Chapter 5: Retrieval Processes (Part I)

Retrieval refers to the processes through which we recover items from memory (remembering?)

Note: Encoding and storage are necessary to acquire and retain information. But the crucial process in remembering is retrieval, without which we could not access our memories. Unless we retrieve an experience, we do not really remember it. In the broadest sense, retrieval refers to the use of stored information.

Encoding Specificity Principle (ESP)

The encoding specificity principle of memory (Tulving & Thomson, 1973) provides a general theoretical framework for understanding how contextual information affects memory. Specifically, the principle states that memory is improved when information available at encoding is also available at retrieval. For example, the encoding specificity principle would predict that recall for information would be better if subjects were tested in the same room they had studied in versus having studied in one room and tested in a different room (see S.M. Smith, Glenberg, & Bjork, 1978).

When you store something in memory, the memory is not just of the item being organized and stored but also of the context in which the memory occurred. Recall and recognition thus may be triggered by elements of the context being present.

Remembering knowledge is enhanced when conditions at retrieval match those present at encoding. When retrieval cues differ substantially from those present at encoding, an efficient search of memory may be impossible! (Create a richer context for retrieval – Cuing in widest possible range of context/situation – maximum remembering!)

So what?

To get people to remember something, make use of the context in which it happened.

Context Effects

A person’s memory will be best if the testing occurs in same context as the learning.

Environmental Context Effect — refers to anything external in the environment

•   If given a list to learn in one room, will do better on a memory test if in the same room at test

State-dependent Effects — refers to drug states

•   If in a drug state at learning, you will remember better at test if under same drug than if sober

•   Note: you will do best if sober both times

Mood-dependent Effects — refers to mood state

•   If in a particular mood while learning, will do better at test if in the same mood.

There ought to be a link between encoding & retrieval — perhaps good memory is a result of a good link. What leads to good memory? — Memory cues — cues lead to retrieval (e.g., face – name)

Q: So, what makes a retrieval cue effective?

A retrieval cue is any stimulus that helps us recall information in long-term memory. The fact that retrieval cues can provoke powerful recollections has led some researchers to speculate that perhaps all memories are permanent. That is, perhaps nearly all experiences are recorded in memory for a lifetime, and all forgetting is due not to the actual loss of memories but to our inability to retrieve them. This idea is an interesting one, but most memory researchers believe it is probably wrong.

Two general principles govern the effectiveness of retrieval cues. One is called the encoding specificity principle. According to this principle, stimuli may act as retrieval cues for an experience if they were encoded with the experience. Pictures, words, sounds, or smells will cause us to remember an experience to the extent that they are similar to the features of the experience that we encoded into memory. For example, the smell of cotton candy may trigger your memory of a specific amusement park because you smelled cotton candy there.

Distinctiveness is another principle that determines the effectiveness of retrieval cues. Suppose a group of people is instructed to study a list of 100 items. Ninety-nine are words, but one item in the middle of the list is a picture of an elephant. If people were given the retrieval cue “Which item was the picture?” almost everyone would remember the elephant. However, suppose another group of people was given a different 100-item list in which the elephant picture appeared in the same position, but all the other items were also pictures of other objects and animals. Now the retrieval cue would not enable people to recall the picture of the elephant because the cue is no longer distinctive. Distinctive cues specify one or a few items of information.

Overt cues such as sights and sounds can clearly induce remembering. But evidence indicates that more subtle cues, such as moods and physiological states, can also influence our ability to recall events.

State-dependent memory refers to the phenomenon in which people can retrieve information better if they are in the same physiological state as when they learned the information. The initial observations that aroused interest in state-dependent memory came from therapists working with alcoholic patients. When sober, patients often could not remember some act they performed when intoxicated. For example, they might put away a paycheck while intoxicated and then forget where they put it. This memory failure is not surprising, because alcohol and other depressant drugs (such as marijuana, sedatives, and even antihistamines) are known to impair learning and memory. However, in the case of the alcoholics, if they got drunk again after a period of abstinence, they sometimes recovered the memory of where the paycheck was. This observation suggested that perhaps drug-induced states function as a retrieval cue.

A number of studies have confirmed this hypothesis. In one typical experiment, volunteers drank an alcoholic or nonalcoholic beverage before studying a list of words. A day later, the same subjects were asked to recall as many of the words as they could, either in the same state as they were in during the learning phase (intoxicated or sober) or in a different state. Not surprisingly, individuals intoxicated during learning but sober during the test did worse at recall than those sober during both phases. In addition, people who studied material sober and then were tested while intoxicated did worse than those sober for both phases. The most interesting finding, however, was that people intoxicated during both the learning and test phase did much better at recall than those who were intoxicated only during learning, showing the effect of state-dependent memory.

When people are in the same state during study and testing, their recall is better than those tested in a different state. However, one should not conclude that alcohol improves memory. As noted, alcohol and other depressant drugs usually impair memory and most other cognitive processes. Those who had alcohol during both phases remembered less than those who were sober during both phases.

Psychologists have also studied the topic of mood-dependent memory. If people are in a sad mood when exposed to information, will they remember it better later if they are in a sad mood when they try to retrieve it? Although experiments testing this idea have produced mixed results, most find evidence for mood-dependent memory.

Mood- and state-dependent memory effects are further examples of the encoding specificity principle. If mood or drug state is encoded as part of the learning experience, then providing this cue during retrieval enhances performance.

Sampling

Click on the link below…

Sampling.ppt

1. Simple Random Sampling

Individuals are chosen in such a way that each has an equal chance of being selected, and each choice is independent of any other choice. If we wished to draw a sample of 50 individuals from a population of 600 students enrolled in a school, we could place the 600 names in a container, and, blindfolded, draw one name at a time until the sample of 50 was selected. However, this process is cumbersome (burdensome) and is rarely used. A more convenient way of selecting a random sample, so that the individuals can be equated, is by the use of a “table of random numbers.” When a table is used, it is necessary to assign consecutive numbers to each member of the population (from which the sample is to be selected). Then, entering the table at any page, row, or column, the researcher can select the sample from 001 to 999 (three digits); and from 0001 to 9999 (four digits). When a duplicated number or a number larger than the population size is encountered, it is skipped and the process continues until the desired sample size is selected.

*Ask me to demonstrate when you are in your expert group…!!!

2. Systematic Sampling

Consists of the selection of each nth term from a list. For example, if a sample of 200 were to be selected from a telephone directory with 200,000 listings, one would select the first name by selecting a randomly selected name from a randomly selected page. Then every thousandth name would be selected (200,000/200=1000th) until the sample of 200 names was complete. If the last page were reached before the desired sample size had been selected, the count would continue from the first page of the directory. Systematic sampling, sometimes called interval sampling, means that there is a gap, or interval, between each selection. This method is often used in industry, where an item is selected for testing from a production line (say, every fifteen minutes) to ensure that machines and equipment are working to specification. Alternatively, the manufacturer might decide to select every 20th item on a production line to test for defects and quality. This technique requires the first item to be selected at random as a starting point for testing and, thereafter, every 20th item is chosen. This technique could also be used when questioning people in a sample survey. A market researcher might select every 10th person who enters a particular store, after selecting a person at random as a starting point; or interview occupants of every 5th house in a street, after selecting a house at random as a starting point. It may be that a researcher wants to select a fixed size sample. In this case, it is first necessary to know the whole population size from which the sample is being selected. The appropriate sampling interval, I, is then calculated by dividing population size, N, by required sample size, n, as follows: I = N/n

3. Stratified Random Sampling

This is possible when the population is subdivided into smaller homogeneous groups, called strata (to get more accurate representation). For example, in an income study of wage earners in a community, a true sample would approximate the same relative number from each socioeconomic level of the whole community. If, in the community the proportion were 15% professional workers, 10% managers, 20% skilled workers, and 55% unskilled workers, the sample should include approximately the same proportions in order to be considered representative. Within each subgroup, a random selection should be used. Thus, for a sample of 100, the researcher would randomly select 15 professional workers from the subpopulation of all professional workers in the community, 10 managers from that subpopulation, and so on. This process gives the researcher a more representative sample than one selected from the entire community, which might be disproportionately weighted by a predominance of unskilled workers. In addition to socioeconomic status, such characteristics as age, sex, extent of formal education, racial origin, religious or political affiliation, or rural-urban residence might provide a basis for choosing a stratified sample (strata).

4. Area or Cluster Sampling

It is sometimes expensive to spread your sample across the population as a whole. For example, travel can become expensive if you are using interviewers to travel between people spread all over the country. To reduce costs you may choose a cluster sampling technique. This sampling technique is appropriate when, a) the population of interest is infinite, b) when a list of members of the population does not exist, or, c) when the geographic distribution of the individuals is widely scattered. Let’s say we want to select a sample of all public school elementary teachers in the five largest cities in Thailand (Bangkok, Nakhon Ratchasima, Nonthaburi, Chiang Mai, and Songkhla). A simple random sample would be impractical. From the 5 largest cities, three could be selected. From these three cities, all public elementary schools could be listed and a random sample of 30 (10 from each city) can be selected. From these 30 schools, we can then randomly select 5 teachers in each school. So, our true sample will be – 30 x 5 = 150 elementary school teachers.

Non-probability Sampling

Those that use whatever subjects are available, rather than following a specific subject selection process

May produce samples that do not accurately reflect the characteristics of a population

May lead to unjustifiable generalization and should not be used if random selection is practicable

Educational researchers, because of administrative limitations in randomly selecting and assigning individuals for a research, often use available classes as samples (e.g.: psychology professor uses students from Introduction to Psychology class as subjects – the results of this study can be generalized only to other similar groups of psychology students)

So, this kind of sampling may restrict generalizations (generalizable only to similar population)

Sample made up of volunteers may represent biased sample – volunteers may not necessarily be representative of a total population

1. Convenience sampling – selection based on the availability of subjects (whomever happens to be available at the time); also known as accidental sampling or haphazard sampling; sampling bias can occur

Volunteers

Pre-existing groups

2. Purposive sampling – selection based on the researcher’s experience and knowledge of the group being sampled; also known as judgment sampling; researcher believes a particular sample is appropriate for his/her study

Need for clear criteria for describing and defending the sample

Experience and prior knowledge of the researcher about a particular group (to be used as sample) are essential

The researcher can be “wrong”

3. Quota sampling – selection based on the exact characteristics and quotas of subjects in the sample when it is impossible to list all members of the population (e.g.: an interviewer might be told to go out and select 20 adult men and 20 adult women, 10 teenage girls and 10 teenage boys so that they could interview them about their television viewing)

Data gatherers are given exact characteristics and quotas of persons to be interviewed (e.g.: 35 working women with children under the age of 16, 20 working women with no children under the age of 16, etc.)

Data are obtained from easily accessible individuals

Thus, people who are less accessible (more difficult to contact, more reluctant to participate, and so forth) are underrepresented

Qualititative Sampling

Because of the unique characteristics of qualitative research, both random and non-random sampling techniques cannot be used. This calls for alternative sampling strategies for qualitative research.

In-depth inquiry

Immersion in the setting

Importance of context

Appreciation of participant’s perspectives

Description of a single setting

A qualitative researcher relies on his/her experience and insight to select participants. There are several types of sampling techniques possible for a qualitative study:

1. Intensity sampling = compare differences of two or more levels (“extremes”) of the research topic; e.g.: good vs. poor students (two extremes); effective vs. ineffective teachers (two extremes); small vs. medium vs. large size classes (three extremes), experienced vs. inexperienced teachers, etc.

2. Homogeneous Sampling = Subjects chosen by similarity based on a given characteristic

3. Criterion Sampling = Selection of all cases that meet a certain standard

4. Snowball Sampling = Selection of subjects who identify other subjects; one subject gives the researcher the name of another subject, who in turn provides the name of a third, and so on (e.g.: drug dealers, criminals, gay, isolated, etc.)

5. Random Purposive Sampling = From a purposive sample too large for a study, a random selection is performed

Sample Size?

Time

Money

Access

Complexity of data analysis

Chapter 4: Encoding (Part II)

Two kinds of learning:

  1. Simple – involves associating terms and acquiring them through rehearsal (e.g. memorizing grocery list, name of capital cities, etc.)

  1. Complex – involves understanding, reasoning, and critical thinking (e.g. digestive processes, chemical reactions, etc.)

Two types of Rehearsal:

  1. Maintenance rehearsal – shallow encoding; direct recycling of information in order to keep it active in STM (verbal repetition); retention is limited in this kind of encoding; highly efficient for a short-while; e.g. taking down someone’s telephone number; seldom last long L

  1. Elaborative rehearsal – information to-be-remembered is related to other information; deeper or more elaborate encoding activity; leads to high level of recall; sometimes, information can be broken into component parts and related to what one already knows

Strategies for encoding complex information:

Schema activation

Instructional techniques designed to bring to mind students’ relevant knowledge prior to their encountering new information

New knowledge is built on prior knowledge (bridging what they already know and what they want to know)

KWL method

Guided Questioning

Asking and answering questions about a text or teacher-presented information can greatly improve comprehension (hence, improve memorization and learning)

Allows students to think about, discuss, compare and contrast, infer, evaluate, explain, justify, synthesize, etc.

Guided peer questioning

Levels of Processing

What learners DO as they encode new information matters a great deal!

Memory/learning depends on depth of processing

1. Deep processing = processing centered on meaning (e.g. read ‘something’ and talk to the class about it without referring to any material, in one’s own words, etc.)

2. Shallow processing = keying on superficial aspects of new material (e.g. underline new words in the book, and look up for their meaning)

Chapter 4: Encoding Processes (Part I)

Encoding affects retention (storage) and retrieval of information from memory

Two kinds of learning:

  1. Simple – involves associating terms and acquiring them through rehearsal (e.g. memorizing grocery list, name of capital cities, etc.)
  2. Complex – involves understanding, reasoning, and critical thinking (e.g. digestive processes, chemical reactions, etc.)

*according to research in cognitive psychology, encoding is enhanced when we combine and thoughtfully use strategies to learn simple information (imagery, linking, mnemonics, etc.) with strategies to learn complex information (understanding, reasoning, problem-solving, attaching meaning, etc.)!

Encoding Simple Information

Two types of Rehearsal:

  1. Maintenance rehearsal – shallow encoding; direct recycling of information in order to keep it active in STM (verbal repetition); retention is limited in this kind of encoding; highly efficient for a short-while; e.g. taking down someone’s telephone number; seldom last long L
  2. Elaborative rehearsal – information to-be-remembered is related to other information; deeper or more elaborate encoding activity; leads to high level of recall; sometimes, information can be broken into component parts and related to what one already knows

* Different types of rehearsal are appropriate for different type of tasks

Q: Give examples of the type of tasks (in your own life) that would require you to use

Maintenance rehearsal strategies

Elaborative rehearsal strategies

Strategies

Mediation – tying difficult-to-be-remember items to something more meaningful; results in deeper, more elaborate encoding than simple repetition of new content

Imagery – encoding using images/pictures (non-verbal); leads to better memory performance; easily imagined words (more concrete in nature, like ‘car’, ‘pencil’, etc.) tend to be remembered more readily than hard-to-imagine words (more abstract in nature, like ‘freedom’, ‘truth’, etc.); this activity can be extended to encode complex CONCEPTS too; consider individual differences among students in tier ability to image information; some students are better able to employ imagery than others and these differences seem to lead to differences in memory performance; best images (that enhance memory) are bizarre (vs. mundane), colorful, and strange.
Mnemonics:

The Peg Method – students memorize a series of ‘pegs’ on which to-be-learned information can be ‘hug’ one item at a time; e.g.

One for bun

Two for shoe

Three for tree

Four for door

Five for hive

Six for sticks

Seven for heaven

Eight for gate

Nine for pine

Ten for hen

Construct a visual image of the first thing on the to-be-learned list interacting with the object named in the first line of the rhyme

The Method of Loci – mentally walking through a ‘location’ (that one is extremely familiar with); each item (sofa, table, window, television, etc.) in the ‘location’ is linked to particular to-be-learned information

The Link Method – no need for a previously learned set of materials like the rhyme or ‘location’; used when learning list of things; student forms an image for each item in a list of things to be learned; each image is pictured as INTERACTIING with the next item on the list; all of the items are linked in imagination

Stories – stories can be constructed from a list of words to be remembered, the to-be-learned words in a list are put together in a story such that the to-be-learned words are highlighted; at recall, the story is remembered and the to-be-remembered words are plucked from the story

The First-Letter Method – using the first letters of to-be-learned words to construct acronyms or words

The Keyword Method – to facilitate vocabulary acquisition; used in connection with imagery; two stages (illustrated with an example of learning the word, ‘captivate’)

  1. Acoustic link – search for a ‘keyword’ within the to-be-learned word, let’s say ‘cap’
  2. Imagery link – link this keyword, ‘cap’ with an image (image from real-life connected to one’s experiences)

Copyright September 2006 by Dr. Edward Roy Krishnan, www.affectiveteaching.com

Chapter 3: Long-Term Memory

Sensory Memory & Short-Term Memory

Long-Term Memory

Recent experiences

Memory traces developed over periods of days, weeks, months, & years

Things that are currently in consciousness

Lifetime of information

Rehearsal / repetition are crucial

Meaning & organization are crucial

Capacity & retention duration are limited

Permanent repository (storehouse)

Recall = understanding information + retrieving LTM becomes particularly important if we believe that learning is a constructive process (creation & re-creation of new knowledge in the context of previously established and retrievable knowledge) – role of prior knowledge and experience – it’s like building a new house using whatever resources you already have (bricks, cement, tiles, planks, etc.).

Types of Knowledge:

  1. Declarative Knowledge = factual knowledge (knowing ‘what’)

Semantic Knowledge = general knowledge – concepts and principles – meaning and understanding of meaning

Episodic Knowledge = personal experiences – personally dated, autobiographical experiences – “personal tags” association recall

  1. Procedural Knowledge = process knowledge (knowing ‘how’)
  2. Conditional Knowledge = knowing ‘when’ and ‘why’ to use DK & PK (needed to help us use DK & PK in real-life settings – at the right time, in the right place, for the right purpose)

Explicit Memory

Implicit Memory

Involves conscious recall or recognition of previous experiences; intentional information retrieval; a conscious or voluntary search for information

declarative memory

Knowing information about a bike

Knowledge without awareness; unintentional, non-conscious/unconscious form of retention; actions influenced by a previous event but without conscious awareness/remembering; e.g., using computers, tying shoes, driving a car (procedural knowledge, conditioning, habituation); behavior can be influenced by memory of past events even without conscious awareness (stereotypes & prejudice?)

In fact, when a person tries to reflect on how these skills are being performed, performance often deteriorates

Non-declarative memory

Knowing the physical process of riding a bike

Note:

We may know how to ride a bike, but it is very difficult to explain how to do so.

If we believe in implicit memory or learning, it seems that people are unconsciously acquiring rules that they can use but NOT articulate.

Overall, we are good at getting ‘the gist’ of things but falter on details!

The Building Blocks of Cognition (What make cognition possible?)

  1. Concepts
  2. Propositions
  3. Schemata
  4. Productions
  5. Scripts

Note:

1, 2, & 3 = ways of representing declarative knowledge

4 & 5 = ways of representing procedural knowledge

Concepts

Conceptual categories – everything we know can be placed under meaningful categories based on perceived similarities (examples vs. non-examples of a concept)

Attributes = similarities or common features required to define a concept

Defining attributes = features essential to defining a concept

Learning a concept involves discovering the defining attributes and discovering the rule or rules that relate the attributes to one another – leads to the formation of hypotheses and the testing of the same by examining attributes and rules

Role of culture? Categorizing abstract concepts?

Propositions

Consist of concepts

The mental equivalent of statements or assertions (claims) about observed experiences and about the relationships among concepts

Can be judged to be true or false

Meanings emphasized rather than the exact form of information

We retain meaning and not the surface structure of information (these are quickly lost)

Propositions do not stand alone – connected with one another and may be embedded within one another

A complex proposition is usually broken into simpler sentences (‘idea unit’) to enhance understanding of the meaning presented by the proposition

Propositional networks = propositions sharing one or more elements are linked with one another (our ability to comprehend information and to use if effectively in cognitive operations such as problem-solving depends on the quality of networks we are able to create

Schemata

Mental frameworks that we use to organize knowledge

Control the encoding, storage, and retrieval of information

Data structures that represent knowledge stored in memory

Fundamental to information processing

Represent our knowledge about objects, events, sequences of events, actions, and sequences of actions

When a fresh knowledge is acquired via accommodation (adding) or assimilation (changing and fitting into existing schemata), a new schema is said to be created

Once a new schema is created, its traces serve as a basis of our re-collection – it is part of our long-term memory repository

When schemata are not or cannot be activated during learning, new knowledge cannot be assimilated easily

Memory consists of representations of knowledge, rather than exact copies of it…thus, encoding will vary according to the schemata activated at the time of encoding (learning). In this sense, recall is not simply remembering/recalling stored information…rather, it is re-creating information and events – memory is constructive and re-constructive in nature!

Productions (can be compared to propositions)

‘Condition-action’ rules – actions occur if the specified condition(s) exist

If…then rules

Memory for productions = implicit memory (conscious thought not involved)

Automated skills

Productions are organized in networks called ‘production systems’ – multiple productions may be active at a given time

Example:

Production A: If car is locked, then insert key in lock

Production B: If key is inserted in lock, then turn key

Production C: If door unlocks, then return the key to vertical

Production D: If key is vertical, then withdraw key

Scripts (can be compared to schemata)

Provide underlying mental frameworks for our procedural knowledge

Schema representation for events

Contain action sequences and subsequences + actors + objects + characteristics of the setting

Accountable for stereotypical patterns of activity

Copyright September 2006 by Dr. Edward Roy Krishnan, www.affectiveteaching.com

Chapter 2: Sensory, Short-Term/Working, and Long-Term Memory

“Minds are like parachutes – they only function when open”
– Thomas Dewar

Memory (psychology) – processes by which people and other organisms encode, store, and retrieve information. Encoding refers to the initial perception and registration of information. Storage is the retention of encoded information over time. Retrieval refers to the processes involved in using stored information. Whenever people successfully recall a prior experience, they must have encoded, stored, and retrieved information about the experience. Conversely, memory failure-for example, forgetting an important fact-reflects a breakdown in one of these stages of memory.

Memory is critical to humans and all other living organisms. Practically all of our daily activities-talking, understanding, reading, socializing-depend on our having learned and stored information about our environments. Memory allows us to retrieve events from the distant past or from moments ago. It enables us to learn new skills and to form habits. Without the ability to access past experiences or information, we would be unable to comprehend language, recognize our friends and family members, find our way home, or even tie a shoe. Life would be a series of disconnected experiences, each one new and unfamiliar. Without any sort of memory, humans would quickly perish.

Without memory we would be wanderers in a world that was perpetually new and unfamiliar. There are two methods psychologists use to study memory. The first is through self-reporting (introspection), and this approach involves asking participants to record the way they remember and forget. The second method is naturalistic study, and is often experimental in nature. Naturalistic experiments attempt to reproduce events that are more representative of real life, and participants are often asked to remember natural material such as stories, films, events, maps or other visualised material, instead of lists of letters, nonsense syllables or digits

Click on the Link Below:

The Modal Model of Memory1.ppt

The basic characteristics of the model include:

  1. the existence of several linked processing systems;
  2. stage-by-stage processing of information;
  3. a unidirectional flow of information.

The modal model, or multistore model, of memory has become one of the most well-known theoretical memory models. The creators of this approach hypothesize that all parts of the memory system can be divided into two main categories: the control processes and the permanent structure. The control processes are the procedures that one performs in order to encode, maintain, and retrieve memories. The permanent structure includes the different memory stores, which are described in detail below.

The Sensory Store

The sensory store, or the register, records information that comes in through the senses. The information only remains in this store for a few seconds after the stimulus is gone.

The two senses that have been studied the most in terms of their role in memory are vision and hearing. The term “iconic memory” refers to visual impressions in the sensory store. Auditory information that enters the sensory store is called “echoic memory”. One’s iconic memory might hold, for instance, the visual impression of a firework, while the echoic memory will hold for a few seconds the loud noise of the firework.

Most of the information in the sensory store vanishes forever after a few seconds. If all of these information were kept and focused on, we would be so bombarded with stimuli that we would be unable to function. Instead, the brain is constantly going through a selection process to decide which sensory memories are necessary to keep and which should be thrown away. The information that is kept and processed passes into the short-term memory store.

  • visual sensory is very limited. Only seven to nine pieces of information are processed at any given time, and much of that decays rapidly. Information held in visual sensory memory receives only limited processing (less than 0.5 second for iconic register and recall)
  • auditory register and recall (echo) – slightly more than 3 seconds – ability of the echo to retain information seems related to the processing of language
  • Knowledge and context play important role in our perceptual processes – previous knowledge and past experiences!
  • attention = a person’s allocation of cognitive resources to the task at hand
  • attention is maximized if one engages in resource-limited tasks (focusing on one task at a time – e.g. watching television while reading?) and avoid data-limited tasks (tasks that you do not possess much knowledge and skills about) – e.g. learning advanced math without having proper foundation in basic math
  • the role of automatic processes (vs. controlled processes) – require fewer cognitive resources than nonautomated processes

Q: Will being exposed to stimuli from various modality (visual, auditory, gustatory, tactile/haptic, olfactory, etc.) help to enhance memorization of a particular experience? Why do you say so? – enhancement in exposure!

Sensory memory briefly processes a limited amount of incoming stimuli. Visual registers hold about 7 to 9 pieces of information for about 0.5 second. Auditory registers hold about 5 to 7 pieces of information for up to 4 seconds. Incoming stimuli are perceived, then matched to a recognizable pattern, and then assigned a meaning. How much information we can process depends on two things: 1)the complexity of the information and 2)our available resources. Automated tasks are easy to perform because they require fewer attentional resources. Resource-limited tasks are difficult no matter how much attention we allocate because the information itself is deficient.


Short-Term Memory (7 plus/minus 2) –
the size of the chunks doesn’t really matter!

The short-term memory store holds memories for about thirty seconds. Much of this memory is then forgotten. However, the more important information is then transferred into the long-term memory store. The brain engages in this process naturally, but we can also to an extent control this process by rehearsing, or repeating new memory in order to encode it.

Short-term memory is often referred to as “working memory”. This is because the short-term memory store does not only hold memories, but it also manipulates information and uses it to perform tasks. Working memory consists of three parts. The first component involves perceived sounds, and the second is concerned with visual and spatial information. The third part, the “central executive”, uses information from the first two parts as well as from the long-term memory store.

Like sensory memory, the capacity and duration of short-term memory are quite limited. We hold approximately 7 (plus/minus 2) pieces of information in working memory at a time. This information is forgotten quickly because of interference, decay, and replacement by new information.

The working memory includes a central executive, articulatory loop, and visual-spatial sketch pad. The central executive coordinates the two remaining slave systems, which are responsible for maintenance of verbal and spatial information. Research suggests that each subsystem possesses some unique resources that enable individuals to distribute information processing load.

How do we access information in the STM?

people search the contents of short-term memory in a serial (search one by one) and exhaustive (detailed and meticulous – going through all the items) fashion NOT parallel or search all item in memory simulataneously and self-terminating or ending search when one finds something he/she is looking for

Long-Term Memory

The long-term memory store contains nearly all of what we consider our memory. There are several ways to code memory into this store, some more effective than others. One technique used to improve encoding is elaboration, the connecting of new information to information already in the long-term store. Elaboration may be conscious, such as when mnemonic devices are used, or it may be unconscious.

Note: It is possible for information to enter long-term memory (LTM) without ever entering short-term memory (STM). Researchers have found that individuals with severe STM damage still somehow encode new memories into LTM.

Cognitive Load Theory

States that learning is constrained by limited processing capacity. The higher the cognitive load of the to-be-learned information, the harder it is to learn that information (in other words, minimizing the number of internal mental processes that take place in the ‘mind’ enhances the process of learning)

  • intrinsic cognitive load – caused by the inherent properties of the to-be-learned information and is unalterableother than by schema acquisition
  • extraneous cognitive load – results from the manner in which to-be-learned information is presented or from activities required of the learner

For additional reading and reinforcement:

Sensory memory is everything that you are exposed to at a given instant in time. The best way to think of sensory memory is to consider what happens as you watch a ice-hockey game. You are constantly aware of the location of all the players, but two seconds later as the play continues, you are unable to recall where each player was on the ice.

Short term memory (STM) does not have a lot of capacity and it doesn’t last very long (5-7 seconds). An example of short term memory is when someone gives you a phone number to remember and you forget it before you get to dial the number.

Long term memory (LTM) on the other hand lasts indefinitely, like your student ID number.

It used to be thought that the process of remembering was like an “assembly line” and that stimuli (words, pictures, actions etc.) passed from one station on the assembly line to the next (unidirectional flow of information)

Working Memory: A Modern Advance (needed because STM cannot explain the kind of processes that took place in it)

In the early 1990s, Alan Baddeley (University of York, UK) and his colleagues proposed a newer model of memory: with an additional component known as the working memory.