Minds and Computers : An Introduction to the Philosophy of Artificial Intelligence

limbic system
thalamus
temporal lobe
parietal lobe
occipital lobe
pineal gland
midbrain
medulla
cerebellum
frontal lobe
pons
Figure 4.1
Mid-sagittal section.

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is often described as a ‘sensory gateway’. It routes sensory informa-
tion (with the exception of olfaction) from the sensory apparatus to
the relevant primary processing area. It contains, among other struc-
tures, the lateral geniculate nucleus which is specialised for receiving
information from the eyes and routing it to the primary visual pro-
cessing cortex, and the medial geniculate nucleus which is specialised
for receiving information from the ears and routing it to the primary
auditory processing cortex.
The pineal gland and the pituitary gland are both endocrine glands –
they are involved in the secretion of neurotransmitters. The pituitary
gland regulates the release of a number of various neurotransmitters,
including human growth hormone and oxytocin. The pineal gland is
mainly involved with the production of melatonin. Interestingly, the
pineal gland was believed by Descartes to be the locus of interaction
with the immaterial soul.
The hypothalamus controls the secretions of most of the endocrine
glands and thereby regulates a wide range of bodily functions, includ-
ing thirst and appetite, temperature, and sexual and circadian cycles.
This exhausts the structures of the brain stem. The rest of the brain
consists of the cerebral hemispheres, the limbic system, the basal
ganglia and the olfactory bulbs.
The olfactory bulbs are responsible for primary olfactory process-
ing. As mentioned earlier olfaction, or smell, is the only sensory
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