Purpose: The present study was carried out to investigate possible electroencephalographic changes induced by choking in judo (shime-waza) by means of spectral analysis and brain mapping.
Methods: Power spectral changes in Electroencephalography (EEG) were recorded in six experienced judoka who underwent a choking trial with a "shime-waza choking" technique called juji-jime.
Results: A significant increase of global field power in the delta- and theta-range occurred, while physiological alpha-power decreased. These changes in the low-frequency range reached a statistically significant level within a time span up to 20 s after choking, which was performed at an average choking time of 8 s. In no case did choking provoke neuropsychological symptoms. Yet, spectral EEG-analysis revealed subclinical changes of brain function.
Conclusions: Choking in judo may induce subclinical electroencephalographic perturbations. The extent and duration can be objectified by means of spectral analysis of EEG data, global field power computation, and brain-mapping representation.