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Alexia

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Rhonda B. Friedman – One of the best experts on this subject based on the ideXlab platform.

  • on Rapid Word Identification in Pure Alexia Is Lexical but Not Semantic
    , 2015
    Co-Authors: Rhonda B. Friedman, Susan Nitzberg Lott

    Abstract:

    Following the notion that patients with pure Alexia have access to two distinct reading strategies—letter-by-letter reading and semantic reading—a training pro-gram was devised to facilitate reading via semantics in a patient with pure Alexia. Training utilized brief stimulus presentations and required category judgments rather than explicit word identification. The training was successful for trained words, but generalized poorly to untrained words. Additional studies involving oral reading of nouns and of functors also resulted in improved reading of trained words. Pseudowords could not be trained to criterion. The results suggest that improved reading can be achieved in pure Alexia by pairing rapidly presented words with feedback. Focusing on semantic processing is not essential to this process. It is proposed that the training strengthens connections between the output of visual pro-cessing and preexisting orthographic representations. ª 2000 Academic Press Key Words: pure Alexia; reading treatment; acquired Alexia; semantic reading. In pure Alexia, also known as Alexia without agraphia, spelling and the recognition of orally spelled words remain intact. The reading problem ap-pears to reflect an inability of visual input to activate orthographic word forms. Another term for the disorder, ‘‘letter-by-letter reading,’ ’ comes from the frequently observed behavior in which the patient names each letter in left-to-right order prior to decoding the word. This decoding strategy results in a clear length effect, a hallmark of the disorder, in which words with more letters take longer to read and are more likely to be misread than words with fewer letters

  • multiple oral re reading treatment for Alexia the parts may be greater than the whole
    Neuropsychological Rehabilitation, 2010
    Co-Authors: Elizabeth H Lacey, Susan Nitzberg Lott, Sarah Snider, Anne J Sperling, Rhonda B. Friedman

    Abstract:

    This study examines the reasons for the success of Multiple Oral Re-reading (MOR; Moyer, 1979), a non-invasive, easily administered Alexia treatment that has been reported in the literature and is currently in clinical use. The treatment consists of reading text passages aloud multiple times a day. Findings that MOR improves reading speed on practised as well as novel text have been inconsistent, making MOR’s role in the rehabilitation of Alexia unclear. We hypothesised that MOR’s treatment mechanism works through repetition of high frequency words (i.e., bottom-up processing). We designed and controlled our text passages to test the hypothesis that participants would not improve on all novel text but would improve on text that includes a critical mass of the words contained in the passages they were re-reading. We further hypothesised that the improvement would be at the level of their specific alexic deficit. We tested four participants with phonological Alexia and two with pure Alexia during 8 weeks of MOR treatment. Contrary to the conclusions of previous studies, our results indicate that improvements in top-down processing cannot explain generalisation in MOR and that much of the improvement in reading is through repetition of the practised words. However, most patients also showed improvement when specific phrases were re-used in novel passages, indicating that practice of difficult words in context may be crucial to reading improvement.

  • Multiple oral re-reading treatment for Alexia: It works, but why?
    Brain and Language, 2007
    Co-Authors: Elizabeth H Lacey, Susan Nitzberg Lott, Sarah Snider, Anne J Sperling, Rhonda B. Friedman

    Abstract:

    In the Multiple Oral Re-reading (MOR) technique (Moyer, 1979), patients with Alexia are asked to practice reading aloud simple text passages multiple times for a set number of days. Speed of reading practiced and unpracticed passages is recorded. Although Moyer initially reported improved reading of unpracticed text for a patient with pure Alexia (PA), MOR’s role in the rehabilitation of Alexia remains unclear in light of equivocal findings in subsequent studies (Moody, 1988; Tuomainen & Laine, 1991; Beeson & Insalaco, 1998). Conflicting results in these studies were possibly due to applying MOR to different types of Alexia and to insufficient control of stimuli. We sought to remedy this in the current study by developing tightly controlled text passages to address questions of how and on what type of words the MOR technique might be having its effect, and for what type(s) of Alexia.

Marlene Behrmann – One of the best experts on this subject based on the ideXlab platform.

  • Number reading in pure Alexia — A review
    , 2018
    Co-Authors: Randi Starrfelt, Marlene Behrmann

    Abstract:

    It is commonly assumed that number reading can be intact in patients with pure Alexia, and that this dissociation between letter/word recognition and number reading strongly constrains theories of visual word processing. A truly selective deficit in letter/word processing would strongly support the hypothesis that there is a specialized system or area dedicated to the processing of written words. To date, however, there has not been a systematic review of studies investigating number reading in pure Alexia and so the status of this assumed dissociation is unclear. We review the literature on pure Alexia from 1892 to 2010, and find no well-documented classical dissociation between intact number reading and impaired letter identification in a patient with pure Alexia. A few studies report strong dissociations, with number reading less impaired than letter reading, but when we apply rigorous statistical criteria to evaluate these dissociations, the difference in performance across domains is not statistically significant. There is a trend in many cases of pure Alexia, however, for number reading to be less affected than letter identification and word reading. We shed new light on this asymmetry by showing that, under conditions of brief exposure, normal participants are also better at identifying digits than letters. We suggest that the difference observed in some pure alexic patients may possibly reflect an amplification of this normal difference in the processing of letters and digits, and we relate this asymmetry to intrinsic differences between the two types of symbols.

  • Perceptual Cues in Pure Alexia
    , 2018
    Co-Authors: Erica B. Sekuler, Marlene Behrmann

    Abstract:

    This study provides evidence that pure Alexia, or letter-by-letter reading, may be attributed to a general perceptual deficit that extends beyond an orthographic disorder. The perceptual problem may be unmasked when appropriate perceptual cues are not available to aid in the derivation of an integrated structural description. Four pure alexic patients and eight nonbrain-damaged controls participated in this study. In the first two experiments, subjects’ reading abilities were assessed on a naming latency and a lexical decision task. Experiment 3 replicated Farah and Wallace’s (1991) results that the pure Alexia deficit was not specific to orthography. Experiments 4 and 5 further explored the nature of the perceptual disorder using nonorthographic stimuli. In Experiment 4, patient performance on a target detection task was unaOEected by the number of parts comprising the object but was impaired when the perceptual cue of good continuation was absent. Patient performance also declined when the perceptual cue of symmetry was not available to aid in the integration of occluded object parts in Experiment 5. Overall, the results imply that pure Alexia is most likely to arise from a more general, nonorthographic deficit, and that the nature of the disorder is revealed when the perceptual context lacks strong perceptual cues

  • bilateral hemispheric processing of words and faces evidence from word impairments in prosopagnosia and face impairments in pure Alexia
    Cerebral Cortex, 2014
    Co-Authors: Marlene Behrmann, David C Plaut

    Abstract:

    Considerable research has supported the view that faces and words are subserved by independent neural mechanisms located in the ventral visual cortex in opposite hemispheres. On this view, right hemisphere ventral lesions that impair face recognition (prosopagnosia) should leave word recognition unaffected, and left hemisphere ventral lesions that impair word recognition (pure Alexia) should leave face recognition unaffected. The current study shows that neither of these predictions was upheld. A series of experiments characterizing speed and accuracy of word and face recognition were conducted in 7 patients (4 pure alexic, 3 prosopagnosic) and matched controls. Prosopagnosic patients revealed mild but reliable word recognition deficits, and pure alexic patients demonstrated mild but reliable face recognition deficits. The apparent comingling of face and word mechanisms is unexpected from a domain-specific perspective, but follows naturally as a consequence of an interactive, learning-based account in which neural processes for both faces and words are the result of an optimization procedure embodying specific computational principles and constraints.

Yasuhisa Sakurai – One of the best experts on this subject based on the ideXlab platform.

  • kanji morphogram and kana phonogram problem in japanese Alexia and agraphia
    Frontiers of neurology and neuroscience, 2019
    Co-Authors: Yasuhisa Sakurai

    Abstract:

    : The kanji and kana (or kanji vs. kana) problem in the Japanese language denotes the dissociation between kanji (morphograms) and kana (phonograms) in reading/comprehension and writing. Since paragraphia of kana in a patient with amyotrophic lateral sclerosis was first reported in 1893, kanji-kana dissociation has been the central topic in Japanese aphasiology. Recent advancements in lesion-to-symptom analyses and functional imaging studies have identified some areas whose damage causes dissociative disturbances of reading or writing between kanji and kana. That is, (1) angular Alexia with agraphia causes kanji agraphia; Alexia of kana with an angular gyrus lesion is the result of a damage to the middle occipital gyrus; (2) Alexia with agraphia for kanji is caused by a posterior inferior temporal cortex (mid-fusiform/inferior temporal gyri; visual word form area) lesion, whereas pure agraphia for kanji is caused by a posterior middle temporal gyrus lesion; and (3) pure Alexia, particularly for kanji, results from a mid-fusiform gyrus lesion (Brodmann’s Area [BA] 37), whereas pure Alexia for kana results from a posterior fusiform/inferior occipital gyri lesion (BA 18/19).

  • Lesion localization of non-aphasic Alexia and agraphia
    Rinshō shinkeigaku Clinical neurology, 2011
    Co-Authors: Yasuhisa Sakurai

    Abstract:

    : The author reviews the lesion localization of non-aphasic Alexia and agraphia and proposes a new classification of Alexia and agraphia on this basis. The newly proposed Alexia and agraphia are pure Alexia for kana (Japanese phonograms), or more generally pure Alexia for letters, caused by a lesion in the posterior occipital area (posterior fusiform/inferior occipital gyri), and pure agraphia for kanji (Japanese morphograms) caused by a lesion in the posterior middle temporal gyrus and also a lesion restricted to the angular gyrus. In addition, the anatomical lesions presumably responsible for the parietal apraxic agraphia, frontal pure agraphia and thalamic agraphia are discussed.

  • agraphia for kanji resulting from a left posterior middle temporal gyrus lesion
    Behavioural Neurology, 2008
    Co-Authors: Yasuhisa Sakurai, Imari Mimura, Toru Mannen

    Abstract:

    Objective: To clarify whether agraphia or Alexia occurs in lesions of the left posterior middle temporal gyrus. Methods: We assessed the reading and writing abilities of two patients with this lesion using kanji (Japanese morphograms) and kana (Japanese syllabograms). Results: Patient 1 first presented with pure Alexia more impaired for kana after an infarction in the left middle and inferior occipital gyri and right basal occipital cortex, and after a second infarction in the left posterior middle temporal gyrus adjoining the first lesion he showed Alexia with agraphia for kanji and worsened Alexia for kana; kanji Alexia recovered over the following six to 10 months. Patient 2 presented with Alexia with agraphia for kanji following a hemorrhage in the left posterior middle and inferior temporal gyri, which resolved to agraphia for kanji at two months after onset. Kana nonword reading was also slightly impaired, but became normal by six months post-onset. In both patients, kanji agraphia was mostly due to impaired character recall. Conclusion: The present patients demonstrate that damage to the left posterior middle temporal gyrus alone can cause agraphia for kanji. If the adjacent mid fusiform/inferior temporal gyri (Area 37) are spared, the kanji Alexia is transient.