Brain 3 Medulla / pons / midbrain/ diencephalon

medulla oblongata is

ontinuous with the spinal cord to the brainstem

all communication between the brain and spinal cord passes through the

medulla oblongata

Nuclei in the medulla oblongata are:

▪ Relay stations for sensory or motor pathways

▪ Associated with cranial nerves connected to the medulla oblongata

▪ Associated with the autonomic control of visceral organs

Gracile nucleus and cuneate nucleus( Relay stations)

Pass somatic sensory information to the thalamus

Solitary nucleus ( Relay stations)

Receives visceral sensation from the spinal nerves and cranial nerves

Olivary nuclei ( Relay stations)

Pass information from the cerebrum, spinal cord, diencephalon, and brainstem

to the cerebellum

▪ The olivary nuclei create the olives (bulges on the medulla oblongata)

Reflex centers (Autonomic nuclei)

Receive input from cranial nerves, cerebral cortex, diencephalon, and brainstem

The pons is a

prominent bulge superior to the

medulla oblongata

The pons consists of

sensory and motor , involuntary control of breathing, and nuclei that relay cerebellar commands.

Mesencephalon is also called

Midbrain

Mesencephalon contains

pairs of nuclei collectively called

corpora quadrigemina

In midbrain Auditory processing occurs in

the

inferior colliculi

In midbrain Visual processing occurs in the

superior colliculi

The ventrolateral surfaces in midbrain contain

the

cerebral peduncles

Epithalamus

Contains the pineal

gland/produces melatonin

Thalamus

Left and right are connected

via the interthalamic

adhesion

Hypothalamus

Extends from the area superior

to the optic chiasm to the

mammillary bodies

Forms the walls of the third ventricle

The Thalamus

The Thalamus description

– There is a right and a left thalamus

– Thalamic nuclei are egg-shaped

Functions of Thalamic Nuclei: All 5

– Anterior nuclei: part of the limbic system

– Medial nuclei: relay information to the frontal lobe

– Ventral nuclei: relay information to the parietal lobes

– Posterior nuclei: relay information to the occipital lobe

– Lateral nuclei: adjust activity in the cingulate gyrus and parietal lobe

Functions of the Hypothalamus

Secretion of antidiuretic hormone (via the supraoptic nucleus) and oxytocin (via the paraventricular nucleus) , Body temperature (via

pre-optic area), and Circadian rhythm (via

suprachiasmatic nucleus)