Memory

Question 1

Define memory

Answer 1

Process by which information is stored and retrieved, the ability to retain information over time
Memory is necessary for learning - Shettleworth 1998

Question 2

How long does short term memory (STM) store information? Long term memory? (LTM)

Answer 2

STM seconds->hours

LTM years

Question 3

How do studies of memory differ from studies of learning?

Answer 3

Learning- how relationships between events are learnt, which are learnt, how fast?
Memory- How information is encoded, stored and retrieved, what affects ease of this, how is information consolidated, mechanisms?

Question 4

Who studied Western Scrub jays?

Answer 4

Tarbell 2004 - food storing animals, appear to remember which trees food is hidden in. May be a rule - eg. go to smallest tree first etc.

Question 5

Neurally, what is short term memory doing?

Answer 5

Strengthening synaptic connections

Question 6

How does consolidation from STM->LTM occur?

Answer 6

Gene expression and protein synthesis - growth of NEW synaptic connections

Question 7

How may STM give behavioural outputs?

Answer 7

Behaviour alone or cued behaviour

Question 8

How may LTM give behavioural outputs?

Answer 8

Spontaneous behaviour (recall memory)
Cued behaviour (recognition memory)

Question 9

Which factors affect encoding to STM?

Answer 9

Duratino of exposure to stimulus, no. of discriminable features a stimulus has, interference from other stimuli, salience of stimuli (surprise/distinctiveness/motivational relevance/value/stress/emotional state)

Question 10

What must be considered when used delayed match to sample tasks to look at STM?

Answer 10

LTM is also used just to understand the task in the first place

Question 11

Give a study looking at duration of exposure to stimulus and STM encoding

Answer 11

Grant 1976 - pigeons delayed match to sample, extending time between first and second stimuli

Question 12

Give a study looking at no. discriminable features of a stimulus and encoding to STM

Answer 12

Zentall et al 1990 - pigeons adding colour to different shaped stimuli (delayed match to sample)

Question 13

Give a study looking at interference from other stimuli and encoding to STM

Answer 13

Whitlow 1975- Habituation in rabbits to a tone demonstrated.
Then, light flashed between two tones same distance apart, habituation ruined and same initial response occurs upon second play of tone - information has been overwritten following encoding (RETROACTIVE INTERFERENCE)
Then, light and tone played first, again when tone played alone second time same initial response occurs - information has been interfered with during the encoding process (PROACTIVE INTERFERENCE)

Question 14

What are primacy and recency effects?

Answer 14

Primacy - the first stimulus/picture/event is most memorable/ better recognition
Recency - the last stimulus/picture/event is most memorable/ better recognition

NB: Serial position curve of proactive and retroactive interference

Question 15

What phenomenon is displayed in the serial probe recognition task? In what species?

Answer 15

Pigeons, monkeys and humans. Different retention intervals (RI) -> different prevalence of primacy/recency effects
- Short RI = Recency effects, last stimulus best memorised
- Medium RI = U shaped
- Long RI = Primacy effects, first stimulus best memorised
NB: Exact RI depends on species (Long RI = pigeons 10s, monkey 30s, human 100s)

Question 16

Give two studies showing salience of stimulus affecting encoding to STM

Answer 16

Roberts 1980 - if matching to sample and all stimuli are circles, then one is a line, will be more easily matched
Laughlin and Mendl 2004 - pigs searching for food in 4 armed maze, when arms become costly to enter and search make fewer errors and remember better

Question 17

What is the effect of stimulus saliency on STM encoding known as in humans?

Answer 17

Von Restorff effect

Question 18

How does stress or emotional arousal impact encoding to STM?

Answer 18

Attention narrowing/focus - {task relevant }
Flashbulb memories - { stressors}
Attention shifts/lapses (task irrelevent stressors)
- Yerkes-Dodson Law

Question 19

Why is the salience of a stimulus able to impact its encoding?

Answer 19

The value or importance of the information attempting to be memorised

Question 20

What factors affect coding into LTM?

Answer 20

Cahill et al 1994 - Physiological responses to emotional stories increase memorisation. If given B blockers memory decreased

Question 21

What did Sandi and Rose 1994 do?

Answer 21

Chicks - food aversion with corticosterone/control injection. Corticosterone (HPA response) chicks showed markedly more avoidance
Also shown with adrenaline

Question 22

Which hormones are produced in response to an emotionally arousing or important stimulus? How do these act to affect memory?

Answer 22

Glucocorticoids and Catecholamines - GCs cross BBB -> Hippocampus directly, Catechols do not cross BBB but increase blood glucose enabling the brain to work more efficiently

Question 23

What did Cahill et al 1996 show?

Answer 23

Increased amygdala glucose associated with remembering more of an emotional film

Question 24

What are the two types of memory recall?

Answer 24

Recognition - cue similarity to stored information influences retrieval success. Context is important (external - location, odour, weather etc. Internal - affect, body clock etc.)
Recall - Apparently not cued, but possible that context and subconscious cues are registered

Question 25

What did Robinson and Rollings 2011 show?

Answer 25

Effect of neutral/emotional film on accuracy of recall and recognition

Question 26

At what stages may “forgetting” happen?

Answer 26

• Failure of encoding and temporary stooge in STM (limited capacity, interference effects, decay of STM trace, low salience/value ->v attention)
• Failure of consolidation into LTM (decay of STM trace, severe stress)
• Failure to retrieve information (inappropriate clues/context . decay of LTM)
• Active forgetting

Question 27

At what stage of encoding do early and late stage dementia affect?

Answer 27

Early - failure of encoding and temporary storage

Late - failure to retrieve information

Question 28

Outline a study regarding active forgetting

Answer 28

Maki and Hegvik 1980 Delayed match to sample in pigeons - learnt cue that meant forget and one that meant remember. If presented with task following forget cue did not perform well

Question 29

What did Karlsson and Frank 2009 investigate?

Answer 29

Spatial awareness memory in rats - hippocampal place cells fire in sequence as move around a maze. Replay during sleep indicating consolidation of memory.

Question 30

Outline a recall and recognition study in animals

Answer 30

Basile and hampton 2011 - Recall: touch space where rest of shape should be (recall of shape even in its absence)
Recognition: delayed match to sample, or if not correct press “wrong” logo
Results shown are similar to human recall and recognition therefore good indicator

Question 31

What are the two main forms of long term memory system?

Answer 31

Explicit (Concious, declarative) -> Episodic (personal events, and episodic future planning) and semantic (facts)
Implicit (Non-concious, procedural) -> Habits and skills, priming (where stimulus before test influences outcome, even if only subconsciously) simple classical conditioning

Question 32

How may episodic memory be demonstrated in animals?

Answer 32

Demonstrate that animals remember what happened, where and when -> episodic like memory

Question 33

Who argued that the human ability to travel mentally in time constitutes a discontinuity between us and other animals?

Answer 33

Suddendorf and Corballis 1997

Question 34

In which animals has episodic like memory been demonstrated?

Answer 34

Clayton and Dickinson 1998 - Florida scrub jays - cache food, prefer waxworks to peanuts, can be trained that worms decay after time. Show food, then let eat later, see which is preferred. Will choose peanuts if after time period where waxworms decayed
Raby et al 2007 - planning for breakfast in western scrub jays again - will cache a range of food to give themselves a choice in the morning

Question 35

How may study of memory impact animal welfare?

Answer 35

Pigs and rats remembering a familiar animal - memory acquisition and consolidation (length of time together, group size, rank)
Memory storage, interference and decay (duration of separation, interference stimuli, reminder cues)
Memory retrieval (social and contextual clues)
- recognition disrupted if introduced to new individual during separation and enhanced if subject is well acquainted with stimulus animal
(Burman and Mendl 2000, 2003, 2004)