Chapter 5: Memory

Question 1

Memory

Answer 1

• An active process that encodes, stores and retrieves information acquired through learning when required
• Described as the neurological representation of learning

Question 2

Encoding, storage and retrieval

Answer 2

• Encoding – conversion of info into a usable form so that it can be neurologically represented and stored in memory
• Storage – retention of encoded information over time
• Retrieval – recovery of stored information and bringing it into conscious awareness for use

NOTE: Encoding occurs in both short-term and long-term memory.

Question 3

Atkinson–Shiffrin multi-store model

Answer 3

• Represents and explains memory as consisting of three components: sensory, short-term and long-term
• Each component differs in function, capacity and duration, however, they interact and operate simultaneously

Question 4

Attention, rehearsal, encoding and retrieval

Answer 4

• Attention: sensory → STM
• Rehearsal: STM → STM
• Encoding: STM → LTM
• Retrieval: LTM → STM

Question 5

Sensory memory

2 types: iconic and echoic

Answer 5

• Briefly stores new incoming sensory info in its orginal state
• Enables us to perceive the world around us as continuous
• Capacity: vast, potentially unlimited
• Duration: 0.2-4 seconds (cannot be extended)

Question 6

Iconic and echoic memory

Answer 6

• Iconic – stores visual sensory information
  
  • Capacity: unlimited
  • Duration: about 1/3 of a second
• Echoic – stores auditory sensory information
  
  • Capacity: unlimited
  • Duration: about 3-4 seconds

Question 7

Short term memory (STM)

‘Working memory’

Answer 7

• Temporarily stores a limited amount of info that is being consciously attented to & actively manipulated
• Contains information from both sensory and LTM
• Capacity: 7 ± 2 items
• Duration: up to about 30 seconds (longer if renewed)

Question 8

Chunking

Answer 8

• Grouping separate pieces of info into larger ‘chunks’
• Increases the capacity of STM

Question 9

Decay and displacement

STM

Answer 9

• Decay – when information is not renewed (e.g. via maintenance rehearsal) and is forgotten over time
• Displacement – pushing old items of info out when new info is introduced, given that STM is at maximum capacity

Question 10

Maintenance and elaborative rehearsal

Answer 10

• Maintenance – repeatedly saying or thinking about info to prevent decay; keeps info in STM
• Elaborative – encodes new info (makes it more meaningful) by linking it to info already held in LTM

NOTE: Elaborative rehearsal is more effective at transferring info to LTM.

Question 11

Long term memory (LTM)

2 types: explicit and implicit memory

Answer 11

• Stores info for re-access and use at a later time
• Some information can be lost or inaccessible over time
• Capacity: potentially unlimited
• Duration: very long time (possibly permanently)

Question 12

Explicit memory

‘Memory with awareness’ or ‘declerative memory’

Answer 12

• LTM that can be consciously retrieved and stated
• Divided into episodic and semantic memory
• E.g. your birthday party, identifying a dog breed

Question 13

Episodic memory

Answer 13

• Long-term explicit memory of personal experiences associated with a particular time and place
• E.g. remembering what you had for breakfast this morning

Question 14

Autobiographical memory

Answer 14

• Consists of episodes recollected from one’s life; based on a combination of episodic and semantic memories
• E.g. memory of the first day at school can include meeting the teacher (episodic) and the knowledge that the teacher’s name was Ms Smith (semantic)

NOTE: It is a type of explicit memory.

Question 15

Semantic memory

Answer 15

• Long-term explicit memory of facts and knowledge
• Does not include details of time and place
• E.g. meaning of words, rules, concepts, areas of expertise

Question 16

Implicit memory

‘Memory without awareness’ or ‘non-declarative memory’

Answer 16

• LTM that does not require conscious retrieval
• Divided into procedural and CC memory
• E.g. driving a car, brushing your teeth, fears, taste aversions

Question 17

Procedural memory

Answer 17

• Long-term implicit memory of skills that have been learned previously (often difficult to put into words)
• Often include motor or muscle memories
• E.g. using chopsticks, riding a bike, knowing how to read

Question 18

Classically conditioned memory

Answer 18

• Long-term implicit memory of conditioned responses particularly those involving fear or anxiety
• E.g. Little Albert’s fear of white rats, feeling nauseous at the sight of oysters (taste aversions)

Question 19

Hippocampus

Answer 19

• Deep in the medial temporal lobe + part of limbic system
• Forms, encodes and consolidates new explicit memories
• Transfers consolidated memories to neocortex for LT storage
• Does not store memory itself in the long term
• Also important for spatial memory (physical location of objects in space) which enables us to learn and remember locations
• Essential for consolidation of episodic / autobiographical mem

NOTE: We have one in each cerebral hemisphere.

Question 20

Damage to the hippocampus

Answer 20

• No new explicit memories can be formed
• No information can be passed from STM to LTM
• Leading contributor to Alzheimer’s disease

Question 21

Consolidation

Answer 21

• The neurobiological process of making a newly formed memory stable and enduring after a learning experience
• Once consolidated, memories are not necessarily fixed (open to reconsolidation)

Question 22

Amygdala

Answer 22

• Next to the hippocampus in the medial temporal lobe
• Processes and regulates emotions (particularly fear and anger) and forms and consolidates emotional memories
• Involved in the formation of classically conditoned fear responses involving implicit memory (e.g. Little Albert)
• Does not permanently store emotional memories

NOTE: We have one in each cerebral hemisphere.

Question 23

Damage to the amygdala

Answer 23

• No acquisition of CC fear responses
• No memory of emotional elements of explicit memories

Question 24

How does the amygdala enhance memory?

Answer 24

• Adds emotional context to explicit memories and works w the HC to ↑ consolidation of emotional events
• Emotionally arousing events are more memorable
• Increased adrenaline and noradrenaline in the amygdala during emotional arousal is believed to signal the HC

Question 25

Flashbulb memory

Answer 25

• Vivid and long lasting memory of an emotionally arousing event (often including specific details)
• E.g. someone remembering details about where they were and what they were doing when told about the death of a loved one

Question 26

Neocortex

Answer 26

• Wrinkly outer surface of the brain which is the largest & most recently evolved part of the brain
• Stores explicit mems after encoding + transfer by HC
• Memory is distributed throughout it
• Stores motor and CC responses
• Retrieves episodic, autobiographical and semantic info

NOTE: The terms cortex, neocortex and cerebral cortex are used interchangeably.

Question 27

Damage to the neocortex

Answer 27

• Damage to a particular part of the cortex is likely to affect the specific function performed by that region
• E.g. damage to the the right frontal lobe would cause difficulty retrieving episodic memories

Question 28

Basal Ganglia

Answer 28

• Group of structures (nuclei) deep within the brain
• Encodes and stores implicit mems involving motor skills associated with voluntary movements
• Also plays a role in habituation

Question 29

Habituation (basal ganglia)

Answer 29

• Growing accustomed to a situation/stimulus (involves reduced responsiveness following repeated exposure)
• Typically occurs without conscious awareness, thus, memories based on habitutation are considered implicit
• E.g. people living on main roads become habituated to the noise of passing traffic

Question 30

Damage to the basal ganglia

Answer 30

• Can be damaged by Parkinson’s and Huntington’s disease
• Impairs voluntary movements (e.g. tremors, difficulty walking and coordinating muscle movement)
• Medication that restores basal ganglia dopamine can improve acquisition and retention of simple motor tasks

Question 31

Cerebellum

Answer 31

• Located at the base of the brain
• Encodes and coordinates implicit, procedural memories of fine muscle movements (involving posture, balance, timing, speed, ease and fluency)
• Stores simple CC responses e.g. blinking in response to a CS

Question 32

Damage to the cerebellum

Answer 32

• Impaired timing and coordination of muscle control
• No acquisition of CC reflexes e.g. eye blink response

Question 33

Alzheimer’s disease

Answer 33

• Neurodegenerative disorder involving widespread degeneration of brain neurons which causes ↓ memory and cognitive / social skills + personality changes
• Initially affects STM more than LTM
• Accounts for around 70% of dementia cases
• Can only be confirmed via an autopsy (post-mortem)
• ↓ ability to retrieve long-term memories of autobiographical events and undergo episodic future thinking (constructing imagined futures)

NOTE: Alzeimer’s is both a type and cause of dementia.

Question 34

Causes or characteristics of Alzheimer’s

Answer 34

• Amyloid plaques
  
  • Protein (beta-amyloid) build up between neural synapses
• Neurofibrillary tangles
  
  • Protein build up within neurons; associated with cell death
• Imbalance in acetylcholine (NT)
  
  • Neurons that produce acetylcholine are destroyed
• Cortical shrinkage / brain atrophy
  
  • Progressive neuron damage causes brain tissue to shrink

Question 35

Aphantasia

Answer 35

• Inability to visualise due to function loss in visual cortex
  
  • Either congenital (present from birth) or acquired
• Those with aphantasia may…
  
  • Struggle to recall episodic memories
  • Struggle to imagine future or hypothetical events
  • Dream less and have trouble recognising faces
  • Have a reduced capacity to access other senses

Question 36

Mental imagery (FAQs)

Answer 36

• Perception-like experience in our conscious thought in the absence of external sensory stimuli

Question 37

Imagined futures

‘Episodic future thinking’

Answer 37

• Mentally experiencing an event that may occur in your personal future by projecting yourself forward in time
• Involves semantic and episodic autobiographical knowledge to create the ‘world’ in which the future thinking occurs

Question 38

How do autobiographical events and imagined futures influence each other? (FAQs)

Question 39

Mnemonic

Answer 39

• Any technique used to consciously assist memory
• Enhance encoding, storage and retrieval of info
• E.g. acronyms, acrostics, method of loci and songlines

Question 40

Mnemonics in written cultures

Answer 40

• Acronym – a pronounceable word formed from the first letters of a group of words (e.g. ANZAC, DRSABCD)
• Acrostic – phrase formed w words including the first letter of each item (e.g. never eat soggy weetbix = north east south west)
• Method of loci – converting items into mental images associated with specific locations

Question 41

How does the MOL improve encoding, storange and retrieval?

Answer 41

• Encoding – info is associated with familiar locations, making it more meaningful
• Storage – new info is linked to locations that are already kept in long-term memory
• Retrieval – visualising locations acts as a memory aid (allows the person to recall the associated w/ the spaces)

Question 42

Songlines

Used by oral cultures

Answer 42

• Multimodal performances (e.g. songs, dances, narratives) that form a journey, link sites and store knowledge that is passed down through generations
• Incorporates knowledge patterned on Country

Question 43

How do songlines enhance encoding?

Answer 43

• Link ideas together
• Facilitative elaborative rehearsal
• Link new ideas to known ideas

Question 44

Differences between songlines and method of loci

Answer 44

• Songlines
  
  • Information is sacred
  • Typically sung (rhymical and melodic)
  • Encoded through kinship networks
• Method of loci
  
  • Information is not tied to cultural learning
  • Typically not sung
  • Encoded individually for individual larning

Question 45

Differences between songlines and acrostics

Answer 45

• Songlines
  
  • Typically sung
  • Often increase in content over time
  • May contain content from a wide range of topics
• Acrostics
  
  • Typically not sung
  • Do not increase in content over time
  • Typically contain content relating to one topic
• Both
  
  • Act as retrieval cues
  • Rely on meaningful connections between words

Question 46

Similarities and differences between people with Alzheimer’s and aphantasia in being able to undergo episodic future thinking

Answer 46

• Similarity – both have difficulty with imagined futures
• Difference – cause of difficulty is different
  
  • Alz – increasing difficulty due to gradual degenaration of neurons (hippocampus, neocortex, cerebellum)
  • Aph – constant difficulty due to function loss in visual cortex

Question 47

Why are acrostics and acronyms more challenging to use when shared verbally rather than a written list?

Answer 47

• They require an understanding of the written spelling of a word
• W/o a visual cue of the first letter, the capacity of one’s STM is more likely to be exceeded
• It can make it harder to encode or retrieve the info