The Brain - Chapter 2 Content

Question 1

Describe the hindbrain

Answer 1

The section of the brain contains three structures:
1. Medulla oblongata - transmitting info from the spinal cord to the brain, regulating life support
2. The pons - crossing over of info from the right side to the left side of the body, balance, processing visual/auditory info
3. Cerebellum - coordinates muscular activity, motor behaviour/coordination

Question 2

Describe the midbrain

Answer 2

The structure involved is in control of relaying info between the cerebellum and forebrain. The reticular formation helps keep us awake and alert, involved in sudden arousal.

Question 3

Describe the forebrain

Answer 3

1. thalamus - relaying info to the cerebral cortex
2. hypothalamus - controls the pituitary gland by releasing hormones, controls homeostatic behaviours such as drinking, temp control
3. hippocampus - formation of long-term memories
4. amygdala - modulates strong emotional memories, emotional learning

Question 4

What are all the subcortical structures of the brain?

Answer 4

Thalamus (switching station for sensory info), hypothalamus, hippocampus, amygdala, cerebellum, medulla oblongata, spinal cord (transmit signal from the brain to rest of body)

Question 5

What is the cerebral cortex?

Answer 5

It consist of 6 layers of neurons with white matter beneath, carrying info between the cortex and thalamus or different parts of the cortex.

Question 6

What are the 4 lobes?

Answer 6

Frontal (under forehead), parietal (under the top rear part of skull), occipital (back of head), temporal (side of head)

Question 7

How are the two halves of the brain connected and separated?

Answer 7

They are connected via the corpus callosum and divided by the central sulcus.

Question 8

Explain the parietal lobe

Answer 8

This contains the somatosensory cortex, with the postcentral gyrus (mountain on the brain). This area is involved in processing sensory info like touch, pain, pressure, etc. Also important for language and mathematical processing.

Question 9

Explain the temporal lobe.

Answer 9

The temporal lobe is known for its auditory processing (like recognizing someone’s face). Damage to the temporal can cause loss of memory as it is located near the amygdala and hippocampus.

Question 10

Explain the frontal lobe.

Answer 10

The lobe has 3 regions: motor (directs fine movement) primary motor (planning movement), prefrontal (executive functioning = planning, decision making, strategies, using working memory)

Question 11

What is localization?

Answer 11

This is the mapping of the brain, related to phrenology (studying how brain size affects function capabilities)

Question 12

What is aphasia?

Answer 12

It is the disruption of expressive language. There is Broca’s area, where someone is unable to speak fluently but can comprenhend. Wernicke’s area is where someone produces speech very fluently but it makes no sense, almost gibberish.

Question 13

What is the primary somatosensory cortex?

Answer 13

Each part receives info from a certain part of the body

Question 14

Explain what neuroplasticity means.

Answer 14

It explains how some regions of the brain can take over the functioning of damaged regions. Neurons are able to expand and do different things.

Question 15

Explain what lateralization means.

Answer 15

Understanding that the two hemispheres play different roles when it comes to certain cognitive functions, especially language

Question 16

What is a CAT scan?

Answer 16

Highly focused X-ray beams are passed through the body from different angles and visualisation of the organ can occur.

Question 17

What is an EEG?

Answer 17

This is used to detect different states of consciousness with metal electrodes placed all over the head. Waveforms record changes in ways to know when neurons are firing and leaving an electrical charge. This has a very good temporal resolution as it can tell exactly when something is happening with the electrical movement in the brain but is poor spatial as it cannot tell you where the electrical activity is.

Question 18

What is an ERP?

Answer 18

The event-related potential is to measure the area of the brain responding to a specific event. Brain activity is recorded from before to after the stimulus.

Question 19

What is a PET scan?

Answer 19

This is by injecting radioactive label compounds to measure the blood flow to different regions when they are the most active.

Question 20

What is a MRI?

Answer 20

An MRI provides info about blood flow and such but without radiation and creates cleared pictures than a CAT scan. MRI uses a strong magnetic field and radio waves are directed at the head.

Question 21

What is an fMRI?

Answer 21

This kind relies on the fact that the blood has magnetic properties. Brain regions that become active show a change in deoxygenated to oxygenated blood which is known as cerebral blood flow. This has good spatial resolution and is can see where it will happen but bad temporal as it happens slowly.

Question 22

What are the key differences between all the different types of scans?

Answer 22

CAT and MRI scans get neuroanatomical info, PET and fMRI provide info about blood flow, and MEG, EEG and ERP all measure electrical activity.

Question 23

What is the field of metacognition?

Answer 23

This field is about thinking how people think and how you cannot always rely on people’s insights to guide you.

Question 24

What are the 2 main objective-dependent measures for behaviour?

Answer 24

Accuracy (seeing how well people can hold onto info) and reaction time (when accuracy is perfect, having harder tasks to see the difference in events over time in their head)

Question 25

Describe what subtractive logic is.

Answer 25

A subject is given one easy task and one more complex task (where a decision is needed to be made), and the reaction time from both of these are measured and then the complex - simple = difference. This difference is known as the decision time, as it is the amount of time the person took to make a more complex decision for the task.

Question 26

What are the 2 main measures used for the behaviour of modified brains?

Answer 26

Brain damage is used with examples such as Phineas’ gage and split brain. The other is TMS, which is when you are able to look at the brain when a specific region is stimulated.

Question 27

What are the two approaches used for naturally occurring/surgical brain lesions?

Answer 27

1. Look at a group of people with similar lesions to see what similar deficits they are experiencing.
2. Look at a group of people with similar cognitive impairment to see what similar brain regions they are not using.

Question 28

What are the 4 planes to look at a brain?

Answer 28

Axial (horizontally in the middle), Coronal (vertically in the middle where ears are), Sagittal (vertically down the middle but can be anywhere down the face), Midsagittal (directly down the middle vertically between eyes)

Question 29

What is the corpus callosum?

Answer 29

It is dense of neuro fibres and communicates both sides of the hemispheres together.

Question 30

What is important about the amygdala and the hippocampus?

Answer 30

The amygdala allows us to hold emotions to memories and the hippocampus is there to help us find specific memories scattered around the brain.

Question 31

What is the occipital lobe?

Answer 31

This lobe is primarily focused on vision as it is responsible to vision and colour perception. This does visual process and some basic movements as well.

Question 32

What is a trend that is seen with the level of complexity in the brain?

Answer 32

We notice that coming from the occipital lobe to the frontal lobe, the ability of the brain becomes stronger and allows us to do more complex things.

Question 33

What is faculty psychology?

Answer 33

The theory was about how different mental abilities were independent and that all functions were carried out in a specific part of the brain. This is also part of the Phrenology field.

Question 34

What are the 2 types of brain imaging meant for looking at the neuronal activity?

Answer 34

ERP and EEG

Question 35

What are the 2 types of brain imaging meant for looking at the metabolism of the brain?

Answer 35

PET and MRI

Question 36

How is subtractive logic used for brain imaging techniques?

Answer 36

It is calculated the same way but the difference this time is more so used to localize the function and to see where the highly complex tasks are completed in the brain.

Question 37

What is cerebral blood flow?

Answer 37

As neuronal activity increases, so does blood flow. fMRI depends on this signal difference in te magnetic properties of oxygenated and de-oxygenated blood.

Question 38

What is BOLD?

Answer 38

BOLD stands for blood oxygenation level dependent. This is how an MRI measures brain activity very slowly.