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The differential representation of the toes/feet and fingers/hands along the medial and lateral surfaces of the cerebral cortices, respectively, may have diagnostic utility. Normative data for errors for toe and finger graphaesthesia and gnosis, as well as foot and finger agility, were collected for 86 children (ages 7 to 14). The fingers were more agile than the feet, and the right side of the body was more agile than the left side, regardless of age. A marked improvement in toe gnosis, but not in finger gnosis occurred in children after 11-12 years of age. A statistically significant interaction between laterality and gender was due to the greater numbers of errors for both toe and finger gnosis, displayed by girls for the left sides of their bodies compared to their right sides. This discrepancy was not significant for boys.

A total of 40 normal men and women were exposed under double blind conditions for 20 min to either sham-conditions or to 1 microT (10 mG) electromagnetic fields (known to produce long-term potentiation within hippocampal slices) that were applied primarily over the right temporal lobe, over the left temporal lobe or over both temporal lobes homogeneously. The men and women who received the stimulation over the right hemisphere rated their experiences as significantly more pleasant than those who received the same stimulation over the left hemisphere [eta = 0.51]. Covariance for the variation in ambient geomagnetic activity, which was negatively correlated with pleasantness, increased the significance of the experimental treatment. The potential clinical utility of applying computer-generated local and penetrative but weak intensity complex magnetic fields over portions of the human brain is discussed.

In two separate experiments a total of 71 volunteers were asked to generate spontaneous narratives that were scored automatically by the Whissell Dictionary of Affect. During the narratives, weak (1 microT; 10 mG) magnetic fields were applied briefly through the temporal planes. In Experiment I, subjects who were exposed to simple sine wave or pulsed fields generated more scorable words that indicated lower activation and evaluation than sham-field conditions. In Experiment II subjects exposed to a computer-generated wave form, designed to simulate neuronal burst firing, generated narratives dominated by more pleasantness and less activation than a reference group. The possibility that this approach could be utilized to study the affective dimension of language selection was indicated.