ANAT LEC Ch. 16 - The Brain & Cranial Nerves

CSF= CerebralSpinoFluid

Neurocoele

Neurocoele

• Hollow Neural tube

  • w/ fluid filled internal cavity

  • Enlarges to form ventricles

At week 4 (Human Baby) these EXPAND RAPIDLY

• Prosencephalon

• Mesencephalon

• Rhombencephalon

Prosencephalon

The Forebrain

• Divided forms Telencephalon (CEREBRUM) & Diencephalon

Mesencephalon

The Midbrain

• Processing of VISUAL & AUDITORY data

• Generates of Reflexive Somatic Motor responses

• Maintenance of Consciousness

• 2 pairs of SENSORY Nuclei

• Responsible for many INVOLUNTARY Muscle Responses

Rhombencephalon

The Hindbrain

• Divided forms the Metencephalon & Myelencephalon

Medulla Oblongata

Connects Brainstem to Spinal cord

Pons

Connects the cerebellum to the brainstem & contains:

• Sensory & Motor nuclei for Cranial Nerves 5-8

• Regulate REFLEX CENTER of the Medulla

• Nuclei process & relay CEREBELLAR Commands

• A/Descending & Transverse tracts

  • Interconnect pons to major brain areas

Cerebrum

Largest part of the brain, divided into paired hemispheres

Thalamus

Relay & processing center for Sensory info

Hypothalamus

Centers controlling Emotions, Autonomic functions, & Hormone production

• skeletal muscle contractions

• control autonomic funcs

• coordinates activities of nervous & Endocrine sys

• secretes hormones

• produces emotions & behavioral drives

• coordination b/w Voluntary & Autonomic funcs

• Regulation of body temp

• Controls Circadian rhythms

Meninges

Protect the brain as shock absorbers

• prevents contact w/Skull bones

• Continuous w/Spinal meninges

Blood Brain Barrier (BBB)

Prevent materials from DIFFUSING b/w cells

• ONLY LIPIDS can cross

4 Regions where BBB is DIFFERENT

• Portions of the HYPOTHALAMUS

• Capillaries of the PINEAL gland

• Capillaries of the CHOROID plexus

• Capillaries of the posterior PITUITARY

Cerebral Spinal Fluid

Choroid Plexus produces

3 types of Nuclei Functions in the MEDULLA

1. Relay stations & Processing centers

2. Nuclei of Cranial Nerves

3. Autonomic Nuclei

Relay Stations & Processing Centers Function:

Acesnding tracts synapse w/Sensory or Motor nuclei of Medulla

Autonomic Nuclei Func.

Regulates essential autonomic functions including

• Cardiovascular Center

  • Adjusts HR

• Respiratory Center

  • Sets basic rate of breathing

SUPERIOR Colliculi in the Mesencephalon

Receive VISUAL info from the LATERAL Geniculate

INFERIOR Colliculi in the Mesencephalon

Receive AUDITORY info from the Medulla

Diencephalon

• Keeps the sleep/wake cycle

• Made up of Epithalamus & Thalamus

Epithalamus

Contains the Pineal Gland

• Secretes hormone, MELATONIN

Thalamus

• Has most Nerve tissue in the Diencephalon

• Its nuclei provide integration & Relay Centers for sensory & motor pathways

• All ascending sensory info (not olfactory) synapse here

Proprioception

• Sense of self-movement, force, and body position

The cerebellum receives _____ from the SC