Highlights • Sport expertise affects cognitive brain processes and behavioral performance in speeded tasks outside of the sport context. • Neural proficiency may represent a brain mechanism ...responsible for skilled performance. • Sport-specific practice can modulate brain functions and performances in a decision-making task. • Competitive sport training enhances not only sport-specific but also sport-general cognitive skills. • Public health should encourage fencing practice because it improves strongly both physical and cognitive skills.
Motor planning in older adults likely relies on the overengagement of the prefrontal cortex (PFC) and is associated with slowness of movement and responses. Does a physically active lifestyle ...counteract the overrecruitment of the PFC during action preparation? This study used high-resolution electroencephalography to measure the effect of physical exercise on the executive functions of the PFC preceding a visuomotor discriminative task. A total of 130 participants aged 15-86 were divided into two groups based on physical exercise participation. The response times and accuracy and the premotor activity of the PFC were separately correlated with age for the two groups. The data were first fit with a linear function and then a higher order polynomial function. We observed that after 35-40 years of age, physically active individuals have faster response times than their less active peers and showed no signs of PFC hyperactivity during motor planning. The present findings show that physical exercise could speed up the response of older people and reveal that also in middle-aged people, moderate-to-high levels of physical exercise benefits the planning/execution of a response and the executive functions mediated by the PFC, counteracting the neural overactivity often observed in the elderly adults.
The aim of this study was to assess the influence of age-related changes in cortical activity related to the motor preparation involved in simple- and discriminative-reaction tasks. To distinguish ...between age effects on motor planning and stimulus processing, both movement- and stimulus-locked event related potentials (ERPs) were investigated in 14 younger, 14 middle-aged, and 14 older adults (mean ages 24.4, 49, and 70years, respectively). The novel results of the present study are the prefrontal over-recruitment observed in older adults in movement-related cortical potentials (MRCPs) and the differential pattern of aging effects observed at behavioral and at electrophysiological level between middle-aged and older adults. Overall, the following results were observed: (i) behavioral results confirmed the well-known slowing of responses in aging people, which were associated with optimal accuracy; (ii) the age-related differences in cortical activity underlying the generation of voluntary movements in response to external stimuli were more pronounced for the motor planning than the stimulus processing stage; (iii) the source and the time-course analysis of the over-recruitment in the older adults indicated tonic involvement of prefrontal areas regardless of task complexity; and (iv) middle-aged adults showed a ‘young adult-like’ behavioral speed, but an ‘older adult-like’ overactivation of prefrontal areas. In summary, to reach the same accuracy, older subjects prepared the action with greater anticipation and higher cost, as indexed by the earlier latency onset and larger prefrontal cortical activation.
► Stimulus processing and motor planning across the adult life span were studied. ► During Go/No-Go task age-related slowing at behavioral and cognitive level was found. ► ERPs and source analyses showed age-related PFC over-recruitment. ► Elderly classify stimuli more slowly and prepare actions with large anticipation. ► The PFC hyperactivity is regardless of task complexity.
Key points
Monovision is an optical correction for presbyopes that consists of correcting one eye for far distance and the other for near distance, creating a superimposition of an in‐focus with a ...blurred image.
Brain adaptation to monovision was studied in unexperienced observers by measuring visual evoked potentials from 64‐channels.
The first clear effect of monovision on visual evoked potentials was the C1 amplitude reduction, indicating that the unilateral blurring induced by monovision reduces feed‐forward activity in primary visual area.
Monovision led also to an increased amplitude of the P1 and pP1 components, with the latter originating in prefrontal regions. This effect probably works as an attentional compensatory activity used to compensate for the degraded V1 signal.
A common and often successful option to correct presbyopia with contact lenses is monovision. This is an unbalanced correction across the two eyes where one eye is corrected for far vision and the other eye is corrected for near vision. Monovision is therefore a form of acquired anisometropia that causes a superimposition of an in‐focus image with a blurred image. In spite of this visual anisometropia, monovision has been successfully used for many decadesl however the brain mechanism supporting monovision is not well understood. The present study aimed to measure the visual evoked potentials with a high‐density electrode array (64‐channel) in a group of presbyopes and to provide a detailed spatiotemporal analysis of the cortical activity after a short period of adaptation to monovision with contact lenses. When compared with a balanced eye near correction, monovision produced both a clear reduction of the earliest visual evoked potential components, the C1 and the N1, and an amplitude increase of the P1 and pP1. These results indicate that the unilateral blurring induced by wearing monovision contact lenses reduces feed‐forward activity in the primary visual area and feedback activity in extrastriate areas (C1 and N1 reduction). Interestingly, other brain activities in both extrastriate visual areas (the P1 component) and in the anterior insula (the pP1 component) appear to compensate for this dysfunction, increasing their activity during monovision. These changes confirm the presence of fluid brain adaptation in visual and non‐visual areas during monocular interferences.
Key points
Monovision is an optical correction for presbyopes that consists of correcting one eye for far distance and the other for near distance, creating a superimposition of an in‐focus with a blurred image.
Brain adaptation to monovision was studied in unexperienced observers by measuring visual evoked potentials from 64‐channels.
The first clear effect of monovision on visual evoked potentials was the C1 amplitude reduction, indicating that the unilateral blurring induced by monovision reduces feed‐forward activity in primary visual area.
Monovision led also to an increased amplitude of the P1 and pP1 components, with the latter originating in prefrontal regions. This effect probably works as an attentional compensatory activity used to compensate for the degraded V1 signal.
In cognitive tasks, error commission is usually followed by a performance characterized by post-error slowing (PES) and post-error improvement of accuracy (PIA). Three theoretical accounts were ...hypothesized to support these post-error adjustments: the cognitive, the inhibitory, and the orienting account. The aim of the present ERP study was to investigate the neural processes associated with the second error prevention. To this aim, we focused on the preparatory brain activities in a large sample of subjects performing a Go/No-go task. The main results were the enhancement of the prefrontal negativity (pN) component -especially on the right hemisphere- and the reduction of the Bereitschaftspotential (BP) -especially on the left hemisphere- in the post-error trials. The ERP data suggested an increased top-down and inhibitory control, such as the reduced excitability of the premotor areas in the preparation of the trials following error commission. The results were discussed in light of the three theoretical accounts of the post-error adjustments. Additional control analyses supported the view that the adjustments-oriented components (the post-error pN and BP) are separated by the error-related potentials (Ne and Pe), even if all these activities represent a cascade of processes triggered by error-commission.
Several cognitive changes characterize normal aging; one change regards inhibitory processing and includes both conflict monitoring and response suppression. We attempted to segregate these two ...aspects within a Go/No-go task, investigating three age categories. Accuracy, response times and event-related potentials (ERPs) were recorded. The ERP data were analyzed, and the Go and No-go trials were separated; in addition, the trials were organized in repeat trials (in which the subjects repeated the action delivered in the previous trial) and switch trials (in which the subjects produced a response opposite to the previous response). We assumed that the switch trials conveyed more conflict than the repeat trials. In general, the behavioral data and slower P3 latencies confirmed the well-known age-related speed/accuracy trade-off. The novel analyses of the repeat vs. switch trials indicated that the age-related P3 slowing was significant only for the high conflict condition; the switch-P3 amplitude increased only in the two older groups. The 'aging switch effect' on the P3 component suggests a failure in the conflict conditions and likely contributes to a generalized dysfunction. The absence of either a switch effect in the young group and the P3 slowing in middle-aged group indicate that switching was not particularly demanding for these participants. The N2 component was less sensitive to the repeat/switch manipulation; however, the subtractive waves also enhanced the age effects in this earlier time window. The topographic maps showed other notable age effects: the frontal No-go N2 was nearly undetectable in the elderly; in the identical time window, a large activity in the posterior and prefrontal scalp regions was observed. Moreover, the prefrontal activity showed a negative correlation with false alarms. These results suggest that the frontal involvement during action suppression becomes progressively dysfunctional with aging, and additional activity was required to reach a good level of accuracy.
Event-related potentials (ERPs) are obtained from the electroencephalogram (EEG) or the magnetoencephalogram (MEG, event-related fields (ERF)), extracting the activity that is time-locked to an ...event. Despite the potential utility of ERP/ERF in cognitive domain, the clinical standardization of their use is presently undefined for most of procedures. The aim of the present review is to establish limits and reliability of ERP medical application, summarize main methodological issues, and present evidence of clinical application and future improvement. The present section of the review focuses on well-standardized ERP methods, including P300, Contingent Negative Variation (CNV), Mismatch Negativity (MMN), and N400, with a chapter dedicated to laser-evoked potentials (LEPs). One section is dedicated to proactive preparatory brain activity as the Bereitschaftspotential and the prefrontal negativity (BP and pN). The P300 and the MMN potentials have a limited but recognized role in the diagnosis of cognitive impairment and consciousness disorders. LEPs have a well-documented usefulness in the diagnosis of neuropathic pain, with low application in clinical assessment of psychophysiological basis of pain. The other ERP components mentioned here, though largely applied in normal and pathological cases and well standardized, are still confined to the research field. CNV, BP, and pN deserve to be largely tested in movement disorders, just to explain possible functional changes in motor preparation circuits subtending different clinical pictures and responses to treatments.
Fatigue has been defined as an exercise-induced decline in force generation capacity because of changes at both the peripheral and central levels. Movement is preceded and accompanied by brain ...activities related to the preparation and execution of movement (movement related cortical potentials, MRCP), which have been correlated with the perception of effort (RPE). We combined force measurements, surface electromyography (sEMG), peripheral electrical stimulation (maximal twitch, MT) and MRCP analysis to further our understanding of the neural correlates of peripheral and central changes during a fatiguing task involving the lower limbs. Eighteen healthy volunteers performed 4 blocks of isometric knee extensions at 40% of the maximal voluntary contraction (MVC) for a total of 240 2-s contractions. At the baseline and after each block, we measured RPE, MT and MVC. We simultaneously recorded the force of the knee extensor muscles, root mean square (RMS) of the sEMG of the vastus lateralis muscle, and electroencephalography (EEG) from 64 channels. The MRCPs were extracted from the EEG recordings and averaged in the early (Block 1-2) and late (Block 3-4) blocks. Two cohorts were obtained by cluster analysis based on the RPE (i.e., perception of effort) and MT (i.e., peripheral fatigue). We observed a significant decline in both the MVC (-13%) and RMS (-25%) of the sEMG signal over the course of the task; thus, muscle fatigue had occurred in all of the participants regardless of the cohort. The MRCP amplitude was larger in the fatigued than the non-fatigued MT cohort in the supplementary and premotor areas, whereas the MRCP amplitude was larger in the fatigued than the non-fatigued RPE cohort in the aforementioned areas, and also in the primary motor and prefrontal cortices (PFC). The increase in the positive activity of the PFC, along with the perception of effort, represents a novel result, suggesting that it is modulated more by the perception of effort than peripheral fatigue.
The existence of neural correlates of spatial attention is not limited to the reactive stage of stimulus processing: neural activities subtending spatial attention are deployed well ahead of stimulus ...onset. ERP evidence supporting this proactive (top-down) attentional control is based on trial-by-trial S1–S2 paradigms, where the onset of a directional cue (S1) indicates on which side attention must be directed to respond to an upcoming target stimulus (S2). Crucially, S1 onset trigger both attention and motor preparation, therefore, these paradigms are not ideal to demonstrate the effect of attention at preparatory stage of processing. To isolate top-down anticipatory attention, the present study used a sustained attention paradigm based on a steady cue that indicates the attended side constantly throughout an entire block of trials, without any onset of an attentional cue. The main result consists in the description of the attention effect on the visual negativity (vN) component, a growing neural activity starting before stimulus presentation in extrastriate visual areas. The vN was consistently lateralized in the hemisphere contralateral to the attended side, regardless of the hand to be used. At the opposite, the lateralized motor activity emerged long after, confirming that the hand-selection process followed the spatial attention orientation process. The present study confirms the anticipatory nature of the vN component and corroborate its role in terms of preparatory visuospatial attention.
•The prefrontal cortex is active prior to a perturbation of the lower limb.•Premotor and motor cortices are active before and after the perturbation.•A preparatory activity can be observed in the ...bilateral occipito-temporal cortex.
The contribution of higher-order cognitive functions to postural control is poorly understood. It is recognized that the prefrontal cortex (PFC) is active after postural perturbations, however little is known about anticipatory PFC activity occurring before an upcoming perturbation. Here we aim at advancing our understanding on the contribution of higher-order cognitive functions in the fore period before postural perturbations.
Thirteen healthy men underwent both self-paced and externally-triggered lower limb perturbations during high-resolution electroencephalography and surface electromyography (sEMG) recordings. Event-related potentials (ERP) and sEMG associated with perturbations were compared between conditions.
Both self-paced and externally-triggered perturbations elicited a large prefrontal negativity before the perturbation onset, but the externally-triggered condition evoked larger activity over the left hemisphere; source analysis localized this activity in the PFC. The motor readiness potential occurred earlier and was larger for self-paced perturbations and its origin in premotor areas was confirmed. A larger bilateral activity over lateral occipital derivations was observed for externally-triggered perturbations and was localized in the occipital-temporal cortex, likely within the extrastriate body area (EBA).
We confirm that the preparatory activity of premotor areas is associated with the intentional engagement of upcoming actions since it occurs only before self-paced perturbations. The PFC anticipating both perturbations can be interpreted as an unintentional top-down cognitive control required by the tasks, especially involving attention and inhibition. However, before externally-triggered perturbations also other cognitive resources are required. The EBA activity anticipating externally-triggered perturbation may represent a visual prediction of the desired posture.
PDF
