The structures deep inside cerebral white matter structures deep inside cerebral white matter

A BOOK THAT EXPLAINS BRIEFLY
ABOUT BASAL GANGLIA, INTERNAL

CAPSULE & LIMBIC SYSTEM

THE
STRUCTURES
DEEP INSIDE

CEREBRAL
WHITE MATTER

BY SURIA SHAHID

The basal ganglia are a
group of nuclei deep
within the cerebral
white matter.

Basal ganglia basically
consists of; globus
pallidus, putamen &
caudate nucleus.

Basal ganglia also
interconnected closedly
with the cerebral
cortex, thalamus and
brainstem.

This is 3D image of
basal ganglia.

Key:
Globus pallidus, putamen
Caudate nucleus
Thalamus (neighbour of basal ganglia)

Globus pallidus +
putamen = lentiform
nucleus.

Lentiform nucleus +
caudate nucleus =
corpus striatum.

The name was given because
the striped appearance due to

the presence of tracts.

Neighbours who
contributed
significantly to basal
ganglia; substantia
nigra and subthalamic
nuclei.

In order to let us have the
smooth movement, basal
ganglia refines movement
information from
precentral gyrus. It
eliminates unnecessary
movement and send refined
movement information
back to precentral gyrus
via thalamus. If basal
ganglia not functioning
well, people will get
jerking, shaking and stiff
movements.

Basal ganglia also
helps in controlling
muscle tone. People
with basal ganglia
problems have
Parkinson Disease.

Other functions of
basal ganglia; helps
coordinate cognitive
process such as
attention and memory.

It's also helps limbic
system to control
emotional behaviour
such as happy, fear
and rage.

INTERNAL CAPSULE

The space between the
thalamus and the lentiform

nuclei is filled by a
projection tract called the

internal capsule.

The space between the
thalamus and the lentiform

nuclei is filled by a
projection tract called the

internal capsule.

The internal capsule
consists of 2 parts; anterior

limb, genu and posterior
limb.

The anterior limb is the
pathway for the frontopontine

tract (projection tract from
the prefrontal cortex to the
pons) and anterior thalamic
radiation (projection tract

from anterior and medial
thalamus to cerebral cortex).

While the genu becomes the
pathway of the corticobulbar
tract and part of the superior

thalamic radiation.

The longer posterior limb
becomes the pathway for the
corticospinal, corticopontine,

corticorubral, superior
thalamic radiation, basal
ganglia tract from the globus
pallidus and subthalamic

nuclei to cortex.

In conclusion, the internal
capsule is a projection tract
located between the thalamus
and lentiform nuclei and has 3

parts namely the anterior
limb, genu and posterior limb.

LIMBIC
SYSTEM

Limbic system;
a group of

structures that lie in the
border zone between the
cerebral cortex and the

hypothalamus.

The limbic system consists
of cortical and subcortical

structures.

Cortical:
1.Limbic lobe
2.Hippocampal formation
3.Septal area
4.Olfactory areas

Subcortical:
1. Amygdaloid
2. Hypothalamus
3.Anterior nucleus of
thalamus
4.Habenular nucleus
5.Reticular formation

Limbic lobe; consists of
cingulate gyrus,
isthmus,
parahippocampal and
uncus.

Hippocampal
formation;
hippocampus, dentate
gyrus, induseum
griseum and some other
structures.

Amygdala fuses with
the anterior end of the
tail of the caudate
nucleus.

Amygdala; receives afferent
fibers from primary olfactory
cortex, hippocampus,
hypothalamus, thalamus,
cerebral cortex and brainstem
reticular formation and some
other places.

The amygdala receives fibres
from and sends fibres to
the reticular formation. The
reticular formation extends
throughout the length of the
brainstem.

The functions of limbic system:

1.Able to influence many aspects of
emotional behavior. These include
particularly the reactions of fear
and anger and the emotions
associated with sexual behavior.

2.Hippocampus is concerned with
converting recent memory to
longterm memory.

3.No evidence of limbic system role
in olfactory function.

In conclusion, because the anatomical
connections of the limbic system are
extremely complex and their
significance is not fully understood,
committing all of them to memory is
unnecessary.

The results of neurophysiologic
experiments, which have included
stimulation and ablation of different
parts of the limbic system in
animals, are not entirely clear.

Nevertheless, certain important roles
have been inferred: (1) Involved In the
development of sensations of emotion
and with the visceral responses
accompanying those emotions, and (2)
the hippocampus is concerned with
recent memory.

That all about Basal
Ganglia, Internal capsule,
and Limbic System. Hope

you get the necessary
information that can help
you understand the brain

better.
Thanks for reading....