Associative cortico-cortical plasticity may affect ipsilateral finger opposition movements

• Published in: Behavioural brain research 2011, Vol.216 (1), p.433-439
• Main Authors: Rizzo, V., Bove, M., Naro, A., Tacchino, A., Mastroeni, C., Avanzino, L., Crupi, D., Morgante, F., Siebner, H.R., Quartarone, A.
• Format: Article
• Language: English
• Subjects: Adult; Analysis of Variance; Associative plasticity; Behavioral psychophysiology; Biological and medical sciences; Cerebral Cortex - physiology; Cortico-cortical connectivity; Electromyography; Evoked Potentials, Motor - physiology; Female; Finger opposition movements; Fingers - physiology; Functional Laterality - physiology; Fundamental and applied biological sciences. Psychology; Humans; Interhemispheric inhibition; Male; Middle Aged; Motor cortex; Movement - physiology; Neuronal Plasticity - physiology; Neurons - physiology; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Transcranial Magnetic Stimulation
• ISSN: 0166-4328; 1872-7549
• DOI: 10.1016/j.bbr.2010.08.037

▶ cc-PAS modulates interhemispheric inhibition (IHI) in the human brain. ▶ cc-PAS influences the performance of a simple finger opposition movement. ▶ The attenuation of IHI after cc-PAS correlated with the reduction of ITI. We have recently demonstrated that cortico-cortical paired associative stimulation (cc-PAS) can modulate interhemispheric inhibition (IHI) in the human brain. Here we further explored the after effects of cc-PAS on fine hand movements. Ten healthy right-handed volunteers received 90 paired transcranial stimuli to the right and left primary motor hand area (M1 HAND) at an interstimulus interval (ISI) of 8 ms. We studied the after effects of cc-PAS on the performance of repetitive finger opposition movements of different complexity on both hands using a sensor-engineered glove. A quantitative evaluation of the following parameters was performed: Touch Duration (TD), Inter Tapping Interval (ITI) and Number of Errors (NE). We confirmed previous data by showing that left-to-right and right-to-left cc-PAS attenuated IHI. The new finding is that both left-to-right and right-to-left cc-PAS were able to influence the performance of a simple finger opposition movement changing the duration of TD and ITI. Interestingly the effect on the two hands was opposite in direction. These results provide further insight that cc-PAS can induce associative plasticity in connections between the targeted cortical areas influencing motor hand performances. These results may be relevant for future rehabilitative applications.