🥇 Anatomía de los GANGLIOS BASALES. (Núcleos Basales) ¡Explicación Sencilla!

Introduction to Basal Ganglia

Overview of the Video

• The video introduces the topic of basal ganglia, also referred to as nuclei at the base of the brain.

• The presenter, Juan José Sánchez, welcomes viewers and sets the stage for discussing these important brain structures.

Nuclei Classification

• The discussion will focus on two main nuclear groups: the striatum and the claustrum (or antemuro).

• Some literature includes additional nuclei related to telencephalon, such as amygdaloid body and subthalamic nuclei, but these will not be covered in this video.

Anatomy of Basal Ganglia

Importance of Studying Basal Nuclei

• Basal nuclei serve as a bridge between cerebral cortex and other central nervous system structures, highlighting their significance in neuroanatomy.

• These formations consist of gray matter located near the base of the brain. Understanding their anatomy is crucial for comprehending brain function.

Visual Representation

• A diagram illustrates two major complexes: striatum (indicated in green) and thalamus (medial agglomerate). This visual aids in understanding their spatial relationships within the brain.

Detailed Structure of Striatum

Components of Striatum

• The striatum comprises three primary nuclei: caudate nucleus, lenticular nucleus (which itself has three smaller nuclei), and nucleus accumbens (to be discussed later).

Caudate Nucleus Characteristics

• The caudate nucleus resembles a horseshoe or "C" shape with anterior concavity, wrapping around the thalamus closely associated with lateral ventricles.

• Its head forms part of the lateral wall for both frontal horn and atrium of lateral ventricle; its tail connects with temporal horn forming its roof.

Relationship with Lateral Ventricles

Anatomical Connections

• The caudate nucleus's close relationship with lateral ventricles is emphasized; it plays a significant role in surrounding these cavities within the brain structure.

Understanding the Caudate Nucleus and Its Relationships

Overview of the Caudate Nucleus

• The caudate nucleus bulges at the lateral ventricle level, with its tail forming the roof of the temporal horn. It wraps around the thalamus, while the lenticular nucleus is positioned further away.

• The caudate nucleus consists of three portions: a thick head (superior anterior), a body that narrows backward with a curvature around the thalamus, and a tail that extends laterally and anteriorly.

• The head, body, and tail of the caudate nucleus are illustrated in an image; it reaches towards the amygdaloid nucleus. The thalamus is shown in red, while part of the lenticular nucleus (globus pallidus) is depicted in blue.

Structural Relationships

• The head of the caudate nucleus is made up of gray matter and protrudes into the lateral ventricle. As it extends backward, it transitions into its body above the thalamus.

• The body lies above the thalamus and has close relationships with both gray matter structures like the lenticular nucleus and white matter structures such as internal capsule.

• Each head of the caudate nucleus is separated by septum pellucidum from one another. This structure also separates them from lateral ventricles.

Connections Between Structures

• Within each head's inner part lies a group of fibers connecting to the lenticular nucleus known as "caudolenticular gray bridges," which pass through internal capsule.

• Internal capsule comprises white matter that facilitates communication between nuclei; these striated fibers connect both nuclei at their heads.

Body Structure Insights

• In frontal sections where only bodies are visible, they run superior to thalamus and laterally to lateral ventricle. Ependyma covers their upper face while being closely related to other structures below.

• Stria terminalis runs alongside this body throughout its journey; it’s important for understanding relationships within brain anatomy.

Tail Characteristics

• The tail forms part of temporal horn roof within lateral ventricle; images illustrate how it connects to amygdala body on both sides.

Lenticular Nucleus and Its Components

Structure of the Lenticular Nucleus

• The lenticular nucleus exhibits a triangular shape when viewed in both frontal and transverse sections, with its vertex located at the midline.

• It consists of three segments: the putamen, lateral globus pallidus, and medial globus pallidus. The putamen appears darker than the other components.

• A minimal separation exists between these nuclei, identified as the medullary laminae, which are composed of white matter.

Medullary Laminae Details

• There are two types of medullary laminae:

• External (lateral) medullary lamina between the putamen and lateral globus pallidus.

• Internal (medial) medullary lamina between the lateral and medial globus pallidus.

• The term "globus pallidus" refers to its paler color compared to the putamen.

Relationships with Surrounding Structures

• The lateral portion of the lenticular nucleus is adjacent to the external capsule; its inferior face contacts subthalamic regions.

• Anteriorly, it connects with the head of the caudate nucleus via gray bridges known as caudo-lenticular bridges.

Additional Nuclei Associated with Lenticular Nucleus

• The nucleus accumbens is located anteriorly where the caudate nucleus meets the putamen and is dorsal to the olfactory tubercle.