Scientific publications

Alpha and beta oscillatory activity during a sequence of two movements

Alegre M, de Gurtubay IG, Labarga A, Iriarte J, Malanda A, Artieda J.
Clinical Neurophysiolgy Section, Department of Neurology, Clínica Universitaria, Facultad de Medicina, Universidad de Navarra, Avda, Pío XII, 36, 31008 Pamplona, Spain.

Magazine: Clinical Neurophysiology

Date: Jan 1, 2004

Neurophysiology [SP]

We studied movement-related electroencephalographic oscillatory changes in the alpha and beta range during a sequence of two movements in 7 healthy volunteers, in order to investigate the relationship between these changes and each component in the sequence.

The sequence consisted of a wrist active extension-passive flexion followed by a first and second finger pincer. A total of 10.5 s sweeps were recorded using the level of surface electromyographic (EMG) activity in wrist extensors as trigger, including a 7.5 s pre-stimulus.

The sweeps were also realigned manually offline using as trigger the end of the first EMG burst, or the beginning of the second movement. An index of the changes in non-phase-locked energy in the 7-37 Hz range was obtained by averaging single-sweep time-frequency transforms.

The duration of each of the movements in the sequence and the relationship between them were compatible with the use of two different motor programmes in the sequence. In the beta band, a decrease in energy (event-related desynchronisation, ERD) began 1.5 s before the onset of the first movement, and was sustained until the end of the second movement.

No energy increases were observed until the end of the second movement. In the alpha band, the ERD began 0.5 seconds before the first movement and was sustained throughout the recording.

These findings suggest that the beta-event-related synchronisation is related to the end of the whole motor process, and not to the end of each motor programme.

CITATION  Clin Neurophysiol. 2004 Jan;115(1):124-30



The Clínica is the greater private hospital with technological equipment of Spain, all in a single center.

Imagen de un PET, tecnología de vanguardia en la Clínica Universidad de Navarra


The professionals of the Clínica perform continuous research and training, always to the benefit of the patient.

Imagen profesionales de la Clínica Universidad de Navarra


Learn why we are different from other healthcare centers. Quality, speed, comfort and results.

Imagen del edificio de la Clínica Universidad de Navarra