welcome to the second part of this module here we will discuss the anatomy of the rest of the major brain parts like the diencephalon the pituitary gland the cerebellum the midbrain pons and the medulla adult fate of the diencephalon are the thalamus hypothalamus and the epithalamus the diencephalon serves as the rostral brain stem between the cerebrum and the midbrain by its position the diencephalon technically serves as a relay center the thalamus is composed of two oval masses mainly grey matter connected by the interthalamic adhesion it is the largest part of the diencephalon it serves as a relay center for sensory impulses except for olfaction to the cerebral cortex here is a dorsal view of the thalamus to show the oval masses mentioned the hypothalamus is located at the floor of the diencephalon located beneath the thalamus as shown here the hypothalamus is the master gland of the body as it controls numerous vital functions such as the heart rate temperature blood pressure gastrointestinal secretions and motility among others a structure called infundibular stop connects the hypothalamus to the cortex thalamus and other parts of the brain here is a picture showing the stock connecting the hypothalamus with the anterior and posterior lobes of the pituitary gland the last member of the diencephalon is the epithalamus it is composed of the pineal gland and the habenula the pineal gland is an endocrine organ in mammals its primary secretion the melatonin appears to be important in the circadian rhythms and sleep cycles the other hand the habenula is an important part of the olfactory pathway since we now know the location of the hypothalamus let us then locate the parts of the brain that was once called the master gland of the body which is closely associated with the hypothalamus the pitwitaric gland or the hypothesis for orientation purposes again this is the hypothalamus and this is the pituitary gland or the hypothesis the pituitary gland is composed of an anterior lobe or the adeno hypothesis and a posterior lobe called the neural hypothesis remember that there is a communication between the hypothalamus and the pituitary gland via the infundibular stock in your endocrinology class you will learn the physiological relationship between these two parts of the brain and the specific hormones that they release remember the pituitary gland is encased in a depression in the spinoid bone called the cella torsica next let us have a look at the little brain called the cerebellum here is a lateral view of the brain and here is the cerebellum the cerebellum is the second largest division of the brain next to the cerebrum dislocated dorsal to the pons and medulla and cuddle to the occipital lobe from which it is separated by the transverse fissure it is roughly globular and its surface features fissures that divide the grey mass into lobes and smaller fissures that further subdivide the mass into small lobules called folia the cerebellum functions as a motor reflex center in coordinating subconscious and conscious skeletal muscle movements let us identify some of the parts of the cerebellum here is a dorsal view of an isolated cerebellum the vermis is the central part of the cerebellum it was named vermis because it resembles a worm it is further subdivided into a caudal lobe and a rostral lobe on the other side of the vermis are the structures called lateral masses folia are the laminae at the surface of the cerebellum internally there is a distinct feature of the cerebellum and that is the arbor vitae anatomists often refer to this as the tree of life as it resembles the tree these are actually white matter tracks branching into the cerebellum next we proceed to the midbrain the midbrain is the only adult structure that arises from the mesencephalon here is the location of the midbrain it is located between the diencephalon and the pons connecting the lower brain centers and the spinal cord to the higher brain centers for you to imagine here is a schematic illustration of the brain showing the parts of the brain stem in relation to the location of the midbrain the midbrain is composed of the tectum which is the dorsal part or serving as the roof of the midbrain and the tegmentum which is serving as the ventral part of the midbrain the tectum is composed of four folliculi or anatomically termed as the corpora quadrigemina the rostral colliculi are two rounded eminences containing visual reflex centers while the caudal colliculi are two rounded eminences behind the rostral colliculi containing auditory reflex centers next is the pons the pons is the bulge between the midbrain and the medulla oblongata bridging the spinal cord and the brain several other nuclei are situated within the ponds and are responsible for controlling motor functions of the body here is a ventral view of the brain to show the pawns the last part and the caudal most part of the brain is the medulla oblongata or commonly referred to as the medulla it continues caudally exiting at the foramen magnum as the spinal cord three vital reflexes are present in the medulla oblongata the cardiac center which regulates the rate and strength of the heart contraction the vasomotor center which regulates the diameter of the blood vessels and the respiratory center which regulates the rhythm of breathing that ends our discussion on the anatomy of the remaining parts of the brain like the diencephalon the cerebellum midbrain medulla oblongata and the pons it is important that at least you are familiar with their location in the brain as well as the structures present within them you may now proceed to the next part of this module which will discuss the anatomy of the other parts of the brain like the brain ventricles and the different layers of the brain managers