Unilateral Left-Hand Contractions Produce Widespread Depression of Cortical Activity after Their Execution

Abstract

The execution of unilateral hand contractions before performance has been reported to produce behavioral aftereffects in various tasks. These effects have been regularly attributed to an induced shift in activation asymmetry to the contralateral hemisphere produced by the contractions. An alternative explanation proposes a generalized state of reduced bilateral cortical activity following unilateral hand contractions. The current experiment contrasted the above explanation models and tested the state of cortical activity after the termination of unilateral hand contractions. Twenty right-handed participants performed hand contractions in two blocks, one for each hand. Using electroencephalogram (EEG), the broad alpha band and its asymmetry between hemispheres before, during, and after hand contractions were analyzed. During contractions, significant bilateral decrease in alpha amplitudes (indicating cortical activation) emerged for both hands around sensory-motor regions. After contractions, alpha amplitudes increased significantly over the whole scalp when compared to baseline, but only for the left hand. No modulation of hemispheric asymmetry was observed at any phase. The results suggest that unilateral hand contractions produce a state of reduced cortical activity after their termination, which is more pronounced if the left hand was used. Consequently, we propose that the reduced cortical activity (and not the persistent activation asymmetry) may facilitate engagement in subsequent behavior, probably due to preventing interference from other, nonessential cortical regions.

Choking interventions in sports: A systematic review

“…Left-hand contractions have been proposed to prime the visuospatial processes of the right hemisphere necessary for motor performance and to suppress the analytical processes of the left hemisphere linked to the step-by-step control of skill execution (Beckmann et al, 2013;Cross-Villasana, Gröpel, Doppelmayr, & Beckmann, 2015). In all five studies on left-hand contractions, researchers (e.g.…”

Investigating cumulative effects of pre-performance routine interventions in beach volleyball serving

“…Left-hand dynamic handgrip activates motor centers of the right hemisphere during the hand clenching [24,25]. Consequently, an increase in high Alpha is observed that spreads across the whole scalp [26]. High Alpha has an inhibitory function and can be said to and produces a state of cortical relaxation after the clenching.…”

“…High Alpha has an inhibitory function and can be said to and produces a state of cortical relaxation after the clenching. This involves a reduction of the dominant left-hemispheric activation [26]. The state of cortical relaxation after clenching the left (compared to right) hand is likely due to the higher level of connectivity and white matter in the right hemisphere (which controls the left hand), compared to the remaining parts of the brain.…”

“…The state of cortical relaxation after clenching the left (compared to right) hand is likely due to the higher level of connectivity and white matter in the right hemisphere (which controls the left hand), compared to the remaining parts of the brain. As a consequence, brain inhibitory mechanisms can be evoked to a greater extent in the right hemisphere when clenching the left hand [26]. Prior evidence has shown that the state of cortical relaxation is associated with enhanced readiness for motor actions [27,28].…”

An Investigation Into Handedness and Choking Under Pressure in Sport

“…The above evidence implies that a persistent left-hemispheric dominance may be linked to choking, whereas a symmetrical brain activation may underlie superior, skilled performance, which has been supported by Beckmann et al (2013) who primed the right hemisphere using left-hand contractions immediately prior to skill execution under pressure. Based on research demonstrating that people's right and left hand are mainly controlled via the contralateral brain hemisphere (Kim et al, 1993) Gröpel, Doppelmayr, & Beckmann, 2015). Thus, symmetrical brain activation patterns during skill execution under pressure leads to less likelihood of choking because there is less activation of the verbal-analytic centers and less conscious attention that interferes with automatic movement execution.…”