learning Flashcards
define learning and memory respectively
learning - change due to experience
memory - storage & reactivation of memories
Ebbinghaus in learning
- study of learning and memory
- only tested himself
- used nonsense syllables (consonant - vowel - consonant items)
- avoided associations with real words
- explored the rate of learning and forgetting
the total time hypothesis
the amount learned is a function of the time spent learning
experiment:
- lists of 16 syllables
- learned a new list each day - reciting the syllables at a constant rate
- 24 hours later he recorded how much m0ore the (number of trials) he needed to relearn the list
result: learning linearly related to amount of study - “practice makes perfect”
Psychology of “practice makes perfect” + structural change
- applies not only to word learning but also to skills e.g., writing, chess, typing, music
- the effect of extensive practice levels out (Ericsson, 2013)
- practice drives brain plasticity
- brain undergoes structural change in response to learning or environmental demands
- studies exploring structural changes in the brain due to expertise (long practice) or new learning
London Taxi Drivers study (Maguire et al., 2000)
- compared brain volume in taxi drivers relative to healthy controls
- the posterior hippocampus of the taxi drivers was consistently larger
- the size of the posterior hippocampus significantly correlated with the time they have spent as taxi drivers
New learning and brain plasticity - Draganski et al. (20060
Experiment:
- medical students scanned at three intervals
- before, during, and after intensive exams
result:
- increases in gray matter volume in the parietal cortex (A) and in the posterior hippocampus (B)
- remained even 3 months after studying
notes:
- changes assumed to be part of a process that optimises learning, but the structural changes are not perpetual
- over time, the brain renormalizes the volume in the regions enhanced by practice
- some structural changes (related to learning a task) may be selected and others dropped (expansions normalization hypothesis)
effect of repetition on memory
- simple repetition with no attempt to organize the material may not lead to learning
- especially if informaiton is complex and is not perceived as useful
- memory and attention are very selective - even after extensive practice/exposure informaiton is not registered if not deemed important
distributed practice
- distribute learning trials sparsely across a period of time
- faster improvement rates of learning and less forgetting
caveats:
- distributed practice takes longer - not always practical or convenient
- individuals may feel “less efficient”
distributed practice: experimental evidence (Melton, 1970)
experiment:
- list of words (one at a time), some presented once and some twice
- those presented twice appeared after variable lags (from 0 to 40 intervening words)
- varied presentation of each word (1.3s, 2.3s, 4.3s)
results:
- benefits to memory correlate with both presentation time and time lag
- lag effect = benefit of repeated study increases as the lag between study occasions increases
- overall: spaced learning of word stimuli increases subsequent recall
distributed practice, typing: Baddely and Longman (1978)
- rate of learning investigated using 4 different training schedules for typing
- found spaced learning as far more time efficient, achieveing a higher proficiency with fewer practice hours
distributed practice, spacing: Kornell and Bjork, 2008
- spaced presentation led to much better identification of new paintings by the same artist
- participants reported superiority of massed learning despite showing the opposite effect
deficient processing (explanation to distributed practice)
- less attention is paid to recently encountered stimuli
- after a longer delay stimuli attract more attention
encoding variability (explanation to distributed practice)
- multiple encoding instances create richer associations
- variety of ways stimulus has been encoded
study-phase retrieval (explanation to distributed practice)
- second presentation is a reminder of the previous occurrence
- this act strenghtens memory for the item
- bigger benefits when memory is not recent (more effortful)
distributed practice, neuroimaging evidence: Xue et al., 2010
Hypotheses:
- encoding variability: remembered items show different brain activity patterns across repetitions
- study phase retrieval: brain activation patterns are highly similar from repetition to repetition
Finding:
- the study-phase retrieval hypothesis is favoured by the data
- conclusion: similar brain patterns at study lead to better memory
The testing/generation effect study (Karpicke and Roediger, 2008)
Assigned 4 groups to learn Swahili-English word pairs over the course of a week
G1 - repeatedly studied and tested
G2 - after successful recall the word was not studied or tested more
G3 - After successful recall the word was not tested (studies continue)
G4 - after successful recall the word was not studied (tests continued)
Conclusion:
- G1 and G4 had a much higher retention rate after the week - the presence of tests is important
the testing effect
- shows that having to retrieve the answer, rather than being presented with, leads to greater retention
- testing promotes deeper learning
Feedback!
- errors in recall when training may affect later recall unless corrective feedback is provided
- the erroneous retrieval may be strengthened in memory
expanding retrieval method (Landauer & Bjork, 1978)
combines the following effects:
- spacing effect : spaced presentation enhances memory
- testing effect : successfully generating items strengthens memory
the sooner an item is tested after initial presentation, the more likely it will be recalled and strengthened
different types of motivated learning
- motivation to learn may make learning more efficient in both automatic and strategic ways
Automatic: external or internal motives prior to exposure to stimuli improves memory even when time spent studying or strategies used are controlled
Strategic: people use deeper and more elaborate memorization strategies for high value items
states have been shown to be associated with changes in a network of brain regions that critically involve the hippocampus
curiosity and learning
curiosity has a major effect of successful encoding - not just for the item triggeritg curiosity but for other incidentally presented stimuli (true of other internal motivations and external incentives too)
Gruber et al., 2014: curiosity during learning affects later memory
Hebbian learning (Hebb)
learning involves strengthening the connections of co-active neurons
- neutons repeatedly excited in synchrony
- the chemistry of the synapse between neurons changes
- each one becomes more likely to have action potential when the other does
- “neurons that fire together wire together”
other factors may contribute to learning e.g., intrinsic pasticity within neurons, making it easier to generate an action potential (Lisman et al., 2017)
Neurobiological evidence for Hebbian learning - Long term potentiation
- Bliss and Lomo (1973) stimulated axonal pathways led to lasting increases in the electrical potentials generated in post synaptic neurons = long-term potentiation
- LTP strongly represented. in the hippocampus and surrounding regions associated with long term memory
- also occue in the amygdala - supporting emotion-based learning and classicla conditioning
