A

Mercy Strategy 59

This pairing in fact makes sense in the light of mental behavior. At this
point in the book, we probably have the impression that Mercy thought
operates in isolation, apart from other modes of thought. This is not the
case. Normal thought involves extensive interaction between mental modes.
In addition, two of the composite styles generate precisely the pairing
which is noted by neurologists. Contributor thought combines Server and
Perceiver memories. Therefore, it makes sense that there would be a close
relationship between left dorsolateral frontal cortex (the region I associate
with Server thought) and right dorsolateral frontal cortex (the area
connected with Perceiver thinking). Similarly, Exhorter thought combines
Mercy and Teacher modes, making it reasonable that the right and left
orbitofrontal cortices (the corresponding brain regions) should be lumped
together.

Fortunately, where behavioral studies are lacking, brain wiring comes
to the rescue. Each hemisphere contains two major bundles of conduction
fibers, called the uncinate fasciculus and the arcuate fasciculus. The
uncinate fasciculus interconnects the temporal lobe with the orbitofrontal
cortex, and the arcuate fasciculus connects mainly the parietal lobe with
the dorsolateral frontal cortex.A Thus, each of the four major regions in the
back of the cortex is strongly related to a corresponding quadrant in the
front: the right parietal and right dorsolateral frontal regions are related, the
left parietal and left dorsolateral areas are related, the left temporal lobe
forms a unit with the left orbitofrontal lobe, and the right temporal lobe
forms a unit with the right orbitofrontal region.

Superior (Top)

Inferior (Bottom)

THE LEFT HEMISPHERE OF THE BRAIN

Temporal Lobe

Parietal Lobe

Posterior

(Back)

Anterior
(Front)

Frontal Lobe

B roca's

A rea W ernicke's

A rea

Orbitofrontal

Cortex

A Some of the fibers connecting inferior (lower) frontal with temporal

lobes also pass through the arcuate fasciculus.