Mazur Chapter 10: Comparative Cognition Flashcards
Short Term Memory or Working Memory
Short term memory is short lived and has a limited capacity.
The term working memory is used instead of short term memory
This reflects the view that info in working memory is used to guide whatever task the individual is currently performing.
Topic of study:
duration
capacity
factors that affect performance and accuracy.
Matching to sample task
Pigeons put in chamber; light in the center is either green or red (called the sample stimulus)
The pigeon needs to peck at this key to light up two side keys- (these two side keys are called the comparison stimuli) one will be red and the other green
Then the pigeon must peck at the matching color and will get food for right response.
Delayed matching to sample (DMTS)
There is a delay btw the sample key lighting up and the comparison keys lighting up.
By using different duration in the DMTS procedure, we can measure how long info is retained in working memory. This is different for different species.
Performance on DMTS can improve if the sample is presented for a longer duration
Other stimuli can interfere and affect performance
Retroactive Interference
Proactive interference
Retroactive interference
Occurs when the presentation of some new material interferes with the memory of something that was learned earlier
eg: learn list a & then b and then tested on list a
Proactive interference
Occurs when previously learned materials impair the learning of new material
eg; Memorizing list D after A,B, C, is harder than just memorizing list D
Conditional Discrimination Task
Similar to DMTS but more complex
The sample and comparison stimuli are not the same
e.g. the sample stimuli might be a green and red light but the comparison stimuli would be a horizontal black line and a vertical black line
task can be set up different ways, such as:
If red light is chosen, then choose horizontal line
If green light is chosen, choose vertical line.
Psychologist attempt to determine if animals use retrospective or prospective coding to retain information.
Retrospective coding
Looking backwards and remembering what happened
Prospective coding
Looking forward and remembering what response should be made next
Retrospective coding and Perspective coding with the rats in the Radial Arm Maze
Rats use visual landmarks to orient them within the maze to help them not repeat going to the arms they already visited.
Research on the rats patterns of errors suggest that during the first six trials, they used retrospective coding to remember which of the arms they visited, but then switch to prospective coding
This lessens the demands on working memory (when the rat only visited two arms, then it is easier to just think back and use retrospective coding instead of looking forward at the 6 other possibilities.
But if he has visited 5 arms, then looking forward is easier prospective coding bc there are 3 unvisited arms
Rehearsal
Overt or silent speech in which we repeatedly recite what we would like to remember
Maintenance Rehearsal –Helps to keep info in short-term memory
Associative Rehearsal –promotes the transfer of info into long-term memory and can help plan future actions.
Even in animals that do not use language, there is evidence for rehearsal
rehearsal in animals refers to an active processing of stimuli or events after they have occurred
can’t be observed directly only inferred from an animal’s behaviors on tasks
Maintenance Rehearsal
Process of rehearsal can be thought of as a covert behavior that an animal can learn to use or not use as the situation demands- it is an active process to maintain info in working memory
Directed forgetting
Directed Forgetting in humans
People are shown pictures or words and are told to remember some and forget others
They remember the ones they are told to remember more bc of rehearsal.
Directed Forgetting in Animals
conditional discrimination task:
there is a remember cue or a forget cue presented during the delay after the sample stimulus
The animal is trained that the remember cue means there will be a test coming up
Once the animal is trained, occasional probe trials are included in which the animal is tested after the forget cue
The animal does not do well on these trials, as they are not rehearsing on those trials
Associative Rehearsal
If people are given a list of items and then given a distraction free period, their ability to recall the material at a later time will be improved.
A study found that acquisition of a conditioned response proceeds more slowly if there is a post-trial episode (PTE) that distracts the animal.
Post Trial Episode (PTE)
Acquisition of a conditioned response proceeds more slowly if there is a post-trial episode (PTE) that distracts the animal
PTEs that are surprising are more distracting
Unexpected PTEs do not let the subject rehearse, which disrupted the development of a long-term CS-US association.
PTEs have the greatest disruptive effect when they closely follow each conditioning trial, keeping rehearsal to a minimum.
Rehearsal in Planning Behaviors
Humans and nonhuman animals both engage in mental rehearsal to plan behaviors before performing them
e.g. If a monkey moved the pendulum in the correct direction, it received their reward
Once a monkey learned the task well
- Its eyes moved toward the correct location before the objects moved
- Individual neurons in the premotor cortex started to fire before the monkey move the pendulum
*In a condition where the monkeys did not move their hands, their eye movements anticipated the movements of targets in the same individual neurons fired
**Neural firings reflected mental rehearsal – the monkeys were anticipating the correct movements even when they did not actually perform them
Long term memory (LTM), retrieval
One of the biggest distinctions btw short and long-term memory is their different storage capacity.
No one has really found a way to measure and quantify LTM for either animals or people.
Birds have a great memory for where they store food. Research has shown that birds use visual landmarks and spatial cues to remember.
Another study with Jays found that they don’t only remember where the food is but if the food is perishable or not. They will not search for perishable food if they needed to wait 4 days
Long-term memory, forgetting
forgetting is rapid at first, with a substantial loss during the first 24 hours
subsequent forgetting proceeds at a much slower rate
For humans there is a lot of interference from other stimuli and events in daily life
Both proactive and retroactive have been seen in animal studies
Context Shift Effect
Any stimulus that is present during a learning experience can later serve as a reminder and make it more likely that the experience will be remembered
If you learn something new in one context, your recall of the info will be better if you are tested in the same context than in a new context
If animals have forgotten something, it can be recovered if the animal is given the appropriate clue- evidence that it is retrieval failure
internal clock
Animals are fairly good at judging durations
Some psychologists have proposed that every animal has an internal clock that it can use to time the duration of events in its environment
This internal clock is said to include a pacemaker - much like a metronome, which pulses at a steady rate and allows the animal to measure durations.
In an experiment in which rats were reinforced every forty seconds, the rats were able to estimate the passage of time fairly accurately- they responded/pecked fastest at just about the time (40 seconds) a response might be reinforced
Peak Procedure
Used for studying animal timing abilities bc the peak of the response rate function tells us how accurately the animals could time the intervals
e.g. Rats and pigeons have shown that they can discriminate btw two stimuli if their duration differs by roughly 25% - so a rat can learn to press the left lever at time A and the right lever at time B.
Weber’s Law
The amount a stimulus must be changed before the change is detectable is proportional to the size of the stimulus.
An animal may be able to discriminate btw a 4 second tone and a five second tone (differ by 25%) but not btw a ten second tone and an 11 second tone (differ by 10%)
Behavioral Theory of Timing and the “Learning-to-Time Theory”
These theories state that animals can use their own behaviors to measure durations.
For example, the animal may walk to all four corners of an experimental chamber before making a response. There is an internal clock that sets the tempo but this internal clock is paced by the rate of reinforcers.
The rate of reinforcement controls the rate of the internal clock, which in turn controls the rate of the animals behaviors and the animal uses these behaviors to measure the passage of time
Counting
Procedures that require animals to count their own responses have shown that they can do so in an approximate way just as the peak procedures showed that animals could roughly time the absolute durations of stimuli
E.g. switching from lever A to lever B after 4 responses
Some research found that animals weren’t exact- they sometimes overestimated and sometimes underestimated
Other research found that it is possible that they can be exact at least with small numbers
Serial Pattern Learning
When learning response sequences, animals first need to learn the general rule (the overall structure repeating sequence) and only later do they learn exceptions to the rule
They use different cues to help them perform sequences correctly including spatial locations.
Chunking
Humans chunk pieces of info bc then it is easier to remember.
Animals can also use chunks of info as a strategy to remember a long list.
If a list is already organized into chunks, both animals and people can learn the list faster
If an already learned chunk reappears in a new list, the new list will be learned even faster
If a set of items is not already organized both animals and people may group similar items together and this will help to improve memory and avoid mistakes
Teaching language to animals
The chimp’s vocal apparatus does not permit him to make many human speech sounds
Using ASL, after learning how to sign in one context, the chimp used it in new contexts without training.
The chimp had great vocabulary but poor nonexistent grammar
Premack’s Attempts to Teach Language to Animals
Premack constructed a language consisting of different plastic shapes that represented different words. Sentences were created by placing the shapes on a magnetic board
The chimp learned to associate symbols with different objects and events but also learned that order of symbols were incredibly important
Premack taught the chimp the importance of word order by one-to-one substitution - he started with simple tasks and each new type of sentence would differ in only one way from the sentence forms the chimp already knew.
Limitations of Premack’s Study Methods
Chimps’ sentences were different than short sentences spoken by a typical 2-3 yr old.
There was no consistency of word order
There were pointless repetitions of signs and redundant signs
The average length of sign sequences leveled off at about 1.5 signs per sequences and did not increase - while children’s increase with age.
They don’t show spontaneous use of language
Evidence of Language Ability in Animals
Some of the main characteristics of human language have been found in animals are least at a rudimentary level:
Use of abstract concepts: words, signs, symbols
Productivity: ability to take a finite amount of words and make numerous combinations
Grammar: although limited some animals do have the capability to learn some basic principles of grammar
Displacement: ability to use language to talk about past or future and about object and event not currently present
some research says animals can do this while other don’t have evidence for this - this may be unique to humans
Communication: some research found that chimps do use language to communicate
Reasoning by Animals: Object permanence
animals follow more or less the same sequence of stages as human infants
eventually reach stage where they will correctly search for an object after an invisible displacement
Reasoning by Animals: Analogies
Tested a chimp that knew language on two different analogies: one that pertains to functional relationship and one can pertains to perceptual properties
Premack proposed that language skills are essential for analogical reasoning.
Reasoning by Animals: Transitive inference
Chimps were capable of making such inferences
Can be found in different species too.
Reasoning by Animals: Tool Use and Manufacture
Many different species know how to use tools
Animals also make their own tool
e.g. Chimps taught how to hit one stone against another to make a cutting tool
chimp first learned skills through observation, but others learn to make tools themselves
Reasoning by Animals: Metacognition
Thinking about ones thinking - ability to reflect on ones own memories and thought processes and make judgment about them
There has been some evidence that monkeys have some level of metacognition