Chapter 5: Memory

List 2 contributions to memory discovered by Ebbinghaus.

He invented nonsense syllables and carefully scored the number of recitations required to learn each list, or to relearn it after a decay had caused him to forget it.

He demonstrated that memory could be investigated scientifically as well as the fundamental contributions to study the learning process.

Describe the study of Ericsson and colleagues (1993) and what they found about the specific numbers of hours practiced

Ericsson and others emphasized the importance of practice across a number of skills, including chess, typing, and music. They suggested that the very best violinists have accumulated more than 10,000 hours of solitary practice compared to 7,500 for lesser experts, 5,000 for the least accomplished experts, and around 1,500 hours for the committed amateur.

Who later objected the Ericsson and colleagues (1993) study? What did they say?

In 2013, Ericsson objected to the 10,000 hour rule. Although the total time dedicated to an activity clearly improves a skill, more time is often not enough to ensure consistent learning; the simple repeated experience is not enough to develop true expertise.

What did Maguire and colleagues (200) find about the hippocampus in taxi drivers?

The found significantly larger hippocampi in a sample of London taxi drivers, who had been continually engaged in complex navigational problems for years. Due to the hippocampus being critical for spatial navigation, the extensive practice had presumably driven experience-related changes in that structure, ensuring superior performance.

Explain the study of Draganski and colleagues (2006) What did they find about study sessions?

They studies German medical students before, during, and after their three-month intensive preparation for an exam. Their findings showed that the students showed robust increases in cortical volume in the parietal cortex and the posterior hippocampus; these increases remained even three months after studying. It has been proposed that over time the brain renormalizes the volume in the regions enhanced by practice due to the limited space inside our skulls.

What was the main finding of Kornell & Bjork (2008) study that was surprising?

They were interested in the best way to teach people a general concept, a task that requires them to form a generalization from many examples aka induction. In their study they wanted to see if people would learn the style of an artist better by viewing many paintings by that artist in a row or by interleaving paintings by the artists in question with paintings by other artists.

Participants viewed 6 patients by each of 12 artists either in massed presentation (all 6 in a row) or distributed with other artists. On a later test, participants were presented with entirely new paintings by each of the artists and asked to pick the name of the artist that did each one from a list in front of them.

78% of participants said that the massed presentation led them to learn the styles better HOWEVER 78% of participants showed better performance in the spaced than the massed condition!!

Describe the postal worker study by Baddeley & Longman (1978). What did they do, find, and what does this tell us about memory?

The British Post Office developed a program that aimed to teach a large number of postal workers to type.

There were 4 feasible schedules in which postal workers were randomly assigned: two 2-hour sessions per day; 2 hour or two 1 hour sessions per day; or a single 1 hour session of typing per day.

Their findings showed that distributed practice is more efficient in terms of the benefit for the time invested, but it might not always be practical or convenient for the learner.

HOWEVER, using spacing to enhance your learning requires that you plan or study or practice efforts out well in advance, which is not always practical given the business of people’s schedules/lives.

What did Cepeda et al (2008) do and find?

They conducted a study entirely online by having people learn 32 obscure but true trivial facts. After learning these facts, participants logged on again to restudy these facts at delays ranging from 0 to 105 days. After the review, participants logged on for a final test either 5, 35, 70, or 350 days later to see how spacing affected recall at realistically long delays.

They found a sizable lag effect on final test scores that occurred regardless of how long they waited to test people.

Explain the study by Xue et al. (2010) and what they found

they had participants study either words or faces several times, while brain imaging data was collected. They found that items that were remembered on the final test always showed more similar brain activation patterns across their repetitions in the study phase than did items that were forgotten.

Their findings suggest that actively retrieving information may plan an especially important role in helping people to firmly learn something.

What did the study by Pyc & Rawson (2009) tell us about memory?

They had participants learn 70 Swahili-English word pairs by practicing the retrieval of the English word, given the Swahili cue. They manipulated both the time between successive retrievals (one minute or six minutes) and the number of retrievals (with feedback)

The more participants did retrieval practice, the better their later recall, indicating that multiple retrievals help a lot. The effect of lag between the initial study and the retrieval practice of the item showed that when separated by a mere minute, participants were nowhere near as good on the final test as when the tests were separated by six minutes.

This confirms the idea that harder retrievals are far more beneficial than easier retrievals.

What did Karpicke & Blunt (2011) do and find?

They asked students to study a science text under one of four conditions. To study the passage of text once, to repeatedly study the text over four consecutive study periods within the same session, the read the text and create a concept map with the text readily available to them, and finally to read the text and then have to recall it without any hints but then afterward getting to read the text again followed by a second recall attempt.

Their findings showed that retrieval practice not only promoted vastly superior memory for verbatim facts from the text, relative to both repeated study and concept mapping, but t also was superior in promoting meaningful inferences.

Retrieval tests enhance literal recall, but also promote learning that transfers to many situations in a generalizable way, justifying the phase retrieval-based learning.

What did Gruber et al (2014) study show us about how curiosity affects learning? What brain regions did they find to be activated in curiosity? What are the roles of these regions?

In the first phase of the study, participants reviewed a large body of trivia questions (without the answers) and were asked to rate (1) whether they knew the answer and (2) how curious they were to know the answer.

The found that when ppl felt very curious about a soon-to-be-received answer, it increased activity in the midbrain area called the ventral tegmental area (the VTA), and a second region in the ventral striatum known as the nucleus accumbens.

There was stronger communication between the VTA and the hippocampus, and this interaction predicted improved memory for answers and the faces on the delayed test.

The VTA promotes the release of a neurotransmitter called dopamine in the hippocampus, and in doing so, it enhances learning at the neural level.

What did Naveh-Benjamin & Brubaker (2019) find regarding dividing attention? How did they test for this?

Participants viewed 12 words, one at a time, with each word presented twice in spaced format, for 6 seconds. The experimenters told participants that they were interested in their physiological responses to the words, collected by electrodes that they had attached to them and to memorize the words for the later test. The incidental learning group was told nothing.

It didn’t matter whether people were intentionally memorizing the items – simply having another task tugging away attention dramatically limited their ability to register the words in memory.

What is the divided attention paradigm?

An experimental method used to measure how well people can perform two or more tasks at the same time.

What did Misra et al (2018) study tell us about the role of attention in memory?

They attached an eye tracker and a GoPro on participants and instructed them to walk along a fixed route in Boston. 24 hours later, they tested them on their memory for two-second video clips that could have been from their walk or another subject’s walk. On average participants only correctly recognized 55.7% of their own videos! This pattern held even when they examined what people’s eyes were focused on, which improved recognition only slightly.

This highlighted how little we actually retain of our daily lives!

How does dividing attention effect memory? What brain regions are affected by this and how?

Many studies have found that doing a second task during encoding significantly reduces activity in the prefrontal cortex, especially in the left ventrolateral prefrontal cortex.

An important role of the ventrolateral prefrontal cortex is to control memory encoding activity in the hippocampus. Thus, by facilitating activity in this region, the left prefrontal cortex enhances encoding and makes memories more durable.

By dividing attention, this function is undetermied, as reflected in its reduced activity. Partly bc of this, studies also find that when attention is divided, hippocampal activity no longer predicts whether you remember something.

Describe the study by Rosieli & Scaggs (2008)

They asked students to identify what was wrong with a picture of a familiar location on a college campus that students likely have visited hundreds of times. The change they made to the pictures were dramatic, for example, removing the library building from the scene. Although 97% of participants rates the scene as familiar, only 20% successfully detected the missing library!

What is change blindness?

The failure to detect that a visual object has moved, changed, or been replaced by another.

Describe the Stickgold and colleagues (2000) study on how sleep deprivation decreases learning retention

They asked people to learn a visual discrimination task. A group given normal sleep showed improvement increasing over several days following training whereas those deprived of a night’s sleep immediately after learning showed no such improvement.

Describe the Payne et al (2008) study on memory consolidation and images that are negative or neutral

They presented a series of negatively valenced objects against neutral backgrounds, testing after delays ranging from 30 minutes to 12 hours while awake, and after a 12-hour delay that included sleep. During waking, memory declined for both negative objects and their background at the same rate, whereas during sleep, less forgetting occurred for the negative objects. They suggest that such a pattern might be valuable from an evolutionary viewpoint.

Explain Graf & Mandler (1984) study

They visually presented a list of words, such as stamp, instructing subjects to process them either semantically, or in terms of their visual appearance.

Retention was then tested either by stem completion (i.e., an implicit memory task that gives participants the initial couple letters of the word and asking them to complete the stem with any valid word) or instead by asking them to consciously recall words, in response to an associated semantic cue (e.g., letter).

On the explicit memory task, there was a major advantage to semantic coding, HOWEVER no semantic advantage was found when performance was tested implicitly using the word fragment completion test. (a technique whereby memory for a word is tested by deleting alternate letters and asking participants to produce the word)

What were the main findings in Flegal & Anderson (2008)

They found that for golfers high in skill, attempts to describe their skilled behavior in detail after practicing it disrupts their later execution of the skill dramatically. Lower skill golfers were unaffected by this.

This suggests that proceduralized knowledge can be disrupted by attempts to put it into words.

What did Cavaco et al (2004) find about amnesic patients?

They found that amnesic patients could learn a complex multi-step motor skill involving a weaver’s loom at the same rate as control subjects and retain this skill 24 hours later, despite no memory or ever having done the task.

Describe the Bliss & Lomo (1973) study

They showed that after repeated stimulation, they found a persisting change in the ability of the stimulated neuron to influence activity in the receiving neuron, a process known as long-term potentiation (LTP).

The earlier repeated stimulation had enhanced the ability of the sending neuron to communicate with the receiving neuron, manifesting Hebb’s neurons that fire together wire together. They found that LTP arose prominently in the hippocampus and in surrounding regions, which is intimately concerned with LTM.

What is the total time spent hypothesis?

The proposal that the amount learned is a simple function of the time spent on the task (e.g., doubling time doubles information stored).

What is the deliberate practice framework?

It posits that expertise requires full concentration, immediate feedback, and exercises specifically designed to overcome weaknesses.

What are desirable difficulties? How do they affect memory processing?

Specific learning conditions that slow down immediate performance and feel harder in the moment, but result in superior long-term retention and knowledge transfer.

It affects memory processing by moving processing from superficial perception into elaborate semantic and structural encoding.

How does spacing create desirable difficulty?

By introducing a delay that lets minor forgetting happen, but when you return to the material the extra effort to reconstruct the memory reinforces the neural trace.

How does mixing create desirable difficulty?

Improves learning by forcing you to identify the specific underlying rules and differences between concepts rather than blindly applying the same formula repeatedly.

How does testing yourself create desired difficulty?

It forces active retrieval instead of passive recognition or rereading.

What is the deficient processing hypothesis?

It states that the spacing and lag effects both arise because people play less attention to recently encountered things and don’t process them as well as something that they saw longer ago

What is encoding variability?

Spacing allows for repetitions to be encoded in different ways or contexts, creating a richer array of retrieval cues.

What is the study-phase retrieval hypothesis?

Seeing a stimulus again triggers a retrieval of the first instance. The effort required for this retrieval strengthens the memory trace.

What is synaptic consolidation?

Refers to changes at the synaptic level wherein individual neurons involved in a memory undergo structural remodeling so that their interactions are altered in an enduring way by learning

Assumed to operate over a 24 hour timescale

What is systems consolidation?

Information initially represented by one part of the brain (e.g., the hippocampus) may be transferred to another part (e.g., neocortex), putatively ensuring its longer-term survival

Assumed to operate over a much longer period than synaptic consolidation.

What is sleep-dependent replay?

The observation that during sleep, material learning prior to sleep is often reactivated or replayed in the hippocampus, which is thought to facilitate the consolidation of that content into long-term memory.

What is sleep dependent triage?

The finding that sleep improves memory for content learned before sleep in a selective bay, favoring salient material (due to emotion or perceived importance) and facilitating the forgetting of less important material.

Describe Hebb (1949) study

He contrasts the long-term development of cell assemblies with a short-term process based on temporary electrical activity within existing cell assemblies.

Hebb’s proposal that long-term learning is based on the development and growth of further synaptic connections, known as Hebbian learning, is still influential in the field today

What are cell assemblies? Who was the psychologist that proposed the idea?

Cell assemblies are a concept proposed by Hebb to account for the physiological basis of long-term learning, which is assumed to involve the establishment of links between the cells forming the assembly.

These occur when two or more nerve cells are excited at the same time. This involves the synapse – the gap between two separate neurons – being repeatedly activated, whereupon the chemistry of the synapse changes, leading to a strengthened connection.

What is reward-based enhancement of memory encoding? What neurotransmitters are involved?

The tendency of rewards for successful memory to improve long-term retention of studied material.

This automatic reward-enhanced encoding effect appears to be driven by the same VTA-hipocampus interaction produced by curiosity and is believed to also reflect an increase in dopamine.

Just as with curiosity, the promise of reward also enhances memory for incidentally presented information while someone is awaiting the reward.

What is structural plasticity?

The brain’s capacity to alter its structure to adapt to environmental demands.

What is intrinsic plasticity?

The persistent change in a single neuron’s electrical excitability caused by its past activity.

Gray/White matter changes

Learning can increase the volume of neurons (gray matter) or enhance the efficiency of connecting pathways (white matter)

What is the spacing effect? What is the other name commonly used for this effect?

Improved learning when study attempts are separated by time rather than massed together.

Also known as the distributed practice effect.

What is the lag effect?

The improvement of learning/retention where there is greater time gap or physical separation between repeated study sessions.

What is the non-monotonic lag effect?

The tendency for the lag effect to first increase and to then decrease if it gets too long. Even when the lag was too long to be ideal, memory was always better than the 0-lag condition, so spacing always helped.

What is metamemory?

Knowledge about one’s own memory and the ability to regulate it.

Describe the fluency illusion

The mistaken belief that because material is easy to process now, it has been officially learned and stored long term.

What is the testing effect?

The phenomenon where LTM is enhanced more by retrieving information than by restudying it.

What is verbal overshadowing?

A phenomenon in which verbalizing difficult to articulate knowledge disrupts it.

What is extrinsic motivation? Give an example.

The drive to behave or perform a task in order to earn an external reward or avoid a negative consequence.

EX: getting a good grad on an exam

What is intrinsic motivation? Give an example.

The drive to do an activity for its own sake, fueled by personal joy, curiosity, or satisfaction rather than external rewards.

EX: taking part in your hobby

What is the value-directed remembering procedure? What does this tell us about how rewards influence memory encoding?

People intentionally memorize items for a later memory test, with each item being assigned a point value when it is presented and the goal to maximize point value is explicitly stated.

Evidence from this procedure illustrates that people often use deeper and more elaborate memorization strategies for high-value items.

What is intentional learning?

A conscious, deliberate cognitive process where acquiring specific knowledge or a skill is the primary goal rather than an incidental outcome.

What is incidental learning?

Unplanned or unintentional learning that happens naturally as a byproduct of another activity.

What type of memory is classical conditioning, priming, and procedural learning?

These are types of implicit memory (also known as non-declarative memory).

What is classical conditioning?

A profoundly general and important mechanism allowing us to associate stimuli in the world, and our own bodily responses, tuning exactly how our bodies work, based on experiences in the environment.

What is extinction?

The gradual weakening and eventual disappearance of a conditioned response when the conditioned stimulus is repeatedly presented without the unconditioned stimulus.

What is the pre-exposure effect?

Prior exposure to a stimulus before conditioning generally slows down or weakens how fast an organism learns an association.

What is backward conditioning?

A classical conditioning method where the unconditioned stimulus is presented before the neutral or conditioned stimulus.

What is latent inhibition?

A phenomenon where a familiar, neutral stimulus takes longer to become associated with a new meaning or consequence than a completely novel stimulus.

What is the amygdala?

An area of the brain close to the hippocampus that is involved in emotional processing.

What is the hippocampus?

A brain structure in the medial temporal lobe that is important for long-term memory function.

What is repetition priming?

Enhanced process of a stimulus arising from recent encounters with that stimulus, a form of implicit memory.

What is perceptual repetition priming? What does it rely on?

An increase in processing speed or accuracy based on the physical, sensory features or form of a stimulus.

It relies on the visual, auditory, or sensory match between the initial prime and the later target. It is highly sensitive to changes in modality (e.g., switching from a visual image to a spoken word often reduced the effect).

What is conceptual priming?

An increase in processing speed or accuracy based on the semantic meaning or category membership of a stimulus.

It relies on abstract associations, semantic networks, and general knowledge rather than physical form. It is not tied to a specific sensory modality of physical layout.

What is repetition suppression? What brain region(s) are involved in it?

Reduced activity in a brain area responsible for processing a stimulus when that stimulus is repeated, compared to when it is encountered for the first time.

It reflects the fact that the brain is more efficient at processing things it has already encountered. These effects are ubiquitously observed in every type of sensory cortex and are widely taken to reflect the formation of perceptual memory traces.

What is procedural learning?

Unconscious acquisition of skills, habits, and physical actions through repeated practice until they can be performed automatically without conscious thought.

What is skill learning?

A practice-induced change on a task that allows a person to perform it better, faster, and/or more accurately than before.

It can be divided into motor skill learning, which concerns learning physical skills, such as tying one’s shoes, skiiing, or typing, and cognitive skill learning, which concerns mental activities such as reading and mental calculations.

What is habit learning?

Gradually learning a tendency to perform certain actions, given a particular stimulus or context, based on a history of reward.

Habits can usually be considered examples of instrumental conditioning

A hallmark of habits is that they often persist when rewards for their outcomes are lessened or removed.

What is instrumental conditioning?

A response to a stimulus becomes more frequent upon being reinforced.

What is outcome devaluation?

A test of habit; occurs when a behavior persists even after the reward is removed.

What is automaticity?

When a skill is practiced to the extent that it no longer requires significant attentional monitoring to be performed and is less effortful.

What is performance plateau?

The point at which you reach an acceptable level of skill, turn on mental autopilot, and stop improving.

What did Ericsson argue about the performance plateau?

He argued that for many skill domains, performing a skill repeatedly will, after very high levels of practice, lead to a performance plateau, after which further practice yields little improvement even after many repetitions.

THUS, he proposed that the total time hypothesis must be qualified in that, after extensive practice, further repetitions benefit a person.

Only through deliberate practice can one break out of plateaus and continue to reap the benefits of further time.

Describe deliberate practice

The engagement (with full concentration) in a training activity that is designed to improve a particular aspect of performance, including immediate feedback, opportunities for gradual refinement over repetitions, and problem solving.

How can genetics influence the motivation to practice?

The tendency to practice itself is genetically heritable.

How are brain changes related to performance level?

Longitudinal studies have shown that robust increases in the brain areas relevant to tasks such as juggling, spatial navigation, and foreign language acquisition usually correlate with better performance.

How does forgetting help to strengthen relearning? What is this effect called?

The knowledge is far easier to relearn once again if it was initially required by spaced learning than by massing learning. This is an effect known as spacing accelerating relearning.

What did Astin (1993) report that the best predictor(s) of self-reported writing skill were?

He found that the best predictor of self-reported skill in writing was a number or writing skills classes taken, with the amount of feedback provided by the instructor being the second-best predictor.

What is consolidation?

The time-dependent process by which a new trace is gradually woven into the fabric of memory and by which it components and their interconnections are cemented together.

What are the main benefits of sleep for memory?

• When you get a good night’s sleep, it increases the changes that the hard work you put into learning something new will be consolidated in your brain and be woven into the fabric of memory.

• Taking naps from time to time during the day particularly if they can be arranged to occur right after you have learned something is beneficial.

What is long-term potentiation? What famous study was this observed in?

The persistent strengthening of connections between neurons based on recent patters of activity, serving as a primary cellular mechanism for learning and memory.

It has been most famously observed by using the Morris water maze

It is suggested that if the LTP is blocked (specifically in the rat), the capacity to induce LTP in the hippocampus is necessary for the rat to learn and remember where things are in its world.

What did the Morris water maze study tell us about hippocampal function?

It demonstrated that the hippocampus is essential for allocentric spatial memory – the ability to navigate and map out an environment using distal visual cues (landmarks outside the pool) rather than just moving directly to a visual object.