in this section of the lecture we're going to discuss all of the different basal nuclei and
where they itself so this is a coronal section taking Oh sort of that near the front of the
brain I've kind of given you a diagram of where it is here we can see the caudate nucleus and the
putamen and remember these are part of your striatum if you look at the slide a little
more closely you'll see that the caudate and the putamen are about the same color which indicates
that they have a common origin as the brain developed the next section in is the Globus
pallidus here and Globus pallidus means pale globe and you can see that it is actually a little paler
than the caudate and putamen the Globus pallidus has two subdivisions the internal segment which is
more medial and the external segment which is more lateral a little bit further back in the
brain move this bar just a little bit towards the back we still see our caudate but it's smaller we
see our putamen and the Globus pallidus and now we start to see a couple of more it parts of the
basal nuclei we can see the substantia nigra and this brain isn't stained for anything this is a
simply a fresh slice of a human brain and this is what the substantia nigra looks out like
naturally obviously brown spot is what they named it because that's exactly what it looks like and
then here it's a little hard to see but there's kind of an almond shaped nucleus here and this
is the subthalamic nucleus so again the caudate and putamen are part of the striatum the Globus
pallidus is part of the pallidum the substantia nigra is part of the brain stem and the subthalamic
nucleus is part of the diencephalon moving back even further in the brain about this level a
little bit more further back we've got a little more the brainstem in this section as you can see
cuz here's our pawns again we don't we have just a little bit of the caudate left we can no longer
see well here we go here's just a little bit of the of the putamen on this side of the brain we
can no longer see the Globus pallidus but we see a very beautiful substantia nigra here and here
the reason we don't see nearly as much of the caudate in this in this image is because the
caudate I'll draw it for you is kind of like a giant comma and it starts out really large in the
front and gets smaller and smaller as it goes back toward the the back of the brain so well
that doesn't sort of like that gets smaller and smaller trust me and so when you see the caudate
in anterior sections you see a very large piece of that of the caudate it's called the head of
the caudate and then it's like a ram's horn it curves around the lateral ventricles goes
a little bit more lateral getting thinner and thinner all the time as it comes posterior lis
and the next section is a horizontal section and you can see all the parts again so in this
horizontal section this is the front and this is the caudal pole so this is occipital lobe and
this is frontal lobe and the reason you know it's frontal lobe is because of your caudate
caudate's your buddy caudate is always going to tell you exactly where you are in the brain if
just knowing where that caudate is it's always in the anterior part and it's always going to
be medial to the internal capsule we'll talk a lot more about the internal capsule when we
talk about the cortex but we alluded to it in the motor systems as being the place where especially
this posterior limb where a lot of your motor information is passing out of the brain to go to
the brainstem and the spinal cord in this image we can see the putamen we can see just a little bit
of the Globus pallidus because the Globus pallidus the pale globe is kind of like a little ball that
sits nestled within the greater structure of the putamen we can also see the ventral thalamus can't
really see a very good picture of the subthalamic nucleus in this particular plane but it's in that
zone in the next set of slides we're going to talk about the circuitry of the basal nuclei