Contingent negative variation (CNV) associated with sensorimotor timing error correction.

INTRODUCTION: Detection and subsequent correction of sensorimotor timing errors are fundamental to adaptive behavior. Using scalp-recorded event-related potentials (ERPs), we sought to find ERP components that are predictive of error correction performance during rhythmic movements. METHOD: Healthy right-handed participants were asked to synchronize their finger taps to a regular tone sequence (every 600ms), while EEG data were continuously recorded. Data from 15 participants were analyzed. Occasional irregularities were built into stimulus presentation timing: 90ms before (advances: negative shift) or after (delays: positive shift) the expected time point. A tapping condition alternated with a listening condition in which identical stimulus sequence was presented but participants did not tap. RESULTS: Behavioral error correction was observed immediately following a shift, with a degree of over-correction with positive shifts. Our stimulus-locked ERP data analysis revealed, 1) increased auditory N1 amplitude for the positive shift condition and decreased auditory N1 modulation for the negative shift condition; and 2) a second enhanced negativity (N2) in the tapping positive condition, compared with the tapping negative condition. In response-locked epochs, we observed a CNV (contingent negative variation)-like negativity with earlier latency in the tapping negative condition compared with the tapping positive condition. This CNV-like negativity peaked at around the onset of subsequent tapping, with the earlier the peak, the better the error correction performance with the negative shifts while the later the peak, the better the error correction performance with the positive shifts. DISCUSSION: This study showed that the CNV-like negativity was associated with the error correction performance during our sensorimotor synchronization study. Auditory N1 and N2 were differentially involved in negative vs. positive error correction. However, we did not find evidence for their involvement in behavioral error correction. Overall, our study provides the basis from which further research on the role of the CNV in perceptual and motor timing can be developed

Sensorimotor Synchronization With Auditory and Visual Modalities: Behavioral and Neural Differences

It has long been known that the auditory system is better suited to guide temporally precise behaviors like sensorimotor synchronization (SMS) than the visual system. Although this phenomenon has been studied for many years, the underlying neural and computational mechanisms remain unclear. Growing consensus suggests the existence of multiple, interacting, context-dependent systems, and that reduced precision in visuo-motor timing might be due to the way experimental tasks have been conceived. Indeed, the appropriateness of the stimulus for a given task greatly influences timing performance. In this review, we examine timing differences for sensorimotor synchronization and error correction with auditory and visual sequences, to inspect the underlying neural mechanisms that contribute to modality differences in timing. The disparity between auditory and visual timing likely relates to differences in the processing specialization between auditory and visual modalities (temporal vs. spatial). We propose this difference could offer potential explanation for the differing temporal abilities between modalities. We also offer suggestions as to how these sensory systems interface with motor and timing systems

Análise do eletroencefalograma durante estimulação visual por realidade virtual estereoscópica em tarefa de interceptação de bola

This Thesis developed a voluntary movement evaluation protocol, composed by a ball interception task, in a stereoscopic virtual reality environment. Thirty one righthanded volunteers participated of the experimental protocol, that simulated the point of view of goal keeper during soccer penalty defense, with three types of random stimuli, 28 each: left, centered and right ball. Two segments of EEG signals were studied in order to observe the expectancy-related potential (CNV). (1) 2 s before the beginning of the movement detected by the accelerometer and (2) 4 s between the sound of the whistle and the beginning of the movement of the ball. The epochs composed by the segment (2), present a higher CNV (p 0.05), but by the cortical responses (p < 0.05), and only after the ball initiate your trajectory (p < 0.001). Therefore, it seems that the ball direction influence the complexity of cortical responses after the beginning of the ball’s motion. Forma adicional Também disponível on-line.Esta Tese desenvolveu um protocolo de avaliação do movimento voluntário composto pela tarefa de interceptação de bola, em um ambiente de realidade virtual estereoscópica. Trinta e um voluntários destros participaram do protocolo experimental, que simulava a defesa de um pênalti do futebol a partir do ponto de vista de um goleiro, dividido em três tipos de estímulos: bola à esquerda, ao centro e à direita, sendo 28 estímulos, ordenados aleatoriamente, para cada um. Foram estudados dois trechos com vistas a observar o potencial de expectativa relacionado ao movimento (CNV): (1) 2 s antes do início do movimento detectado pelo acelerômetro e (2) 4 s compreendidos entre o som do apito e o início do movimento da bola. As épocas compostas pelo trecho (2) apresentaram uma maior CNV (p 0,05), mas sim pelas respostas corticais (p < 0,05), e somente após a bola iniciar sua trajetória (p < 0,001). Portanto, os resultados indicam que a direção da bola influencia a complexidade cortical após o início do movimento da bola

Performance monitoring during action observation and auditory lexical decisions

How does the brain monitor performances? Does expertise modulate this process? How does an observer’s error related activity differ from a performers own error related activity? How does ambiguity change the markers of error monitoring? In this thesis, I present two EEG studies and a commentary that sought to answer these questions. Both empirical studies concern performance monitoring in two different contexts and from two different personal perspectives, i.e. investigating the effects of expertise on electroencephalographic (EEG) neuromarkers of performance monitoring and in terms of monitoring own and others’ errors during actions and language processing. My first study focused on characterizing the electrophysiological responses in experts and control individuals while they are observing domain-specific actions in wheelchair basketball with correct and wrong outcomes (Chapter II). The aim of the commentary in the following chapter was to highlight the role of Virtual Reality approaches to error prediction during one’s own actions (Chapter III). The fourth chapter hypothesised that the error monitoring markers are present during both one’s own performance errors in a lexical decision task, and the observation of others’ performance errors (Chapter IV), however, the results suggested a further modulation of uncertainty created by our task design. The final chapter presents a general discussion that provides an overview of the results of my PhD work (Chapter V). The present chapter consists of a literature review in the leading frameworks of performance monitoring, action observation, visuo-motor expertise and language processing