Visual Evoked Potentials Research Articles (Page 1)

Introduction Evoked potentials have been suggested as potential biomarkers for predicting neurodevelopment. This study aimed to investigate the relationship between evoked potentials (EP) and neurodevelopmental outcomes in preterm infants. Methods Premature infants admitted to the neonatal intensive care unit of a tertiary referral hospital between March 2020 and March 2023 were included in the study. Among them, only those with EP at a corrected age of 40 weeks were included, meanwhile, infants who did not undergo the test or had abnormal results were excluded. Additionally, patients with follow-up developmental outcomes such as the Hammersmith Infant Neurological Examination (HINE) at 3 months corrected age or the Gross Motor Function Measure (GMFM) at 6 months corrected age were included. Results A total of 24 participants were included in this study. No significant differences in the clinical factors and results of the EP studies were observed between the two groups divided by a HINE score of 60. Hierarchical logistic regression analysis revealed that visual EP was the only factor that correlated with the lying and rolling domains of the GMFM ( P = 0.028). Discussion A significant association was observed between the GMFM and visual EP. Integrating the visual EP latency with other parameters may improve clinical assessments to predict developmental outcomes, possibly improving the accuracy of medical interventions and patient outcomes.

Letter to the editor: comment on "primary visual cortex impairment due to trans-synaptic degeneration after optic neuritis: a systematic review of neuroimaging studies".

Serum neurofilament light chain levels suggest neuroprotection following bexarotene-induced remyelination in people with relapsing remitting multiple sclerosis.

Rationale:Neuromyelitis optica spectrum disorder (NMOSD) is a relapsing-remitting, chronic progressive inflammatory demyelinating disease of the central nervous system, predominantly affecting the optic nerves and spinal cord. Currently, there is no effective cure, and the overall prognosis is poor. Notably, the aquaporin-4 immunoglobulin G (AQP4-IgG) seropositive subtype (historically termed neuromyelitis optica) is associated with a significantly worse prognosis.Patient concerns:Findings included left optic disc edema, prolonged P100 wave latencies and reduced amplitudes on visual evoked potentials (VEP) bilaterally, and concentric constriction of the left visual field. Fundus fluorescein angiography of the left eye revealed hyperfluorescence of the optic nerve. Contrast-enhanced magnetic resonance imaging demonstrated patchy and linear enhancement in the left optic nerve and linear enhancement in the right optic nerve (serum AQP4-IgG positivity confirmed by a tertiary hospital).Diagnoses:The patient has been diagnosed with AQP4-IgG seropositive NMOSD.Interventions:The regimen consisted of intravenous methylprednisolone pulse 1000 mg daily for 5 consecutive days, combined with a single intravenous infusion of inebilizumab (brand name: Uplizna; MedImmune Pharma B.V.; specification: 100 mg/vial) at a dose of 300 mg.Outcomes:At the 1-month follow-up post-treatment, the patient’s left eye visual acuity recovered to 1.0. Fundus examination revealed normal retinal and macular structure bilaterally with resolved optic disc edema. Right eye VEP showed normalized P100 latency and amplitude. Left eye VEP still exhibited prolonged P100 latency and subnormal amplitude. Visual field testing results were normal in both eyes.Lessons:This case demonstrates that combination therapy with IVMP and inebilizumab during the acute phase significantly promoted visual recovery in this AQP4-IgG seropositive NMOSD patient. This finding enhances our understanding of NMOSD management. The case offers valuable clinical insights for therapeutic strategies in NMOSD. Future studies with larger cohorts are warranted to further evaluate the efficacy of the intravenous methylprednisolone pulse–inebilizumab combination in reducing relapse rates and improving long-term neurological outcomes in NMOSD.

Background: Neuromyelitis optica spectrum disorder (NMOSD) causes severe optic nerve (ON) inflammation and vision loss. Current treatments remain limited, prompting exploration of new therapeutic strategies. This study evaluated the efficacy of ITRI-E-(S)4046 (ITRI-ES), a dual ROCK1/2 and MYLK4 kinase inhibitor, in a rat model of NMOSD optic neuritis. Methods: NMOSD-like optic neuritis was induced in rats by applying NMOSD patient serum-soaked sponges around the ON. Rats received intravitreal injections of either 0.2% ITRI-ES, phosphate-buffered saline (PBS), or intraperitoneal methylprednisolone (MP). Visual function was assessed using flash visual-evoked potentials (fVEP). Retinal ganglion cell (RGC) survival and apoptosis were quantified using FluoroGold retrograde labeling and TUNEL assay. ON inflammation and demyelination were evaluated via immunohistochemistry and Western blot analysis of aquaporin-4 (AQP4), myelin basic protein (MBP), glial fibrillary acidic protein (GFAP), and inflammatory markers. Results: ITRI-ES significantly preserved visual function, restoring fVEP amplitudes (~36 μV vs. ~21 μV in PBS-treated, p < 0.05) and RGC density (~85% of normal vs. ~37% PBS). RGC apoptosis was reduced (~2.3-fold lower vs. PBS, p < 0.05). PBS-treated rats showed decreased AQP4 and MBP (2.5–2.8-fold vs. sham) and increased GFAP (2.8-fold). ITRI-ES maintained higher AQP4 (~3.5-fold) and MBP (~1.5-fold) levels, suppressed GFAP (~5.5-fold vs. PBS), reduced NF-κB, IL-1β, TNF-α, microglia activation, and macrophage infiltration, and increased anti-inflammatory Arg1 and CD206 markers (~3-fold vs. PBS). Conclusions: ITRI-ES alleviates optic nerve inflammation, preserves retinal integrity, and maintains visual function in NMOSD-associated optic neuritis, underscoring kinase inhibition as a promising therapeutic strategy.

This review analyzes the utility of visual evoked potentials (VEP) as a method for visual function assessment in optic neuropathies. We systematically reviewed the existing data on the application of several types of VEP (pattern-reversal, pattern-onset/offset, flash-pattern, and chromatic) for objective assessment of the visual pathway in inflammatory, demyelinating, ischemic, toxic, compressive and traumatic optic neuropathies. The review presents the typical changes in VEP parameters (latency, amplitude and morphology) for each of the pathologies considered, and their relationships with clinical manifestations and results of other neuroophthalmological examination techniques such as perimetry and optical coherence tomography. The paper highlights the diagnostic and differential diagnostic value of VEP, especially in challenging cases and for providing an objective approach for characterizing visual function deficiencies.

Aims: To evaluate central and peripheral nerve conduction in patients with type 2 diabetes mellitus (T2DM) using visual evoked potentials (VEP) and nerve conduction studies, and to investigate their relationship with diabetes duration and diabetic retinopathy severity. Methods: This retrospective cross-sectional study included 100 T2DM patients and 100 age- and sex-matched healthy controls. P100 latency was measured for central conduction, while distal latency, amplitude, and conduction velocity of the tibial, ulnar, and sural nerves were assessed for peripheral conduction. Statistical analyses included t-tests, Mann–Whitney U tests, Chi-square tests, ANOVA, Kruskal–Wallis tests, and Spearman’s correlations. Results: P100 latency was significantly prolonged in the diabetic group compared with controls (113.07±4.66 ms vs. 104.10±3.25 ms; p

Disturbances in neuroplasticity are associated with many psychiatric and neurological disorders. Noninvasive electroencephalography (EEG) recordings of visually evoked potentials (VEPs) are promising for assessing plasticity in the human visual cortex, which may represent long-term potentiation (LTP). However, the variability in stimulation parameters limits the comparability and identification of optimal plasticity-inducing protocols. In this study, we systematically compared four VEP modulation protocols—low-frequency, repeated low-frequency, high-frequency, and theta-pulse stimulation—and assessed their effects on visual cortical plasticity. We analyzed 152 EEG recordings, where VEPs were evoked via a checkerboard reversal stimulus before and after low-frequency, repeated low-frequency, high-frequency, and theta-pulse stimulation. Changes in VEP amplitudes were measured from baseline to 2–28 min postmodulation. Low-frequency stimulation produced transient changes in plasticity, peaking at 2 min but dissipating within 12 min. Repeated low-frequency stimulation induced more sustained changes in plasticity, persisting for up to 22 min. High-frequency stimulation induced sharp but brief increases in plasticity indices, whereas theta-pulse stimulation was associated with moderate but prolonged changes in plasticity, lasting up to 28 min. These findings highlight the crucial influence of stimulation parameters on short- and long-term synaptic plasticity indices. Depending on the objective, a suitable induction protocol can be selected to optimize the desired effects, such as increasing sensitivity to drug effects or targeting longer-lasting plasticity outcomes. Optimized VEP paradigms have strong translational potential for assessing neuroplasticity deficits in individuals with psychiatric and neurodegenerative disorders, paving the way for the development of new biomarkers and therapeutic strategies.

Background: Atogepant is a novel oral preventive migraine treatment acting as a calcitonin gene-related peptide (CGRP) receptor antagonist. Our study aims to investigate the impact of a 3-monht course of atogepant treatment on neurophysiological markers of central sensitization and habituation. Methods: This is a prospective study enrolling subjects with high-frequency episodic migraine (HFEM) presenting 8-14 monthly migraine days (MMDs). Neurophysiological assessments were performed during the inter-ictal phase according to standardized protocols. These included evaluation of the nociceptive withdrawal reflex (single stimulus threshold – RTh, and temporal summation threshold – TST) of the lower limb, the nociceptive blink reflex (nBR), and visual evoked potentials (VEPs). Participants were assessed at baseline (T0) and after three months of daily atogepant 60 mg intake (T1). Responders achieved a reduction of at least 50% in monthly migraine days at T1. Results: We enrolled 22 subjects with HFEM (37.7 ± 11.8 years, 16 females). At baseline they presented a mean of 10.2 ± 2.0 MMDs associated with a high migraine-related disability (MIDAS T0: 45.4 ± 29.4). Atogepant determined a reduction in MMDs and MIDAS score (MMDs T1 4.8 ± 3.7, p<0.001 vs. T0, MIDAS T1 8.6 ± 10.4, p<0.001 vs. T0). Responder rate at T1 was 68.2% (15/22). At T1 we found an increase in the RIII reflex threshold (T0: 13.3 ± 5.7 vs. T1: 15.8 ± 6.7, p<0.001), but not in the TST (T0: 9.3 ± 4.6 vs. T1: 10.3 ± 4.6, p<0.389). nRB assessed at 0.2Hz, 0.3Hz and 0.5Hz showed a baseline habituation, confirmed at T1 (Factor BLOCK p<0.001 for all comparisons). At 0.2Hz we observed a reduction in the area of the first block at T1 (T0: 1.48±0.9 μVxms p<0.001 vs. T1: 1.0 ± 0.5μVxms, p=0.050). PEV evaluation showed a lack of habituation both at T0 and T1 (habituation index – HI T0: 92.2 ± 22.1 vs. T1 93.2 ± 13.1, p=0.794). Conclusion: Our findings suggest that atogepant treatment induces an improvement in central sensitization mechanisms and a modulation of the habituation pattern. Further studies are needed to assess whether the observed results are a direct atogepant effect or a compensatory mechanism related to clinical improvement.

Visual impairments pose a significant global health challenge, and visual electrophysiological (EP) acquisition plays a pivotal role in diagnosing ophthalmic diseases. However, traditional electrodes still encounter limitations such as inadequate mechanical adaptability and reusability. This study proposes a stretchable and transparent electrode (STE) consisting of a conductive paste/indium tin oxide layer on a polymethyl methacrylate substrate. Leveraging an island–bridge design, the STE renders reliable performance even after being subjected to 1000 cycles of 25% lateral strain and 18% diagonal strain, exhibiting exceptional mechanical flexibility and realizing seamless attachment to soft tissue. Furthermore, optimized conductive paste layer thickness yields a signal-to-noise ratio comparable to commercial electrodes, achieving equivalent performance to Ag/AgCl electrodes in electroretinogram (ERG), electrooculography (EOG), and visual evoked potential (VEP) acquisition. The STE’s mechanical suitability and inconspicuous features hold significant potential for widespread clinical adoption in ophthalmic diagnostics and personalized eye healthcare, offering improved comfort, reusability, and diagnostic precision.

Studying the effect of the development of the sensorimotor system on the adaptive and compensatory mechanisms of the brain under the influence of various environmental factors, primarily physical ones, is a pressing task for psycho- and neurophysiology. The purpose of this paper was to investigate the dependence of the parameters of flash visual evoked potentials (VEP) on the psychophysiological characteristics of healthy 18–20-year-old individuals. Materials and methods. The research was conducted at the Normal Physiology Department, N.N. Burdenko Voronezh State Medical University. It involved 19 apparently healthy male and female students aged between 18 and 20 years, all of them right-handed. The following parameters were determined: body weight and height, visual acuity according to the Sivtsev table, pupillary reflex, state and trait anxiety according to Spielberger, level of happiness on a 10-point scale, average time spent on the computer (phone) per day, and well-being, activity and mood (according to a questionnaire). Flash VEP were recorded in standard conditions (in a resting state while sitting with eyes closed) using the Neuromyan NMA-4-01 neuromyoanalyser. The relationships between psychophysiological parameters and flash VEP amplitude and duration were studied. Results. We confirmed data (Zelentsov R.N., Poskotinova L.V., 2020) on the correlation between flash VEP parameters and age and on the lack of correlation between flash VEP parameters and visual acuity in healthy adults. It was demonstrated that increasing the time spent on interaction with gadgets synchronizes the work of brain stem neurons. The psychological state of a person affects not only the synchronization of neurons in Brodmann area 17, but also all levels of VEP generalization, and is a reflection of the intensity of information processing. It was observed that the temporal parameters of VEP, in effect, demonstrate the conditions in which the visual system operates and indicate the state of the structures that provide vision, while the amplitude parameters of VEP are linked with a person’s psychophysiological state.

The central nervous system is characterized by its limited regenerative potential, yet striking examples of functional recovery after injury in animal models and humans highlight its capacity for repair. Little is known about repair of pathways/circuits after traumatic brain injury (TBI), which results in disruption of connectivity. Here we utilize a mouse model of diffuse traumatic axonal injury (Impact-acceleration TBI) in order to explore, for the first time, the evolution of structural and functional changes in the terminal fields of the injured visual system. Retinal ganglion cell (RGC) axons and synapses were genetically labeled via AAV transduction, while anterograde and transsynaptic tracers were used to mark terminals and postsynaptic cells. Functional connectivity and visual integrity were assessed by monitoring c-Fos expression following light stimulation and pattern-reversal visual evoked potentials (pVEPs). Our findings demonstrate that, although TAI results in approximately a 50% loss of RGC axons and terminals, surviving RGCs undergo collateral sprouting, a form of compensatory branching of surviving axons, that restores terminal density to pre-injury levels. Transsynaptic tracing and c-Fos mapping confirmed the reestablishment of connectivity, which was also associated with significant improvements in visual function as measured by pVEPs. Interestingly, the recovery process exhibited sexual dimorphism, with female mice showing delayed or incomplete repair. Moreover, collateral sprouting proceeded normally in Sarm1 knockout mice, evidence of some independence from Wallerian degeneration. Our findings show that collateral sprouting may be an important mechanism of circuit repair in TAI and may represent a promising target for therapeutic interventions.

Sex differences in attentional visual processing but not in plasticity-related modulation of visually evoked potentials.

Effects of topical coenzyme Q10 in conjunction with vitamin e on the pattern visual evoked potential, visual field, retinal ganglion cell layer and retinal nerve fibre layer thickness in patients with primary open-angle glaucoma.

Cell-based therapies, particularly transplanted human oligodendrocyte progenitor cells (OPCs), are being explored for neuroprotection and remyelination in demyelinating diseases of the central nervous system (CNS). In this study, we investigated the potential of OPC transplantation into the optic nerve of dark agouti (DA) rats with experimental autoimmune encephalomyelitis (EAE). Human OPCs were transplanted 30 days after EAE induction in one optic nerve, while the contralateral nerve was injected with a vehicle. FTY720 (fingolimod) was administered starting from day 25 post-EAE to prevent graft rejection. Rats were monitored clinically and electrophysiologically using visually evoked potentials (VEPs) for up to 90 days post-transplant. Histological analysis of OPC viability, myelin, and axonal integrity was performed on days 30, 60, and 90 post-transplant. At days 30 and 60, sparse OPCs were detected in the injected optic nerve. However, no live cells were detected on day 90. There were no significant differences in myelin or axonal integrity between the OPC- and vehicle-injected nerves. The VEP traces were severely distorted throughout the 90-day follow-up. This approach did not show long-term viability following direct injection of OPCs in the optic nerve of EAE rats. Challenges related to graft rejection and cell transplantation are discussed, with implications for future research in cell-based therapies.

The use of optical coherence tomography and visual evoked potentials in the 2024 McDonald diagnostic criteria for multiple sclerosis.

Encapsulated mesenchymal stem cell-derived exosomes promote optic nerve regeneration and functional recovery in a mouse model of optic nerve crush injury.

BackgroundMultiple sclerosis (MS) is a chronic demyelinating disease with a heterogeneous clinical course, making long-term disability prediction challenging. Visual evoked potentials (VEPs), particularly amplitude-based parameters, may serve as sensitive biomarkers of neurodegeneration and functional decline undetected by conventional clinical measures.ObjectiveTo assess the relationship between longitudinal changes in P100–N145 amplitude and concurrent Expanded Disability Status Scale (EDSS) changes in relapsing–remitting MS (RRMS) and the relative utility of baseline and longitudinal VEP parameters in representing disability status.MethodsIn this retrospective cohort study, 45 MS patients (90 eyes) with available VEP and EDSS data were followed for a median period of 48 months. The primary endpoints were (1) change in EDSS score over time and (2) EDSS progression, defined as any increase in EDSS score from baseline to follow-up. Generalized estimating equations (GEE) and logistic regression were used to investigate the relationships between the VEP parameters at baseline and follow-up and EDSS progression, accounting for inter-eye correlation; partial correlation analysis assessed amplitude–EDSS change associations, controlling for age.ResultsEDSS progression was observed in 17.8% of patients. A longitudinal decrease in P100–N145 amplitude from baseline to follow-up was significantly associated with EDSS progression (OR: 1.511, 95% CI, p < 0.001). In addition, partial correlation analysis adjusting for age revealed a significant negative association between the difference in P100–N145 amplitude and EDSS difference (defined as baseline minus follow-up) in both eyes (right eye: r = −0.339, p = 0.024; left eye: r = −0.406, p = 0.006). In contrast, the changes in P100 latency and N75–P100 amplitude did not correlate significantly with EDSS worsening. Baseline VEP parameters, including P100 latency, N75–P100, and P100–N145 amplitudes, did not predict EDSS progression or change over time (all p > 0.05).ConclusionOur results demonstrate that a reduction in P100–N145 amplitude over time is associated with worsening disability in RRMS. This suggests that the P100–N145 may be an underestimated marker of progressive functional deterioration in RRMS.

Visual evoked potentials (VEPs) recorded by encephalography (EEG) allow us to study the neuronal activity non-invasively and in high temporal resolution. Traditionally, EEG analyses have relied on univariate group-level statistics and trial averaging to detect effects. However, recent advances in high-density EEG enable the investigation of brain responses at the single-subject and single-trial level. In this study, we combine ultra-high-density (uHD) EEG with cross-validated single-trial decoding to bridge both approaches, improving generalizability and reproducibility. Study participants were shown a diverse set of random images while 512 channels from the uHD system recorded their EEG over the occipital lobe. Image properties (contrast, hue, luminance, saturation and spatial frequency) were extracted for each stimuli and VEPs were used for decoding these properties in a cross-validated regression analysis. Additionally, the same data were spatially subsampled to investigate the impact of spatial resolution and electrode density on the decoding performance. Image properties could be decoded from single-trial VEPs, with contrast, saturation and spatial frequency providing the best decoding performances. Grand average decoding performance across all image properties and subjects yielded a Pearson’s r of 0.50 between predicted and actual image property score. Greater electrode density improves decoding performance compared to standard EEG as well as subsampled configurations. Image properties robustly modulate early components of the VEP. Importantly, these modulations are pronounced enough to allow for single-trial decoding. Our analyses highlight the importance of electrode density with improvements in decoding performance extending even below 10 mm of inter-electrode distance.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-18275-5.

Background and ObjectivesAcute demyelinating optic neuritis (AON) can lead to irreversible neuroaxonal loss. We investigated the neuroprotective effects of phenytoin on macular ganglion cell-inner plexiform layer (mGCIPL) thickness.MethodsWe reanalyzed Spectralis optical coherence tomography scans from the phenytoin AON trial (NCT01451593), a randomized, placebo-controlled, double-blind phase 2 trial. Participants attended 2 trial centers in London or Sheffield, United Kingdom. Patients with unilateral AON, age 18–60 years, within 2 weeks of onset, with visual acuities 6/9 or worse, were randomly assigned (1:1) to oral phenytoin (4–6 mg/kg/d) or placebo for 3 months, stratified by onset time, center, previous multiple sclerosis diagnosis, disease-modifying treatment, and corticosteroid use. Macular ganglion cell-inner plexiform layer thicknesses were extracted at baseline and 6 months. Linear regression models evaluated treatment effects on 6-month affected eye mGCIPL, adjusting for 6-month full-field visual evoked potential (VEP) latency and amplitude and baseline variables including mGCIPL thicknesses, steroid use, baseline acuity, and time interval to treatment. We also compared neuroprotective effects between peripapillary retinal nerve fiber layer (pRNFL) and mGCIPL outcomes.ResultsEighty patients (39 phenytoin: 41 placebo) with a mean age of 33.59 years, 70% female, participated in this study. At 6 months, significant treatment effects were estimated for phenytoin vs placebo (affected eye mGCIPL thicker by 6.79 μm, p = 0.006, [SE = 2.35 µm]); estimated means for mGCIPL thickness for phenytoin vs placebo were 73.8 μm (SE = 2.40 μm) and 67.0 μm (SE = 2.2 μm), respectively. Treatment effects appeared to be greater for worse baseline acuities. At 6 months, higher mGCIPL thicknesses were associated with lower VEP latencies (p < 0.0001) and higher VEP amplitudes (p = 0.013). Neuroprotective effects on mGCIPL outcomes were more robust than for pRNFL outcomes.DiscussionThis study supports superiority of the mGCIPL over the pRNFL as a neuroprotective marker after AON and demonstrates strong associations with myelination, providing additional mechanistic insights.Trial Registration InformationThis trial is registered with ClinicalTrials.gov, number NCT01451593; submitted for registration on October 11, 2011; first patient enrollment was on February 2, 2012.Classification of EvidenceThis study provides Class II evidence that compared with placebo, phenytoin is associated with greater preservation of the mGCIPL thickness in patients with acute demyelinating optic neuropathy.