At present, the EEG method is used to study the neurophysiological mechanisms of human pain processing. A response to tonic somatic nociceptive stimulation has been detected in many frequency ranges of the EEG spectrum. The most common manifestations of the EEG response to various types of somatic pain include changes in the range of α oscillations; subjects who feel muscle pain caused by an injection of saline or capsaicin demonstrate a specific pain reaction in the α range, which significantly differs from a response to painless stimulation [1,2]. There are differences in the topography and intensity of responses to pain between the components of the α range, namely, the α 1 and α 2 rhythms [1, [3][4][5]. Data about the direction of changes in the α -rhythm power are contradictory. Normally, α oscillations are detected during atonic wakefulness [6,7]. Therefore, event-related EEG desynchronization is more probable when a subject feels pain, as this takes place during intense somatosensory stimulation [8,9]. At the same time, analysis of changes in the EEG caused by pain has demonstrated desynchronization as a response to tonic pain or a decrease in the power in the α -range of the spectrum, as well as an increase in the power of α oscillations in response to nociceptive stimulation [1-5, 10]. The power of α waves may increase after initial desynchronization, as well as when the sensation intensity in the stimulated region becomes lower than the pain threshold.The factors that cause differences in the responses to nociceptive stimulation in the α range are still unclear. It is necessary to continue the study of various factors such as the type, lateralization, and intensity of stimulation, as well as the afterpotentials in various ranges of EEG activity.Our purpose was to study the changes in power in the α 1 and α 2 ranges during and after tonic nociceptive stimulation in the form of a squeeze of the distal joint of the little finger. This form of stimulation provides a model of tonic articular pain. METHODSOur subjects were 12 healthy right-handers aged 20-56 years (35.5 years on average), including eight males and four females, who were students and employees of a research institute. All subjects had a distinct peak in the α range (8-13 Hz) of the spontaneous EEG spectrum. Each of them was informed about the study procedure in detail and gave his or her informed consent to participation in the test.The distal joint of the little finger was squeezed using a mechanical spring device with two cylindrical pins (diameter 4.8 mm), whose surface was covered with polyvinyl chloride. The intensity of squeezing at the outer and inner surfaces of the finger was controlled by the subjects.Together with the subjects, we selected low and high intensities of squeezing immediately before placing EEG electrodes. The former caused weak pain that was close to the threshold, and the subject could easily tolerate it or divert the attention away from it. The sensaAbstract -Examination of 12 healthy volunteers aged 20-56 years was ...