Complex functions of the brain

Question 1

Which three components show a rhythmic pattern of roughly 24 hours?

Answer 1

Body temperature
Growth Hormone
Cortisol

Question 2

What is the name of the photopigment found in the photosensitive retinal ganglion cells

Answer 2

Melanopsin

Question 3

What is considered the “master clock”

Answer 3

The suprachiasmatic nucleus of the hypothalamus

Question 4

Which brain waves are characteristic in stage 1 NREM sleep?

Answer 4

Theta Waves

Question 5

Descent into stage 2 NREM sleep is characterised by:

Answer 5

10-12Hz oscillations = sleep spindles

Question 6

Brain waves characteristic of stage Stage 3&4 NREM sleep

Answer 6

Delta Waves

Question 7

Brain waves characteristic in REM sleep

Answer 7

Alpha Waves

Question 8

Brain oxygen use in REM vs awake

Answer 8

Brain oxygen use: REM > awake

Question 9

What is narcolepsy

Answer 9

REM sleep attacks - people enter REM sleep from wakefulness during the day

Question 10

What is a possible cause of narcolepsy?

Answer 10

Mutation in the orexin receptor gene (Orx2) – hyperexcitability of neurons that generate REM sleep

Question 11

Define Memory

Answer 11

persistence of learning over time through the storage and retrieval of information

Question 12

What are the 3 gross stages of memory:

Answer 12

1 - Encoding (orregistration): receiving, processing & combining information
2 - Storage /consolidation: creation of a permanent record of encoded information
3 - Retrieval (recall or recognition): calling back of stored information in response to some cue

Question 13

Temporal Classifications of memory

Answer 13

1 - Immediate Memory: Ability of brain to hold onto ongoing experience
2 - Short Term memory: (working memory)
3 - Long term memory: storage of information over an extended period

Question 14

Types of LTM

Answer 14

Declarative (explicit) Memory - info that is explicitly stored & involves conscious effort to be retrieved
Non-declarative (Implicit Memory/ procedural) - collection of non-conscious knowledge systems provide capacity of skill learning, habit formation, phenomenon of priming

Question 15

Approaches led to us understanding structures involved in memory formation & maintenance

Answer 15

• Imaging studies (fMRI/PET scans)
• Lesion studies
• Karl Leshley
• Pathological & brain injury studies
• Patient HM

Question 16

Brain region underlying declarative memory acquisition & storage

Answer 16

Hippocampus & adjacent medial temporal lobe structures

Question 17

Brain areas underlying nondeclarative memory storage & acquisition

Answer 17

Basal ganglia, prefrontal cortex, amygdala, sensory association cortices & cerebellum

Question 18

Role of the hippocampus in LTM:

Answer 18

• Encoding & consolidation of new declarative memories
• Key to navigation/spatial memory
• Project info to cortical areas for storage to give meaning & make connections w other memories: The catalyst for LTM
  (but the memory engram is in various places in the cortex)

Question 19

What is Huntington’s

Answer 19

Atrophy of caudate & putamen - perform poorly on motor skill learning tests

Question 20

LTM storage a variety of cortcial sites:

a) site for meaning of words
b) site for memories of objects & faces

Answer 20

a) Wernicke’s area

b) Temporal cortex

Question 21

Anterograde Amnesia

Answer 21

The inability to establish new memories following neurological insult

Question 22

Retrograde Amnesia

Answer 22

Difficulty retrieving memories established prior to the precipitating neuropathology

Question 23

Effect of age on memory

Answer 23

1) Decrease in brain mass (volume) - shrinkage of frontal lobe & hippocampus
2) Decrease in synaptic connections/cortical density - reduced synaptic connections in cortex & deterioration of memory engrams
3) Reduction in the production of chemical messengers - reduction in NTs (dopamine) & reduction in neuroprotective hormones (eostrogen)
4) Decreased blood flow to the brain - impair memory & lead to changes in cognitive skills

Question 24

Dementia

Answer 24

A syndrome characterized by failure of recent memory & other intellectual functions

Question 25

3 principle features of AD (Alzheimer's Disease)

Answer 25

1) Neurofibrillary tangles: abnormal accumulations of protein (tau) collects inside of neurons 2) Amyloid plaques: aggregates of misfolded proteins that form in the spaces between nerve cells 3) Diffuse Neuronal loss: neural loss in brain regions such as hippocampus & prefrontal cortex (essential memory formation & executive functioning)

Question 26

Types of AD:

Answer 26

1 - Early onset AD: due to mutation on chromosome 21; mutation of amyloid precursor protein (APP) 2 - Late onset AD: pathological deposition of amyloid beta peptide; found ApoE protein (molecule that chaperoned cholesterol in bloodstream) & association w chromosome 19 in the same region as the gene that encodes for isoform of ApoE is located

Question 27

Mild Cognitive Impairment

Answer 27

Minor problems w cognitive function affecting mental abilities such as memory & thinking (not sever enough to classify as dementia)

Question 28

Encephalopathy

Answer 28

Disease that affect the function/structure of the brain - may include infections, toxins, drugs. Symptoms - progressive loss of memory & cognitive ability, subtle personality changes, inability to concentrate, lethargy, progressive loss of consciousness

Question 29

Traumatic Brain Injury (TBI)

Answer 29

Disruption in normal function of the brain caused by blow, jolt to head or violently hitting an object Symptoms - attention & concentration problems, trouble thinking clearly, problems with ST & LTM Common in athletes - chronic TBI linked to increased suicide rates