Comprehensive Memory Processes Notes

Memory Processes

Retrieval from Memory

• Retrieval from Short-Term Memory:
  • Serial process, not parallel.
  • Complete process - everything is retrieved, not just what's needed for the task.
  • Example: If someone memorizes items 8, 4, 6, 7, 2 and is asked if 6 was there, they will retrieve all numbers serially, not just 6.
• Retrieval from Long-Term Memory:
  • Much better if there is a cue available (e.g., category of the word).

Interference

• Retroactive Interference:
  • Newly acquired knowledge affects the retrieval of older information.
• Proactive Interference:
  • Information learned in the past affects the learning of new information.
  • Memorization interferes with already existing schemas in memory.
  • Proactive interference increases with the time between when information is memorized and when it is retrieved.
  • Proactive interference increases with the amount of previously learned information that can interfere with new information.
  • Proactive interference is related to the activation of the frontal cortex.
• Reducing Proactive Interference:
  • If the category of things being memorized changes (e.g., numbers to words), memorization success increases.

Position in Series

• Recency Effect:
  • Items near the end of a list are better recalled.
• Primacy Effect:
  • Items near the beginning of a list are better recalled.
• Serial-Position Curve:
  • Probability of recalling a given word based on its position in the series.
  • Recall is worst in the middle of the series.
  • Words at the end - proactive, but not retroactive, interference.
  • Words at the beginning - retroactive, but not proactive, interference.
  • Words in the middle - both types of interference.

Decay vs. Interference

• Decay Theory:
  • Information is forgotten because of gradual disappearance, rather than displacement.
• Short-Term Memory:
  • Decay has a relatively small effect on forgetting in short-term memory.
  • Interference accounts for most of the forgetting.
  • Even if both decay and interference contribute to forgetting, interference has the strongest effect.

Constructive Memory

• Memory is constructive - prior experience affects how we recall things.
• Autobiographical Memory:
  • Refers to memory of an individual’s history.
  • Is constructive.
  • One does not remember exactly what happened.
  • One remembers one’s construction or reconstruction of what happened.
  • Different in different life periods - middle-aged adults often remember events from their youthful and early-adult periods better than they remember events from their more recent past.

Flashbulb Memory

• A memory of an event so powerful that the person remembers the event as vividly as if it were indelibly preserved on film.
• A memory is most likely to become a flashbulb memory under three circumstances:
  • Important to the individual.
  • Surprising.
  • Has an emotional effect on the individual.
• The more a person is emotionally involved in an event, the better the person’s memory is for that event.

Memory Distortions

• Schacter (2001) - The Seven Sins of Memory:
  • Transience - memory fades quickly.
  • Absent-mindedness - brushing teeth after already having brushed them; people enter a room looking for something only to discover that they have forgotten what they were seeking.
  • Blocking - people sometimes have something that they know they should remember, but they can’t (tip-of-the-tongue phenomenon).
  • Misattribution - people often cannot remember where they heard what they heard or read what they read.
  • Suggestibility - if it is suggested to people that they saw something, they may think they remember seeing it.
  • Bias - people who currently are experiencing chronic pain in their lives are more likely to remember pain in the past.
  • Persistence – remembering not that much important details. Someone with many successes but one notable failure may remember the single failure better than the many successes.

Eyewitness Testimony

• People sometimes think they remember things simply because they have imagined or thought about them.
• When the perpetrator of a staged crime was not in a line-up, participants were susceptible to naming someone other than the true perpetrator as the perpetrator.
• Whether a given person is identified as a perpetrator can be influenced simply by who the others are in the line-up.
• Eyewitness identification is particularly weak when identifying people of a racial or ethnic group other than that of the witness.
• Stress: as stress increases, the accuracy of both recall and identification declines.
• Children: children of preschool age are much more susceptible to suggestive questioning.

Repressed Memories

• Memories being pushed down into unconsciousness because of the distress they cause.
• It is no clear evidence whether they actually exist or not.

Declarative vs. Procedural Knowledge

• Declarative Knowledge:
  • Knowing that.
  • Refers to facts that can be stated, such as the date of your birth.
• Procedural Knowledge:
  • Knowing how.
  • Refers to knowledge of procedures that can be implemented.

Imagery

• Mental representation of things that are not currently seen or sensed by the sense organs.
• May represent things that do not exist at all outside the mind.
• May involve mental representations in any of the sensory modalities, such as hearing, smell, or taste.

Visual vs. Spatial Imagery

• Visual Imagery:
  • Images that represent visual characteristics such as colors and shapes.
• Spatial Imagery:
  • Images that represent spatial features such as depth dimensions, distances, and orientations.
• Distinct Systems:
  • Patient with brain lesions could conduct rotations, mental scanning, size scaling, and state locations, but NOT recognize color and shape.

Dual-Code Theory

• We use two distinct codes for mental representation of knowledge:
  • An imaginal (analogical) code and a verbal (symbolic) code.
• Analog Codes:
  • Resemble the objects they are representing.
  • Mental images are analog codes.
• Symbolic Code:
  • A form of knowledge representation that has been chosen arbitrarily to stand for something that does not perceptually resemble what is being represented.

Processing of Information

• Verbal information seems to be processed differently than pictorial information:
  • People more easily recall the pictures when they are allowed to do so in any order.
  • People more easily recall the sequence of words than the sequence of pictures.

Propositional Theory

• We do not store mental representations in the form of images or mere words.
  • These images and words are epiphenomena—secondary and derivative phenomena that occur as a result of other more basic cognitive processes.
• Our mental representations more closely resemble the abstract form of a proposition.
• Logical Expression:
  • [Relationship\ between\ elements]([Subject\ element], [Object\ element])
  • Many possibilities to transfer into language: “The table is above the cat.”, “The cat is beneath the table.”, …

Propositional vs. Imagery Theory

• Limits of Imagery Theory:
  • People are unable to call up a precise analogical mental image.
  • Therefore they are unable to inspect the image in their mind if they don’t see it at that moment.
  • Mental representations of figures are not the same as percepts of these figures.
  • Propositional codes may influence imaginal ones.
    • This influence is especially likely to occur when the picture used for creating an image is ambiguous or rather abstract.
• Limitations of Propositional Theory:
  • We do not necessarily need a propositional code to manipulate information but can manipulate mental imagery directly.

Functional-Equivalence Hypothesis

• Visual imagery and visual perception are functionally equivalent, even if not identical.
• Supported by neuroimaging studies:
  • When people should view or imagine an image, the frontal and parietal regions in the brain are activated in both cases.

Mental Rotation

• Involves rotationally transforming an object’s visual mental image.
• When people are asked to compare whether a 2D/3D object and a rotated object are the same, the response time depends linearly on the number of degrees of rotation.
• Ability to conduct mental rotation is a part of human intelligence.
• Neuroscience results support functional equivalence between perception and mental imagery – the same parts of brain are involved.
• Some studies found that men are better in rotation tasks than women.

Representational and Spatial Neglect

• Spatial Neglect:
  • A person ignores half of his or her visual field.
• Representational Neglect:
  • A person asked to imagine a scene and then describe it ignores half of the imagined scene.
• These two types of neglect might occur independently.
  • That supports the hypothesis that perception and imagery are different processes.

Mental Models

• Knowledge structures that individuals construct to understand and explain their experiences.
• Help to explain haptic and auditory imagery.
• Support:
  • When people are given detailed descriptions for the spatial layout of objects, they infer additional spatial information not included in the descriptions, but they do not recall the given details well.
  • Both adding new information and not recalling details supports the idea that people rely on mental models.

Cognitive Maps

• Internal representations of our physical environment, particularly centering on spatial relationships.
• Landmark Knowledge:
  • Information about particular features at a location.
  • Based on both imaginal and propositional representations.
• Route-Road Knowledge:
  • Involves specific pathways for moving from one location to another.
  • Based on both procedural knowledge and declarative knowledge.
• Survey Knowledge:
  • Involves estimated distances between landmarks, much as they might appear on survey maps.
  • Based on both imaginal and propositional representations.

Cognitive Heuristics and Mental Maps

• People estimate the distance between two places to be shorter when traveling to a landmark than when traveling to a nonlandmark:
  • From a small town to the major city, the distance may seem smaller than otherwise.
• Right-Angle Bias:
  • People tend to think of intersections as forming 90-degree angles more often than the intersections really do.
• Symmetry Heuristic:
  • People tend to think of shapes as being more symmetrical than they really are.
• Rotation Heuristic:
  • People tend to distort the images as being either more vertical or more horizontal than they really are.
• Alignment Heuristic:
  • People distort their mental images to be better aligned than they really are (i.e., we distort the way we line up a series of figures or objects).
• Relative-Position Heuristic:
  • The relative positions of landmarks in mental images more accurately reflect people’s conceptual knowledge rather than reflecting the actual spatial configurations.

Memory and Driving

• Long-term: traffic rules
• Short-term: traffic signs
• Drivers remember risk situations
• People with dementia should not drive.

Organization of Declarative Knowledge

• Symbolic knowledge - knowledge of correspondence between symbols and their meaning.
• Concept:
  • An idea about something that provides a means of understanding the world.
  • Fundamental unit of symbolic knowledge.
  • Often, a concept may be captured in a single word, such as apple.
  • Concepts appear to have a basic level (sometimes termed a natural level) of specificity, a level within a hierarchy that is preferred to other levels.
    • A red, roundish edible object that has a stem is characterized as an apple and less likely as a fruit or a “red delicious apple”.
    • In general, the basic level is neither the most abstract nor the most specific.

Category

• A way to organize concepts.
• A group of items into which different objects or concepts can be placed that belong together because they share some common features or because they are all similar to a certain prototype.
  • The word apple can act as a category, as in a collection of different kinds of apples.
    • It also can act as a concept within the category fruit.

Types of Categories

• Natural Categories:
  • Groupings that occur naturally in the world, like birds or trees.
• Artifact Categories:
  • Groupings that are designed or invented by humans to serve particular purposes or functions.
• Natural and artifact categories are relatively stable, and people tend to agree on criteria for membership in them.
• Ad Hoc Categories:
  • Categories are created just for the moment or for a specific purpose, for example, “things you can write on.”
    • They are described not in words but rather in phrases.
    • Their content varies, depending on the context.

Feature-Based Categories

• The classic view of categories disassembles a concept into a set of featural components.
  • All those features are then necessary (and sufficient) to define the category.
    • This means that each feature is an essential element of the category.
• Defining Features:
  • The features uniquely define the category:
    • For a thing to be an X, it must have that feature. Otherwise, it is not an “X.”

Prototype Theory

• Things are grouped together not by their defining features but rather by their similarity to an averaged model of the category.
• Prototype:
  • An abstract average of all the objects in the category we have encountered before.
    • It is the prototype that objects are compared with in order to put them into a category.
• Crucial are characteristic features, which describe the prototype but are not necessary for it.
  • Whereas a defining feature is shared by every single object in a category, a characteristic feature need not be.

Game Prototype

• Consider the prototype of a game.
  • It might include that it usually is enjoyable, has two or more players, and presents some degree of challenge.
• But a game does not have to be enjoyable.
• It does not have to have two or more players.
• And it does not have to be challenging.

Classical and Fuzzy Concepts

• Classical Concepts:
  • Categories that can be readily defined through defining features.
• Fuzzy Concepts:
  • Categories that cannot be so easily defined, such as “game.”
    • Their borders are, as their name implies, fuzzy.
    • They tend to evolve naturally.
  • Fuzzy concepts and categories are built around prototypes.
    • An object will be classified as belonging to a category if it is sufficiently similar to the prototype – if it has a sufficient number of features shared between an object and the prototype.

Exemplars

• Exemplars - typical representatives of a category.
• Some psychologists suggest that instead of using a single abstract prototype for categorizing a concept, we use multiple, specific exemplars.

Combination of Feature and Prototype Theories

• Core:
  • Refers to the defining features something must have to be considered an example of a category.
• Prototype:
  • Encompasses the characteristic features that tend to be typical of an example (a bird can fly) but that are not necessary for being considered an example (an ostrich).

Theory-Based View of Meaning

• People understand and categorize concepts in terms of implicit theories, or general ideas they have regarding those concepts.
• People can distinguish between essential and incidental, or accidental, features of concepts because they have complex mental representations of these concepts.

Essentialism

• A view of meaning:
  • Certain categories, such as those of “lion” or “female,” have an underlying reality that cannot be observed directly.
• Essentialist beliefs about the characteristics of groups are often associated with the devaluation of these groups and increased prejudice.
  • These beliefs suggest that members of a particular group are intrinsically one way and can’t change.

Network Models

• Semantic Network:
  • Web of elements of meaning (nodes) that are connected with each other through links.
• Nodes:
  • Elements, they are typically concepts.
• Relationships:
  • The connections between the nodes.
    • Might indicate category membership, attributes, or some other semantic relationship.

Schemas

• Schema:
  • A mental framework for organizing knowledge.
    • It creates a meaningful structure of related concepts.
      • For example, we might have a schema for a kitchen that tells us the kinds of things one might find in a kitchen and where we might find them.
    • Similar to semantic networks, except that schemas are often more task-oriented.

Schema Information

• Schemas can include information about relationships, like relationships among:
  • Concepts (e.g., the link between trucks and cars).
  • Attributes within concepts (e.g., the height and the weight of an elephant).
  • Attributes in related concepts (e.g., the redness of a cherry and the redness of an apple).
  • Concepts and particular contexts (e.g., fish and the ocean).
  • Specific concepts and general background knowledge (e.g., concepts about particular U.S. presidents and general knowledge about the U.S. government and about U.S. history).

Scripts

• Script:
  • Contains information about the particular order in which things occur.
    • Scripts are much less flexible than schemas.
    • Scripts include default values for the actors, the props, the setting, and the sequence of events expected to occur.
• Experts share a jargon - specialized vocabulary commonly used within a group, such as a profession or a trade.
• Typicality Effect:
  • When a person is learning a script, if both typical and atypical actions are provided, the atypical information will be recalled more readily.
    • This difference is likely due to the increased effort in processing required for atypical information.

Procedural Knowledge

• Procedural knowledge representation is acquired through practicing the implementation of a procedure.
  • It is not merely a result of reading, hearing, or otherwise acquiring information from explicit instructions.
• Once a mental representation of nondeclarative knowledge is constructed (proceduralization is complete), that knowledge is implicit.
  • It is hard to make explicit by trying to put it in words.
  • Practice tends actually to decrease explicit access to that knowledge.
  • As your explicit access to nondeclarative knowledge decreases, however, your speed and ease of gaining implicit access to that knowledge increases.
  • Most nondeclarative knowledge can be retrieved for use much more quickly than declarative knowledge.
  • Involves the serial processing of information, in which information is handled through a linear sequence of operations, one operation at a time.

Nondeclarative Knowledge

• Nondeclarative knowledge may encompass a broader range of mental representations than just procedural knowledge:
  • Perceptual, motor, and cognitive skills (procedural knowledge).
  • Simple associative knowledge (classical and operant conditioning).
  • Simple non-associative knowledge (habituation and sensitization).
  • Priming (fundamental links within a knowledge network, in which the activation of information along a particular mental pathway facilitates the subsequent retrieval of information along a related pathway or even the same mental pathway).
• All of these nondeclarative forms of knowledge are usually implicit.
  • You are not aware of the different steps you carry out when you act, and it is hard for you to spell them out explicitly.

ACT (Adaptive Control of Thought) Model

• Declarative Knowledge:
  • Concepts are stored at various nodes within the network.
    • The nodes can be:
      • A node can be activated directly by external stimuli, such as sensations.
      • Or it can be activated by internal stimuli, such as memories.
      • It can be also activated indirectly by the activity of one or more neighboring nodes.
    • Nodes spread activation to another nodes.
    • Nodes that are more remotely related are activated to a lesser degree.

Procedural Knowledge in ACT

• Proceduralization:
  • The overall process by which we transform slow, explicit information about procedures (“knowing that”) into speedy, implicit implementations of procedures (“knowing how”).
• Knowledge representation of procedural skills occurs in three stages:
  • Cognitive Stage:
    • We think about explicit rules for implementing the procedure.
  • Associative Stage:
    • We consciously practice using the explicit rules extensively, usually in a highly consistent manner.
  • Autonomous Stage:
    • We use these rules automatically and implicitly without thinking about them. We show a high degree of integration and coordination, as well as speed and accuracy.

Problem-Solving Cycle

1. Problem identification: Do we actually have a problem?
2. Problem definition and representation: What exactly is our problem?
3. Strategy formulation: How can we solve the problem?
4. Organization of information: How do the various pieces of information in the problem fit together?
5. Resource allocation: How much time, effort, money, etc., should I put into this problem?
6. Monitoring: Am I on track as I proceed to solve the problem?
7. Evaluation: Did I solve the problem correctly?

Strategy Making

• May involve:
  • Analysis—breaking down the whole of a complex problem into manageable elements.
  • Synthesis—putting together various elements to arrange them into something useful.
  • Divergent thinking - you try to generate a diverse assortment of possible alternative solutions to a problem.
  • Convergent thinking - to narrow down the multiple possibilities to converge on a single best answer.

Turing Test

• Used to determine whether a computer is “intelligent”.
• The test is conducted with a computer, a human respondent, and an interrogator.
• The goal of the interrogator is to figure out who is human and who computer.
• The interrogator can ask the two parties any questions at all.
• The computer passes the Turing Test if an interrogator is unable to distinguish the computer from the human.