Chapter 7: Studying the Brain's Structure and Functions

Question 1

Surgical techniques for treating Parkinson’s disease

Answer 1

• Deep-brain stimulation
• brain lesions

Question 2

Drug manipulations in rats

Answer 2

Hebb discovered by testing rats that…

• Cognitively stimulating environments help maximize intellectual development
• More enriched/complex environments -> more and larger synapses, more and larger astrocytes (rat study)
• Not more neurons but more neural mass
• One group of rats lived in the Hebb’s kitchen while the others grew up in a lab

Question 3

Hypokinetic vs hyperkinetic rats

Question 4

DREADD

Answer 4

• Designer Receptors Exclusively Activated by Designer Drugs
• to identify the circuitry and cellular signals that specify behavior, perceptions, emotions, innate drives, and motor functions
• Form of chemogenetics

Question 5

Electroencephalography (advantages/disadvantages)

Answer 5

• Records graded potentials from thousands of cells
• Reveals features of the brain’s ALWAYS ACTIVE electrical activity

Adv.
- the ability to see brain activity as it unfolds in real time, at the level of milliseconds (thousandths of a second).

Disadv.
- it’s hard to figure out where in the brain the electrical activity is coming from.
- Shallow depth

Question 6

Event related potentials

Answer 6

• the measured brain response that is the direct result of a specific sensory, cognitive, or motor event.
• EEG measures ERPs
• the response becomes more clear after repeated presentations of the stimulus

Question 7

Magnetoencephalography (advantages/disadvantages)

Answer 7

• The natural magnetic field produced as a byproduct of our natural electrical field from our brain is measured in the form of magnetic potentials

Adv.
- Permit a three-dimensional localization of the cell groups generating the measured field
- Higher resolution than ERP, goes deeper than EEG
- higher temporal resolution

Disadv.
- High cost

Question 8

Diffusion tensor imaging (advantages/disadvantages)

Answer 8

• Detects the directional movements of water molecules through white matter nerve fiber pathways in the brain

Adv.
- Used to delineate abnormalities in neural pathways

Disadv.
- Can’t differentiate between tissue types

Question 9

Magnetic resonance spectroscopy (advantages/disadvantages)

Answer 9

• MRI method that uses the hydrogen proton signal to determine the concentration of brain metabolites, such a N-acetylaspartate

adv.
- Useful in detecting persisting abnormalities in brain metabolism in disorders such as concussion

disadv.
- low sensitivity and spectral resolution

Question 10

Functional brain imaging techniques (advantages/disadvantages)

Answer 10

• When human brain activity increases, the increase in oxygen produced by increased blood flow actually exceeds the tissue’s need for oxygen

adv.
- good spatial resolution

disadv
- bad temporal resolution compared to EEG and ERP

Question 11

Twins relation to epigenetics

Answer 11

• Epigenetic changes can persist throughout a lifetime and even across multiple generations
• Chronic stress, traumatic events, drugs, culture, and disease are factors

Question 12

ERPs

Answer 12

• the graded potentials on dendrites that a sensory stimulus triggers
• Complex EEG waveforms are related in time to a specific sensory event

Question 13

Beta waves and related behaviors

Answer 13

• Low amplitude and fast
• Behavior: strongly engaged mind. A person in active conversation would be in beta

Question 14

Alpha waves and related behaviors

Answer 14

• High amplitude and slow
• Behavior: non-arousal, meditation, walking in a garden

Question 15

Theta waves and related behaviors

Answer 15

• Greater amplitude and slower frequency than alpha but less than Delta
• Behavior: has taken time off from a task and begins to daydream,

Question 16

Delta waves and related behaviors

Answer 16

• greatest amplitude and slowest frequency out of them all
• Behavior: deep dreamless sleep

Question 17

Optical tomography

Answer 17

example of functional resonance imaging