Intraoperative localization and preservation of reading in ventral occipitotemporal cortex

Resective surgery in language-dominant ventral occipitotemporal cortex (vOTC) carries the risk of causing impairment to reading. As it is not on the lateral surface, it is not easily accessible for intraoperative mapping and extensive stimulation mapping can be time consuming. Here we assess the feasibility of using task-based electrocorticography (ECoG) recordings intraoperatively to help guide stimulation mapping of reading in vOTC. In 11 patients undergoing extraoperative, intracranial seizure mapping we recorded induced broadband gamma activation (70 - 150 Hz) during a visual category localizer. Word-responsive cortex localized in this manner showed a high sensitivity (72%) to stimulation-induced reading deficits, and the confluence of ECoG and stimulation positive sites appears to demarcate the visual word form area. In two additional patients, with pathologies necessitating resections in language-dominant vOTC, task-based functional mapping was performed intraoperatively using subdural ECoG, alongside direct cortical stimulation. Cortical areas critical for reading were mapped and successfully preserved, while enabling pathological tissue to be completely removed. Data collection is possible in <3 minutes and initial intraoperative data analysis takes <3 minutes, allowing for rapid assessment of broad areas of cortex. Eloquent cortex in ventral visual cortex can be rapidly mapped intraoperatively using ECoG. This method acts to guide high-probability targets for stimulation, with limited patient participation, and can be used to avoid iatrogenic dyslexia following surgery.

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The Visual Word Form Area natively processes shape sequences: Implications for developmental dyslexia

10.31234/osf.io/vr58g ◽

2019 ◽

Author(s):

Carol Whitney ◽

Paddy Ross ◽

Zhiheng Zhou ◽

Lars Strother

Keyword(s):

Word Recognition ◽

Developmental Dyslexia ◽

Recognition System ◽

Visual Word ◽

Cortical Region ◽

Word Form ◽

Phonological Decoding ◽

Visual Word Form Area ◽

Occipitotemporal Cortex ◽

Whole Word

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.

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A novel hypothesis for the original functionality of the Visual Word Form Area: Processing shape sequences

10.31234/osf.io/g3n2m ◽

2019 ◽

Author(s):

Carol Whitney ◽

Paddy Ross ◽

Zhiheng Zhou ◽

Lars Strother

Keyword(s):

Visual Word ◽

Cortical Region ◽

Word Form ◽

Visual Word Form Area ◽

Action Analysis ◽

Sequential Activation ◽

Occipitotemporal Cortex ◽

Fmri Analysis ◽

Biological Shape ◽

New Hypothesis

There is ongoing debate about what characteristics of left ventral occipitotemporal cortex drive development of the Visual Word Form Area (VWFA). We offer a new hypothesis. A summary of occipitotemporal organization indicates that the VWFA falls in a cortical region supporting action analysis, rather than object recognition. We discuss evidence that letters are serially processed in a top-down manner during the initial years of reading acquisition, and propose that this sequential activation of letter representations causes the VWFA to develop in motion-sensitive cortex specialized for processing of non-biological shape sequences. Supporting this hypothesis, a new fMRI analysis identifies a left-lateralized region that responds more strongly to dynamic motion of objects than humans; this region's location (-48, -55, -8) falls almost exactly at the canonical VWFA coordinates (-45, -57, -12).

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Functionally Separable Font-invariant and Font-sensitive Neural Populations in Occipitotemporal Cortex

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_01408 ◽

2019 ◽

Vol 31 (7) ◽

pp. 1018-1029 ◽

Cited By ~ 2

Author(s):

Zhiheng Zhou ◽

Tutis Vilis ◽

Lars Strother

Keyword(s):

Visual Word ◽

Neural Mechanisms ◽

Word Form ◽

Invariant Representation ◽

Visual Word Form Area ◽

Repetition Suppression ◽

Neural Populations ◽

Occipitotemporal Cortex ◽

Middle Occipital Gyrus ◽

Repeated Words

Reading relies on the rapid visual recognition of words viewed in a wide variety of fonts. We used fMRI to identify neural populations showing reduced fMRI responses to repeated words displayed in different fonts (“font-invariant” repetition suppression). We also identified neural populations showing greater fMRI responses to words repeated in a changing font as compared with words repeated in the same font (“font-sensitive” release from repetition suppression). We observed font-invariant repetition suppression in two anatomically distinct regions of the left occipitotemporal cortex (OT), a “visual word form area” in mid-fusiform cortex, and a more posterior region in the middle occipital gyrus. In contrast, bilateral shape-selective lateral occipital cortex and posterior fusiform showed considerable sensitivity to font changes during the viewing of repeated words. Although the visual word form area and the left middle occipital gyrus showed some evidence of font sensitivity, both regions showed a relatively greater degree of font invariance than font sensitivity. Our results show that the neural mechanisms in the left OT involved in font-invariant word recognition are anatomically distinct from those sensitive to font-related shape changes. We conclude that font-invariant representation of visual word form is instantiated at multiple levels by anatomically distinct neural mechanisms within the left OT.

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Neural Responses of the Anterior Ventral Occipitotemporal Cortex in Developmental Dyslexia: Beyond the Visual Word Form Area

Investigative Opthalmology & Visual Science ◽

10.1167/iovs.18-26325 ◽

2019 ◽

Vol 60 (4) ◽

pp. 1063 ◽

Cited By ~ 1

Author(s):

Ana Pina Rodrigues ◽

José Rebola ◽

Marcelino Pereira ◽

Marieke van Asselen ◽

Miguel Castelo-Branco

Keyword(s):

Developmental Dyslexia ◽

Visual Word ◽

Word Form ◽

Neural Responses ◽

Visual Word Form Area ◽

Occipitotemporal Cortex

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Neurodegeneration of the visual word form area in a patient with word form alexia

Neurology and Clinical Neuroscience ◽

10.1111/ncn3.12516 ◽

2021 ◽

Author(s):

Adithya Chandregowda ◽

Joseph R. Duffy ◽

Mary M. Machulda ◽

Val J. Lowe ◽

Jennifer L. Whitwell ◽

...

Keyword(s):

Visual Word ◽

Word Form ◽

Visual Word Form Area

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A tale of two recognition systems: Implications of the fusiform face area and the visual word form area for lateralized object recognition models

Neuropsychologia ◽

10.1016/j.neuropsychologia.2008.08.024 ◽

2009 ◽

Vol 47 (1) ◽

pp. 1-16 ◽

Cited By ~ 76

Author(s):

Joseph Dien

Keyword(s):

Object Recognition ◽

Visual Word ◽

Word Form ◽

Fusiform Face Area ◽

Visual Word Form Area ◽

Face Area ◽

Recognition Systems

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Spoken language coding neurons in the Visual Word Form Area: Evidence from a TMS adaptation paradigm

NeuroImage ◽

10.1016/j.neuroimage.2018.11.014 ◽

2019 ◽

Vol 186 ◽

pp. 278-285 ◽

Cited By ~ 4

Author(s):

Chotiga Pattamadilok ◽

Samuel Planton ◽

Mireille Bonnard

Keyword(s):

Spoken Language ◽

Visual Word ◽

Word Form ◽

Visual Word Form Area

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Cortical selectivity driven by connectivity: Innate connectivity patterns of the visual word form area

10.1101/712455 ◽

2019 ◽

Cited By ~ 2

Author(s):

Jin Li ◽

David E. Osher ◽

Heather A. Hansen ◽

Zeynep M. Saygin

Keyword(s):

Resting State ◽

Functional Organization ◽

Resting State Fmri ◽

Visual Word ◽

Functional Specialization ◽

Word Form ◽

Visual Word Form Area ◽

Connectivity Patterns ◽

Set Up ◽

Language Network

AbstractWhat determines the functional organization of cortex? One hypothesis is that innate connectivity patterns set up a scaffold upon which functional specialization can later take place. We tested this hypothesis by asking whether the visual word form area (VWFA), an experience-driven region, was already connected to proto language networks in neonates scanned within one week of birth. With resting-state fMRI, we found that neonates showed adult-like functional connectivity, and observed that i) language regions connected more strongly with the putative VWFA than other adjacent ventral visual regions that also show foveal bias, and ii) the VWFA connected more strongly with frontotemporal language regions than with regions adjacent to these language regions. These data suggest that the location of the VWFA is earmarked at birth due to its connectivity with the language network, providing evidence that innate connectivity instructs the later refinement of cortex.

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