3.7 - Brain Pathways

Question 1

What functions does the frontal lobe have?

Answer 1

• Voluntary motor functions
• Speech
  -Consciousness

Question 2

What functions does the parietal lobe have?

Answer 2

• Touch sensation
• Understanding language

Question 3

What functions does the occipital lobe have?

Answer 3

• Vision sensation

Question 4

What functions does the temporal lobe have?

Answer 4

• Hearing sensation

Question 5

Where can the taste and smell sensations be found?

Answer 5

At junction between frontal and parietal lobes

Question 6

What regions are in the frontal lobe?

Answer 6

• Primary motor (tells a skeletal muscle to move)
• Association motor (stores patterns to activate the right muscles in the right order at the right time)

Question 7

What regions are in the parietal lobe?

Answer 7

• Primary touch sensory (feels that a touch/pressure/vibration/temperature change has happened)
• Association touch sensory (understands what that feeling is)

Question 8

What regions are in the occipital lobe?

Answer 8

• Primary visual (detects shapes and colours)
• Association visual (understands what those shapes and colours mean in context)

Question 9

What regions are in the temporal lobe?

Answer 9

• Primary auditory (detects frequency and volume)
• Association auditory (understands what collection of sounds means)

Question 10

What regions border the frontal and parietal lobes?

Answer 10

• Primary gustatory (detects chemicals associated with flavours)
• Association gustatory (links that taste with known substances)

Question 11

What regions border the frontal lobe and medial of temporal lobe?

Answer 11

• Primary olfactory (detects chemicals associated with scent)
• Association olfactory (links that scent with known substances)

Question 12

Which of the senses goes through the thalamus?

Answer 12

All sensory information is filtered by the thalamus EXCEPT FOR SMELL

• Gustatory, visual, auditory, somatosensory

Question 13

How does the thalamus filter stimuli?

Answer 13

• Thalamus “decides” if consciousness needs to be made aware of the feeling or not i.e. is it important to survival
• Thalamus then “allows” feeling to be forwarded to primary touch, primary visual, primary auditory, or primary gustatory cortex

Question 14

How is smell filtered?

Answer 14

• Smell NOT filtered by thalamus, goes directly from nose to primary olfactory (earliest memories from childhood linked to smell, method used by babies to identify “known” people i.e. parents)

Question 15

How does the prefrontal cortex help to filter sensory information?

Answer 15

Prefrontal cortex is the final destination where decisions are made once all information is understood

Question 16

What is the order of ‘decision’ pathway (AKA the route a stimuli takes)?

Answer 16

1) Thalamus receives sensory information and filters it

2) Important sensory information forwarded to appropriate primary cortex of cerebrum

3) Appropriate association cortex of cerebrum analyzes and contextualizes the information

4) Analysis forwarded to prefrontal cortex for decision of action

5) Action pattern retrieved from association motor cortex

6) Association motor cortex activates primary motor cortex to stimulate an effector

• All messages transmtited between sections via myelinated axons/white matter of the brain

Question 17

What is lateralization?

Answer 17

Lateralization = structurally, the left and right sides are mirror images of one another (though functionally they have diferent roles)

Left side of brain controls right sight of body and right side of brain controls left side of body

• Gets sensory info FROM opposite muscles/organs
  ** Sends motor info TO opposite muscles/organs

Question 18

In most people, which hemisphere is the most dominant?

Answer 18

Left hemisphere

• (Because most people are right handed)

Question 19

What are the chracteristics of Alzheimer’s?

Answer 19

-Specific proteins undergo changes and are released outside cells.
- These proteins gather together, leading to the death of nearby neurons.
- As time passes, various parts of the brain start to shrink.

Question 20

What are the characteristics of Parkinson’s?

Answer 20

• Involves aggregates of a protein for unknown reason, specifically in certain brain structures
• These structures (which also die) are responsible for releasing dopamine, and as a result, individuals with Parkinson’s have lower dopamine levels

Question 21

What are the characteristics of Huntington’s?

Answer 21

• Similar symptoms to Parkinson’s, but has a genetic cause
• Makes it useful to study for both Huntington’s AND Parkinson’s

Question 22

What are the characteristics of Multiple Sclerosis?

Answer 22

Results from the gradual destruction of oligodendrocytes (and therefore removal of myelin)

Question 23

What are the characteristics of Seizures?

Answer 23

Occur when there is excessive firing in certain neurons

Question 24

What are congenital defects?

Answer 24

Congenital defects are defects present from birth

Question 25

What is microcephaly?

Answer 25

Microcephaly is a medical condition characterized by a smaller than average head size for a person's age and sex. Microcephaly is often associated with underdevelopment of the brain. Individuals with microcephaly may experience intellectual disabilities, developmental delays, and challenges with motor functions.

Question 26

What are the primary causes of congenital defects?

Answer 26

- Genetic factors - Environmental factors (exposure to teratogens: alcohol/drugs) - Infections (ex: Zika Virus) - Radiation exposure