Cortical excitability in patients with essential tremor
Corresponding Author
Stefano Romeo MD
Dipartimento di Scienze Neurologiche, Università degli studi di Roma “La Sapienza,” Rome, Italy
Dipartimento di Scienze Neurologiche, Università degli studi di Roma “La Sapienza,” Rome, ItalySearch for more papers by this authorAlfredo Berardelli MD
Dipartimento di Scienze Neurologiche, Università degli studi di Roma “La Sapienza,” Rome, Italy
Istituto Mediterraneo di Neuroscienze “Neuromed,” Pozzilli, Italy
Search for more papers by this authorFrancesca Pedace MD
Dipartimento di Scienze Neurologiche, Università degli studi di Roma “La Sapienza,” Rome, Italy
Search for more papers by this authorMaurizio Inghilleri MD
Dipartimento di Scienze Neurologiche, Università degli studi di Roma “La Sapienza,” Rome, Italy
Search for more papers by this authorMorena Giovannelli MD
Dipartimento di Scienze Neurologiche, Università degli studi di Roma “La Sapienza,” Rome, Italy
Search for more papers by this authorMario Manfredi MD
Dipartimento di Scienze Neurologiche, Università degli studi di Roma “La Sapienza,” Rome, Italy
Istituto Mediterraneo di Neuroscienze “Neuromed,” Pozzilli, Italy
Search for more papers by this authorCorresponding Author
Stefano Romeo MD
Dipartimento di Scienze Neurologiche, Università degli studi di Roma “La Sapienza,” Rome, Italy
Dipartimento di Scienze Neurologiche, Università degli studi di Roma “La Sapienza,” Rome, ItalySearch for more papers by this authorAlfredo Berardelli MD
Dipartimento di Scienze Neurologiche, Università degli studi di Roma “La Sapienza,” Rome, Italy
Istituto Mediterraneo di Neuroscienze “Neuromed,” Pozzilli, Italy
Search for more papers by this authorFrancesca Pedace MD
Dipartimento di Scienze Neurologiche, Università degli studi di Roma “La Sapienza,” Rome, Italy
Search for more papers by this authorMaurizio Inghilleri MD
Dipartimento di Scienze Neurologiche, Università degli studi di Roma “La Sapienza,” Rome, Italy
Search for more papers by this authorMorena Giovannelli MD
Dipartimento di Scienze Neurologiche, Università degli studi di Roma “La Sapienza,” Rome, Italy
Search for more papers by this authorMario Manfredi MD
Dipartimento di Scienze Neurologiche, Università degli studi di Roma “La Sapienza,” Rome, Italy
Istituto Mediterraneo di Neuroscienze “Neuromed,” Pozzilli, Italy
Search for more papers by this authorAbstract
We used transcranial magnetic stimulation in 10 patients with essential tremor and 8 matched healthy subjects. A round stimulating coil was placed over the vertex and electromyographic activity was recorded from the first dorsal interosseous muscle. Paired transcranial stimuli were delivered at interstimulus intervals of 3, 5, 20, 100, 150, and 200 ms. The intensity of the conditioning stimulus was 80% of motor threshold at short and 150% at long interstimulus intervals (ISIs). We also measured the silent period obtained after a single magnetic pulse delivered at 150% of motor threshold during a submaximal muscle contraction. Patients and controls had similar motor threshold and similar latencies. Paired magnetic stimuli given at short and long ISIs at rest, and during a voluntary muscle contraction, elicited similar responses in both groups. The silent period evoked by transcranial magnetic stimulation had a similar duration in patients with ET and controls. In conclusion, these findings suggest that patients with essential tremor have normal cortical motor area excitability. © 1998 John Wiley & Sons, Inc. Muscle Nerve 21:1304–1308, 1998.
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