Gross Neuroanatomy

Question 1

What is the role of astrocytes?

Answer 1

• Fill the space between neurons
• Regulate the chemical content of the extracellular space which could interfere with the function of the neurons.
• Migrate to sites of injury

Question 2

Role of Myelinating Glia (Oligodendrocytes & Schwann cells)

What can happen if these cells are damaged?

Answer 2

• Provide layers of membrane that insulate the axons.
• Damage = multiple sclerosis
  Axons become demyelinated and neurons begin to die. Dysarthria, swallowing difficulties and high level cognitive difficulties

Question 3

Soma (cell body)

Answer 3

• Integrative decision-making
• Filled with cytosol
• Contains DNA

Question 4

Cytoskeleton

and Disease of the Cytoskeleton

Answer 4

• Microtubules: transmitting messages from dendrite - axon
• Microfilaments:
• Neurofilaments: mechanically strong, hold axon together

Alzheimer’s disease - microtubules fall apart because Tau proteins (that hold microtubules together) detach and tangle.

Question 5

Axon

Answer 5

Very important role in information exchange:

- Releases neurotransmitter to synaptic cleft

Question 6

Dendrites

Answer 6

Receive message from synapse, transmit message to the cell body. Well connected neurons will have MANY dendritic spines

Question 7

Outermost protective layer

Answer 7

Dura mater - tough layer of fibrous tissue

Question 8

Middle protective layer

Answer 8

Arachnoid layer - thin sheet of connective tissue

Question 9

Innermost protective layer

Answer 9

Pia mater - moderately tough membrane that clings to the surface of the brain

Question 10

Differences between the CNS and the PNS

Answer 10

CNS is the brain and spinal cord. PNS is all other neural pathways in the body.

The PNS relays information to (sensory neurons) and from (motor neurons) the CNS.

Question 11

Divisions of the PNS

Answer 11

Somatic Nervous System - controls all VOLUNTARY body functions
Autonomic Nervous System - controls INVOLUNTARY functions e.g. breathing, heart rate, digestion.

Question 12

Divisions of the ANS

Answer 12

Sympathetic Division - “fight or flight” responses (increased heart rate, blood pressure etc)
Parasympathetic Division - “rest and digest” functions

Question 13

Cerebellum

Answer 13

“Little brain” at the rear base of cerebrum.

Controls the coordination of motor processes

Question 14

Brainstem

Answer 14

Controls important survival reflexes - heart rate, breathing, swallowing, sleep.

Question 15

What is the role of the frontal lobe?

Answer 15

Performs “executive” functions, such as decision-making.
Contains primary motor cortex
Motivation
Personality

Question 16

What is the role of the temporal lobe?

Answer 16

Interpreting sounds and language
Contains the primary auditory cortex
Memory (contains the hippocampus)

Question 17

What is the role of the parietal lobe?

Answer 17

Processing tactile sensory information

Contains the somatosensory cortex

Question 18

What is the role of the occipital lobe?

Answer 18

Interprets visual stimuli/information

Contains the primary visual cortex

Question 19

What connects the left and right hemispheres?

Answer 19

Corpus collosum - allows communication between the two hemispheres

Question 20

Structural changes characteristic of MS

Answer 20

Destroys myelin - therefore action potential slows/stops as it travels along the axon. Neuron eventually dies. Muscle weakness,

Question 21

Visual Neglect

Answer 21

Damage to the parietal lobe in the right hemisphere. Disrupts ability to pay attention to things on the left side of their visual field

Question 22

Frontotemporal Dementia

Answer 22

Overt change in the individual’s personality
Irritability, withdrawal, obsessions.
Often NO CHANGE TO MEMORY

Question 23

Which lobe enables us to recognise objects/faces by sight?

Answer 23

Temporal lobe

Question 24

Limitations of localisation theory

Answer 24

Too simplistic - many areas of the brain contribute to a single function (especially higher order cognitive functions).
- Localisation theory doesn’t fully explain the DIVERSITY of presentation of clients with damage to the same area