Medial geniculate body

The medial geniculate body is the medical name for a part below the hypothalamus that controls our limbs and trunk. The lateral geniculate body is part of the hypothalamus and is located near the optic nerve center. We should also pay attention to the hygiene of our brain use in our daily lives, always maintain a happy mood, use our brain moderately, and not overuse it. People who are often angry tend to have poor memory, so treat life with a calm mind.

1. Medial geniculate body:

The medial geniculate body is a small hillock located below the occipital thalamus. It belongs to the posterior part of the thalamus and is connected to the hypothalamus of the midbrain through the hypothalamic arm. The cell group on its deep surface is the relay nucleus of the auditory fibers of the lateral lemniscus. The fibers emitted by the nucleus form the auditory radiation, which reaches the auditory area of ​​the brain (transverse temporal gyrus) through the posterior crus of the internal capsule. The medial geniculate is the last junction of the auditory conduction pathway.

2. Lateral geniculate body:

The lateral geniculate body is located in the diencephalon and is part of the thalamus of the lateral geniculate system. The lateral geniculate body is located in the posterior part of the thalamus, just outside and below the pulvinar, and is the subcortical center of vision. The lateral geniculate body is connected to the superior colliculus by the superior arm of the quadrigeminal body. Its lateral side is connected to the optic tract, its medial side is connected to the superior colliculus arm, and the cell cluster on the deep side is the third-order neuron of the visual conduction pathway. Its soma sends out fibers to form the optic radiation, which passes through the posterior crus of the internal capsule and ends at the visual areas above and below the calcarine sulcus.

3. Lateral lemniscus:

The trapezoidal fibers run to the anterior and lateral sides of the tegmentum, turn upward on the outside of the superior olivary nucleus, and are called the lateral lemniscus. The lateral lemniscus is part of the auditory pathway. It then ascends along the outer edge of the tegmentum, passes through the midbrain, and ends at the medial geniculate body of the thalamus.

The lateral lemniscus is the ascending auditory fiber bundle. It originates from the anterior and posterior nuclei of the cochlear nerve at the upper end of the medulla oblongata, crosses between the base of the pons and the tegmentum, crosses the midline to form the trapezoid body, then turns upward, rises along the outer edge of the medial lemniscus, and ends at the medial geniculate body of the posterior thalamus. It is the second order fiber in the auditory conduction pathway.

4. Thalamus

The thalamus, also known as the dorsal thalamus, is an oval mass of gray matter located at the base of the brain, adjacent to the third ventricle internally and the internal capsule externally. In humans, the thalamus is an important relay station for sensory and motor impulses under the cerebral cortex, and is also a subcortical high-level integration center for multiple neural impulses.

Anatomy:

1. Medial geniculate body:

The medial geniculate body is located below the occipital thalamus, one on each side, in the shape of a protrusion. Inside it is a gray matter nucleus called the medial geniculate nucleus, which is the subcortical center of hearing and is connected to the hypothalamus of the quadrigeminal body of the midbrain through the hypothalamic arm.

The medial geniculate body is the terminal nucleus of the lateral lemniscus. The fibers emitted from the nucleus form auditory radiation, which reaches the auditory center of the cerebral cortex. It is the last relay nucleus in the auditory conduction pathway.

2. Thalamus

The thalamus is an oval gray matter mass in the dorsal medial part of the diencephalon, with a sagittal diameter of approximately 3 cm and a transverse and longitudinal diameter of 1.5 cm each. The lateral surface is the posterior limb of the internal capsule; the medial surface is the upper part of the lateral wall of the third ventricle; the dorsal surface is the floor of the lateral ventricle, the lateral end of which is separated from the caudate nucleus by the stria terminalis; the ventral surface is the hypothalamus and subthalamus. The thalamus is the site of neuronal exchange for various sensations transmitted to the nervous system from the internal and external environment, including general sensation, proprioception, and special sensation (except smell). It constitutes a specific projection system of the thalamus, so it is known as the highest sensory center under the cortex.