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The gray mouse lemur (Microcebus murinus) is considered a useful primate model for translational research. In the framework of IMI PharmaCog project (Grant Agreement n°115009, ), we tested the hypothesis that spectral electroencephalographic (EEG) markers of motor and locomotor activity in gray mouse lemurs reflect typical movement-related desynchronization of alpha rhythms (about 8–12 Hz) in humans. To this aim, EEG (bipolar electrodes in frontal cortex) and electromyographic (EMG; bipolar electrodes sutured in neck muscles) data were recorded in 13 male adult (about 3 years) lemurs. Artifact-free EEG segments during active state (gross movements, exploratory movements or locomotor activity) and awake passive state (no sleep) were selected on the basis of instrumental measures of animal behavior, and were used as an input for EEG power density analysis. Results showed a clear peak of EEG power density at alpha range (7–9 Hz) during passive state. During active state, there was a reduction in alpha power density (8–12 Hz) and an increase of power density at slow frequencies (1–4 Hz). Relative EMG activity was related to EEG power density at 2–4 Hz (positive correlation) and at 8–12 Hz (negative correlation). These results suggest for the first time that the primate gray mouse lemurs and humans may share basic neurophysiologic mechanisms of synchronization of frontal alpha rhythms in awake passive state and their desynchronization during motor and locomotor activity. These EEG markers may be an ideal experimental model for translational basic (motor science) and applied (pharmacological and non-pharmacological interventions) research in Neurophysiology. [ABSTRACT FROM AUTHOR]

Abstract: Different kinds of challenge can alter spontaneous ongoing electroencephalographic (EEG) rhythms in animal models, thus providing paradigms to evaluate treatment effects in drug discovery. The effects of challenges represented by pharmacological agents, hypoxia, sleep deprivation and transcranial magnetic stimulation (TMS) on EEG rhythms are here reviewed to build a knowledge platform for innovative translational models for drug discovery in Alzheimer’s disease (AD). It has been reported that antagonists of cholinergic neurotransmission cause synchronisation of spontaneous ongoing EEG rhythms in terms of enhanced power of EEG low frequencies and decreased power of EEG high frequencies. Acetylcholinesterase inhibitors and serotonergic drugs may restore a normal pattern of EEG desynchronisation. Sleep deprivation and hypoxia challenges have also been reported to elicit abnormal synchronisation of spontaneous ongoing EEG rhythms in rodents. The feasibility and reproducibility of TMS have been demonstrated in rodents but information on a consistent modulation of EEG after TMS manipulation is very limited. Transgenic mice over-expressing human amyloid precursor protein complementary DNAs (cDNAs) harbouring the ‘Swedish’ mutation and PS-1 cDNAs harbouring the A264E mutation, which recapitulate some of the pathological features of AD, exhibit alterations of spontaneous ongoing EEG rhythms at several low and high frequencies. This does not appear, however, to be a consequence of beta-amyloid deposition in the brain. The present review provides a critical evaluation of changes of spontaneous ongoing EEG rhythms due to the experimental manipulations described above, in order to stimulate the promote more adherent models fitting dynamics in humans. [Copyright &y& Elsevier]

Abstract: It has been shown that frontocentral electroencephalographic (EEG) alpha rhythms (about 10–12Hz) were higher in amplitude in expert golfers in successful than unsuccessful putts, possibly reflecting the idea that amplitude regulation of frontocentral alpha rhythms is a physiological mechanism implied in motor control and golfer''s performance (). Here, we tested the ancillary hypothesis that golfer''s performance is also associated to an improved coordination of cortical activity, as reflected by functional coupling of alpha rhythms across cortical regions. To this aim, between-electrodes spectral coherence was computed from spatially enhanced EEG data of the mentioned study (i.e. right handed 12 expert golfers; augmented 10–20 system; surface Laplacian estimation). Low- (about 8–10Hz) and high-frequency (about 10–12Hz) alpha sub-bands were considered with reference to individual alpha frequency peak. Statistical results showed that intra-hemispheric low-frequency alpha coherence in bilateral parietal–frontal (P3–F3 and P4–F4 electrodes) and parietal–central (P3–C3 and P4–C4 electrodes) was higher in amplitude in successful than unsuccessful putts (p<0.004). The same was true for intra-hemispheric high-frequency alpha coherence in bilateral parietal–frontal regions (p<0.004). These findings suggest that intra-hemispheric functional coupling of cortical alpha rhythms between “visuo-spatial” parietal area and other cortical areas is implicated in fine motor control of golfer''s performance. [Copyright &y& Elsevier]

Abstract: In the present study, we tested the hypothesis that compared with non-athletes, elite athletes are characterized by a reduction of reactivity of electroencephalographic (EEG) alpha rhythms (about 8–12Hz) to eyes opening in the condition of resting state, as a possible index of spatially selective cortical activation (i.e. “neural efficiency”). EEG data (56 channels; Eb-Neuro©) were recorded in 18 elite karate athletes and 28 non-athletes during resting state eyes-closed and eyes-open conditions. The EEG data were spatially enhanced by surface Laplacian estimation. Cortical activity was indexed by task-related power decrease (TRPD), namely the alpha power during the eyes-open referenced to the eyes-closed resting condition. Low-frequency alpha TRPD (about 8–10Hz) was lower in the elite karate athletes than in the non-athletes in frontal (p<0.00002), central (p<0.008) and right occipital (p<0.02) areas. Similarly, high-frequency alpha TRPD (about 10–12Hz) was lower in the elite karate athletes than in the non-athletes in frontal (p<0.00009) and central (p<0.01) areas. These results suggest that athletes'' brain is characterized by reduced cortical reactivity to eyes opening in the condition of resting state, in line with the “neural efficiency” hypothesis. The present study motivates future research evaluating the extent to which this general functional brain feature is related to heritable trait or intensive visuo-motor training of elite athletes. [Copyright &y& Elsevier]

Abstract: Objective: The “neural efficiency” hypothesis posits that neural activity is reduced in experts. Here we tested the hypothesis that compared with non-athletes, elite athletes are characterized by a reduced cortical activation during simple voluntary movement and that this is reflected by the modulation of dominant alpha rhythms (8–12Hz). Methods: EEG data (56 channels; EB-Neuro) were continuously recorded in the following right-handed subjects: 10 elite karate athletes and 12 non-athletes. During the EEG recordings, they performed brisk voluntary wrist extensions of the right or left hand (right movement and left movement). The EEG cortical sources were estimated by standardized low-resolution brain electromagnetic tomography (sLORETA) freeware. With reference to a baseline period, the power decrease of alpha rhythms during the motor preparation and execution indexed the cortical activation (event-related desynchronization, ERD). Results: During both preparation and execution of the right movements, the low- (about 8–10Hz) and high-frequency alpha ERD (about 10–12Hz) was lower in amplitude in primary motor area, in lateral and medial premotor areas in the elite karate athletes than in the non-athletes. For the left movement, only the high-frequency alpha ERD during the motor execution was lower in the elite karate athletes than in the non-athletes. Conclusions: These results confirmed that compared with non-athletes, elite athletes are characterized by a reduced cortical activation during simple voluntary movement. Significance: Cortical alpha rhythms are implicated in the “neural efficiency” of athletes’ motor systems. [Copyright &y& Elsevier]

Background: Overground Robot-Assisted Gait Training (o-RAGT) appears to be a promising stroke rehabilitation in terms of clinical outcomes. The literature on surface ElectroMyoGraphy (sEMG) assessment in o-RAGT is limited. This paper aimed to assess muscle activation patterns with sEMG in subjects subacute post stroke after training with o-RAGT and conventional therapy. Methods: An observational preliminary study was carried out with subjects subacute post stroke who received 15 sessions of o-RAGT (5 sessions/week; 60 min) in combination with conventional therapy. The subjects were assessed with both clinical and instrumental evaluations. Gait kinematics and sEMG data were acquired before (T1) and after (T2) the period of treatment (during ecological gait), and during the first session of o-RAGT (o-RAGT1). An eight-channel wireless sEMG device acquired in sEMG signals. Significant differences in sEMG outcomes were found in the BS of TA between T1 and T2. There were no other significant correlations between the sEMG outcomes and the clinical results between T1 and T2. Conclusions: There were significant functional gains in gait after complex intensive clinical rehabilitation with o-RAGT and conventional therapy. In addition, there was a significant increase in bilateral symmetry of the Tibialis Anterior muscles. At this stage of the signals from the tibialis anterior (TA), gastrocnemius medialis (GM), rectus femoris (RF), and biceps femoris caput longus (BF) muscles of each lower extremity. sEMG data processing extracted the Bilateral Symmetry (BS), the Co-Contraction (CC), and the Root Mean Square (RMS) coefficients. Results: Eight of 22 subjects in the subacute stage post stroke agreed to participate in this sEMG study. This subsample demonstrated a significant improvement in the motricity index of the affected lower limb and functional ambulation. The heterogeneity of the subjects' characteristics and the small number of subjects was associated with high variability research, functional gait recovery was associated with minimal change in muscle activation patterns. [ABSTRACT FROM AUTHOR]

(1) Background: In neurorehabilitation, Wearable Powered Exoskeletons (WPEs) enable intensive gait training even in individuals who are unable to maintain an upright position. The importance of WPEs is not only related to their impact on walking recovery, but also to the possibility of using them as assistive technology; however, WPE-assisted community ambulation has rarely been studied in terms of walking performance in real-life scenarios. (2) Methods: This study proposes the integration of an Inertial Measurement Unit (IMU) system to analyze gait kinematics during real-life outdoor scenarios (regular, irregular terrains, and slopes) by comparing the ecological gait (no-WPE condition) and WPE-assisted gait in five able-bodied volunteers. The temporal parameters of gait and joint angles were calculated from data collected by a network of seven IMUs. (3) Results: The results showed that the WPE-assisted gait had less knee flexion in the stance phase and greater hip flexion in the swing phase. The different scenarios did not change the human–exoskeleton interaction: only the low-speed WPE-assisted gait was characterized by a longer double support phase. (4) Conclusions: The proposed IMU-based gait assessment protocol enabled quantification of the human–exoskeleton interaction in terms of gait kinematics and paved the way for the study of WPE-assisted community ambulation in stroke patients. [ABSTRACT FROM AUTHOR]

Abstract: Here we tested two working hypotheses on spatially selective cortical activation (“neural efficiency”) in experts: (i) compared to non-athletes, elite karate athletes are characterized by a reduced cortical activation during the judgment of karate actions; (ii) compared to non-athletes and elite karate athletes, amateur karate athletes are characterized by an intermediate cortical activation during the judgment of karate actions. Electroencephalographic (EEG) data were recorded in 16 elite karate athletes, 15 amateur athletes and 17 non-athletes. They observed a series of 120 karate videos. At the end of each video, the subjects had to judge the technical/athletic level of the exercise by a scale from 0 to 10. The mismatch between their judgment and that of the coach indexed the degree of action judgment. The EEG cortical sources were estimated by sLORETA. With reference to a pre-stimulus period, the power decrease of alpha (8–12Hz) rhythms during the video indexed the cortical activation (event-related desynchronization, ERD). Regarding the hypothesis of reduced activity in elite karate athletes, low- and high-frequency alpha ERD was less pronounced in dorsal and “mirror” pathways in the elite karate athletes than in the non-athletes. Regarding the hypothesis of intermediate cortical activity in amateur karate athletes, low- and high-frequency alpha ERD was less pronounced in dorsal pathways across the non-athletes, the amateur karate athletes, and the elite karate athletes. In conclusion, athletes’ judgment of observed sporting actions is related to less pronounced alpha ERD, as a possible index of “neural efficiency” in experts engaged in social cognition. [Copyright &y& Elsevier]

Resting state electroencephalographic (EEG) rhythms reflect the fluctuation of cortical arousal and vigilance in a typical clinical setting, namely the EEG recording for few minutes with eyes closed (i.e., passive condition) and eyes open (i.e., active condition). Can this procedure be back-translated to C57 (wild type) mice for aging studies? On-going EEG rhythms were recorded from a frontoparietal bipolar channel in 85 (19 females) C57 mice. Male mice were subdivided into 3 groups: 25 young (4.5–6 months), 18 middle-aged (12–15 months), and 23 old (20–24 months) mice to test the effect of aging. EEG power density was compared between short periods (about 5 minutes) of awake quiet behavior (passive) and dynamic exploration of the cage (active). Compared with the passive condition, the active condition induced decreased EEG power at 1–2 Hz and increased EEG power at 6–10 Hz in the group of 85 mice. Concerning the aging effects, the passive condition showed higher EEG power at 1–2 Hz in the old group than that in the others. Furthermore, the active condition exhibited a maximum EEG power at 6–8 Hz in the former group and 8–10 Hz in the latter. In the present conditions, delta and theta EEG rhythms reflected changes in cortical arousal and vigilance in freely behaving C57 mice across aging. These changes resemble the so-called slowing of resting state EEG rhythms observed in humans across physiological and pathological aging. The present EEG procedures may be used to enhance preclinical phases of drug discovery in mice for understanding the neurophysiological effects of new compounds against brain aging. [ABSTRACT FROM AUTHOR]

Objective: Resting state electroencephalographic (EEG) rhythms are abnormal in multiple sclerosis (MS) patients, but it is unclear if they can reflect different neurophysiologic abnormalities in MS sub-types (phenotypes) such as relapsing-remitting (RR) and secondary progressive (SP). Methods: We tested whether cortical sources of resting state EEG rhythms are abnormal in MS patients and differ between MS phenotypes. Resting state eyes-closed EEG activity was recorded in 36 RR, 23 SP, and 41 matched healthy subjects. EEG bands of interest were individually identified based on Transition frequency (TF), Individual alpha frequency (IAF), and Individual beta frequency (IBF). LORETA freeware estimated cortical EEG sources. Results: Widespread TF -4 Hz (delta) and IAF (alpha) cortical sources were abnormal in the MS sub-groups compared to the control group. Furthermore, TF 4 Hz sources in central, parietal, and limbic regions were higher in amplitude in the SP compared to the RR sub-group. Conclusion: Cortical sources of resting state EEG rhythms are abnormal in MS patients at group level and differ between RR and SP sub-groups. Significance: Future studies should test the utility of these EEG markers in the diagnosis and management of MS clinical phenotypes and in the therapy evaluation. [ABSTRACT FROM AUTHOR]

Background: Assistive and robotic training devices are increasingly used for rehabilitation of the hemiparetic arm after stroke, although applications for the wrist and hand are trailing behind. Furthermore, applying a training device in domestic settings may enable an increased training dose of functional arm and hand training. The objective of this study was to assess the feasibility and potential clinical changes associated with a technology-supported arm and hand training system at home for patients with chronic stroke. Methods: A dynamic wrist and hand orthosis was combined with a remotely monitored user interface with motivational gaming environment for self-administered training at home. Twenty-four chronic stroke patients with impaired arm/hand function were recruited to use the training system at home for six weeks. Evaluation of feasibility involved training duration, usability and motivation. Clinical outcomes on arm/hand function, activity and participation were assessed before and after six weeks of training and at two-month follow-up. Results: Mean System Usability Scale score was 69 % (SD 17 %), mean Intrinsic Motivation Inventory score was 5.2 (SD 0.9) points, and mean training duration per week was 105 (SD 66) minutes. Median Fugl-Meyer score improved from 37 (IQR 30) pre-training to 41 (IQR 32) post-training and was sustained at two-month follow-up (40 (IQR 32)). The Stroke Impact Scale improved from 56.3 (SD 13.2) pre-training to 60.0 (SD 13.9) post-training, with a trend at follow-up (59.8 (SD 15.2)). No significant improvements were found on the Action Research Arm Test and Motor Activity Log. Conclusions: Remotely monitored post-stroke training at home applying gaming exercises while physically supporting the wrist and hand showed to be feasible: participants were able and motivated to use the training system independently at home. Usability shows potential, although several usability issues need further attention. Upper extremity function and quality of life improved after training, although dexterity did not. These findings indicate that home-based arm and hand training with physical support from a dynamic orthosis is a feasible tool to enable self-administered practice at home. Such an approach enables practice without dependence on therapist availability, allowing an increase in training dose with respect to treatment in supervised settings. Trial Registration: This study has been registered at the Netherlands Trial Registry (NTR): NTR3669 . [ABSTRACT FROM AUTHOR]

Background: Assistive and robotic training devices are increasingly used for rehabilitation of the hemiparetic arm after stroke, although applications for the wrist and hand are trailing behind. Furthermore, applying a training device in domestic settings may enable an increased training dose of functional arm and hand training. The objective of this study was to assess the feasibility and potential clinical changes associated with a technology-supported arm and hand training system at home for patients with chronic stroke. Methods: A dynamic wrist and hand orthosis was combined with a remotely monitored user interface with motivational gaming environment for self-administered training at home. Twenty-four chronic stroke patients with impaired arm/hand function were recruited to use the training system at home for six weeks. Evaluation of feasibility involved training duration, usability and motivation. Clinical outcomes on arm/hand function, activity and participation were assessed before and after six weeks of training and at two-month follow-up. Results: Mean System Usability Scale score was 69 % (SD 17 %), mean Intrinsic Motivation Inventory score was 5.2 (SD 0.9) points, and mean training duration per week was 105 (SD 66) minutes. Median Fugl-Meyer score improved from 37 (IQR 30) pre-training to 41 (IQR 32) post-training and was sustained at two-month follow-up (40 (IQR 32)). The Stroke Impact Scale improved from 56.3 (SD 13.2) pre-training to 60.0 (SD 13.9) post-training, with a trend at follow-up (59.8 (SD 15.2)). No significant improvements were found on the Action Research Arm Test and Motor Activity Log. Conclusions: Remotely monitored post-stroke training at home applying gaming exercises while physically supporting the wrist and hand showed to be feasible: participants were able and motivated to use the training system independently at home. Usability shows potential, although several usability issues need further attention. Upper extremity function and quality of life improved after training, although dexterity did not. These findings indicate that home-based arm and hand training with physical support from a dynamic orthosis is a feasible tool to enable self-administered practice at home. Such an approach enables practice without dependence on therapist availability, allowing an increase in training dose with respect to treatment in supervised settings. [ABSTRACT FROM AUTHOR]

Abstract: Cortical sources of resting state electroencephalographic (EEG) rhythms are abnormal in subjects with mild cognitive impairment (MCI). Here, we tested the hypothesis that these sources in amnesic MCI subjects further deteriorate over 1 year. To this aim, the resting state eyes-closed EEG data were recorded in 54 MCI subjects at baseline (Mini Mental State Examination I = 26.9; standard error [SE], 0.2) and at approximately 1-year follow-up (13.8 months; SE, 0.5; Mini Mental State Examination II = 25.8; SE, 0.2). As a control, EEG recordings were also performed in 45 normal elderly and in 50 mild Alzheimer's disease subjects. EEG rhythms of interest were delta (2–4 Hz), theta (4–8 Hz), alpha1 (8–10.5 Hz), alpha2 (10.5–13 Hz), beta1 (13–20 Hz), and beta2 (20–30 Hz). Cortical EEG sources were estimated using low-resolution brain electromagnetic tomography. Compared with the normal elderly and mild Alzheimer's disease subjects, the MCI subjects were characterized by an intermediate power of posterior alpha1 sources. In the MCI subjects, the follow-up EEG recordings showed a decreased power of posterior alpha1 and alpha2 sources. These results suggest that the resting state EEG alpha sources were sensitive—at least at the group level—to the cognitive decline occurring in the amnesic MCI group over 1 year, and might represent cost-effective, noninvasive and widely available markers to follow amnesic MCI populations in large clinical trials. [Copyright &y& Elsevier]

Abstract: Objective: Obese subjects without eating disorders were characterised by poor electroencephalographic (EEG) alpha rhythms during resting-state eye-closed condition (Babiloni et al., 2011b). Is this true also for the desynchronisation of alpha rhythms during resting-state eyes opening? Methods: EEG data were recorded in 15 underweight, 20 normal-weight, and 18 overweight/obese subjects during resting-state eyes-closed and -open conditions. EEG sources were estimated by LORETA for alpha 1 (8–10.5Hz) and alpha 2 (10.5–13Hz). The alpha desynchronisation was calculated as the difference eyes-open minus -closed condition. Results: The occipital alpha 1 desynchronisation was lower in overweight/obese and underweight subjects compared with normal-weight subjects (p <0.000005). The same was true for parietal, occipital and temporal alpha 2 (10.5–13Hz) desynchronisation (p <0.000002). The parietal and temporal alpha 1 desynchronisation was lower in overweight/obese than in normal-weight subjects (p <0.00001). These effects spatially matched those observed in the resting-state eyes-closed condition. Conclusion: Subjects with abnormal weight and normal eating behaviour are characterised by poor alpha desynchronisation during resting-state eyes opening. Significance: Obese subjects without eating disorders show abnormal mechanisms of cortical neural synchronisation and desynchronisation of alpha rhythms in the resting state condition. [Copyright &y& Elsevier]

Abstract: Acetylcholinesterase inhibitors (AChEIs) are the most widely used symptomatic treatment for mild to severe Alzheimer’s disease (AD) patients, while N-methyl-d-aspartic acid (NMDA) receptor antagonist memantine is licensed for use in moderate to severe AD patients. In this article, the effect of these compounds on resting state eyes-closed electroencephalographic (EEG) rhythms in AD patients is reviewed to form a knowledge platform for the European Innovative Medicine Initiative project “PharmaCog” (IMI Grant Agreement No. 115009) aimed at developing innovative translational models for drug testing in AD. Indeed, quite similar EEG experiments and the same kind of spectral data analysis can be performed in animal models of AD and in elderly individuals with prodromal or manifest AD. Several studies have shown that AChEIs affect both resting state EEG rhythms and cognitive functions in AD patients. After few weeks of successful treatment, delta (0–3Hz) or theta (4–7Hz) rhythms decrease, dominant alpha rhythms (8–10Hz) increase, and cognitive functions slightly improve. Beneficial effects of these rhythms and cognitive functions were also found in AD responders to the long-term successful treatment (i.e. 6–12months). In contrast, only one study has explored the long-term effects of memantine on EEG rhythms in AD patients, showing reduced theta rhythms. The present review enlightens the expected effects of AChEIs on resting state EEG rhythms in AD patients as promising EEG markers for the development of translational protocols both within the PharmaCog project and for wider use. [Copyright &y& Elsevier]

Abstract: Objective: The IZOF-based probabilistic approach provides a methodology to study within-individual patterns of a performer''s states. So far, the time course of physiological data before performance have not been investigated within the probabilistic methodology framework. The purpose of this study was to examine the value of the probabilistic approach in the assessment of the time course of physiological indicators of arousal/activation and vigilance during the period preceding the shot, in comparison with the performance-based method. Design: Longitudinal assessment of psycho-physiological data and performance outcomes was conducted on eight elite pistol shooters in a controlled setting. Methods: Each participant performed 60 air-pistol shots in 2 sessions. Skin conductance level and cardiac activity were recorded. Affective states intensity was evaluated on a modified 11-point Borg scale. Affect, HR and SC level were evaluated with a Performance-based approach and a Probabilistic method, and results compared at an individual level. Results: Findings showed the higher effectiveness of the probabilistic method to analyse physiological parameters (skin conductance and heart rate) and to describe the physiological mechanisms associated with shooters’ performance. Conclusions: The probabilistic method better discerned the contribution of arousal/activation and vigilance to optimal and non-optimal performance in elite shooters, thereby providing a sharper representation of the temporal pattern of performers'' states before shooting. From an applied perspective, we believe that the probabilistic approach can help athletes become aware of the subtle variations occurring in their psychophysical states during the preparatory period preceding the shot and not only at the moment of shot release. [Copyright &y& Elsevier]

Abstract: The present electroencephalographic (EEG) study tested the working hypothesis that the amplitude of resting state cortical EEG rhythms (especially alpha, 8–12Hz) was higher in elite athletes compared with amateur athletes and non-athletes, as a reflection of the efficiency of underlying back-ground neural synchronization mechanisms. Eyes closed resting state EEG data were recorded in 16 elite karate athletes, 20 amateur karate athletes, and 25 non-athletes. The EEG rhythms of interest were delta (2–4Hz), theta (4–8Hz), alpha 1 (8–10.5Hz), alpha 2 (10.5–13Hz), beta 1 (13–20Hz), and beta 2 (20–30Hz). EEG cortical sources were estimated by low-resolution brain electromagnetic tomography (LORETA). Statistical results showed that the amplitude of parietal and occipital alpha 1 sources was significantly higher in the elite karate athletes than in the non-athletes and karate amateur athletes. Similar results were observed in parietal and occipital delta sources as well as in occipital theta sources. Finally, a control confirmatory experiment showed that the amplitude of parietal and occipital delta and alpha 1 sources was stronger in 8 elite rhythmic gymnasts compared with 14 non-athletes. These results supported the hypothesis that cortical neural synchronization at the basis of eyes-closed resting state EEG rhythms is enhanced in elite athletes than in control subjects. [Copyright &y& Elsevier]

This study tested the two following hypotheses: (i) compared with non-athletes, elite athletes are characterized by a reduced cortical activation during the preparation of precise visuo-motor performance; (ii) in elite athletes, an optimal visuo-motor performance is related to a low cortical activation. To this aim, electroencephalographic (EEG; 56 channels; Be Plus EB-Neuro) data were recorded in 18 right-handed elite air pistol shooters and 10 right-handed non-athletes. All subjects performed 120 shots. The EEG data were spatially enhanced by surface Laplacian estimation. With reference to a baseline period, power decrease/increase of alpha rhythms during the preshot period indexed the cortical activation/deactivation (event-related desynchronization/synchronization, ERD/ERS). Regarding the hypothesis (i), low- (about 8-10 Hz) and high-frequency (about 10-12 Hz) alpha ERD was lower in amplitude in the elite athletes than in the non-athletes over the whole scalp. Regarding the hypothesis (ii), the elite athletes showed high-frequency alpha ERS (about 10-12 Hz) larger in amplitude for high score shots (50%) than for low score shots; this was true in right parietal and left central areas. A control analysis confirmed these results with another indicator of cortical activation (beta ERD, about 20 Hz). The control analysis also showed that the amplitude reduction of alpha ERD for the high compared with low score shots was not observed in the non-athletes. The present findings globally suggest that in elite athletes (experts), visuo-motor performance is related to a global decrease of cortical activity, as a possible index of spatially selective cortical processes ('neural efficiency'). Hum Brain Mapp, 2009. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Abstract: “Neural efficiency” hypothesis posits that neural activity is reduced in experts. Here we tested the hypothesis that compared with non-athletes, elite athletes are characterized by a reduction of cortical activation during an engaging upright standing. EEG (56 channels; Be-plus Eb-Neuro©) and stabilogram (RGM©) data were simultaneously recorded in 10 elite karate, 10 elite fencing athletes, and 12 non-athletes during a simple bipodalic (standard Romberg) and a more engaging monopodalic upright standing. Balance was indexed by body “sway area”. The EEG data were spatially enhanced by surface Laplacian estimation. Cortical activity was indexed by task-related power decrease (TRPD) of EEG alpha power (8–12Hz) during monopodalic referenced to bipodalic condition. The body “sway area” was larger during the monopodalic than bipodalic upright standing in all groups. Low-frequency alpha TRPD (about 8–10Hz) was lower in amplitude in the karate and fencing athletes than in the non-athletes at left central, right central, middle parietal, and right parietal areas (p <0.01). Similarly, the amplitude of high-frequency alpha TRPD (10–12Hz) was lower in the karate and fencing athletes than in the non-athletes at right frontal, left central, right central, and middle parietal areas (p <0.03). These results suggest that during monopodalic referenced to less engaging bipodalic condition, the power decrease (i.e. the desynchronization) of cortical activity at alpha rhythms is largely reduced in elite athletes than in non-athletes, in line with the “neural efficiency” hypothesis. The present study extends our understanding of the physiological mechanisms at the basis of the “neural efficiency” for engaging upright standing in elite athletes. [Copyright &y& Elsevier]

Abstract: The present study tested the two following hypotheses: (i) compared to non-athletes, elite athletes are characterized by a reduced cortical activation during the judgment of sporting observed actions; (ii) in elite athletes, a good judgment of observed sporting actions is related to a low cortical activation. To address these issues, electroencephalographic (EEG) data were recorded in 15 elite rhythmic gymnasts and 13 non-gymnasts. They observed a series of 120 rhythmic gymnastic videos. At the end of each video, the subjects had to judge the artistic/athletic level of the exercise by a scale from 0 to 10. The mismatch between their judgment and that of the coach indexed the degree of action judgment. The EEG cortical sources were estimated by sLORETA. With reference to a pre-stimulus period, the power decrease of alpha (8–12 Hz) rhythms during the videos indexed the cortical activation (event related desynchronization, ERD). Regarding the hypothesis (i), low- and high-frequency alpha ERD was lower in amplitude in the elite rhythmic gymnasts compared to the non-gymnasts in occipital and temporal areas (ventral pathway) and in dorsal pathway. Regarding the hypothesis (ii), in the elite rhythmic gymnasts high-frequency alpha ERD was higher in amplitude with the videos characterized by a high judgment error than those characterized by a low judgment error; this was true in inferior posterior parietal and ventral premotor areas (“mirror” pathway). These results globally suggest that the judgment of observed sporting actions is related to low amplitude of alpha ERD, as a possible index of spatially selective cortical activation (“neural efficiency”). [Copyright &y& Elsevier]

Abstract: The present electroencephalographic (EEG) study evaluated the hypothesis of a preferred directionality of communication flows between brain hemispheres across 24h (i.e., during the whole daytime and nighttime), as an extension of a recent report showing changes in preferred directionality from pre-sleep wake to early sleep stages. Scalp EEGs were recorded in 10 normal volunteers during daytime wakefulness (eyes closed; first period: from 10:00 to 13:00h; second period: from 14:00 to 18:00h; third period: from 19:00 to 22:00h) and nighttime sleep (four NREM-REM cycles). EEG rhythms of interest were delta (1–4Hz), theta (5–7Hz), alpha (8–11Hz), sigma (12–15Hz) and beta (16–28Hz). The direction of the inter-hemispheric information flow was evaluated by computing the directed transfer function (DTF) from these EEG rhythms. Inter-hemispheric directional flows varied as a function of the state of consciousness (wake, NREM sleep, REM sleep) and in relation to different cerebral areas. During the daytime, alpha and beta rhythms conveyed inter-hemispheric signals with preferred Left-to-Right hemisphere direction in parietal and central areas, respectively. During the NREM sleep periods of nighttime, the direction of inter-hemispheric DTF information flows conveyed by central beta rhythms was again preponderant from Left-to-Right hemisphere in the stage 2, independent of cortical areas. No preferred direction emerged across the REM periods. These results support the hypothesis that specific directionality of communication flows between brain hemispheres is associated with wakefulness, NREM (particularly stage 2) and REM states during daytime and nighttime. They also reinforce the suggestive hypothesis of a relationship between inter-hemispheric directionality of EEG functional coupling and frequency of the EEG rhythms. [Copyright &y& Elsevier]

Abstract: Is directionality of electroencephalographic (EEG) synchronization abnormal in amnesic mild cognitive impairment (MCI) and Alzheimer''s disease (AD)? EEG data were recorded in 64 normal elderly (Nold), 69 amnesic MCI, and 73 mild AD subjects at rest condition (closed eyes). Direction of information flux within EEG functional coupling at electrode pairs was performed by directed transfer function (DTF) at delta (2–4Hz), theta (4–8Hz), alpha 1 (8–10Hz), alpha 2 (10–12Hz), beta 1 (13–20Hz), beta 2 (20–30Hz), and gamma (30–40Hz). Parietal to frontal direction of the information flux within EEG functional coupling was stronger in Nold than in MCI and/or AD subjects, namely for alpha and beta rhythms. In contrast, the directional flow within inter-hemispheric EEG functional coupling did not discriminate among the three groups. These results suggest that directionality of parieto-to-frontal EEG synchronization is abnormal not only in AD but also in amnesic MCI. [Copyright &y& Elsevier]

Do cerebrovascular and Alzheimer's disease (AD) lesions represent additive factors in the development of mild cognitive impairment (MCI) as a putative preclinical stage of AD? Here we tested the hypothesis that directionality of fronto-parietal functional coupling of electroencephalographic (EEG) rhythms is relatively preserved in amnesic MCI subjects in whom the cognitive decline is mainly explained by white-matter vascular load. Resting EEG was recorded in 40 healthy elderly (Nold) and 78 amnesic MCI. In the MCI subjects, white-matter vascular load was quantified based on magnetic resonance images (0-30 visual rating scale). EEG rhythms of interest were δ (2-4 Hz), θ (4-8 Hz), α1 (8-10.5 Hz), α2 (10.5-13 Hz), β1 (13-20 Hz), and β2 (20-30 Hz). Directionality of fronto-parietal functional coupling of EEG rhythms was estimated by directed transfer function software. As main results, (i) fronto-parietal functional coupling of EEG rhythms was higher in magnitude in the Nold than in the MCI subjects; (ii) more interestingly, that coupling was higher at θ, α1, α2, and β1 in MCI V+ (high vascular load; N = 42; MMSE = 26) than in MCI V− group (low vascular load; N = 36; MMSE= 26.7). These results are interpreted as supporting the additive model according to which MCI state would result from the combination of cerebrovascular and neurodegenerative lesions. Hum Brain Mapp 2008. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Abstract: “Neural efficiency” hypothesis posits that cortical activity is spatially focused in experts. Here we tested the hypothesis that compared to non-athletes, elite athletes are characterized by a reduced cortical activation during visuo-motor tasks related to the field of expertise, as a function of movement side. EEG data (56 channels; EB-Neuro) were continuously recorded in the following right-handed subjects: 11 non-athletes, 11 elite fencing athletes, and 11 elite karate athletes. During the EEG recordings, they observed pictures with fencing and karate attacks, and had to quickly click a right (left) keyboard button for the attacks at right (left) monitor side. The EEG data were averaged with respect to the movement onset, and were spatially enhanced by surface Laplacian estimation. The potentials related to the preparation (readiness potential) and initiation (motor potential) of the movements were measured. For the right movement, the potentials overlying supplementary motor and contralateral sensorimotor areas were higher in amplitude in the non-athletes than in the elite karate and fencing athletes. Furthermore, the amplitude of the motor potential over ipsilateral sensorimotor area was higher in the elite karate than fencing athletes, and its distribution over bilateral sensorimotor areas was less asymmetrical in the karate than in the other two groups. For the left movement, these potentials showed no difference between the groups. The present results suggest that “neural efficiency” hypothesis does not fully account for the organization of motor systems in elite athletes. “Neural efficiency” would depend on several factors including side of the movement, hemisphere, and kind of athletes. [Copyright &y& Elsevier]

It is not known whether frontal cerebral rhythms of the two hemispheres are implicated in fine motor control and balance. To address this issue, electroencephalographic (EEG) and stabilometric recordings were simultaneously performed in 12 right-handed expert golfers. The subjects were asked to stand upright on a stabilometric force platform placed at a golf green simulator while playing about 100 golf putts. Balance during the putts was indexed by body sway area. Cortical activity was indexed by the power reduction in spatially enhanced alpha (8–12 Hz) and beta (13–30 Hz) rhythms during movement, referred to as the pre-movement period. It was found that the body sway area displayed similar values in the successful and unsuccessful putts. In contrast, the high-frequency alpha power (about 10–12 Hz) was smaller in amplitude in the successful than in the unsuccessful putts over the frontal midline and the arm and hand region of the right primary sensorimotor area; the stronger the reduction of the alpha power, the smaller the error of the unsuccessful putts (i.e. distance from the hole). These results indicate that high-frequency alpha rhythms over associative, premotor and non-dominant primary sensorimotor areas subserve motor control and are predictive of the golfer's performance. [ABSTRACT FROM AUTHOR]

In rehabilitation, the upper limb function is generally assessed using clinical scales and functional motor tests. Although the Box and Block Test (BBT) is commonly used for its simplicity and ease of execution, it does not provide a quantitative measure of movement quality. This study proposes the integration of an ecological Inertial Measurement Units (IMUs) system for analysis of the upper body kinematics during the execution of a targeted version of BBT, by able-bodied persons with subjects with Parkinson's disease (PD). Joint angle parameters (mean angle and range of execution) and hand trajectory kinematic indices (mean velocity, mean acceleration, and dimensionless jerk) were calculated from the data acquired by a network of seven IMUs. The sensors were applied on the trunk, head, and upper limb in order to characterize the motor strategy used during the execution of BBT. Statistics revealed significant differences (p < 0.05) between the two groups, showing compensatory strategies in subjects with PD. The proposed IMU-based targeted BBT protocol allows to assess the upper limb function during manual dexterity tasks and could be used in the future for assessing the efficacy of rehabilitative treatments. [ABSTRACT FROM AUTHOR]

Problem identification Purpose of our research is the development and testing of procedures for the study of functional brain organization in elite athletes and patients with cerebral neurodegenerative processes to test “neural efficiency” hypothesis (i.e. selective cortical activity in experts). Methodology Cortical activity in elite athletes and patients with Alzheimer‘s disease (AD) was indexed by the study of electroencephalographic (EEG) oscillations in the resting state condition and during events. Results ATHLETES ( Del Percio et al., 2008, 2009, 2010; Babiloni et al., 2009, 2010 ). More resting state eyes-closed posterior cortical alpha (8–12 Hz) power was observed in elite athletes than in amateur athletes and non-athletes, thus suggesting that athletes’ brain is more inhibited in this condition. Furthermore, there was a reduced event-related alpha desynchronization as a sign of less cortical activation in elite athletes than in amateur athletes and non-athletes, during both cognitive and motor events, with some exceptions to be better understood. AD PATIENTS ( Babiloni et al., 2004, 2007, 2010, 2013 ). Less resting state eyes-closed posterior cortical alpha (8–10 Hz) power was observed in prodromic and overt AD than in normal elderly subjects, thus suggesting that patients’ brain is less inhibited in this condition. Furthermore, there was a reduced event-related alpha desynchronization as a sign of less cortical activation in the former than in the latter ones during eyes opening. Conclusions “Neural efficiency” as a sign of more selectivity and inhibitory capability of brain oscillatory processes may explain at least in part high cognitive-motor performance in athletes and some cognitive-motor abnormalities in AD patients. Keywords EEG; Cognitive-motor processes; Elite athletes [ABSTRACT FROM AUTHOR]