Functional Interplay between Posterior Parietal and Ipsilateral Motor Cortex Revealed by Twin-Coil Transcranial Magnetic Stimulation during Reach Planning toward Contralateral Space

• DOI: 10.1523/jneurosci.0957-08.2008
• Publication Date: 2008-06-04T17:23:49Z
• Authors: G. Koch; M. F. Del Olmo; B. Cheeran; S. Schippling; C. Caltagirone; J. Driver; J. C. Rothwell
• Keywords: Premotor cortex; Parietal lobe

Posterior parietal cortex (PPC) has connections with motor and premotor cortex, thought to transfer information relevant for planning movements in space. We used twin-coil transcranial magnetic stimulation (tcTMS) methods show that the functional interplay between human right PPC ipsilateral (M1) varies current plans. tcTMS during reaction time of a reach task revealed facilitatory influences on M1 only when (contralateral) leftward rather than rightward reach, at two specific intervals (50 125 ms) after an auditory cue. The earlier reach-direction-specific influence from occurred subjects were blindfolded or targets presented briefly, so visual feedback corrections could not occur. PPC–M1 was similar within left hemisphere but planned reaches, peaks 50 100 ms. Functional is enhanced early stages contralateral direction.