N1 Potential Research Articles

Is the dolphin a fish? ERP evidence for the impact of typicality during early visual processing in ultra-rapid semantic categorization in autism spectrum disorder

BackgroundNeurotypical individuals categorize items even during ultra-rapid presentations (20 ms; see Thorpe et al. Nature 381: 520, 1996). In cognitively able autistic adults, these semantic categorization processes may be impaired and/or may require additional time, specifically for the categorization of atypical compared to typical items. Here, we investigated how typicality structures influence ultra-rapid categorization in cognitively able autistic and neurotypical male adults.MethodsImages representing typical or atypical exemplars of two different categories (food/animals) were presented for 23.5 vs. 82.3 ms (short/long). We analyzed detection rates, reaction times, and the event-related potential components dN150, N1, P2, N2, and P3 for each group.ResultsBehavioral results suggest slower and less correct responses to atypical compared to typical images. This typicality effect was larger for the category with less distinct boundaries (food) and observed in both groups. However, electrophysiological data indicate a different time course of typicality effects, suggesting that neurotypical adults categorize atypical images based on simple features (P2), whereas cognitively able autistic adults categorize later, based on arbitrary features of atypical images (P3).ConclusionsWe found evidence that all three factors under investigation — category, typicality, and presentation time — modulated specific aspects of semantic categorization. Additionally, we observed a qualitatively different pattern in the autistic adults, which suggests that they relied on different cognitive processes to complete the task.

A rare scare: The role of intolerance of uncertainty in startle responses and event-related potentials in anticipation of unpredictable threat

Intolerance of uncertainty (IU) represents a transdiagnostic risk factor for internalizing psychopathology. However, little is known regarding its psychophysiological correlates. IU is thought to render individuals hypersensitive to threatening events, even if the occurrence probability is low. To test this, we recruited 90 students who completed two NPU-threat tests separating temporal unpredictability from probabilistic unpredictability (i.e., probability of occurrence): First, a NPU version in which the timing of threat (i.e., shock) was either predictable or unpredictable but the shock probability was 100 % in each trial. Second, a probabilistic NPU version in which the timing of the shock was also either predictable or unpredictable, but the shock probability was 33 % in each trial. Startle reflex, event-related potentials N1 and P3 locked to auditory startle probes, and anxiety ratings were analyzed. As expected, temporally unpredictable threat modulated startle, N1, and anxiety ratings. IU predicted increased startle to lower shock probability, regardless of the temporal predictability. No evidence emerged for IU affecting N1 or P3. However, IU predicted anxiety ratings to threat conditions regardless of temporal or probabilistic predictability. Individual differences in IU shape startle responses to eventual threat: IU increases automatic defensive responding to unpredictable and potentially threatening situations if the threat probability is low. Individuals with higher IU may tend to “err on the side of caution” with a mismatch between physiological preparation and threat probability, such that the effects of IU are particularly observable in low threat probability conditions.

Analysis of the phenomenon of "attention shift" as a marker of psycho-emotional stress

Compliance with the principles of mental health is a priority task in the education of children and adolescents. Researchers present the results of the analysis of psychophysiological studies, mostly by foreign authors, devoted to the problem of biomarkers of psycho-emotional stress (anxiety, aggression). The authors have considered the phenomenon of attention biases (attention shifts), as well as behavioral inhibition. We have analyzed the role of bioelectric asymmetry of the frontal areas of the brain, amygdala and prefrontal cortex. Scientists have shown the role of two basic motivational systems of approach/achievement ("approach system") and avoidance/withdrawal ("withdrawal system"). The use of adequate psychophysiological tests, such as: dot-probe tasks, attention shifting tasks, temporal order judgment tasks, visual search tasks allows you to best identify attention shifts and observe changes in the bioelectric activity of the brain. The asymmetry of the EEG of the frontal areas of the brain; the ratios of slow EEG waves to fast ones (theta / beta ratio; delta / beta ratio); changes in the parameters of the components of the evoked potentials P1, N1, N2 and late positive potential (LPP) with attention shifts you can consider as markers of psychoemotional tension. You can take into account the understanding of the mechanisms of shifting attention to threatening information in anxious children and adolescents in the prevention of mental health and to create corrective methods of training the system of attention to information with the opposite motivating value, allowing for adaptive behavior in the future.

Reverse pharmacology of Nimbin-N2 attenuates alcoholic liver injury and promotes the hepatoprotective dual role of improving lipid metabolism and downregulating the levels of inflammatory cytokines in zebrafish larval model.

Alcoholic liver disease is one of the most prominent liver diseases in the world. Lipid accumulation accompanied by oxidative stress and inflammation in the liver is the most important pathogenesis of ALD. This study was designed to investigate the anti-oxidative, fat metabolism-regulating, and anti-inflammatory potential of N2, a seminatural analog of Nimbin. The ethanol exposure was found to induce liver injury on zebrafish larvae, such as liver inflammation, lipid accumulation, oxidative stress, and hepatocytes apoptosis. N2 was subjected to ADMET screening in-silico, and it was observed N2's co-exposure decreased the ROS, apoptosis, lipid peroxidation, and macrophage accumulation in the liver of larval zebrafish. To further study the mechanism behind ethanol hepatotoxicity and the hepatoprotective behavior of N2, gene expression changes were determined in zebrafish. The results of this study revealed that ethanol exposure upregulated mRNA expressions of SREBP1, C/EBP-α, FAS and provoked more severe oxidative stress and hepatitis via upregulation of inflammatory cytokines TNF-α, IL-10, IL-1β, iNOS, COX-2. However, the N2 co-exposure protected the hepatocyte damage and almost reversed the condition by downregulating the mRNA levels. The study suggested that N2 could be an effective therapeutic agent for the treatment of ALD and other inflammatory conditions.

Influence of Environmental Aesthetic Value and Anticipated Emotion on Pro-Environmental Behavior: An ERP Study.

Perceptual cues act as signals in the aesthetic value environment, which promote emotion regulation toward pro-environment behavior. This type of perception-emotion-behavior reactivity forms the core of human altruism. However, differences in pro-environmental behavior may result from variation across high-aesthetic-value (HAV) and low-aesthetic-value (LAV) environments. This study investigated the neural mechanisms underlying interaction effects between environmental context and emotion regulation on pro-environmental behavior by integrating behavioral and temporal dynamics of decision-making information processing with event-related potential (ERP) technique measures. The results indicated that changing anticipated emotions changes pro-environmental behavior. Regarding changing aesthetic value environments, while modulating emotion regulation, significant differences were found in brain regions and mean amplitudes of N1, P2, N2, and late positive potential (LPP) components, which anticipated emotion. The findings suggest that environmental aesthetic value and emotion regulation impact pro-environmental behavior.

Neural Markers of Auditory Response and Habituation in Phelan-McDermid Syndrome.

Phelan-McDermid Syndrome (PMS) is a rare genetic disorder caused by deletion or sequence variation in the SHANK3 gene at terminal chromosome 22 that confers high likelihood of comorbid autism spectrum disorder (ASD). Whereas individuals with idiopathic ASD (iASD) can demonstrate diverse patterns of sensory differences, PMS is mainly characterized by sensory hyporesponsiveness. This study used electrophysiology and a passive auditory habituation paradigm to test for neural markers of hyporesponsiveness. EEG was recorded from 15 individuals with PMS, 15 with iASD, and 16 with neurotypical development (NT) while a series of four consecutive 1,000 Hz tones was repeatedly presented. We found intact N1, P2, and N2 event-related potentials (ERPs) and habituation to simple auditory stimuli, both in individuals with iASD and in those with PMS. Both iASD and PMS groups showed robust responses to the initial tone and decaying responses to each subsequent tone, at levels comparable to the NT control group. However, in PMS greater initial N1 amplitude and habituation were associated with auditory hypersensitivity, and P2 habituation correlated with ASD symptomatology. Additionally, further classification of the PMS cohort into genetic groupings revealed dissociation of initial P2 amplitude and habituation of N1 based on whether the deletions included additional genes beyond solely SHANK3 and those not thought to contribute to phenotype. These results provide preliminary insight into early auditory processing in PMS and suggest that while neural response and habituation is generally preserved in PMS, genotypic and phenotypic characteristics may drive some variability. These initial findings provide early evidence that the robust pattern of behavioral hyporesponsiveness in PMS may be due, at least in audition, to higher order factors.

Electrically evoked auditory cortical responses elicited from individually fitted stimulation parameters in cochlear implant users

Objective To investigate electrically evoked auditory cortical responses (eACR) elicited from the stimulation of intracochlear electrodes based on individually fitted stimulation parameters in cochlear implant (CI) users. Design An eACR setup based on individual fitting parameters is proposed. A 50-ms alternating biphasic pulse train was used to stimulate apical, medial, and basal electrodes and to evoke auditory cortical potentials (N1-P2 complex). Study sample The eACR setup proposed was validated with 14 adult CI users. Results Individual and grand-average eACR waveforms were obtained. The eACR amplitudes were lower in the basal than in the apical and medial regions. Earlier N1 latencies were found in CI users with lower maximum comfortable loudness levels and shorter phase duration in response to apical stimulation, while medial and basal stimulation resulted in earlier N1 latencies and larger N1-P2 amplitudes in users with longer CI experience. Conclusions eACR could be elicited by direct intracochlear stimulation using individual fitting parameters with a success rate of 71%. The highest cortical peak-to-peak amplitudes were obtained in response to apical stimulation. Unlike the P2, the N1 component appeared to be a consistent cortical potential to determine eACR and gain knowledge of the auditory processing beyond the cochlea in CI users. Highlights eACR can be elicited through direct stimulation of intracochlear electrodes. Stimulation of apical and medial regions yielded the highest N1-P2 amplitudes. CI users with lower maximum comfortable loudness levels had shorter N1 latencies during apical stimulation. The present dataset of mainly well-performing CI users suggests better cortical processing, that is, higher amplitudes and shorter latencies of N1. The N1 potential appears a more consistent and reliable potential than the P2 to determine eACR responses in CI users.

Global benefits of non-continuous flooding to reduce greenhouse gases and irrigation water use without rice yield penalty.

Non-continuous flooding is an effective practice for reducing greenhouse gas (GHG) emissions and irrigation water use (IRR) in rice fields. However, advancing global implementation is hampered by the lack of comprehensive understanding of GHGs and IRR reduction benefits without compromising rice yield. Here, we present the largest observational data set for such effects as of yet. By using Random Forest regression models based on 636 field trials at 105 globally georeferenced sites, we identified the key drivers of effects of non-continuous flooding practices and mapped maximum GHGs or IRR reduction benefits under optimal non-continuous flooding strategies. The results show that variation in effects of non-continuous flooding practices are primarily explained by the UnFlooded days Ratio (UFR, that is the ratio of the number of days without standing water in the field to total days of the growing period). Non-continuous flooding practices could be feasible to be adopted in 76% of global rice harvested areas. This would reduce the global warming potential (GWP) of CH4 and N2 O combined from rice production by 47% or the total GWP by 7% and alleviate IRR by 25%, while maintaining yield levels. The identified UFR targets far exceed currently observed levels particularly in South and Southeast Asia, suggesting large opportunities for climate mitigation and water use conservation, associated with the rigorous implementation of non-continuous flooding practices in global rice cultivation.

Limited Ability to Adjust N2 Amplitude During Dual Task Walking in People With Drug-Resistant Juvenile Myoclonic Epilepsy.

Juvenile myoclonic epilepsy (JME) is one of the most common epileptic syndromes; it is estimated to affect 1 in 1,000 people worldwide. Most people with JME respond well to medication, but up to 30% of them are drug-resistant. To date, there are no biomarkers for drug resistance in JME, and the poor response to medications is identified in retrospect. People with JME have frontal dysfunction manifested as impaired attention and difficulties in inhibiting habitual responses and these dysfunctions are more pronounced in drug-resistant individuals. Frontal networks play an important role in walking and therefore, gait can be used to overload the neural system and expose subtle changes between people with drug-responsive and drug-resistant JME. Electroencephalogram (EEG) is a promising tool to explore neural changes during real-time functions that combine a cognitive task while walking (dual tasking, DT). This exploratory study aimed to examine the alteration in electrical brain activity during DT in people with drug-responsive and drug-resistant JME. A total of 32 subjects (14 males and 18 females) participated: 11 drug-responsive (ages: 31.50 ± 1.50) and 8 drug-resistant (27.27 ± 2.30) people with JME, and 13 healthy controls (29.46 ± 0.69). The participants underwent EEG examination during the performance of the visual Go/NoGo (vGNG) task while sitting and while walking on a treadmill. We measured latencies and amplitudes of N2 and P3 event-related potentials, and the cognitive performance was assessed by accuracy rate and response time of Go/NoGo events. The results demonstrated that healthy controls had earlier N2 and P3 latencies than both JME groups (N2: p = 0.034 and P3: p = 0.011), however, a limited ability to adjust the N2 amplitude during walking was noticeable in the drug-resistant compared to drug-responsive. The two JME groups had lower success rates (drug-responsive p < 0.001, drug-resistant p = 0.004) than healthy controls, but the drug-resistant showed longer reaction times compared to both healthy controls (p = 0.033) and drug-responsive (p = 0.013). This study provides the first evidence that people with drug-resistant JME have changes in brain activity during highly demanding tasks that combine cognitive and motor functions compared to people with drug-responsive JME. Further research is needed to determine whether these alterations can be used as biomarkers to drug response in JME.

Anti-inflammatory role demonstrated both in vitro and in vivo models using nonsteroidal tetranortriterpenoid, Nimbin (N1) and its analogs (N2 and N3) that alleviate the domestication of alternative medicine.

Human health may benefit from the study of natural compounds and phytoconstituents that can protect from inflammation. We investigated Nimbin (N1), a member of the ring C Seco-tetranortriterpenoids family, and its semi-natural analog deacetyl Nimbin namely N2 and N3 for their anti-inflammatory properties. As key findings, N1, N2, and N3 were able to improve wound healing by cell proliferation in a period of 24 h and were able to reduce the reactive oxygen species (ROS) production in Madin-Darby Canine Kidney cells which were screened using dichloro-dihydro fluorescein diacetate (DCF-DA) staining. When the zebrafish larvae were subjected to DCF-DA assay N1, N2, and N3 were able to substantially reduce the ROS levels in a dose-dependent manner. In zebrafish larvae, the cell death indicates the fluorescent intensity due to acridine orange staining that was found to be dramatically decreasing upon the treatment of N1, N2, and N3. The cell membrane lipid peroxidation levels were also reduced in a dose-dependent manner upon the treatment of Nimbin and its analogs indicating lesser blue fluorescent levels. Among the Nimbin and its analogs, N2 was subjected to have better activity. To confirm the activity of N1, N2, and N3, in silico characterization was performed using Density functional theory and molecular docking. As a result, N2 exhibited the lowest electronegative value and highest binding energy when docked with anti-inflammatory and antioxidant proteins CAT, COX, GP, IL-1, and MPO. Furthermore, the therapeutic potential of N2 must be explored at the molecular level as well as in clinical studies for the treatment of inflammation-associated diseases.

Impaired Inhibitory Control During Walking in Parkinson's Disease Patients: An EEG Study.

The performance on a visual Go/NoGo (VGNG) task during walking has been used to evaluate the effect of gait on response inhibition in young and older adults; however, no work has yet included Parkinson's disease (PD) patients for whom such changes may be even more enhanced. In this study, we aimed to explore the effect of gait on automatic and cognitive inhibitory control phases in PD patients and the associated changes in neural activity and compared them with young and older adults. 30 PD patients, 30 older adults, and 11 young adults performed a visual Go/NoGo task in a sitting position and during walking on a treadmill while their EEG activity and gait were recorded. Brain electrical activity was evaluated by the amplitude, latency, and scalp distribution of N2 and P300 event related potentials. Mix model analysis was used to examine group and condition effects on task performance and brain activity. The VGNG accuracy rates in PD patients during walking were lower than in young and older adults (F = 5.619, p = 0.006). For all groups, N2 latency during walking was significantly longer than during sitting (p = 0.013). In addition, P300 latency was significantly longer in PD patients (p < 0.001) and older adults (p = 0.032) during walking compared to sitting and during 'NoGo' trials compared with 'Go' trials. Moreover, the young adults showed the smallest number of electrodes for which a significant differential activation between sit to walk was observed, while PD patients showed the largest with N2 being more strongly manifested in bilateral parietal electrodes during walking and in frontocentral electrodes while seated. The results show that response inhibition during walking is impaired in older subjects and PD patients and that increased cognitive load during dual-task walking relates to significant change in scalp electrical activity, mainly in parietal and frontocentral channels.

Response Inhibition and Predicting Response to Pharmacological and Cognitive Behavioral Therapy Treatments for Major Depressive Disorder: A Canadian Biomarker Integration Network for Depression Study

BackgroundMajor depressive disorder (MDD) is associated with various cognitive impairments, including response inhibition. Deficits in response inhibition may also underlie poor antidepressant treatment response. Recent studies revealed that the neurobiological correlates of response inhibition can predict response to pharmacological treatments. However, the generalizability of this finding to first-line nonpharmacological treatments, particularly cognitive behavioral therapy, remains to be investigated. MethodsData from two independent treatment protocols were combined, one in which 65 patients with MDD underwent treatment with escitalopram, and the other in which 41 patients with MDD underwent a course of cognitive behavioral therapy. A total of 25 healthy control subjects were also recruited. Neural correlates of response inhibition were captured by participants completing a Go/NoGo task during electroencephalography recording. Response inhibition–related measures of interest included the amplitudes of the N2 and P3 event-related potentials. ResultsPretreatment P3 amplitude, which has been linked to both the motor and cognitive aspects of response inhibition, was a significant predictor of change in depressive symptoms following escitalopram and cognitive behavioral therapy treatment. A greater pretreatment P3 amplitude was associated with a greater reduction in depressive severity. In addition, the pretreatment P3 amplitude was found to be significantly greater at baseline in remitters than in nonremitters and healthy control subjects. ConclusionsThe integrity of response inhibition may be critical for a successful course of pharmacological or psychological treatment for MDD. Electrophysiological correlates of response inhibition may have utility as a general prognostic marker of treatment response in MDD. Future studies may investigate the benefit of preceding first-line treatments with interventions that improve response inhibition in MDD.

Assessment of Biomechanical Predictors of Occurrence of Low-Amplitude N1 Potentials Evoked by Naturally Occurring Postural Instabilities.

Naturally occurring postural instabilities that occur while standing and walking elicit specific cortical responses in the fronto-central regions (N1 potentials) followed by corrective balance responses to prevent falling. However, no framework could simultaneously track different biomechanical parameters preceding N1s, predict N1s, and assess their predictive power. Here, we propose a framework and show its utility by examining cortical activity (through electroencephalography [EEG]), ground reaction forces, and head acceleration in the anterior-posterior (AP) direction. Ten healthy young adults carried out a balance task of standing on a support surface with or without sway referencing in the AP direction, amplifying, or dampening natural body sway. Using independent components from the fronto-central cortical region obtained from subject-specific head models, we first robustly validated a prior approach on identifying low-amplitude N1 potentials before early signs of balance corrections. Then, a machine learning algorithm was used to evaluate different biomechanical parameters obtained before N1 potentials, to predict the occurrence of N1s. When different biomechanical parameters were directly compared, the time to boundary (TTB) was found to be the best predictor of the occurrence of upcoming low-amplitude N1 potentials during a balance task. Based on these findings, we confirm that the spatio-temporal characteristics of the center of pressure (COP) might serve as an essential parameter that can facilitate the early detection of postural instability in a balance task. Extending our framework to identify such biomarkers in dynamic situations like walking might improve the implementation of corrective balance responses through brain-machine-interfaces to reduce falls in the elderly.

The timecourse of multisensory speech processing in unilaterally stimulated cochlear implant users revealed by ERPs

A cochlear implant (CI) is an auditory prosthesis which can partially restore the auditory function in patients with severe to profound hearing loss. However, this bionic device provides only limited auditory information, and CI patients may compensate for this limitation by means of a stronger interaction between the auditory and visual system. To better understand the electrophysiological correlates of audiovisual speech perception, the present study used electroencephalography (EEG) and a redundant target paradigm. Postlingually deafened CI users and normal-hearing (NH) listeners were compared in auditory, visual and audiovisual speech conditions. The behavioural results revealed multisensory integration for both groups, as indicated by shortened response times for the audiovisual as compared to the two unisensory conditions. The analysis of the N1 and P2 event-related potentials (ERPs), including topographic and source analyses, confirmed a multisensory effect for both groups and showed a cortical auditory response which was modulated by the simultaneous processing of the visual stimulus. Nevertheless, the CI users in particular revealed a distinct pattern of N1 topography, pointing to a strong visual impact on auditory speech processing. Apart from these condition effects, the results revealed ERP differences between CI users and NH listeners, not only in N1/P2 ERP topographies, but also in the cortical source configuration. When compared to the NH listeners, the CI users showed an additional activation in the visual cortex at N1 latency, which was positively correlated with CI experience, and a delayed auditory-cortex activation with a reversed, rightward functional lateralisation. In sum, our behavioural and ERP findings demonstrate a clear audiovisual benefit for both groups, and a CI-specific alteration in cortical activation at N1 latency when auditory and visual input is combined. These cortical alterations may reflect a compensatory strategy to overcome the limited CI input, which allows the CI users to improve the lip-reading skills and to approximate the behavioural performance of NH listeners in audiovisual speech conditions. Our results are clinically relevant, as they highlight the importance of assessing the CI outcome not only in auditory-only, but also in audiovisual speech conditions.

Early evoked brain activity underlies auditory and audiovisual speech recognition deficits in schizophrenia

ObjectivesPeople with Schizophrenia (SZ) show deficits in auditory and audiovisual speech recognition. It is possible that these deficits are related to aberrant early sensory processing, combined with an impaired ability to utilize visual cues to improve speech recognition. In this electroencephalography study we tested this by having SZ and healthy controls (HC) identify different unisensory auditory and bisensory audiovisual syllables at different auditory noise levels. MethodsSZ (N = 24) and HC (N = 21) identified one of three different syllables (/da/, /ga/, /ta/) at three different noise levels (no, low, high). Half the trials were unisensory auditory and the other half provided additional visual input of moving lips. Task-evoked mediofrontal N1 and P2 brain potentials triggered to the onset of the auditory syllables were derived and related to behavioral performance. ResultsIn comparison to HC, SZ showed speech recognition deficits for unisensory and bisensory stimuli. These deficits were primarily found in the no noise condition. Paralleling these observations, reduced N1 amplitudes to unisensory and bisensory stimuli in SZ were found in the no noise condition. In HC the N1 amplitudes were positively related to the speech recognition performance, whereas no such relationships were found in SZ. Moreover, no group differences in multisensory speech recognition benefits and N1 suppression effects for bisensory stimuli were observed. ConclusionOur study suggests that reduced N1 amplitudes reflect early auditory and audiovisual speech processing deficits in SZ. The findings that the amplitude effects were confined to salient speech stimuli and the attenuated relationship with behavioral performance in patients compared to HC, indicates a diminished decoding of the auditory speech signals in SZs. Our study also revealed relatively intact multisensory benefits in SZs, which implies that the observed auditory and audiovisual speech recognition deficits were primarily related to aberrant processing of the auditory syllables.

Persistent N2 After Induction Is Not a Contraindication to Surgery for Lung Cancer

BackgroundSurgical management for potentially resectable stage IIIA-N2 non-small cell lung cancer (NSCLC) is controversial. For some, persistent N2 disease after induction therapy is a contraindication to resection. We examined outcomes of a well-selected surgical cohort of postinduction IIIA-N2 NSCLC patients with persistent N2 disease. MethodsWe retrospectively reviewed all resected clinical IIIA-N2 NSCLC patients from 2001 to 2018. Thorough preoperative staging, including invasive mediastinal staging, was performed. Those with nonbulky N2 disease, appropriate restaging, and potential for a margin-negative resection were included. After resection, patients were classified as having persistent N2 disease or mediastinal downstaging (N2 to >N0/N1). Persistent N2 patients were further classified as uncertain resection (R[un]) or complete resection (R0) according to the International Association for the Study of Lung Cancer definition. Kaplan-Meier survival analysis was used. ResultsFifty-four patients met inclusion criteria. After induction, 31 patients (57%) demonstrated persistent N2 disease, and 23 patients (43%) had mediastinal downstaging. Preinduction invasive mediastinal staging was performed in 98.1%. Most had clinical single-station N2 disease (75.9%). Margin-negative resections were performed in 100%. Eight patients were reclassified as R(un) due to positive highest sampled mediastinal station. The median overall survival for persistent N2 was 26 months for R(un) and 69 months for R0. Overall survival for the downstaged group was 67 months (P = .31). ConclusionsOverall survival for patients with non-R(un) or persistent N2 (true R0) was similar to those with mediastinal downstaging. Well-selected patients with persistent N2 disease experience reasonable survival after resection and should have surgery considered as part of their multimodality treatment. This study underscores the importance of classifying the extent of mediastinal involvement for persistent N2 patients, supporting the proposed International Association for the Study of Lung Cancer R(un) classification.

Auditory Information Accelerates the Visuomotor Reaction Speed of Elite Badminton Players in Multisensory Environments.

Although vision is the dominating sensory system in sports, many situations require multisensory integration. Faster processing of auditory information in the brain may facilitate time-critical abilities such as reaction speed however previous research was limited by generic auditory and visual stimuli that did not consider audio-visual characteristics in ecologically valid environments. This study investigated the reaction speed in response to sport-specific monosensory (visual and auditory) and multisensory (audio-visual) stimulation. Neurophysiological analyses identified the neural processes contributing to differences in reaction speed. Nineteen elite badminton players participated in this study. In a first recording phase, the sound profile and shuttle speed of smash and drop strokes were identified on a badminton court using high-speed video cameras and binaural recordings. The speed and sound characteristics were transferred into auditory and visual stimuli and presented in a lab-based experiment, where participants reacted in response to sport-specific monosensory or multisensory stimulation. Auditory signal presentation was delayed by 26 ms to account for realistic audio-visual signal interaction on the court. N1 and N2 event-related potentials as indicators of auditory and visual information perception/processing, respectively were identified using a 64-channel EEG. Despite the 26 ms delay, auditory reactions were significantly faster than visual reactions (236.6 ms vs. 287.7 ms, p < 0.001) but still slower when compared to multisensory stimulation (224.4 ms, p = 0.002). Across conditions response times to smashes were faster when compared to drops (233.2 ms, 265.9 ms, p < 0.001). Faster reactions were paralleled by a lower latency and higher amplitude of the auditory N1 and visual N2 potentials. The results emphasize the potential of auditory information to accelerate the reaction time in sport-specific multisensory situations. This highlights auditory processes as a promising target for training interventions in racquet sports.

Neural correlates of top-down attention in auditory and visual contexts reflect individual differences in the population

Individual variability in performance on selective attention tasks that require top-down control can be large. Recent neuroimaging and electroencephalography (EEG) experiments also suggest that auditory spatial selective attention engages the same fronto-parietal network used by visual spatial selective attention. We therefore hypothesized that individual differences in spatial selective attention would correlate for similar auditory and visual tasks and produce correlated changes in sensory responses in the two modalities. We calculated EEG-derived correlates of top-down, spatial attention during auditory and visual tasks that required subjects to sustain selective attention at one of two cued spatial locations (left or right) and report the auditory or visual sequence that appeared in that direction. Individual behavioral performance on the tasks correlated across sensory modalities. Spatial attention differentially modulated event-related potential N1 responses at the group level for both auditory and visual tasks. At the individual level, these attention-modulated N1 responses correlated with task performance for the auditory task; however, the ERP peaks were noisy and unreliable in the visual task. In contrast, the inter-trial coherence (ITC) in a time window encompassing the N1 correlated to performance for the visual, but not the auditory task. Our work highlights differences in how top-down attention modulates these representations across the two modalities.

Auditory deviance detection and involuntary attention allocation in occupational burnout-A follow-up study.

Here, we investigated the central auditory processing and attentional control associated with both recovery and prolongation of occupational burnout. We recorded the event-related brain potentials N1, P2, mismatch negativity (MMN) and P3a to nine changes in speech sounds and to three rarely presented emotional (happy, angry and sad) utterances from individuals with burnout (N = 16) and their matched controls (N = 12). After the 5 years follow-up, one control had acquired burnout, half (N = 8) of the burnout group had recovered, and the other half (prolonged burnout) still had burnout. The processing of acoustical changes in speech sounds was mainly intact. Prolongation of the burnout was associated with a decrease in MMN amplitude and an increase in P3a amplitude for the happy stimulus. The results suggest that, in the absence of interventions, burnout is a persistent condition, associated with alterations of attentional control, that may be amplified with the prolongation of the condition.

Contribution of different somatosensory afferent input to subcortical somatosensory evoked potentials in humans

ObjectivesTo investigate the subcortical somatosensory evoked potentials (SEPs) to electrical stimulation of either muscle or cutaneous afferents. MethodsSEPs were recorded in 6 patients suffering from Parkinson’s disease (PD) who underwent electrode implantation in the pedunculopontine (PPTg) nucleus area. We compared SEPs recorded from the scalp and from the intracranial electrode contacts to electrical stimuli applied to: 1) median nerve at the wrist, 2) abductor pollicis brevis motor point, and 3) distal phalanx of the thumb. Also the high-frequency oscillations (HFOs) were analysed. ResultsAfter median nerve and pure cutaneous (distant phalanx of the thumb) stimulation, a P1-N1 complex was recorded by the intracranial lead, while the scalp electrodes recorded the short-latency far-field responses (P14 and N18). On the contrary, motor point stimulation did not evoke any low-frequency component in the PPTg traces, nor the N18 potential on the scalp. HFOs were recorded to stimulation of all modalities by the PPTg electrode contacts. ConclusionsStimulus processing within the cuneate nucleus depends on modality, since only the cutaneous input activates the complex intranuclear network possibly generating the scalp N18 potential. SignificanceOur results shed light on the subcortical processing of the somatosensory input of different modalities.