Brain physiology

Question 1

Layers of the head (8)

Answer 1

Skin
Periosteum
Bone
Dura mater
Arachnoid (fibrous membrane)
Pia mater
Gray matter
White matter

Question 2

Which 3 layers are bathed in CSF?

Answer 2

Dura mater, arachnoid, and pia mater

Question 3

Cerebrospinal fluid (CSF) is produced in…

Answer 3

the choroid plexus, located along the ventricles

Question 4

Functions of CSF (4)

Answer 4

1. Cushions the brain
2. Prevents pressure on the brain stem by keeping the brain floating in the cranium
3. CSF flow washes waste materials from the brain into the venous system
4. Helps maintain intercerebral pressure

Question 5

Flow of CSF

Answer 5

Bathing brain and spinal cord

Absorbed via arachnoid granulations in subarachnoid spaces into venous system

Question 6

Intracranial pressure is governed by…

Answer 6

Blood flow and CSF flow

Question 7

Cerebral perfusion pressure =

Answer 7

Mean arterial pressure - intracranial pressure, and is needed to force blood into the brain tissues
Therefore blood pressure needs to be greater than intracranial pressure (BP will adjust to this)

Question 8

Monroe-Kellie hypothesis

Answer 8

Increase in volume of one of the intracranial components (CSF, blood or brain) must be accopanied by a reciprocal decrease in another component

Question 9

Intracranial compliance is…

Answer 9

the relationship between changes in intracranial pressure and volume.
If compliance is low, small changes in volume can result in high increase in pressure

Question 10

Regions of the hind brain (3)

Answer 10

Medulla
Pons
Cerebellum

Question 11

Medulla

Answer 11

Connects spinal cord to pons
Centre of autonomic control
Homeostatic control
Respiratory and cardiovascular systems

Question 12

Pons

Answer 12

Bridges the cerebrum and the cerebellum

Relays movement signals from forebrain to cerebellum

Question 13

Cerebellum

Answer 13

Important in coordination and balance

Handles walking and posture

Question 14

Mid brain

Answer 14

Posture and walking
Reflexes of eye movement
Motivation and habituation
Input from the eyes and ears
Sensory input from the spinal cord

Question 15

Regions of the forebrain (2)

Answer 15

Telencephalon - cerebral cortex (frontal, temporal, parietal and occipital lobes), limbic system
Diencephalon - thalamus, hypothalamus

Question 16

Frontal lobe

Answer 16

Contains olfactory and motor cortices
Language production
Memory
Higher cognitive function

Question 17

Temporal lobe

Answer 17

Auditory processing
Memory
Understanding language

Question 18

Parietal lobe

Answer 18

Somatosensory
Spatial processing
Attention

Question 19

Occipital lobe

Answer 19

Vision
V1 - contrast
V2 - colour and shape
V3 - motion
V4 - colour
V5 - motion and eye movement

Question 20

Homunculus man

Answer 20

Each side of the central sulcus has a ‘map’ of the body for motor area (frontal cortex) and sensory area (parietal cortex)
Each hemisphere controls the opposite side of the body

Question 21

Wernicke’s aphasia

Answer 21

Can’t understand content words or produce meaningful sentences

Question 22

Broca’s aphasia

Answer 22

Can use content words but can’t form a grammatical sentence

Question 23

Limbic system

Answer 23

Emotion processing
Amygdala - fear, socialisation, mating
Hippocampus - short- and long-term memory and spatial orientation

Question 24

Thalamus

Answer 24

Primary ‘gate’ between sensory and motor neurons in the PNS and cerebral hemispheres in the CNS - directs signals to where they’re needed

Question 25

Hypothalamus

Answer 25

Main autonomic control centre after medulla; maintains homeostasis

Question 26

Corpus callosum

Answer 26

Nerve pathway between right and left hemispheres

Question 27

Basal ganglia

Answer 27

Contains globus pallidus, substantia nigra, thalamus, striatum and subthalamic nucleus
Substantia nigra - seat of anger and fear
Movement regulation
Skill learning
Glutamin excitatory pathways, dopamine inhibitory adn excitatory pathways, and GABA inhibitory pathways