Visual evoked potentials to various check patterns

Röver, J.; Bach, Michael

doi:10.1007/bf00160610

Cited by 10 publications

(8 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Checkerboards (image dimensions are 1024 × 1024 pixels) were radial and consisted of twenty rings, each of which was divided into 18 sectors of interchanging white and black color. This layout compensated for the increase in receptive-field size with eccentricity 30 , 31 . There were four pairs of checkerboard patterns with different proportions of white pixels, corresponding to luminance ratios of 12.5%, 25%, 37.5%, and 50%.…”

Section: Methodsmentioning

confidence: 93%

Increased cross-modal functional connectivity in cochlear implant users

Chen

Puschmann

Debener

2017

Sci Rep

View full text Add to dashboard Cite

Previous studies have reported increased cross-modal auditory and visual cortical activation in cochlear implant (CI) users, suggesting cross-modal reorganization of both visual and auditory cortices in CI users as a consequence of sensory deprivation and restoration. How these processes affect the functional connectivity of the auditory and visual system in CI users is however unknown. We here investigated task-induced intra-modal functional connectivity between hemispheres for both visual and auditory cortices and cross-modal functional connectivity between visual and auditory cortices using functional near infrared spectroscopy in post-lingually deaf CI users and age-matched normal hearing controls. Compared to controls, CI users exhibited decreased intra-modal functional connectivity between hemispheres and increased cross-modal functional connectivity between visual and left auditory cortices for both visual and auditory stimulus processing. Importantly, the difference between cross-modal functional connectivity for visual and for auditory stimuli correlated with speech recognition outcome in CI users. Higher cross-modal connectivity for auditory than for visual stimuli was associated with better speech recognition abilities, pointing to a new pattern of functional reorganization that is related to successful hearing restoration with a CI.

show abstract

Section: Methodsmentioning

confidence: 93%

Increased cross-modal functional connectivity in cochlear implant users

Chen

Puschmann

Debener

2017

Sci Rep

View full text Add to dashboard Cite

show abstract

“…All stimuli (1280 × 1024 pixels) were radial in nature and consisted of 20 rings, each of which was divided into 18 sectors with neighboring sectors being of opposite color. The radial nature of the stimuli compensated for the increase in receptive-field size with eccentricity [ 15 , 16 ]. There were four different pairs of checkerboard patterns that systematically varied in terms of luminance ratio: Level 1 corresponds to 12.5% white pixels, Level 2 corresponds to 25% white pixels, Level 3 corresponds to 37.5% white pixels, and Level 4 corresponds to 50% white pixels.…”

Section: Methodsmentioning

confidence: 99%

Cross-Modal Functional Reorganization of Visual and Auditory Cortex in Adult Cochlear Implant Users Identified with fNIRS

et al. 2016

View full text Add to dashboard Cite

Cochlear implant (CI) users show higher auditory-evoked activations in visual cortex and higher visual-evoked activation in auditory cortex compared to normal hearing (NH) controls, reflecting functional reorganization of both visual and auditory modalities. Visual-evoked activation in auditory cortex is a maladaptive functional reorganization whereas auditory-evoked activation in visual cortex is beneficial for speech recognition in CI users. We investigated their joint influence on CI users' speech recognition, by testing 20 postlingually deafened CI users and 20 NH controls with functional near-infrared spectroscopy (fNIRS). Optodes were placed over occipital and temporal areas to measure visual and auditory responses when presenting visual checkerboard and auditory word stimuli. Higher cross-modal activations were confirmed in both auditory and visual cortex for CI users compared to NH controls, demonstrating that functional reorganization of both auditory and visual cortex can be identified with fNIRS. Additionally, the combined reorganization of auditory and visual cortex was found to be associated with speech recognition performance. Speech performance was good as long as the beneficial auditory-evoked activation in visual cortex was higher than the visual-evoked activation in the auditory cortex. These results indicate the importance of considering cross-modal activations in both visual and auditory cortex for potential clinical outcome estimation.

show abstract

“…All stimuli (1280 Â 1024 pixels) had a radial nature and consisted of 20 rings, each of which was divided into 18 sectors with neighbouring sectors being of opposite phase. The radial nature of the stimuli compensated for the increase in receptive-field size with eccentricity (Zemon and Ratliff, 1982;Rover and Bach, 1985). The luminance for white pixels was 138.6 cd/m 2 and for black pixels 0.25 cd/m 2 (Minolta: LS 110), representing a Michelson contrast of 99.6%.…”

Section: Stimulimentioning

confidence: 99%

Visual activation of auditory cortex reflects maladaptive plasticity in cochlear implant users

Sandmann

Dillier

Eichele

et al. 2012

Brain

199

188

View full text Add to dashboard Cite

Cross-modal reorganization in the auditory cortex has been reported in deaf individuals. However, it is not well understood whether this compensatory reorganization induced by auditory deprivation recedes once the sensation of hearing is partially restored through a cochlear implant. The current study used electroencephalography source localization to examine cross-modal reorganization in the auditory cortex of post-lingually deafened cochlear implant users. We analysed visual-evoked potentials to parametrically modulated reversing chequerboard images between cochlear implant users (n = 11) and normal-hearing listeners (n = 11). The results revealed smaller P100 amplitudes and reduced visual cortex activation in cochlear implant users compared with normal-hearing listeners. At the P100 latency, cochlear implant users also showed activation in the right auditory cortex, which was inversely related to speech recognition ability with the cochlear implant. These results confirm a visual take-over in the auditory cortex of cochlear implant users. Incomplete reversal of this deafness-induced cortical reorganization might limit clinical benefit from a cochlear implant and help explain the high inter-subject variability in auditory speech comprehension.

show abstract

Visual evoked potentials to various check patterns

Cited by 10 publications

References 6 publications

Increased cross-modal functional connectivity in cochlear implant users

Increased cross-modal functional connectivity in cochlear implant users

Cross-Modal Functional Reorganization of Visual and Auditory Cortex in Adult Cochlear Implant Users Identified with fNIRS

Visual activation of auditory cortex reflects maladaptive plasticity in cochlear implant users

Contact Info

Product

Resources

About