Corpora Quadrigemina are four rounded eminences, which form the upper part of the midbrain and lie under posterior part of the cerebral hemispheres. They consist of two parts of colliculi (anterior and posterior)separated by a transverse groove. The anterior colliculi are larger and placed higher in level than the posterior and are known as nates.
Midbrain made up of these parts of brain- Corpora Quadrigemina Cerebral aqueduct Cerebral peduncles
The basal ganglia consists of masses of gray mater or nuclei, viz. the caudate and lenticular nuclei, claustrum and amygdaloid within the cerebral hemisphere. The caudate and lenticular nuclei are incompletely separated by tracts of white mater called the internal capsule . The internal capsule actually consists of a masses of projection fibres connecting cerebral
Fornix of Brain is composed of longitudinal white fibers that arch over the thalamus and the third ventricle. It consists of a body and two pairs of pillars, anterior and posterior. The body is formed by the fusion of the two arches by which the fornix is composed. It is triangular and overlies the anterior part of
Pineal gland Pineal body is a small ovoid or fusiform gland situated dorsally in a deep depression between the thalami and the corpora quadrigemina. It is attached to the postero-superior quadrant of the third ventricle by a hollow stalk, which is a small recess of the third ventricle. Immediately under the posterior part of the
Interbrain-thalamus is a large ovoid mass of gray mater situated obliquely across the dorsal face of cerebral peduncles, so that the two bodies meet in front at a right angle. Medially they are fused to large extent and around this area of adhesion is an annular space called the third ventricle. The dorsal face of
Olfactory bulbs Rhinencephalon or Olfactory bulbs are oval elongated structures in each hemisphere, situated at the anteroventral aspect of the frontal pole and are lodged in the olfactory fossae Each bulb receives olfactory nerves coming from the nasal mucosa through the olfactory perforations of the cribriform plate of the ethmoid bone. The olfactory tract is
Hippocampus is an invagination of the cerebral cortex at the lateral ventricle through the hippocampal sulcus. This gyrus curves from the deep face of the piriform lobe around the thalamus and forms the posterior part of the floor of the lateral ventricle. By careful blunt dissection along the posterior horn of the lateral ventricle into
It is the largest mass of commissural fibres that connect the two cerebral hemispheres. The fibres spread out laterally in a radiating manner in the central white mater of each hemisphere. These fibres are crossed by the ascending fibres of the internal capsule. The central part or truncus between the two hemispheres appears as arched
In each hemisphere, the cortical areas have been identified depending on their action. They are The motor area is the anterior and posterior sigmoid gyri which wind round the crucial fissure as their axis. Coronal gyrus contains the somaesthetic area and is located below and lateral to the coronal sulcus. The postsylvian gyrus contains the
