The metathalamus consists of the medial and
lateral geniculate body situated on each side of the midbrain below the
thalamus.
MEDIAL GENICULATE BODY:-
It is an oval elevation situated just
below the pulvinar of the thalamus and lateral to the superior colliculus. The
Inferior brachium connects medial geniculate body is as follows:-
AFFERENTS:-
1. LATERAL Lemniscus.
2. Fibers from both Inferior colliculus.
EFFERENTS:-
It gives rise to the radiation going to
the auditory area of the Cortex (In the temporal lobe) through sublentiform
part of the internal capsule.
FUNCTIONS:-
It is the last relay station on the
pathway of auditory impulses to the
cerebral cortex.
LATERAL GENICULATE BODY:-
It is a small elevation situated anterolateral
to the medial geniculate body below the thalamus. It is overlapped by the medial part of the temporal lobe and is connected to superior colliculus by the
superior brachium.
STRUCTURE:-
It has six layers i.e 1,4,6(pink) receive
contralateral optic fibers and layer 2,4,6(light blue) receive Ipsilateral optic fibers.
CONNECTIONS:-
1. AFFERENT:- Optic tract (lateral root )
2. EFFERENT:- It gives rise to the optic
radiation going to the visual area of the cortex through retrolentiform part of
the internal capsule
FUNCTIONS:-
It is the last relay station on the visual
pathway to the occipital cortex.