Chapter 11: Memory Flashcards
comparative cognition
theoretical contructs and models used to explain aspects of behaviour that cannot be readily characterized in terms of simple S-R or reflex mechanisms
contemporary animal cognition
- test cognition w/ particular predicted behavioural outcomes
- animal cognition uses theory and models
- explain behaviour that cannot be explained through simple learning mechanisms
Potential lines of inquiry in contemporary animal cognition
how is info stored?
how is it retrieved and utilized?
how do animals navigate through the world?
how do animals judge time passing?
Memory
ability to respond on the basis of info that was acquired earlier
- inferred when current behaviour influenced by previous experience
Learning-memory distinctions
what is the diff. b/w learning and memory studies?
Focus is different during three stages of info processing
1. acquisition (encoding)
2. retention and interval (storage)
3. retrieval
working memory
ST, held long enough to complete the task at hand
reference memory
long term memories of background info needed to use incoming and recently acquired info
2 types
- procedural and declarative
2 types of reference memory
procedural and declarative
procedural memory
memory for well learned tasks
declarative memory
memory about the world
2 types
- semantic and episodic
semantic memory
store info necessary for functioning w/n our culture
episodic memory
memory for particular episodes
Working vs. reference memory
Hunter (1913)
subjects: rats, dogs and raccoons procedure: 1. light above box marked baited box 2. light turned off 3. animal detained in start box for variable amounts of time 4. then, after retention interval, allowed to choose box results: - longer delay, lower the accuracy -species differed: - rats max delay = 10 sec - racoons max delay = 25 sec - dogs max delay = > 5 min
Memory paradigms 1: delayed matching to sample (DMTS)
- peck centre key to start
- sample displayed on middle key
- early in training - sample remains on middle key
- late in training, samples no longer shown
then manipulate the delay between the sample and comparison
DMTS in honeybees, Gross et al (2009)
see slide
Factors affecting DMTS
- type of sample stimulus (some more effective than others)
- duration of sample (shorter the duration, the longer the accuracy)
- delay after sample before choice (longer the day, lower the accuracy)
classic DMTS experiment varying sample duration and delay (grant, 1976)
see slide
chnace performance = 50%
lomger sample duration + shorter delay = best performance
trace delay hypothesis of memory
Robert and Grant 1976
- stimulus presentation creates a change in the NS
- initial strength of trace related to the characteristics of the stimulus
- longer/more intense stimuli = stronger stimulus traces)
- these changes decay over time at the same rate
- forgetting functions reflect strength of memory
test of trace delay hypothesis (Sargasso and White, 2001)
Manipulated delay from the start of training
- 0 sec, 2 sec, 4 sec, 6 sec.
Tested memory for all groups w/ delays up to 10 sec
results:
- best w/ delays they were trained w/
Trace decay hypothesis Roberts and Grant (1976)
- stimulus presentation creates a change in the NS
- initial strength of trace related to the characteristics of the stimulus
- these changes decay over time at the same rate (NOT SO, the decay rate is related to similarity between conditions of testing and conditions of training).
- forgetting functions reflect strength of memory
general vs. specific rule learning in DMTS
animals may:
- focus on correct
- inhibit incorrect
- use both strategies
- in discrimination leanring procedures, animals use both (e.g. peak shift)
- in DMTS, the first option is used
- how do animals learn which is correct?
- matching (general) rule
- specific stimulus-response relationships
- depends on the size of the stimulus set:
- small set = specific rules
- large set = general rules (trial unique procedure)
