Unit 1: Intro and Brain Gross Anatomy Objective

Sagittal plane

Separates the body into left and right sides.

Transverse plane

Separates the body into superior and inferior halves.

Coronal (frontal) plane

Separates the body into anterior and posterior halves.

Which axis moves the sagittal plane

transverse axis

Which axis moves the transverse plane

longitudinal axis

Which axis moves the frontal plane

sagittal axis

Functions of cerebrospinal fluid (CSF) function

Protect the brain and spinal cord from trauma

Supply nutrients to the CNS

Remove waste products from the CNS

What is a choroid plexus

A network of blood vessels and cells in the brain that produce cerebrospinal fluid.

Location of choroid plexus

Third ventricle

Fourth ventricle

Lateral ventricle

Location of lateral ventricles

Located in each of the cerebral hemispheres.

Location of third ventricle

Cavity within the diencephalon.

Location of fourth ventricle

Posterior to pons and anterior to cerebellum.

What is the flow of CSF starting in the lateral ventricles to the central canal

CSF is secreted by choroid plexus in each lateral ventricle -> CSF passes through the interventricular foramina of each lateral hemisphere into the third ventricle -> choroid plexus in the third ventricle adds more CSF -> CSF flows down the cerebral aqueduct to the fourth ventricle -> choroid plexus in the fourth ventricle adds more CSF -> CSF either flows out to fill the subarachnoid space or it travel down the central canal

Hydrocephalus in infants

A condition caused by impaired circulation and removal of cerebrospinal fluid, leading to distortion of the brain and enlargement of the cranium.

Methods of protection for the brain

Bones of the skull

Cranial meninges

CSF

Blood brain barrier

Dura mater

Outermost layer, thick connective tissue made of collagen.

Arachnoid mater

Middle 'web-like' layer.

Pia mater

Surface of the CNS.

Blood brain barrier

Helps regulate chemical environment; anything fat soluble can cross.

Longitudinal fissure

Separates the left and right hemispheres.

Transverse fissure

Separates the cerebrum from the cerebellum.

Central sulcus

Separates the frontal and parietal lobes.

Lateral sulcus

Separates the temporal and frontal lobe.

Precentral gyrus

Primary motor area, anterior to the central sulcus.

Postcentral gyrus

Primary somatosensory area; posterior to the central sulcus.

Primary motor area

anterior to the central sulcus, initiates voluntary movements by sending signals to the muscles

Primary somatosensory area

posterior to the central sulcus, detects and processes sensory information from the body, such as touch, temperature, pain, and body position

Premotor area

anterior to the primary motor area and contains motor programs, sends information to the motor area

Motor programs

"muscle memory", complex muscle actions you do not need to think about (running, walking upstairs)

Primary somatosensory association area

Interpretation of sensory stimuli

Broca's area

Location in the lower anterior area of the premotor area; functions in planning speech

Temporal lobe

hearing and smell

Occipital lobe

vision association cortex

Frontal lobe

planning, decision making, problem-solving, judgement, attention

Parietal lobe

sensory processing

Commissures

left and right communication

Association fibers

anterior and posterior communication

Projection fibers

superior and inferior communication

White matter

transferring

Grey matter

processing

Basal nuclei

controls starting, stopping, and intensity of motor movements, inhibits antagonistic muscles during movements

Huntington's disease and basal nuclei

Degeneration of the basal nuclei causes people to lose the neurons responsible for regulating movements so they may drop things or lose the ability to properly aim their movements

Function of diencephalon

Connects the cerebrum to the brain stem both structurally and functionally

Function of thalamus

relays information

Function of hypothalamus

coordinates the nervous system and endocrine systems; regulates body temperature, thirst, hunger, sex drive, basic emotions, endocrine system, autonomic nervous system

Parts of the brain stem

contains midbrain, pons, and medulla oblongata

Function of midbrain

Contains centers for startle reflexes

contains the Substantia Nigra

Pathway for communication between lower and upper brain function

What is the corpora quadrigemina

Four bumps called colliculi on the dorsal surface of the midbrain

Function of superior colliculi

visual startle reflex

Function of inferior colliculi

auditory startle reflex

Location and function of the pons

the large bulb looking structure on the anterior portion of the brainstem; helps regulate respiration, helps coordinate involuntary skeletal muscle movements and muscle tone, relays information to and from the brain/spinal cord

Location and function of the cerebellum

posterior and inferior to the cerebrum; adjusts the postural muscles of the body to maintain balance, programs and fine-tunes (smooths) voluntary and involuntary movements

Location and function of medulla oblongata

inferior to the pons; physically connects the brain with the spinal cord, contains cardiovascular and respiratory centers, relay station, house for cranial nerve nuclei, controls blood pressure, breathing, and heart rate

Location of medullary pyramids

Ridge like structures running the length of the medulla oblongata on the ventral side