Tonic neuronal activation during simple and complex finger movements analyzed by DC-magnetoencephalography.
Functional neuroimaging techniques map neuronal activation indirectly via local concomitant cortical vascular/metabolic changes. In a complementary approach, DC-magnetoencephalography measures neuronal activation dynamics directly, notably in a time range of the slow vascular/metabolic response. Here, using this technique neuronal activation dynamics and patterns for simple and complex finger movements are characterized intraindividually: in 6/6 right-handed subjects contralateral prolonged (30 s each) complex self-paced sequential finger movements revealed stronger field amplitudes over the pericentral sensorimotor cortex than simple movements. A consistent lateralization for contralateral versus ipsilateral finger movements was not found (4/6). A subsequent sensory paradigm focused on somatosensory afferences during the motor tasks and the reliability of the measuring technique. In all six subjects stable sustained neuronal activation during electrical median nerve stimulation was recorded. These neuronal quasi-tonic activation characteristics provide a new non-invasive neurophysiological measure to interpret signals mapped by functional neuroimaging techniques.
Leistner
Stefanie
S
Neurophysics Group, Department of Neurology, Charité - University Medicine Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203 Berlin, Germany. stefanie.leistner@charite.de
Wuebbeler
Gerd
G
Trahms
Lutz
L
Curio
Gabriel
G
Mackert
Bruno-Marcel
BM
D000328:Adult; D001931:Brain Mapping; D005073:Evoked Potentials, Somatosensory / Q000502:physiology / Q000528:radiation effects; D005260:Female; D005385:Fingers / Q000502:physiology*; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D009044:Motor Cortex / Q000502:physiology* / Q000528:radiation effects; D009068:Movement / Q000502:physiology* / Q000528:radiation effects; D011597:Psychomotor Performance / Q000502:physiology* / Q000528:radiation effects