Premotor Programming and Cortical Processing in the Cerebral Cortex

Abstract

Slow brain potentials were averaged from 12–15 EEG records (t = DC or 5 s) before and during voluntary hand movement and writing, spatial vision, language, and calculation tasks without vocalization and with visual fixation. EOG and writing pressure or EMG were recorded simultaneously. Skilled actions caused largest negative potentials in the contralateral sensorimotor hand area. Left-sided lateralization or bilaterally equal surface-negative potential shifts appeared during language and calculation tasks in 90% of the right-handers and in 75% of the left-handers. Right-sided lateralizations occurred during the viewing of perspective Necker figures or random-dot stereograms in the large majority of all subjects.

The Time Course of Parietal Activation in Single-digit Multiplication: Evidence from Event-related Potentials

“…In particular, converging evidence has been accumulated that the left parietooccipito-temporal region of the brain is crucial in calculation processes. One line of evidence comes from electrophysiological studies (Altenmüller, Jung, Winkler, & Landwehrmeyer, 1989;Inouye, Shinosaki, Iyama, & Mastumoto, 1993;Papanicolaou, Schmidt, Moore, & Eisenberg, 1983;Shepard & Gale, 1982). Altenmüller et al (1989) found a preponderance of left posterior activation in 65% of his subjects as indexed by a slow negative DC-shift during a complex addition task (i.e.…”