The Neurosurgeon

Satisfactory Essays
The Neurosurgeon

The temporal lobe comprises all the tissue that lies below

the Sylvian fissure and anterior to the occipital and parietal

cortex. The temporal regions can be divided on the lateral

surface into those that are auditory (Brodmann’s area) and those

that form the ventral visual stream on the lateral temporal

lobe. The visual regions are referred to as either

inferotemporal cortex or by von Bonin and Bailey’s designation,

TE. The sulci of the temporal lobe contains most of the cortex.

The superior temporal sulcus (STS) which separates the superior

and middle temporal gyri can be divided into many sub regions.

It receives input from auditory, visual, and somatic regions as

well as the frontal and parietal regions and the paralimbic

cortex. The medial temporal region includes the hippocampus

(and surrounding cortex) and the fusiform gyrus. The posterior

end of the temporal lobe is referred to as the parahippocampal

cortex and includes areas known as TH and TF. The fusiform

gyrus and interior temporal gyrus are part of the lateral

temporal cortex. The uncus refers to the anterior extension of

the hippocampus. The hippocampus, as well as the amygdala, are

buried deep within the temporal lobe.

The temporal lobes have many internal connections which

project to the sensory systems, to the parietal and frontal

regions, to the limbic system, and to the basal ganglia. The

neocortex of the left and right lobes is connected to the

archicortex. Studies have demonstrated four projection pathways

of information in the temporal lobe which each form separate

functions. First, auditory and visual information processes

from the primary regions ending in the temporal pole form the

ventral stream of visual processing. Its function is thought to

be stimulus recognition. Second, auditory, visual, and somatic

project into the superior temporal sulcus whose function is

stimulus categorization. Third, auditory and visual information

is projected to the medial temporal regions including the

hippocampus (called the preforant pathway) and the amygdale.

This pathway is crucial to long term memory. Fourth auditory

and visual information goes to the area of the frontal lobe

which is necessary for various aspects of movement, control,

short term memory, and affect.
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