Hemispheric lateralization during active and imagined movements assessed by transcranial doppler ultrasound

This study investigates the vascular effect of hemispheric lateralization during active and imagined elbow flexion–extension (EFE), using transcranial Doppler ultrasound (TCD). In order to assess the potential impact of the working side and of task repetition on the magnitude and time course of hemodynamic responses. Nineteen healthy right-handed participants were bilaterally monitored for cerebral blood flow velocity (CBFV) in the middle cerebral arteries (MCAs) during both active and imagined EFE. Significant lateralization during active movement, particularly with the left arm, were detected while imagined movements showed reduced lateralization and a delayed hemodynamic response. No effect of task repetition was observed but a left-ward trend of lateralization was observed during repeated motor imagery tasks, compared to active movements, suggesting that active engagement may influence cerebral activation and hemispheric lateralization. These findings offer insights into the neural correlates of motor tasks and have potential applications in brain-computer interfaces (BCIs) and neurorehabilitation.