Response variability to high rates of electric stimulation in retinal ganglion cells

Cai, Changsi; Ren, Qiushi; Desai, N. J.; Rizzo, Joseph F.; Fried, Shelley I.

doi:10.1152/jn.00956.2010

Cited by 52 publications

(69 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Stimulation rate has also been shown to influence the color of the percept with epiretinal stimulation (Stanga PE, et al IOVS 2011;52:ARVO E-Abstract 4949; Stanga PE, et al IOVS 2012;53:ARVO E-Abstract 6952). These results suggest that stimulation rate may have affected neuronal selectivity, as different types of RGCs in vitro have been shown to ''follow'' (i.e., produce at least one spike per pulse) at different maximum stimulus rates, [45][46][47][48] with some ON-OFF directionally sensitive RGCs able to follow up to 2000-pps stimuli. 49 Higher rates may have also predominantly stimulated RGCs with less activation of the remaining neural network, or, alternatively, central mechanisms due to integration of multiple stimuli in a short-term window 50 could have led to differences in appearance.…”

Section: Effect Of Stimulus Parameters On Phosphenesmentioning

confidence: 94%

The Appearance of Phosphenes Elicited Using a Suprachoroidal Retinal Prosthesis

Sinclair

Shivdasani

Perera

et al. 2016

Invest. Ophthalmol. Vis. Sci.

View full text Add to dashboard Cite

Citation: Sinclair NC, Shivdasani MN, Perera T, et al.; for the Bionic Vision Australia Consortium. The appearance of phosphenes elicited using a suprachoroidal retinal prosthesis. Invest Ophthalmol Vis Sci. 2016;57:4948-4961. DOI:10.1167/ iovs.15-18991 PURPOSE. Phosphenes are the fundamental building blocks for presenting meaningful visual information to the visually impaired using a bionic eye device. The aim of this study was to characterize the size, shape, and location of phosphenes elicited using a suprachoroidal retinal prosthesis.METHODS. Three patients with profound vision loss due to retinitis pigmentosa were implanted with a suprachoroidal electrode array, which was used to deliver charge-balanced biphasic constant-current pulses at various rates, amplitudes, and durations to produce phosphenes. Tasks assessing phosphene appearance, location, overlap, and the patients' ability to recognize phosphenes were performed using a custom psychophysics setup.RESULTS. Phosphenes were reliably elicited in all three patients, with marked differences in the reported appearances between patients and between electrodes. Phosphene shapes ranged from simple blobs to complex forms with multiple components in both space and time. Phosphene locations within the visual field generally corresponded to the retinotopic position of the stimulating electrodes. Overlap between phosphenes elicited from adjacent electrodes was observed with one patient, which reduced with increasing electrode separation. In a randomized recognition task, two patients correctly identified the electrode being stimulated for 57.2% and 23% of trials, respectively.CONCLUSIONS. Phosphenes of varying complexity were successfully elicited in all three patients, indicating that the suprachoroidal space is an efficacious site for electrically stimulating the retina. The recognition scores obtained with two patients suggest that a suprachoroidal implant can elicit phosphenes containing unique information. This information may be useful when combining phosphenes into more complex and meaningful images that provide functional vision.

show abstract

Section: Effect Of Stimulus Parameters On Phosphenesmentioning

confidence: 94%

The Appearance of Phosphenes Elicited Using a Suprachoroidal Retinal Prosthesis

Sinclair

Shivdasani

Perera

et al. 2016

Invest. Ophthalmol. Vis. Sci.

View full text Add to dashboard Cite

show abstract

“…Several in vitro studies using epiretinal and subretinal stimulation have shown that most types of RGCs are typically ''desensitized'' at high stimulation rates (beyond 200 pps), such that they may fail to ''follow'' each pulse within a high-rate pulse train or produce no spiking at all. [63][64][65] However, there are some types of RGCs that can follow even 600-pps stimulation, 66 and a recent study performing epiretinal stimulation showed robust responses in ON-OFF directionally sensitive RGCs when stimulation was applied at 2000 pps. 67 It is possible that higher rates may provide exclusive activation of RGCs as opposed to the remaining neural network, thus bringing down thresholds and eliciting clearer phosphenes.…”

Section: Stimulus Parameter Influence On Thresholdsmentioning

confidence: 99%

Factors Affecting Perceptual Thresholds in a Suprachoroidal Retinal Prosthesis

Shivdasani

Sinclair

Dimitrov

et al. 2014

Invest. Ophthalmol. Vis. Sci.

112

View full text Add to dashboard Cite

With suprachoroidal stimulation, anodic-first pulses with a monopolar return are most efficacious. To enable high rates, an appropriate combination of pulse width and interphase gap must be chosen to ensure low thresholds and electrode voltages. Electrode-retina distance needs to be monitored carefully owing to its influence on thresholds. These results inform implantable stimulator specifications for a suprachoroidal retinal prosthesis. (ClinicalTrials.gov number, NCT01603576.).

show abstract

“…They therefore resemble the visual input to RGCs during normal vision, wherein periods of fixation are interspersed by saccadic eye movements [11]. The responses evoked by the visual stimuli and, as a result, the temporal patterns of electrical stimulation were sporadic in nature, unlike the regular periodic stimuli more typically used [1]- [4]. Our experimental paradigm therefore more closely approximates the challenge faced by retinal prostheses.…”

Section: Discussionmentioning

confidence: 89%

“…Given that RGCs can fire at high rates (> 200 spikes per second) in response to normal visual stimulation, the ability to evoke high firing rates in RGCs in response to prosthetic stimulation is of direct consequence to the development of functional retinal prostheses. However, reports on the response of RGCs to repetitive stimulation, particularly at high frequencies, have been mixed [1]- [4].…”

Section: Introductionmentioning

confidence: 99%

Efficacy of electrical stimulation of retinal ganglion cells with temporal patterns resembling light-evoked spike trains

Wong

Garrett

Grayden

et al. 2014

2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society

View full text Add to dashboard Cite

People with degenerative retinal diseases such as retinitis pigmentosa lose most of their photoreceptors but retain a significant proportion (~30%) of their retinal ganglion cells (RGCs). Microelectronic retinal prostheses aim to bypass the lost photoreceptors and restore vision by directly stimulating the surviving RGCs. Here we investigate the extent to which electrical stimulation of RGCs can evoke neural spike trains with statistics resembling those of normal visually-evoked responses. Whole-cell patch clamp recordings were made from individual cat RGCs in vitro. We first recorded the responses of each cell to short sequences of visual stimulation. These responses were converted to trains of electrical stimulation that we then presented to the same cell via an epiretinal stimulating electrode. We then quantified the efficacy of the electrical stimuli and the latency of the evoked spikes. In all cases, spikes were evoked with sub-millisecond latency (0.55 ms, median, ON cells, n = 8; 0.75 ms, median, OFF cells, n = 6) and efficacy ranged from 0.4-1.0 (0.79, median, ON cells; 0.97, median, OFF cells). These data demonstrate that meaningful spike trains, resembling normal responses of RGCs to visual stimulation, can be reliably evoked by epiretinal prostheses.

show abstract

Response variability to high rates of electric stimulation in retinal ganglion cells

Abstract: Cai C, Ren Q, Desai NJ, Rizzo JF 3rd, Fried SI. Response variability to high rates of electric stimulation in retinal ganglion cells.

Cited by 52 publications

References 36 publications

The Appearance of Phosphenes Elicited Using a Suprachoroidal Retinal Prosthesis

The Appearance of Phosphenes Elicited Using a Suprachoroidal Retinal Prosthesis

Factors Affecting Perceptual Thresholds in a Suprachoroidal Retinal Prosthesis

Efficacy of electrical stimulation of retinal ganglion cells with temporal patterns resembling light-evoked spike trains

Contact Info

Product

Resources

About