Memory and Cognition Flashcards Preview

Systems: Neurology AB > Memory and Cognition > Flashcards

Flashcards in Memory and Cognition Deck (68)
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1
Q

What does cognition relate to?

A

The highest order of brain function and the behaviour that deals with thought processing.

2
Q

What does cognition describe?

A

The integration of all sensory information to make sense of a situation.

3
Q

What does making sense of something require?

A

An ability to remember events and learn from them

4
Q

What does learning and remembering require?

A

Motivation

5
Q

Neuronal plasticity

A

The ability of central neurons to adapt their neuronal connections in responses to learning experiences

6
Q

What is most of the cerebrum formed from?

A

Association areas

7
Q

What do association areas do?

A
  • Integrate information from multiple sources rather than being concerned with one specific function.
  • The brain can therefore be thought of as multiple parallel processing units
8
Q

What are the 3 key components of learning and memory?

A
  • Hippocampus
  • Cortex
  • Thalamus
9
Q

What role does the hippocampus play in learning and memory?

A

Formation of memories

10
Q

What role does the cortex play in learning and memory?

A

Storage of memories

11
Q

What role does the thalamus play in learning and memory?

A

Searches and accesses memories

12
Q

What does the limbic system do?

A

Gives events emotional significance which is essential for memory

13
Q

What are the 4 distinct areas of the limbic system?

A

-Cingulate gyrus: plays a role in emotion
-Hippocampus: associated with memory
-Amygdala: associated with emotion
Hypothalamus: associated with AMS responses

14
Q

What does the limbic system represent?

A

The old cortex

15
Q

What does the limbic system have connections with?

A

The neo cortex in particular the temporal and frontal lobes which allow us to make sense of situations through learning.

16
Q

What is the most primitive part of the cortex?

A

Limbic system

17
Q

Collectively, what are the 4 areas of the limbic system responsible for?

A
  • Instinctive behaviour like thirst, hunger and sex

- Emotion behaviour driven by seeking reward or avoiding punishment

18
Q

What are reward areas?

A

Electrical stimulation in these areas of the brain in conscious patients will elicit intense feelings of well being, euphoria and sexual arousal

19
Q

What are punishment areas?

A

Electrical stimulation in these areas of the brain in conscious patients will elicit feelings of terror, anger or pain

20
Q

What do reward and punishment areas form?

A

Affective components of sensory experiences

21
Q

Where does motivation to learn come from?

A

Gaining a reward or avoiding a punishment which gives the task significance

22
Q

What drives almost every conscious thing we do?

A

Reward and punishment

23
Q

What is barely remembered?

A

Experiences that are neither rewarding or punishing

24
Q

What does your brain naturally five attention to?

A

Experiences it deems significant

25
Q

What assesses the significance of an event?

A

The frontal cortex and its association with the reward/punishment centres in the limbic system

26
Q

If something is deemed insignificant what happens to it?

A

It is forgotten

27
Q

Where does nearly all sensory information go through?

A

Hippocampus

28
Q

What does the hippocampus do to sensory information it receives?

A

Relays information to other limbic system structures

29
Q

What do people with bilateral hippocampal damage have?

A
  • Immediate (sensory) memory (seconds in length) and intact long term memory ( from time before damage) but are unable to form new long term memories
  • Their reflexive (motor skills) remain intact
30
Q

Immediate or Sensory memory

A
  • Few seconds
  • Describes the ability to hold experiences in the mind for a few seconds.
  • Based on different sensory modalities
  • Visual memories decay fastest (<1s), auditory slowest (<4s)
31
Q

Short-term memory

A
  • Seconds-hours
  • Often called working memory
  • Brain’s post it note
  • Used for short term tasks such as dialling a phone number, mental arithmetic, reading a sentence
  • Associated with reverberating circuits
32
Q

Long-term memory

A
  • Can be lifelong
  • Where you grew up and your childhood friends
  • Associated with structural changes in synaptic connections
33
Q

Intermediate long-term memory

A
  • Hours to weeks
  • What you did last weekend
  • Associated with chemical adaption at presynaptic terminal
34
Q

Which type of memory is associated with electrical phenomenon?

A

Short-term

35
Q

What does short-term memory depend on?

A

Maintained excitation from reverberating circuits

-They constantly need to refreshed

36
Q

What is each synapse in a reverberating circuit?

A

-Excitatory hence a brief excitatory stimulus will cause a long lasting neuronal activity as the reverberating circuit neurons continue to excite all neurons in the pathway

37
Q

What happens if a short-term memory is deemed significant?

A

Eventually the reverberation will result in consolidation of the memory in long term memory storage

38
Q

What happens if a short-term memory is deemed insignificant?

A

The reverberation fades and no consolidation occurs

39
Q

What may disrupt reverberation?

A
  • Head injury

- Infection

40
Q

What happens if reverberation is disrupted?

A

Memory loss normally results especially if it involves the hippocampus and/or the thalamus

41
Q

Amnesia

A

Memory loss

42
Q

Anterograde amnesia

A
  • Inability to form new memories
  • Inability to recall events that happen after the injury
  • Depending on the severity of the injury it can be short lived or permanent
43
Q

Retrograde amnesia

A
  • Inability to access (more recent) old memories
  • Can’t remember events leading up to the injury although recall of vents that happened a long time ago is usually unaffected, probably because they are better rehearsed and more deeply ingrained
44
Q

What will destruction of the hippocampus result in?

A

Inability to form new memories

45
Q

What does retrograde amnesia often present with?

A

Anterograde

46
Q

What occurs if the thalamus is damaged but not the hippocampus?

A

Retrograde amnesia

47
Q

What does memory require?

A

The ability to form, store and search for our memories

48
Q

How is intermediate long-term memory established?

A
  • Involves chemical changes in presynaptic neurons

- Increasing Ca entry to presynaptic terminals, increases neurotransmitter release

49
Q

What structural changes at synapses are involved in long-term memory?

A
  • Increase in NT release sites in presynaptic membrane
  • Increase in number of NT vesicles stored and released
  • Increase in number of presynaptic terminals
  • Increase in number of presynaptic terminals
50
Q

What is long term potentiation?

A
  • Basically a well established, well rehearse pattern of neuronal firing unique to that particular memory
  • Increased amplitude in graded membrane potential in the post-synaptic cell
  • Strengthens the synapse
  • Forms the basis of much learning and memory
51
Q

What are the 2 main types of long term memory?

A
  • Declarative or explicit memory

- Procedural/reflexive/implicit memory

52
Q

Declarative or explicit memory

A
  • Abstract memory for events (episodic memory) and for words, rules and language (semantic memory)
  • Is based mainly in the hippocampus
53
Q

Procedural/reflexive/implicit memory

A
  • Acquired slowly through repetition
  • Includes motor memory for acquired motor skills such as playing tennis and rules based learning such as driving on the left in the UK
  • Thinking about these skills (memories) often impairs performance
  • Is based mainly in the cerebellum
  • Is independent of hippocampus
54
Q

How is short-term memory converted to long-term memory?

A

Through consolidation

55
Q

What does consolidation involve?

A

Selective strengthening of synaptic connections through repetition (for minutes to hours)

56
Q

Where do similar process to consolidation for motor learning take place?

A

Cerebellum

57
Q

How does memory exist during consolidation?

A

It exists as electrical activity and is vulnerable to being wiped out

58
Q

What does consolidation require to be effective?

A

Attention

59
Q

Why doe you sometimes see something that isn’t really there like faces on cars or fruit?

A
  • New memories are coded then stored in the sensory and association areas of the cortex.
  • Coding results in new memories being stored alongside other existing memories the brain deems similar
60
Q

If an experience is considered useful what does the frontal cortex do?

A

It gates the Papez circuit

61
Q

What are the 4 components of the Papez circuit?

A
  • Hippocampus
  • Mammillary bodies
  • Anterior thalamus
  • Cingulate gyrus
62
Q

Where does reverberation take place until consolidation is established?

A

Between the Papez circuit, the frontal cortex, the sensory and association areas

63
Q

How are different components of the memory laid down?

A

In different parts of the cortex

  • Visual component in the visual cortex
  • Auditory component in the auditory cortex
64
Q

Why are smells especially powerful in evoking long term memories?

A
  • Olfactory stimuli are relayed from the olfactory tract through the amygdala and hippocampus to the prefrontal cortex where they can be acknowledges.
  • The route through the limbic system and hippocampus helps in evoking long term memories.
65
Q

Korsakoff’s syndrome

A
  • Chronic alcoholism
  • Vitamin B1 deficiency which leads to damage of limbic system structures
  • The ability to consolidate memory is impaired
66
Q

Alzheimer’s disease

A
  • Severe loss of cholinergic neurons throughout the brain, including the hippocampus
  • Gross impairment of memory
  • Some improvement in Alzheimer’s may be seen with anti-cholinesterase’s but underlying degeneration continues
  • Cause unknown
67
Q

REM Sleep

A
  • Important for memory
  • Subjects deprived of REM sleep show significant impairment of memory consolidation for complex cognitive tasks.
  • Dreaming may enable memory consolidation, reinforce weak circuits
  • Patients with Korsakoff’s syndrome or Alzheimer’s have greatly reduced REM sleep
68
Q

What type of memories are we born with?

A

Inherited memories essential for survival