaging
PubMed: 29439808
DOI: 10.1016/j.rx.2017.12.008 -
Current Neurology and Neuroscience... Aug 2020Gerstmann (left angular gyrus) syndrome includes the tetrad of finger agnosia (inability to distinguish, name, and recognize the fingers), agraphia (acquired disturbance... (Review)
Review
PURPOSE OF REVIEW
Gerstmann (left angular gyrus) syndrome includes the tetrad of finger agnosia (inability to distinguish, name, and recognize the fingers), agraphia (acquired disturbance in the ability to write), acalculia (loss of the ability to perform arithmetical operations and use numerical concepts), and right-left disorientation (right-left discrimination defect when using language). There is some disagreement regarding its exact localization, but it most likely involves the left angular gyrus with a probable subcortical extension. This article reviews recent research on the clinical aspects of this syndrome.
RECENT FINDINGS
During the last years, just some few new reports of Gerstmann syndrome are found in neurological and neuropsychological literature. Most of the reports are single-case reports. An association between Gerstmann syndrome and the so-called semantic aphasia has been pointed out. Two different explanations to this unusual syndrome have been recently proposed: (1) the pathological process is located in the left parietal white matter disconnecting separate cortical networks and (2) it represents a disturbance in the ability to verbally mediate some spatial knowledge. Although Gerstmann syndrome continues as a controversial syndrome, and most of the reports are single case reports, recently two different explanations have been advance the understanding of this polemic but fascinating syndrome.
Topics: Agnosia; Gerstmann Syndrome; Humans
PubMed: 32852667
DOI: 10.1007/s11910-020-01069-9 -
Archives of Clinical Neuropsychology :... May 2021Patients with aphasia can present a type of acalculia referred to as aphasic acalculia.
BACKGROUND
Patients with aphasia can present a type of acalculia referred to as aphasic acalculia.
AIMS
To investigate the correlation and to test regression models for one- and two-digit calculation skills using verbal and nonverbal predictors.
METHODS AND PROCEDURES
We selected an aphasia sample of 119 men and 81 women with a mean age of 57.37 years (SD = 15.56) and an average level of education of 13.52 years (SD = 4.08). Spanish versions of the Western Aphasia Battery and Boston Diagnostic Aphasia Examination, plus a Written Calculation test, were individually administered. The calculation section of the Western Aphasia Battery and the Written Calculation tests were used to pinpoint calculation difficulties.
OUTCOMES AND RESULTS
Calculation difficulties were more severe in Global and Mixed non-fluent aphasia; they were very similar in Broca, Conduction, and Amnesic Aphasia. All correlations between the two calculation subtests and the other subtests of the Western Aphasia Battery were statistically significant. Calculation subtests correlated negatively with age and positively with schooling. Sex and time post-onset did not show any correlation with the calculation scores. Education, Reading, Block Design, and Raven's Colored Progressive Matrices were significant predictors of Western Aphasia Battery Calculation. Writing was the only significant predictor of the Written Calculation scores.
CONCLUSIONS
Nonverbal abilities were predictors of calculation tests, whereas agraphia defects were predictors of the Written Calculation test. Therefore, calculation abilities can be regarded both as written language-dependent and verbal language-independent.
Topics: Aphasia; Dyscalculia; Educational Status; Female; Humans; Language; Male; Middle Aged; Neuropsychological Tests
PubMed: 32978628
DOI: 10.1093/arclin/acaa072 -
Frontiers of Neurology and Neuroscience 2019Studies of alexia and agraphia have played historically important roles in efforts to understand the relation between brain and behavior. In the second half of the 19th... (Review)
Review
Studies of alexia and agraphia have played historically important roles in efforts to understand the relation between brain and behavior. In the second half of the 19th century, works by Paul Broca and Carl Wernicke led to the concept of delimited cortical centers in the left cerebral hemisphere concerned with discrete aspects of spoken and written language. These specialized centers were linked by white matter pathways. Charlton Bastian, Jean-Martin Charcot, Sigmund Exner, and Jules Dejerine championed center-pathway models of reading and writing. Dejerine played a dominant role, rejecting the idea of a left frontal lobe center that mediated writing and proposing a unique, specialized role for the left angular gyrus in both reading and writing. In 1891 and 1892, he detailed the symptoms of alexia and agraphia that resulted from injury to the left angular gyrus and from the isolation of the left angular gyrus from visual input required for reading. During the early 20th century, his work and that of other so-called diagram makers was confronted and largely discredited by Pierre Marie, joined later by Henry Head and Kurt Goldstein. In the 1960s, the center-pathway model was resurrected and refined by Norman Geschwind. He drew upon foundational works of Dejerine, Hugo Liepmann, and others to describe syndromes resulting from cortical disconnections and, in doing so, helped to establish a framework for the modern discipline of behavioral neurology.
Topics: Agraphia; Dyslexia; History, 19th Century; History, 20th Century; Humans; Neurology; Research
PubMed: 31220840
DOI: 10.1159/000494951 -
Handbook of Clinical Neurology 2021Alexia refers to a reading disorder caused by some form of acquired brain pathology, most commonly a stroke or tumor, in a previously literate subject. In...
Alexia refers to a reading disorder caused by some form of acquired brain pathology, most commonly a stroke or tumor, in a previously literate subject. In neuropsychology, a distinction is made between central alexia (commonly seen in aphasia) and peripheral alexia (a perceptual or attentional deficit). The prototypical peripheral alexia is alexia without agraphia (pure alexia), where patients can write but are impaired in reading words and letters. Pure alexia is associated with damage to the left ventral occipitotemporal cortex (vOT) or its connections. Hemianopic alexia is associated with less extensive occipital damage and is caused by a visual field defect, which creates problems reading longer words and passages of text. Reading impairment can also arise due to attentional deficits, most commonly following right hemisphere or bilateral lesions. Studying patients with alexia, along with functional imaging studies of normal readers, has improved our understanding of the neurobiological processes involved in reading. A key question is whether an area in the left ventral occipitotemporal cortex is specialized for or selectively involved in word processing, or whether reading relies on tuning of more general purpose perceptual areas. Reading deficits may also be observed in dementia and traumatic brain injury, but often with less consistent deficit patterns than in patients with focal lesions.
Topics: Cerebral Cortex; Dyslexia; Humans; Stroke
PubMed: 33832678
DOI: 10.1016/B978-0-12-821377-3.00010-6