Attentional Gating in Primary Visual Cortex: A Physiological Basis for Dyslexia

@article{Vidyasagar2005AttentionalGI,
  title={Attentional Gating in Primary Visual Cortex: A Physiological Basis for Dyslexia},
  author={Trichur Raman Vidyasagar},
  journal={Perception},
  year={2005},
  volume={34},
  pages={903 - 911}
}
The visual magnocellular pathway is known to play a central part in visuospatial attention and in directing attention to specific parts of the visual world in serial search. It is proposed that, in the case of reading, this mechanism is trained to perform a sequential gating of visual information coming into the primary visual cortex to enable further orderly processing by the ventral stream. This scheme, taken together with the potential for plasticity between the different afferent channels… 

Wide and Diffuse Perceptual Modes Characterize Dyslexics in Vision and Audition

It is suggested that the evidence of wide visual and auditory perceptual modes in dyslexics indicates wider multi-dimensional neural tuning of sensory processing interacting with wider spatial attention.

Visual streams and shifting attention.

Visual Attention among Patients with Schizophrenia: A Study of Visual Span and Selectivity in Visual Search

Investigation of visual attention among patients with schizophrenia using the visual search paradigm and eye-tracking methodology indicated that patients’ visual spans are both smaller and/or less dynamic.

Clinical neurophysiology of visual and auditory processing in dyslexia: A review

Attention, reading and dyslexia

The present report points out several problems in the proposed model of magnocellular deficits that cause dyslexia through reduced attention.

The Contribution of the Magnocellular Visual Pathway to the Process of Visual Word Recognition

It is demonstrated that the magnocellular pathway does contribute significantly to the recognition of words and that the parafoveal area of the retina is more heavily dependent on the mag nocellular pathways compared to the foveal Area ofThe retina.

attentional processes predictive of reading in second and third classes the role of selective focused attention and planning

Background: The attentive functions appear to be involved in learning. In particular, at the beginning of schooling the processes of visual attention are important. In subsequent years, in line with
...

References

SHOWING 1-10 OF 98 REFERENCES

Impaired visual search in dyslexia relates to the role of the magnocellular pathway in attention.

The scheme of selective attention proposed from these results provides a neural mechanism that underlies reading and explains the pathophysiology of dyslexia.

From attentional gating in macaque primary visual cortex to dyslexia in humans.

To see but not to read; the magnocellular theory of dyslexia

Attention Modulates Contextual Influences in the Primary Visual Cortex of Alert Monkeys

A neuronal model of attentional spotlight: parietal guiding the temporal

Gating of neuronal responses in macaque primary visual cortex by an attentional spotlight

The results suggest the operation of a feedback in the paradigm that spotlights a topographically restricted area of V1 for further processing at higher levels.

Abnormal processing of visual motion in dyslexia revealed by functional brain imaging

FMRI data reveal differences in the regional functional organization of the cortical visual system in dyslexia, and previous studies have emphasized language deficits.

A physiological correlate of the 'spotlight' of visual attention

A physiological basis for the effects of spatially directed visual attention is identified and retinotopic mapping of attention-related activation was found in primary visual cortex, as well as in dorsomedial and ventral occipital visual areas previously implicated in processing the attended target features.

Neural underpinnings of dyslexia as a disorder of visuo‐spatial attention

A neural theory of how functionally distinct parallel pathways in vision interact with each other in the process of reading is outlined and it is suggested how a defect in these pathways can lead to reading difficulties.
...