Ch. 15 Anatomy Lecture

Meninges

Underneath the cranium (skull): dura mater → arachnoid → pia mater

Dura mater

• Thickest and toughest layer of the meninges

• Two layers (contains superior sagittal sinus)

• Dura = durable!

Arachnoid mater

Arachnoid = spider web!

Subarachnoid space

Where cerebrospinal fluid (CSF) is found

Gray matter

Mostly cell bodies and dendrites

White matter

• Mostly axons

• Lighter color because of myelin (fat)

Cortex

• Gray matter on the surface of the cerebrum and cerebellum

• Densely packed with neurons (6 layers); most complex

Nuclei

• Collections of gray matter in the interior of the CNS

• Function: complex muscle movements, expression of emotions/behavior (esp. fear), and integration of information from multiple sensations

Tracts

Bundles of white matter that share a common origin and destination (ex. nucleus to nucleus)

Funiculi

Groups of tracts in specific locations within the spinal cord

Pathway

Interconnected sets of nuclei and tracts that connect the nervous system to tissues/organs

Ganglia

Collections of gray matter in the PNS

Nerves

Bundles of white matter in the PNS

Corpus Callosum

Piece of white matter that connects the cerebral hemispheres

Insular lobe (aka insula)

Central sulcus of the right hemisphere

Central sulcus of the left hemisphere

• Lateral fissure

• Below it is the insula

Parieto-occipital sulcus

Cortex of the frontal lobe

Function: primary motor cortex; higher intellectual functions; short-term memory

Cortex of the parietal lobe

Function: primary somatosensory cortex; perception of motion

Cortex of temporal lobe

Function: primary auditory and olfactory cortex; visual recognition of objects (esp. faces)

Cortex of occipital lobe

Function: primary visual cortex

Cortex of insula lobe

Function: primary gustatory cortex; interoception (awareness of visceral sensations)

Commissural tracts

Projection tracts

Association tracts

How do we visualize tracts?

Using specialized MRI; diffusion tensor imaging

Thalamus

• Made of multiple nuclei

• Each nucleus relays info to the appropriate area of the cerebrum

Hypothalamus

• Made of multiple nuclei

• Function: controls pituitary gland; control of autonomic motor commands; control of drives; regulation of body temperature; regulation of circadian rhythms

Pyramid

Olive

Brainstem

LOTS of nuclei

Midbrain

Function: involuntary eye movement; reflexes to visual/auditory info

Pons

Function: works with medulla to regulate breathing; relays info from cortex to cerebellum; REM sleep

Medulla oblongata

Function: regulates breathing, heart rate, digestion, sleep, blood vessel diameter; muscle tone/movement; reflexes; relays sounds and equilibrium info to thalamus

Cerebellum

Function: coordination of muscular movement; motor learning

Cerebrospinal fluid (CSF)

• Derivative of blood that fills the ventricles, the subarachnoid space, and around the spinal cord

• Produced by choroid plexus