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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., (Copyright © 2016 Elsevier Inc. All rights reserved.)

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 -4Hz (delta) and IAF (alpha) cortical sources were abnormal in the MS sub-groups compared to the control group. Furthermore, TF -4Hz 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., (Copyright © 2015 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

Stroke is the leading cause of permanent disability in developed countries; its effects may include sensory, motor, and cognitive impairment as well as a reduced ability to perform self-care and participate in social and community activities. A number of studies have shown that the use of robotic systems in upper limb motor rehabilitation programs provides safe and intensive treatment to patients with motor impairments because of a neurological injury. Furthermore, robot-aided therapy was shown to be well accepted and tolerated by all patients; however, it is not known whether a specific robot-aided rehabilitation can induce beneficial cortical plasticity in stroke patients. Here, we present a procedure to study neural underpinning of robot-aided upper limb rehabilitation in stroke patients. Neurophysiological recordings use the following: (a) 10-20 system electroencephalographic (EEG) electrode montage; (b) bipolar vertical and horizontal electrooculographies; and (c) bipolar electromyography from the operating upper limb. Behavior monitoring includes the following: (a) clinical data and (b) kinematic and dynamic of the operant upper limb movements. Experimental conditions include the following: (a) resting state eyes closed and eyes open, and (b) robotic rehabilitation task (maximum 80 s each block to reach 4-min EEG data; interblock pause of 1 min). The data collection is performed before and after a program of 30 daily rehabilitation sessions. EEG markers include the following: (a) EEG power density in the eyes-closed condition; (b) reactivity of EEG power density to eyes opening; and (c) reactivity of EEG power density to robotic rehabilitation task. The above procedure was tested on a subacute patient (29 poststroke days) and on a chronic patient (21 poststroke months). After the rehabilitation program, we observed (a) improved clinical condition; (b) improved performance during the robotic task; (c) reduced delta rhythms (1-4 Hz) and increased alpha rhythms (8-12 Hz) during the resting state eyes-closed condition; (d) increased alpha desynchronization to eyes opening; and (e) decreased alpha desynchronization during the robotic rehabilitation task. We conclude that the present procedure is suitable for evaluation of the neural underpinning of robot-aided upper limb rehabilitation.

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 © 2014 Elsevier Inc. All rights reserved.)

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 (8-10.5 Hz) and alpha 2 (10.5-13 Hz). 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 (10.5-13 Hz) 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 © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

Here we describe a methodological approach for the simultaneous electroencephalographic (EEG) recording in musicians playing in ensemble. Four professional saxophonists wore pre-wired EEG caps (30 electrodes placed according to an augmented 10-20 system; cephalic reference and ground). Each cap was connected to a single multi-channel amplifier box [Brain Explorer (BE), EB-Neuro(©)]. The four boxes converged to a single workstation equipped with a software (GALILEO NT, EB-Neuro(©)) allowing the simultaneous recording of sounds, digital trigger, and EEG-electrooculographic (EOG)-electromyographic (EMG) data, and providing a separate output file for each individual. Noteworthy, the subjects were electrically decoupled to satisfy international safety guidelines. The quality of the EEG data was confirmed by the rate of artifact-free EEG epochs (about 80%) and by EEG spectral features. During the resting state, dominant EEG power density values were observed at alpha band (8-12Hz) in posterior cortex. The quality of EMG can be used to identify "on" and "off" states of the musicians' motor performance, thus potentially allowing the investigation of the relationships between EEG dynamics and different characteristics of the specific performance. During the music performance, alpha power density values decreased in amplitude in several cortical regions, whereas power density values enhanced within narrow high-frequency bands. In conclusion, the present methodological approach appeared to be suitable for simultaneous EEG recordings in musicians playing in ensemble., (Copyright © 2011 Elsevier Srl. All rights reserved.)

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 (8-12 Hz)., 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 8-10 Hz) and high-frequency alpha ERD (about 10-12 Hz) 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., (2009 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

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").