scholarly journals Developmental dyslexia: Gray matter abnormalities in the occipitotemporal cortex

2008 ◽  
Vol 29 (5) ◽  
pp. 613-625 ◽  
Author(s):  
Martin Kronbichler ◽  
Heinz Wimmer ◽  
Wolfgang Staffen ◽  
Florian Hutzler ◽  
Alois Mair ◽  
...  
2019 ◽  
Author(s):  
Carol Whitney ◽  
Paddy Ross ◽  
Zhiheng Zhou ◽  
Lars Strother

The Visual Word Form Area (VWFA) is a cortical region that adapts to support fluent word recognition. Surprisingly, the region of ventrolateral occipitotemporal cortex that becomes VWFA is specialized for processing the motion of inanimate objects that change shape. Such motion is neurally analyzed as a temporal sequence of shape 'snapshots'. We have proposed that the VWFA develops in this region because letter representations are serially activated in occipitotemporal cortex during typical reading acquisition. Therefore, the region that analyzes inanimate shape sequences is recruited to recognize letter sequences. We discuss the implications of this account for developmental dyslexia. In particular, inability to focus attention down to a single letter may preclude the serial letter selection that typically drives VWFA formation. Such a deficit would also interfere with acquisition of cortical letter-phoneme connections. Instead, compensated dyslexics employ the ventromedial object-recognition system for whole-word recognition, and the subcortical procedural system for phonological decoding.


2008 ◽  
Vol 46 (13) ◽  
pp. 3170-3178 ◽  
Author(s):  
C. Steinbrink ◽  
K. Vogt ◽  
A. Kastrup ◽  
H.-P. Müller ◽  
F.D. Juengling ◽  
...  

2019 ◽  
Vol 60 (4) ◽  
pp. 1063 ◽  
Author(s):  
Ana Pina Rodrigues ◽  
José Rebola ◽  
Marcelino Pereira ◽  
Marieke van Asselen ◽  
Miguel Castelo-Branco

2013 ◽  
Vol 219 (3) ◽  
pp. 1041-1054 ◽  
Author(s):  
Tanya M. Evans ◽  
D. Lynn Flowers ◽  
Eileen M. Napoliello ◽  
Guinevere F. Eden

2021 ◽  
Author(s):  
Valentina Borghesani ◽  
Cheng Wang ◽  
Christa Watson ◽  
Florence Bouhali ◽  
Eduardo Caverzasi ◽  
...  

Author(s):  
Steven M. Le Vine ◽  
David L. Wetzel

In situ FT-IR microspectroscopy has allowed spatially resolved interrogation of different parts of brain tissue. In previous work the spectrrscopic features of normal barin tissue were characterized. The white matter, gray matter and basal ganglia were mapped from appropriate peak area measurements from spectra obtained in a grid pattern. Bands prevalent in white matter were mostly associated with the lipid. These included 2927 and 1469 cm-1 due to CH2 as well as carbonyl at 1740 cm-1. Also 1235 and 1085 cm-1 due to phospholipid and galactocerebroside, respectively (Figs 1and2). Localized chemical changes in the white matter as a result of white matter diseases have been studied. This involved the documentation of localized chemical evidence of demyelination in shiverer mice in which the spectra of white matter lacked the marked contrast between it and gray matter exhibited in the white matter of normal mice (Fig. 3).The twitcher mouse, a model of Krabbe’s desease, was also studied. The purpose in this case was to look for a localized build-up of psychosine in the white matter caused by deficiencies in the enzyme responsible for its breakdown under normal conditions.


Author(s):  
Manuel Perea ◽  
Victoria Panadero

The vast majority of neural and computational models of visual-word recognition assume that lexical access is achieved via the activation of abstract letter identities. Thus, a word’s overall shape should play no role in this process. In the present lexical decision experiment, we compared word-like pseudowords like viotín (same shape as its base word: violín) vs. viocín (different shape) in mature (college-aged skilled readers), immature (normally reading children), and immature/impaired (young readers with developmental dyslexia) word-recognition systems. Results revealed similar response times (and error rates) to consistent-shape and inconsistent-shape pseudowords for both adult skilled readers and normally reading children – this is consistent with current models of visual-word recognition. In contrast, young readers with developmental dyslexia made significantly more errors to viotín-like pseudowords than to viocín-like pseudowords. Thus, unlike normally reading children, young readers with developmental dyslexia are sensitive to a word’s visual cues, presumably because of poor letter representations.


1974 ◽  
Vol 19 (2) ◽  
pp. 102-103
Author(s):  
CARL GERBER
Keyword(s):  

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