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A. Oliviero

Bio: A. Oliviero is an academic researcher from Catholic University of the Sacred Heart. The author has contributed to research in topics: Medicine & Chemistry. The author has an hindex of 27, co-authored 33 publications receiving 10329 citations.


Papers
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Journal ArticleDOI
TL;DR: There is a sufficient body of evidence to accept with level A (definite efficacy) the analgesic effect of high-frequency rTMS of the primary motor cortex (M1) contralateral to the pain and the antidepressant effect of HF-rT MS of the left dorsolateral prefrontal cortex (DLPFC).

1,554 citations

Journal ArticleDOI
TL;DR: Local potentials from the globus pallidus interna and subthalamic nucleus are recorded in four awake patients after neurosurgery for Parkinson's disease to demonstrate synchronization of activity does occur between pallidum and STN, and its pattern is critically dependent on the level of dopaminergic activity.
Abstract: The extent of synchronization within and between the nuclei of the basal ganglia is unknown in Parkinson's disease. The question is an important one because synchronization will increase postsynaptic efficacy at subsequent projection targets. We simultaneously recorded local potentials (LPs) from the globus pallidus interna (GPi) and subthalamic nucleus (STN) in four awake patients after neurosurgery for Parkinson's disease. Nuclei from both sides were recorded in two patients so that a total of six ipsilateral GPi–STN LP recordings were made. Without medication, the power within and the coherence between the GPi and STN was dominated by activity with a frequency <30 Hz. Treatment with the dopamine precursor levodopa reduced the low-frequency activity and resulted in a new peak at ∼70 Hz. This was evident in the power spectrum from STN and GPi and in the coherence between these nuclei. The phase relationship between the nuclei varied in a complex manner according to frequency band and the presence of exogenous dopaminergic stimulation. Synchronization of activity does occur between pallidum and STN, and its pattern is critically dependent on the level of dopaminergic activity.

1,064 citations

Journal ArticleDOI
TL;DR: These guidelines cover practical aspects of TMS in a clinical setting and lay out the general principles that apply to a standardized clinical examination of the fast-conducting corticomotor pathways with single-pulse TMS.

901 citations

Journal ArticleDOI
TL;DR: These updated recommendations take into account all rTMS publications, including data prior to 2014, as well as currently reviewed literature until the end of 2018, and are based on the differences reached in therapeutic efficacy of real vs. sham rT MS protocols.

822 citations

Journal ArticleDOI
TL;DR: It is concluded that mixed or cutaneous input from the hand can suppress the excitability of the motor cortex at short latency, which may contribute to the initial inhibition of the cutaneomuscular reflex.
Abstract: EMG responses evoked in hand muscles by transcranial stimulation over the motor cortex were conditioned by a single motor threshold electrical stimulus to the median nerve at the wrist in a total of ten healthy subjects and in five patients who had electrodes implanted chronically into the cervical epidural space. The median nerve stimulus suppressed responses evoked by transcranial magnetic stimulation (TMS) in relaxed or active muscle. The minimum interval between the stimuli at which this occurred was 19 ms. A similar effect was seen if electrical stimulation was applied to the digital nerves of the first two fingers. Median or digital nerve stimulation could suppress the responses evoked in active muscle by transcranial electrical stimulation over the motor cortex, but the effect was much less than with magnetic stimulation. During contraction without TMS, both types of conditioning stimuli evoked a cutaneomuscular reflex that began with a short period of inhibition. This started about 5 ms after the inhibition of responses evoked by TMS. Recordings in the patients showed that median nerve stimulation reduced the size and number of descending corticospinal volleys evoked by magnetic stimulation. We conclude that mixed or cutaneous input from the hand can suppress the excitability of the motor cortex at short latency. This suppression may contribute to the initial inhibition of the cutaneomuscular reflex. Reduced spinal excitability in this period could account for the mild inhibition of responses to electrical brain stimulation. Several groups have used transcranial magnetic stimulation (TMS) to test how the excitability of the motor cortex is affected by afferent input. Much of the initial work was concerned with testing the concept of excitatory transcortical reflexes. These reflexes are readily obtained in hand muscles after electrical or natural stimulation of cutaneous and/or muscle afferents and have a variety of names, such as LLR II/III, E2, V2, M2 and long-latency stretch reflex (Caccia et al. 1973; Marsden et al. 1976; Jenner & Stephens, 1982; Deuschl et al. 1985). Data from neurological patients very strongly suggests that many of these responses are produced by activity in a transcortical reflex pathway that operates in parallel with spinal systems (Marsden et al. 1977a,b; Jenner & Stephens, 1982; Noth et al. 1985). Experiments with transcranial stimulation gave results that were consistent with this idea. They showed that stimuli capable of eliciting long latency reflexes also increased the excitability of the motor cortex to transcranial magnetic stimulation with a time course consistent with traffic in a transcortical loop (Day et al. 1991). In contrast with these reports, some studies have indicated that peripheral input can suppress the excitability of motor cortex. In a short note, Delwaide & Olivier (1990) reported that stimulation of the median nerve at the wrist could profoundly suppress EMG responses evoked in relaxed hand muscles by transcranial magnetic stimulation of the cortex 18–21 ms later. Similar effects could be seen after stimulation of the cutaneous nerves of the index finger. Since H-reflexes in forearm muscles were unaffected Delwaide & Olivier (1990) suggested that the effect occurred at the cortical rather than the spinal level. Maertens de Noordhout et al. (1992) investigated the sequence of excitatory and inhibitory reflexes (Caccia et al. 1973) in the first dorsal interosseous muscle evoked by electrical stimulation of digital nerves. They used transcranial magnetic and electrical stimulation to show that motor cortical excitability was reduced by electrical stimulation of the digital nerves at a time corresponding to the transition between the initial inhibition and subsequent facilitation of the cutaneomuscular reflex. Palmer & Ashby (1992) reported the same result. Most recently, Bertolasi et al. (1998) found that stimulation of probable muscle afferents in the median nerve could suppress the excitability of cortical projections to forearm extensor muscles whilst radial stimulation suppressed the excitability of cortical projections to forearm flexor muscles. Stimulation of cutaneous afferents in digital nerves failed to have any effect. They suggested that the effect from muscle afferents was a cortical analogue of spinal reciprocal inhibition. The purpose of the present experiments was to extend the original observations of Delwaide & Olivier (1990). They confirm the presence of this early, striking period of inhibition, and show that it is a cortical phenomenon. We also speculate that it is related to and may even be responsible for the initial period of inhibition evident in cutaneo-muscular reflexes of the hand.

681 citations


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Journal ArticleDOI
TL;DR: Evidence for "central" fatigue and the neural mechanisms underlying it are reviewed, together with its terminology and the methods used to reveal it.
Abstract: Muscle fatigue is an exercise-induced reduction in maximal voluntary muscle force. It may arise not only because of peripheral changes at the level of the muscle, but also because the central nervous system fails to drive the motoneurons adequately. Evidence for “central” fatigue and the neural mechanisms underlying it are reviewed, together with its terminology and the methods used to reveal it. Much data suggest that voluntary activation of human motoneurons and muscle fibers is suboptimal and thus maximal voluntary force is commonly less than true maximal force. Hence, maximal voluntary strength can often be below true maximal muscle force. The technique of twitch interpolation has helped to reveal the changes in drive to motoneurons during fatigue. Voluntary activation usually diminishes during maximal voluntary isometric tasks, that is central fatigue develops, and motor unit firing rates decline. Transcranial magnetic stimulation over the motor cortex during fatiguing exercise has revealed focal cha...

3,200 citations

Journal ArticleDOI
04 Jun 2009-Nature
TL;DR: The timing of a sensory input relative to a gamma cycle determined the amplitude and precision of evoked responses and provided the first causal evidence that distinct network activity states can be induced in vivo by cell-type-specific activation.
Abstract: Corticalgammaoscillations(20280Hz)predictincreasesinfocusedattention,andfailureingammaregulationisahallmark of neurological and psychiatric disease. Current theory predicts that gamma oscillations are generated by synchronous activity of fast-spiking inhibitory interneurons, with the resulting rhythmic inhibition producing neural ensemble synchrony by generating a narrow window for effective excitation. We causally tested these hypotheses in barrel cortex in vivo by targeting optogenetic manipulation selectively to fast-spiking interneurons. Here we show that light-driven activation of fast-spiking interneurons atvariedfrequencies (82200Hz) selectivelyamplifies gamma oscillations. Incontrast, pyramidal neuron activation amplifies only lower frequency oscillations, a cell-type-specific double dissociation. We found that the timing of a sensory input relative to a gamma cycle determined the amplitude and precision of evoked responses. Our data directly support the fast-spiking-gamma hypothesis and provide the first causal evidence that distinct network activity states can be induced in vivo by cell-type-specific activation.

2,453 citations

Journal ArticleDOI
TL;DR: Efficiency was reduced disproportionately to cost in older people, and the detrimental effects of age on efficiency were localised to frontal and temporal cortical and subcortical regions.
Abstract: Brain anatomical networks are sparse, complex, and have economical small-world properties. We investigated the efficiency and cost of human brain functional networks measured using functional magnetic resonance imaging (fMRI) in a factorial design: two groups of healthy old (N = 11; mean age = 66.5 years) and healthy young (N = 15; mean age = 24.7 years) volunteers were each scanned twice in a no-task or “resting” state following placebo or a single dose of a dopamine receptor antagonist (sulpiride 400 mg). Functional connectivity between 90 cortical and subcortical regions was estimated by wavelet correlation analysis, in the frequency interval 0.06–0.11 Hz, and thresholded to construct undirected graphs. These brain functional networks were small-world and economical in the sense of providing high global and local efficiency of parallel information processing for low connection cost. Efficiency was reduced disproportionately to cost in older people, and the detrimental effects of age on efficiency were localised to frontal and temporal cortical and subcortical regions. Dopamine antagonism also impaired global and local efficiency of the network, but this effect was differentially localised and did not interact with the effect of age. Brain functional networks have economical small-world properties—supporting efficient parallel information transfer at relatively low cost—which are differently impaired by normal aging and pharmacological blockade of dopamine transmission.

2,208 citations

Journal ArticleDOI
05 Oct 2006-Neuron
TL;DR: Evidence that certain brain disorders, such as schizophrenia, epilepsy, autism, Alzheimer's disease, and Parkinson's are associated with abnormal neural synchronization is reviewed to suggest close correlations between abnormalities in neuronal synchronization and cognitive dysfunctions.

1,956 citations

Journal ArticleDOI
TL;DR: In this article, the potential functional role of the beta-band oscillations in cognitive processing, on the motor system and on the pathophysiology of movement disorders is discussed. But the authors focus on the maintenance of the current sensorimotor or cognitive state.

1,900 citations