Visual temporal processing in dyslexia and the magnocellular deficit theory: the need for speed?

@article{McLean2011VisualTP,
  title={Visual temporal processing in dyslexia and the magnocellular deficit theory: the need for speed?},
  author={Gregor M. T. McLean and Geoffrey William Stuart and Veronika Coltheart and Anne Castles},
  journal={Journal of experimental psychology. Human perception and performance},
  year={2011},
  volume={37 6},
  pages={
          1957-75
        }
}
A controversial question in reading research is whether dyslexia is associated with impairments in the magnocellular system and, if so, how these low-level visual impairments might affect reading acquisition. This study used a novel chromatic flicker perception task to specifically explore temporal aspects of magnocellular functioning in 40 children with dyslexia and 42 age-matched controls (aged 7-11). The relationship between magnocellular temporal resolution and higher-level aspects of… 
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Citation Type

Investigating the role of temporal processing in developmental dyslexia: Evidence for a specific deficit in rapid visual segmentation
TLDR
Evidence is provided for a difference in the fine temporal resolution of visual processing in DD and, considering the growing evidence about a link between visual temporal segregation and neural oscillations at specific frequencies, they support the idea that DD is characterized by an altered oscillatory sampling within the visual system.
Dyslexic children show altered temporal structure of the nonlinear VEP
TLDR
Early cortical mag nocellular processing at low contrast was normal in those with dyslexia, while parvocellar processing was reduced, and the study demonstrated a physiological basis for upper versus lower visual field differences related to magnocellular function.
Visual processing speed as a marker of immaturity in lexical but not sublexical dyslexia
Metacontrast masking as a measure of change detection: Children with poor reading fluency show impaired change detection for both letters and shapes
TLDR
The results indicate that the good readers were able to detect change at higher levels of masking distraction for both the letter and shape targets, indicating that this difference is not specifically related to to the training of graphemic or lexical information but more likely reflects a difference in alerting or pre-recognition stages of visual processing.
Dyslexia: the Role of Vision and Visual Attention
  • J. Stein
  • Biology
    Current Developmental Disorders Reports
  • 2014
Dyslexia is more than just difficulty with translating letters into sounds. Many dyslexics have problems with clearly seeing letters and their order. These difficulties may be caused by abnormal…
Comparison of visual information processing in school-age dyslexics and normal readers via motion-onset visual evoked potentials
Temporal variability predicts the magnitude of between-group attentional blink differences in developmental dyslexia: a meta-analysis
TLDR
A meta-analysis of the between-group main effect (Group Difference) noted in the attentional blink research focused on specific reading impairment suggested that the endogenous engagement of the temporal features of task-set is slower or disrupted in developmental dyslexia.
Temporal sampling in vision and the implications for dyslexia
  • K. Pammer
  • Psychology
    Front. Hum. Neurosci.
  • 2014
TLDR
A common underlying neural mechanism in dyslexia, may subsume qualitatively different manifestations of reading difficulty, which is consistent with the heterogeneity of the disorder, and may open the door for a new generation of exciting research.
Impaired Driving Performance as Evidence of a Magnocellular Deficit in Dyslexia and Visual Stress.
TLDR
Results from this study suggest that a magnocellular deficit offers a likely explanation for individuals who report high symptomology across both conditions and provide a platform for the development of future research, utilizing a clinical population and on-road driving assessment techniques.
Are auditory and visual processing deficits related to developmental dyslexia?
TLDR
Both orthographic processing and rapid automatized naming deficits were associated with dyslexia in the authors' sample, but it is less clear that they was associated with visual processing deficits.
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References

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TLDR
The results suggest that a basic perceptual impairment in dyslexics may be their limited ability to retain-and-compare perceptual traces across brief intervals.
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TLDR
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TLDR
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TLDR
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