ABSTRACT
OBJECTIVES: To observe the clinical efficacy of Tiaoqi Tongjing Mingmu acupuncture (acupuncture for regulating qi, unblocking meridians and brightening eyes) combined with conventional treatment for anisometropic amblyopia children. METHODS: A total of 76 children with monocular anisometropic amblyopia were randomized into an observation group (38 cases, 2 cases dropped out) and a control group (38 cases). The lens covering therapy was adopted in both groups. The conventional treatment i.e. red flash, grating and visual stimulation was given in the control group, 5 min for one item each time; on the basis of the treatment in the control group, acupuncture was applied at bilateral Jingming (BL 1), Cuanzhu (BL 2), Fengchi (GB 20) and Guangming (GB 37) in the observation group. Both groups were treated once every other day, 3 times a week for 4 weeks. Before and after treatment, the best corrected visual acuity, the latency and amplitude of P100 wave of pattern visual evoked potential (P-VEP), the diopter (spherical equivalent [SE]) were observed, the stereoacuity was measured by Titmus stereoscopic examination, and the clinical efficacy was evaluated in both groups. RESULTS: Compared with those before treatment, the best corrected visual acuity improved (P<0.05), the latency of P-VEP P100 wave was shortened and the amplitude of P-VEP P100 wave was increased (P<0.05), and the SE and Titmus values were decreased (P<0.05) after treatment in both groups. After treatment, in the observation group, the best corrected visual acuity was higher (P<0.05), the latency of P-VEP P100 wave was shorter and the amplitude of P-VEP P100 wave was higher (P<0.05), SE and Titmus values were lower (P<0.05) than those in the control group. The total effective rate was 86.1% (31/36) in the observation group, which was superior to 65.8% (25/38) in the control group (P<0.05). CONCLUSIONS: During the visual plasticity period, Tiaoqi Tongjing Mingmu acupuncture combined with conventional treatment can effectively improve the best corrected vision, diopter and stereoacuity in children with anisometropic amblyopia, and enhance the nerve conduction function from retina to visual cortex. Its effect is superior to that of simple conventional treatment.
Subject(s)
Acupuncture Therapy , Amblyopia , Child , Humans , Amblyopia/therapy , Evoked Potentials, Visual , Vision, Ocular , RetinaABSTRACT
Simultaneous EEG-fMRI is a powerful multimodal technique for imaging the brain, but its use in neurofeedback experiments has been limited by EEG noise caused by the MRI environment. Neurofeedback studies typically require analysis of EEG in real time, but EEG acquired inside the scanner is heavily contaminated with ballistocardiogram (BCG) artifact, a high-amplitude artifact locked to the cardiac cycle. Although techniques for removing BCG artifacts do exist, they are either not suited to real-time, low-latency applications, such as neurofeedback, or have limited efficacy. We propose and validate a new open-source artifact removal software called EEG-LLAMAS (Low Latency Artifact Mitigation Acquisition Software), which adapts and advances existing artifact removal techniques for low-latency experiments. We first used simulations to validate LLAMAS in data with known ground truth. We found that LLAMAS performed better than the best publicly-available real-time BCG removal technique, optimal basis sets (OBS), in terms of its ability to recover EEG waveforms, power spectra, and slow wave phase. To determine whether LLAMAS would be effective in practice, we then used it to conduct real-time EEG-fMRI recordings in healthy adults, using a steady state visual evoked potential (SSVEP) task. We found that LLAMAS was able to recover the SSVEP in real time, and recovered the power spectra collected outside the scanner better than OBS. We also measured the latency of LLAMAS during live recordings, and found that it introduced a lag of less than 50 ms on average. The low latency of LLAMAS, coupled with its improved artifact reduction, can thus be effectively used for EEG-fMRI neurofeedback. A limitation of the method is its use of a reference layer, a piece of EEG equipment which is not commercially available, but can be assembled in-house. This platform enables closed-loop experiments which previously would have been prohibitively difficult, such as those that target short-duration EEG events, and is shared openly with the neuroscience community.
Subject(s)
Camelids, New World , Neurofeedback , Adult , Animals , Humans , Magnetic Resonance Imaging/methods , Electroencephalography/methods , Artifacts , Evoked Potentials, VisualABSTRACT
Objective.Evoked potentials (EP), measured using electroencephalographic (EEG) recordings provide an opportunity to monitor cognitive dysfunctions after neurological diseases or traumatic brain injury (TBI). The 4 week old piglet is an established model of paediatric TBI; therefore, healthy piglets were studied to establish feasibility of obtaining responses to auditory and visual stimuli. A secondary aim was to input the EEG data into a piglet computational model to localize the brain sources related to processing. We tested the hypotheses: (1) visual, auditory-standard, and auditory-target stimuli elicit responses, (2) there is an effect of stimulus type, day tested, and electrode region on EPs from EEG, (3) there is an effect of stimulus type, day tested, and brain region on localized sources from a computational model.Approach.Eleven 4 week old female piglets were fitted with a 32-electrode net and presented with a simple white light stimulus and an auditory oddball click train (70 standard; 30 target tones).Main results.N1 andP2 amplitudes were consistently observed for all stimulus types. Significant interaction effects between brain region and stimulus for EP and current density demonstrate that cognitive responses are specific to each modality with auditory localizing to the temporal region and visual to the occipital regions. There was a day effect where larger responses were found on the first day than day 2 and 3 and may be due to the novelty of the stimulus on the first day. Visual stimuli had largerP1 amplitudes and earlier latencies (P1,N1) than auditory which coincides with current density results at 50 ms where larger activations were observed for visual. At 85 ms, auditory had significantly larger current densities coincident with larger and longerN1 amplitudes and latencies than visual.Significance.Auditory and visual processing were successfully and consistently obtained in a porcine model and can be evaluated as a diagnostic assessment for TBI.
Subject(s)
Evoked Potentials, Auditory , Evoked Potentials, Visual , Animals , Female , Swine , Evoked Potentials, Auditory/physiology , Acoustic Stimulation/methods , Evoked Potentials , Electroencephalography/methodsABSTRACT
Attention can be directed externally toward sensory information or internally toward self-generated information. Using electroencephalography (EEG), we investigated the attentional processes underlying the formation and encoding of self-generated mental images into episodic memory. Participants viewed flickering words referring to common objects and were tasked with forming visual mental images of the objects and rating their vividness. Subsequent memory for the presented object words was assessed using an old-new recognition task. Internally-directed attention during image generation was indexed as a reduction in steady-state visual evoked potentials (SSVEPs), oscillatory EEG responses at the frequency of a flickering stimulus. The results yielded 3 main findings. First, SSVEP power driven by the flickering word stimuli decreased as subjects directed attention internally to form the corresponding mental image. Second, SSVEP power returned to pre-imagery baseline more slowly for low- than high-vividness later remembered items, suggesting that longer internally-directed attention is required to generate subsequently remembered low-vividness images. Finally, the event-related-potential difference due to memory was more sustained for subsequently remembered low- versus high-vividness items, suggesting that additional conceptual processing may have been needed to remember the low-vividness visual images. Taken together, the results clarify the neural mechanisms supporting the encoding of self-generated information.
Subject(s)
Evoked Potentials, Visual , Memory, Episodic , Humans , Evoked Potentials/physiology , Attention/physiology , Mental Recall/physiology , ElectroencephalographyABSTRACT
Biases in attention to emotional stimuli (i.e., affect-biased attention) contribute to the development and mainte-nance of depression and anxiety and may be a promising target for intervention. Past attempts to therapeutically modify affect-biased attention have been unsatisfactory due to issues with reliability and precision. Electroencephalogram (EEG)-derived steady-state visual evoked potentials (SSVEPS) provide a temporally-sensitive biological index of attention to competing visual stimuli at the level of neuronal populations in the visual cortex. SSVEPS can potentially be used to quantify whether affective distractors vs. task-relevant stimuli have "won" the competition for attention at a trial-by-trial level during neuro-feedback sessions. This study piloted a protocol for a SSVEP-based neurofeedback training to modify affect-biased attention using a portable augmented-reality (AR) EEG interface. During neurofeedback sessions with five healthy participants, signifi-cantly greater attention was given to the task-relevant stimulus (a Gabor patch) than to affective distractors (negative emotional expressions) across SSVEP indices (p<0.000l). SSVEP indices exhibited excellent internal consistency as evidenced by a maximum Guttman split-half coefficient of 0.97 when comparing even to odd trials. Further testing is required, but findings suggest several SSVEP neurofeedback calculation methods most deserving of additional investigation and support ongoing efforts to develop and implement a SSVEP-guided AR-based neurofeedback training to modify affect-biased attention in adolescent girls at high risk for depression.
Subject(s)
Attentional Bias , Augmented Reality , Neurofeedback , Adolescent , Evoked Potentials, Visual , Female , Humans , Reproducibility of ResultsABSTRACT
Sensory sensitivity symptoms are common in autism spectrum disorders and fragile X syndrome. Mainly in the auditory modality, disturbed processing has been found in both fragile X patients and the corresponding genetic mouse model, the Fmr1 knockout mouse. Here, we tried to replicate the auditory deficits and assess whether also visual processing is affected, using electroencephalography readouts under freely behaving conditions in the second-generation Fmr1 knockout mice. No differences between wild-type and knockout animals were found in single auditory and visual evoked potentials in response to pure sine tones and full-field light flashes. Visual sensory gating was enhanced in the early but not the late components of the evoked potentials, but no changes were found in auditory sensory gating. The higher harmonics of the synchronisation response to flickering visual stimuli seemed to be reduced with 10, but not 20 or 40 Hz, stimulation. However, this effect was not reproduced in an independent second cohort of animals. No synchronisation differences were found in response to a chirp stimulus, of which the frequency steadily increased. Taken together, this study could not reproduce earlier reported increased amplitudes in auditory responses, nor could it convincingly show that synchronisation deficits found to be present in the auditory modality also existed in the visual modality. The discrepancies within this study as well as between various studies assessing sensory processing in the Fmr1 KO raise questions about the external validity of these phenotypes and warrant careful interpretation of these phenotypes.
Subject(s)
Evoked Potentials , Fragile X Mental Retardation Protein , Fragile X Syndrome , Acoustic Stimulation , Animals , Electroencephalography , Evoked Potentials, Auditory , Evoked Potentials, Visual , Fragile X Mental Retardation Protein/genetics , Fragile X Syndrome/genetics , Mice , Mice, Knockout , Phenotype , Visual PerceptionABSTRACT
The hybrid brain-computer interface (hBCI) combining motor imagery (MI) and steady-state visual evoked potential (SSVEP) has been proven to have better performance than a pure MI- or SSVEP-based brain-computer interface (BCI). In most studies on hBCIs, subjects have been required to focus their attention on flickering light-emitting diodes (LEDs) or blocks while imagining body movements. However, these two classical tasks performed concurrently have a poor correlation. Therefore, it is necessary to reduce the task complexity of such a system and improve its user-friendliness. Aiming to achieve this goal, this study proposes a novel hybrid BCI that combines MI and intermodulation SSVEPs. In the proposed system, images of both hands flicker at the same frequency (i.e., 30 Hz) but at different grasp frequencies (i.e., 1 Hz for the left hand, and 1.5 Hz for the right hand), resulting in different intermodulation frequencies for encoding targets. Additionally, movement observation for subjects can help to perform the MI task better. In this study, two types of brain signals are classified independently and then fused by a scoring mechanism based on the probability distribution of relevant parameters. The online verification results showed that the average accuracies of 12 healthy subjects and 11 stroke patients were 92.40 ± 7.45% and 73.07 ± 9.07%, respectively. The average accuracies of 10 healthy subjects in the MI, SSVEP, and hybrid tasks were 84.00 ± 12.81%, 80.75 ± 8.08%, and 89.00 ± 9.94%, respectively. The high recognition accuracy verifies the feasibility and robustness of the proposed system. This study provides a novel and natural paradigm for a hybrid BCI based on MI and SSVEP.
Subject(s)
Brain-Computer Interfaces , Evoked Potentials, Visual , Attention , Brain/physiology , Electroencephalography/methods , Humans , Movement/physiology , Photic Stimulation/methodsABSTRACT
BACKGROUND: Many aspects of steady-state responses of the brain remain unclear in bipolar disorder (BD) due to the small number of auditory steady-state response (ASSR) studies and the lack of steady-state visual evoked potential (SSVEP) studies on this complex disorder. Therefore, we assessed the patterns of SSVEP and ASSR in adolescents with BD during an active task to detect possible deficits in these important brain responses compared to normal subjects. METHODS: 27 adolescents with BD and 30 healthy adolescents were assessed in this study. The blinking background of the monitor presented at 15 Hz and the tone signal stimulation at 40 Hz evoked SSVEPs and ASSRs, respectively. The phase and amplitude of the steady-state responses were calculated in the auditory and visual conditions. RESULTS: Patients exhibited a substantially worse performance in the motor control inhibition task during both auditory and visual modalities. Patients showed increased SSVEP amplitude and phase in the frontal region compared to control adolescents. Also, patients exhibited decreased ASSR amplitude in the prefrontal and increased ASSR amplitude in the right-frontal and centro-parietal areas compared to healthy adolescents. CONCLUSIONS: impairments in the production and preservation of SSVEP and ASSR are evident in BD, implicating abnormalities in visual and auditory pathways. Neurophysiological deficits and worse performance in BD adolescents may imply that visual and auditory pathways cannot well transfer the pertinent information from arriving sensory data to the visual and auditory cortices, and the frontal cortex cannot well integrate incoming signals into a unified and coherent perceptual action.
Subject(s)
Auditory Cortex , Bipolar Disorder , Acoustic Stimulation , Adolescent , Auditory Cortex/physiology , Bipolar Disorder/complications , Electroencephalography , Evoked Potentials, Auditory/physiology , Evoked Potentials, Visual , HumansABSTRACT
Cordyceps cicadae mycelium is an herbal medicine used to provide anti-inflammatory and antiapoptotic actions. However, little is known about the role of C. cicadae mycelium in neuroprotection. This study aimed to investigate the neuroprotective effects of C. cicadae mycelium extract (CCME) in the optic nerve crush (ONC) model. The optic nerves of adult male Wistar rats (aged 7-8 weeks) were crushed by a standardized method. Rats were divided equally into three groups: 1) a sham-operated group (sham), 2) a phosphate buffered saline-treated control group (crush), and 3) a CCME-treated group (CCME) that received CCME once daily for 7 consecutive days at doses of 100 mg/kg before ONC. Two weeks after ONC in rats, retinal ganglion cell (RGC) density and visual function were determined by using retrograde labeling with FluoroGold and flash visual evoked potentials. The terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and immunohistochemistry of ED1 (a marker of macrophage/microglia) were used to evaluate the antiapoptotic and anti-inflammatory effects of CCME in the optic nerve section. The P1-N2 amplitude and RGC density in the CCME-treated group were higher than those in the ONC control (crush) group by 5.15- and 3.13-fold, respectively. The numbers of TUNEL-positive cells and ED1-positive cells in the CCME-treated group were reduced by 4.38- and 6.63-fold, respectively, compared to those in the crush group. Oral administration of CCME provided neuroprotective effects in the ONC model via antiapoptotic and anti-inflammatory actions, which provides a potential treatment for patient with traumatic optic neuropathy.
Subject(s)
Cordyceps , Neuroprotective Agents , Animals , Disease Models, Animal , Evoked Potentials, Visual , Humans , Male , Mycelium , Nerve Crush , Neuroprotective Agents/pharmacology , Optic Nerve , Rats , Rats, WistarABSTRACT
BACKGROUND: Studies have shown that hyperbaric oxygen therapy (HBOT) can improve the extraction rate and latency of cortical evoked potential N20 in patients with severe traumatic brain injury, but there are only a few studies on the effect of flash visual evoked potential. OBJECTIVE: This study investigated the effect of hyperbaric oxygen therapy on the P2 wave of flash visual evoked potentials in patients with severe traumatic brain injury. METHODS: In total, we examined 40 TBI patients who received HBOT, in combination with medication, and 38 TBI patients who received medication alone. The FVEPs apparatus was used to detect the P2 wave extraction rate and the latency of the elicited waveform before and after treatment in both the medicated-only controls and HBOT-treated cohorts. RESULTS: Compared with the control group, the HBOT treatment group showed a higher P2 wave elicitation rate, and the P2 wave latency of the HBOT treatment group was significantly shortened (pâ<â0.05, all). CONCLUSIONS: HBOT, in combination with drug therapy, can significantly increase the P2 wave extraction rate and shorten P2 latency in patients with TBI.
Subject(s)
Brain Injuries, Traumatic , Brain Injuries , Hyperbaric Oxygenation , Brain Injuries/therapy , Brain Injuries, Traumatic/therapy , Evoked Potentials, Visual , Humans , Neurologic ExaminationABSTRACT
A 7 year-old twin girl with hypophosphataemic rickets was evaluated for a recent onset of mild strabismus.She was a homozygous twin sister with hypophosphataemic rickets diagnosed at the age of 2 years, with a mutation in intron 21 of the PHEX gene, which was also present in her sister.The girls' clinical histories were remarkable for an important lower limb varus that progressively improved after starting phosphate supplementation with a galenical solution (Joulies solution 1 mmol phosphate/ml) and vitamin D 1,25 OH.During the examinations, both girls were in good general condition. Physical examinations were unremarkable, except for tibial varus, bilateral fifth finger clinodactyly and bilateral syndactyly of the third and fourth foot fingers. No major head shape abnormalities were noticeable except for a high forehead.One patient presented with a slight strabismus, normal isochoric isocyclic and reactive pupils, no signs of cranial nerve deficit, and no alterations in the rest of the neurological examination. An ophthalmological evaluation showed bilateral papilloedema. A cerebral MRI scan was then performed, suspecting elevated intracranial pressure (figure 1). The same examination was performed on the asymptomatic sister which also demonstrated papilloedema with similar findings on cranial MRI too.
Subject(s)
Familial Hypophosphatemic Rickets , Papilledema , Rickets, Hypophosphatemic , Strabismus , Child , Child, Preschool , Evoked Potentials, Visual , Familial Hypophosphatemic Rickets/diagnosis , Familial Hypophosphatemic Rickets/genetics , Familial Hypophosphatemic Rickets/therapy , Female , Humans , Male , Phosphates , Rickets, Hypophosphatemic/diagnosis , Rickets, Hypophosphatemic/genetics , Rickets, Hypophosphatemic/therapyABSTRACT
Fish oil is rich in omega-3 fatty acids and essential for neuronal myelination and maturation. The aim of this study was to investigate whether the use of a mixed-lipid emulsion composed of soybean oil, medium-chain triglycerides, olive oil, and fish oil (SMOF-LE) compared to a pure soybean oil-based lipid emulsion (S-LE) for parenteral nutrition had an impact on neuronal conduction in preterm infants. This study is a retrospective matched cohort study comparing preterm infants <1000 g who received SMOF-LE in comparison to S-LE for parenteral nutrition. Visual evoked potentials (VEPs) were assessed longitudinally from birth until discharge. The latencies of the evoked peaks N2 and P2 were analyzed. The analysis included 76 infants (SMOF-LE: n = 41 and S-LE: n = 35) with 344 VEP measurements (SMOF-LE: n= 191 and S-LE n = 153). Values of N2 and P2 were not significantly different between the SMOF-LE and S-LE groups. A possible better treatment effect in the SMOF-LE group was seen as a trend toward a shorter latency, indicating faster neural conduction at around term-equivalent age. Prospective trials and follow-up studies are necessary in order to evaluate the potential positive effect of SMOF-LE on neuronal conduction and visual pathway maturation.
Subject(s)
Evoked Potentials, Visual/drug effects , Fat Emulsions, Intravenous/administration & dosage , Fat Emulsions, Intravenous/chemistry , Fish Oils/administration & dosage , Neural Conduction/drug effects , Female , Humans , Infant, Newborn , Infant, Premature/physiology , Male , Olive Oil/administration & dosage , Parenteral Nutrition , Retrospective Studies , Soybean Oil/administration & dosage , Triglycerides/administration & dosageABSTRACT
Stimuli-evoked and spontaneous brain activity propagates across the cortex in diverse spatiotemporal patterns. Despite extensive studies, the relationship between spontaneous and evoked activity is poorly understood. We investigate this relationship by comparing the amplitude, speed, direction, and complexity of propagation trajectories of spontaneous and evoked activity elicited with visual, auditory, and tactile stimuli using mesoscale wide-field imaging in mice. For both spontaneous and evoked activity, the speed and direction of propagation is modulated by the amplitude. However, spontaneous activity has a higher complexity of the propagation trajectories. For low stimulus strengths, evoked activity amplitude and speed is similar to that of spontaneous activity but becomes dissimilar at higher stimulus strengths. These findings are consistent with observations that primary sensory areas receive widespread inputs from other cortical regions, and during rest, the cortex tends to reactivate traces of complex multisensory experiences that might have occurred in exhibition of different behaviors.
Subject(s)
Brain Mapping , Brain Waves , Cerebral Cortex/diagnostic imaging , Evoked Potentials, Auditory , Evoked Potentials, Visual , Voltage-Sensitive Dye Imaging , Acoustic Stimulation , Anesthesia, General , Animals , Cerebral Cortex/physiology , Consciousness , Electric Stimulation , Female , Forelimb/innervation , Hindlimb/innervation , Male , Mice, Inbred C57BL , Mice, Transgenic , Photic Stimulation , Sensory Thresholds , Time Factors , WakefulnessABSTRACT
Functional connectivity networks (FCN) are the physiological basis of brain synchronization to integrating neural activity. They are not rigid but can reorganize under pathological conditions or during mental or behavioral states. However, because mental acts can be very fast, like the blink of an eye, we now used the visual system as a model to explore rapid FCN reorganization and its functional impact in normal, abnormal and post treatment vision. EEG-recordings were time-locked to visual stimulus presentation; graph analysis of neurophysiological oscillations were used to characterize millisecond FCN dynamics in healthy subjects and in patients with optic nerve damage before and after neuromodulation with alternating currents stimulation and were correlated with visual performance. We showed that rapid and transient FCN synchronization patterns in humans can evolve and dissolve in millisecond speed during visual processing. This rapid FCN reorganization is functionally relevant because disruption and recovery after treatment in optic nerve patients correlated with impaired and recovered visual performance, respectively. Because FCN hub and node interactions can evolve and dissolve in millisecond speed to manage spatial and temporal neural synchronization during visual processing and recovery, we propose "Brain Spacetime" as a fundamental principle of the human mind not only in visual cognition but also in vision restoration.
Subject(s)
Brain/physiopathology , Electric Stimulation Therapy/methods , Nerve Net/physiopathology , Optic Nerve Diseases/physiopathology , Optic Nerve Diseases/therapy , Recovery of Function , Visual Perception , Adult , Cognition , Double-Blind Method , Electroencephalography/methods , Electroencephalography Phase Synchronization , Evoked Potentials, Visual , Female , Humans , Male , Middle Aged , Treatment Outcome , Visual Field Tests/methods , Visual FieldsABSTRACT
Complex perceptual decisions, in which information must be integrated across multiple sources of evidence, are ubiquitous but are not well understood. Such decisions rely on sensory processing of each individual source of evidence, and are therefore vulnerable to bias if sensory processing resources are disproportionately allocated among visual inputs. To investigate this, we developed an implicit neurofeedback protocol embedded within a complex decision-making task to bias sensory processing in favor of one source of evidence over another. Human participants of both sexes (N = 30) were asked to report the average motion direction across two fields of oriented moving bars. Bars of different orientations flickered at different frequencies, thus inducing steady-state visual evoked potentials. Unbeknownst to participants, neurofeedback was implemented to implicitly reward attention to a specific "trained" orientation (rather than any particular motion direction). As attentional selectivity for this orientation increased, the motion coherence of both fields of bars increased, making the task easier without altering the relative reliability of the two sources of evidence. Critically, these neurofeedback trials were alternated with "test" trials in which motion coherence was not contingent on attentional selectivity, allowing us to assess the training efficacy. The protocol successfully biased sensory processing, resulting in earlier and stronger encoding of the trained evidence source. In turn, this evidence was weighted more heavily in behavioral and neural representations of the integrated average, although the two sources of evidence were always matched in reliability. These results demonstrate how biases in sensory processing can impact integrative decision-making processes.SIGNIFICANCE STATEMENT Many everyday decisions require active integration of different sources of sensory information, such as deciding when it is safe to cross a road, yet little is known about how the brain prioritizes sensory sources in the service of adaptive behavior, or whether such decisions can be altered through learning. Here we addressed these questions using a novel behavioral protocol that provided observers with real-time feedback of their own brain activity patterns in which sensory processing was implicitly biased toward a subset of the available information. We show that, while such biases are a normal and adaptive mechanism for humans to process complex visual information, they can also contribute to suboptimal decision-making.
Subject(s)
Attention/physiology , Decision Making/physiology , Evoked Potentials, Visual/physiology , Neurofeedback/methods , Perception/physiology , Visual Perception/physiology , Adolescent , Adult , Brain/physiology , Electroencephalography , Female , Humans , Male , Orientation, Spatial/physiology , Reaction Time/physiology , Young AdultABSTRACT
In the past 20 years, neural engineering has made unprecedented progress in the interpretation of brain information (e.g., brain-computer interfaces) and in neuromodulation (e.g., electromagnetic stimulation and neurofeedback). However, there has been little research aiming to improve the performance of brain-computer interfaces (BCIs) using neuromodulation. The present study presents a novel design for a neurofeedback training (NFT) method to improve the operation of a steady-state visual evoked potential (SSVEP)-based BCI and further explores its underlying mechanisms. The use of NFT to upregulate alpha-band power in the user's parietal lobe is presented in this study as a new neuromodulation method to improve SSVEP-based BCI in this study. After users completed this NFT intervention, the signal-to-noise ratio (SNR), accuracy, and information transfer rate (ITR) of the SSVEP-based BCI were increased by 5.8%, 4.7%, and 15.6%, respectively. However, no improvement was observed in the control group in which the subjects did not participate in NFT. Moreover, a general reinforcement of the information flow from the parietal lobe to the occipital lobe was observed. Evidence from a network analysis and an attention test further indicates that NFT improves attention by developing the control capacity of the parietal lobe and then enhances the above SSVEP indicators. Upregulating the amplitude of parietal alpha oscillations using NFT significantly improves the SSVEP-based BCI performance by modulating the control network. The study validates an effective neuromodulation method and possibly contributes to explaining the function of the parietal lobe in the control network.
Subject(s)
Brain-Computer Interfaces , Neurofeedback , Child , Electroencephalography , Evoked Potentials, Visual , Humans , Photic StimulationABSTRACT
OBJECTIVE: To observe the effect of five-element acupuncture on the cognitive function repair of migraine patients with depression/anxiety disorder. METHODS: The migraine patients with depression/anxiety disorder (19 cases, 5 cases dropped off) were taken as the observation group, and received five-element acupuncture twice a week for 8 weeks. Healthy subjects (19 cases) were selected by demographic data matching as the control group. The cognitive function was evaluated with the event related potential (ERP) technique, and the latency and amplitude of visual evoked potential P300 were adopted as the observation indexes. The headache days (every 4 weeks), headache intensity [visual analogue scale(VAS) score], and headache impact test-6 (HIT-6) score, Hamilton depression scale (HAMD) score and Hamilton anxiety scale (HAMA) score were used as the observation indexes for curative effect. RESULTS: Before the treatment, latency of target stimulus at Fz [ (417.5±34.3) ms] in the observation group was extended compared with the healthy subjects of the control group [(388.6±42.1) ms, P<0.05]. In the observation group, the latency of each point target stimulus [Fz: (376.1±36.2) ms, F3: (374.8±37.6) ms, F4: (372.0±37.6) ms] after treatment were shorter than those [Fz: (417.5±34.3) ms, F3: (417.4±33.8) ms, F4: (416.0±36.6) ms] before treatment (P<0.05). Before and after treatment, there was no significant difference in the amplitude of each point between the observation group and the control group (P>0.05). In the observation group, the headache days was shorter than that before treatment (P<0.01), and the VAS score, HIT-6 score, HAMD score and HAMA score were all lower than before treatment (P<0.01). CONCLUSION: There are some cognitive impairments in migraine patients with depression/anxiety disorder. Five-element acupuncture not only relieves headache, anxiety and depression effectively, but also improves the activation level of the frontal lobe. It significantly repairs the impaired cognitive function.
Subject(s)
Acupuncture Therapy , Migraine Disorders , Acupuncture Points , Anxiety Disorders , Cognition , Depression/therapy , Evoked Potentials, Visual , Humans , Migraine Disorders/therapy , Treatment OutcomeABSTRACT
ABSTRACT Purpose: To determine visual impairment due to optic pathway tumors in children unable to perform recognition acuity tests. Methods: Grating visual acuity scores, in logMAR, were obtained by sweep visually evoked potentials (SVEP) in children with optic pathway tumors. The binocular grating visual acuity deficit was calculated by comparison with age-based norms and then assigned to categories of visual impairment as mild (from 0.10 to 0.39 logMAR), moderate (from 0.40 to 0.79 logMAR), or severe (≥0.80 logMAR). Interocular differences were calculated by subtraction and considered increased if >0.10 logMAR. Results: The participants were 25 children (13 boys; mean ± SD age, 35.1 ± 25.9 months; median age, 32.0 months) with optic pathway tumors (24 gliomas and 1 embryonal tumor), mostly located at the hypothalamic-chiasmatic transition (n=21; 84.0%) with visual abnormalities reported by parents (n=17; 68.0%). The mean grating acuity deficit was 0.60 ± 0.36 logMAR (median, 0.56 logMAR). Visual impairment was detected in all cases and was classified as mild in 10 (40.0%), moderate in 8 (32.0%), and severe in 7 (28.0%) children, along with increased interocular differences (>0.1 logMAR) (n=16; 64.0%). The remarkable ophthalmological abnormalities were nystagmus (n=17; 68.0%), optic disc cupping and/or pallor (n=13; 52.0%), strabismus (n=12; 48.0%), and poor visual behavior (n=9; 36.0%). Conclusion: In children with optic pathway tumors who were unable to perform recognition acuity tests, it was possible to quantify visual impairment by sweep-visually evoked potentials and to evaluate interocular differences in acuity. The severity of age-based grating visual acuity deficit and interocular differences was in accordance with ophthalmological abnormalities and neuroimaging results. Grating visual acuity deficit is useful for characterizing visual status in children with optic pathway tumors and for supporting neuro-oncologic management.(AU)
RESUMO Objetivo: Determinar o grau de deficiência visual em crianças com tumores da via óptica incapazes de informar a acuidade visual de reconhecimento. Método: A acuidade visual de grades, em logMAR, foi estimada por potenciais visuais evocados de varredura em crianças com tumores das vias ópticas. O déficit da acuidade visual de grades binocular foi calculado em relação ao valor mediano normativo esperado para a idade e a deficiência visual, classificada como leve (0,10 a 0,39 logMAR), moderada (0,40 a 0,79 logMAR) ou grave (≥0,80 logMAR). Diferenças inter-oculares foram calculadas por subtração e consideradas aumentadas se >0,10 logMAR. Resultados: Foram avaliadas 25 crianças (13 meninos; média de idade ± DP=35,1± 25,9 meses; mediana=32,0 meses) com tumores da via óptica (24 gliomas e 1 tumor embrionário) localizados particularmente na transição hipotalâmico-quiasmática (n=21; 84,0%) e com anormalidades visuais detectadas pelos pais (n=17; 68,0%). A média do déficit da acuidade de grades foi 0,60 ± 0,36 logMAR (mediana=0,56 logMAR). Observou-se deficiência visual leve em 10 (40,0%), moderada em 8 (32,0%) e grave em 7 (28,0%), além de aumento da diferença interocular da acuidade visual (n=16; 64,0%). As principais alterações oftalmológicas encontradas foram: nistagmo (n=17; 68,0%), aumento da escavação do disco óptico e/ou palidez (n=13; 52,0%), estrabismo (n=12; 48,0%) e comportamento visual pobre (n=9; 36,0%). Conclusão: Em crianças com tumor da via óptica e incapazes de responder aos testes de acuidade visual de reconhecimento, foi possível quantificar deficiência visual por meio dos potenciais visuais evocados de varredura e avaliar a diferença interocular da acuidade visual de grades. A gravidade do déficit da acuidade visual de grades relacionado à idade e a diferença interocular da acuidade visual de grades foram congruentes com alterações oftalmológicas e neuroimagem. O déficit da acuidade visual de grades foi útil à caracterização do estado visual em crianças com tumores da via óptica e ao embasamento da assistência neuro-oncológica.(AU)
Subject(s)
Humans , Child , Visual Pathways/pathology , Visual Acuity , Optic Nerve Glioma/pathology , Vision Disorders/etiology , Evoked Potentials, VisualABSTRACT
Past work has demonstrated that active suppression of salient distractors is a critical part of visual selection. Evidence for goal-driven suppression includes below-baseline visual encoding at the position of salient distractors (Gaspelin and Luck, 2018) and neural signals such as the distractor positivity (Pd) that track how many distractors are presented in a given hemifield (Feldmann-Wüstefeld and Vogel, 2019). One basic question regarding distractor suppression is whether it is inherently spatial or nonspatial in character. Indeed, past work has shown that distractors evoke both spatial (Theeuwes, 1992) and nonspatial forms of interference (Folk and Remington, 1998), motivating a direct examination of whether space is integral to goal-driven distractor suppression. Here, we use behavioral and EEG data from adult humans (male and female) to provide clear evidence for a spatial gradient of suppression surrounding salient singleton distractors. Replicating past work, both reaction time and neural indices of target selection improved monotonically as the distance between target and distractor increased. Importantly, these target selection effects were paralleled by a monotonic decline in the amplitude of the Pd, an electrophysiological index of distractor suppression. Moreover, multivariate analyses revealed spatially selective activity in the θ-band that tracked the position of the target and, critically, revealed suppressed activity at spatial channels centered on distractor positions. Thus, goal-driven selection of relevant over irrelevant information benefits from a spatial gradient of suppression surrounding salient distractors.SIGNIFICANCE STATEMENT Past work has shown that distractor suppression is an important part of goal-driven attentional selection, but has not yet revealed whether suppression is spatially directed. Using behavioral data, event-related potentials (ERPs) of the EEG signal [N2pc and distractor positivity (Pd) component], as well as a multivariate model of EEG data [channel tuning functions (CTF)], we show that suppression-related neural activity increases monotonically as the distance between targets and distractors decreases, and that spatially-selective activity in the θ-band reveals depressed activity in spatial channels that index distractor positions. Thus, we provide robust evidence for spatially-guided distractor suppression, a result that has important implications for models of goal-driven attentional control.
Subject(s)
Attention/physiology , Evoked Potentials, Visual/physiology , Photic Stimulation/methods , Reaction Time/physiology , Space Perception/physiology , Adolescent , Adult , Electroencephalography/methods , Female , Humans , Male , Visual Perception/physiology , Young AdultABSTRACT
PURPOSE: To determine visual impairment due to optic pathway tumors in children unable to perform recognition acuity tests. METHODS: Grating visual acuity scores, in logMAR, were obtained by sweep visually evoked potentials (SVEP) in children with optic pathway tumors. The binocular grating visual acuity deficit was calculated by comparison with age-based norms and then assigned to categories of visual impairment as mild (from 0.10 to 0.39 logMAR), moderate (from 0.40 to 0.79 logMAR), or severe (≥0.80 logMAR). Interocular differences were calculated by subtraction and considered increased if >0.10 logMAR. RESULTS: The participants were 25 children (13 boys; mean ± SD age, 35.1 ± 25.9 months; median age, 32.0 months) with optic pathway tumors (24 gliomas and 1 embryonal tumor), mostly located at the hypothalamic-chiasmatic transition (n=21; 84.0%) with visual abnormalities reported by parents (n=17; 68.0%). The mean grating acuity deficit was 0.60 ± 0.36 logMAR (median, 0.56 logMAR). Visual impairment was detected in all cases and was classified as mild in 10 (40.0%), moderate in 8 (32.0%), and severe in 7 (28.0%) children, along with increased interocular differences (>0.1 logMAR) (n=16; 64.0%). The remarkable ophthalmological abnormalities were nystagmus (n=17; 68.0%), optic disc cupping and/or pallor (n=13; 52.0%), strabismus (n=12; 48.0%), and poor visual behavior (n=9; 36.0%). CONCLUSION: In children with optic pathway tumors who were unable to perform recognition acuity tests, it was possible to quantify visual impairment by sweep-visually evoked potentials and to evaluate interocular differences in acuity. The severity of age-based grating visual acuity deficit and interocular differences was in accordance with ophthalmological abnormalities and neuroimaging results. Grating visual acuity deficit is useful for characterizing visual status in children with optic pathway tumors and for supporting neuro-oncologic management.