CH 6-8 Exam 2 APSY 381

Memory

The process of using info. that was obtained in the past in order to generate some cognitive function in the present

Memory Process

• Encoding- the initial process of info. that it is represented in the NS

• Storage- info. encoded by the NS remains encoded in some form for a longer duration than immediate processing

• Retrieval- being able to cognitively access stored info. for a given purpose

Measures of Memory

• Capacity

• Duration

Capacity

How much info. a memory sys. can hold

• Certain types of memory can process more/less info. compared to others

• STM < LTM

Duration

How long info. remains in a memory sys.

• Some types of info. are lost very quickly from memory, while others are retained for a lifetime

• A childhood phone # > This morning’s breakfast

Modal Model of Memory

• 3 types of memory w/ its own capacity & duration

1. Sensory memory

2. STM

3. LTM

• 2 different kinds of memory storage

1. For current tasks- STM

2. For long-term storage - LTM

Visual of the Modal Model of Memory

Sensory Memory

• Function: Briefly stores the info. just encoded by sensory organs

• Purpose: Holds memory in place before it is selected by attention & passed on to STM

Short-Term Memory

• Function: Store attended information from Sensory Memory for 15-30 secs

• Purpose: Hold info. that can be repeated/rehearsed for encoding

  • Only encoded info. is moved to LTM for future retrieval

  • Ex. repeating a phone number someone just told you for recall at a later time

Chunking

Any combination of letters, numbers, or sounds that constitute a meaningful whole

• The capacity to chunk info. into larger units depends on engaging LTM where patterns of previously encountered combinations are held.

• The approx. capacity of auditory STM is 7 +/ -2 chunks

• Ex. PEMDAS: Parentheses, exponents, multiplication, division, addition, subtraction

Duration of STM

Theoretically forever, as long as you can rehearse the info.

Rehearsal

The repetition of info. in STM which reactivates the initial encoding

• Ex. Grocery trip: milk, eggs, bread

Proactive Interference

Info. causes you to forget something you could learn in the future

• First learn (material A) > then learn (material B)

Retroactive Interference

Info. causes you to forget something in the past

• Then learn (material A) > first learn (material B)

Working-Memory Model

… STM is an active workspace in which info. is manipulated for a given task

Visual and Verbal Task Exp.

… suggest that visual and auditory memory are processed separately from one another and do not interfere w/ one another

Visuo-Spatial Sketchpad

• Visual component of the WM model

• Hold info. in the NS while also having the ability to analyze & manipulate it

Phonological Loop

• Auditory component of WM model

• Allows auditory info. to be repeated so it can be used and/or analyzed

Central Executive

• Coordinates b/w the phonological loop and the visual sketchpad

• Determines what info. makes it into STM in the first place

  • Research suggests that ind. differences in STM capacity (the fact that some people can remember more items than others) may be due to differences in the ability to filter out irrelevant info. from memory

Individual Differences

… correlated w/ measures of general intelligence

• Relationship likely due to developmental factors- more space in working memory could bolster other cognitive capacities including: visuo-spatial capacity, math performance, reasoning ability

Neural Basis of STM/WM

• Auditory WM activates auditory regions of the brain (temporal lobe)

• Visual WM activates visual regions of the brain (occipital lobe)

• Prefrontal cortex & frontal lobe may be where the central executive is located

Neurological Differences in STM & LTM

Behavioral differences b/w STM & LTM suggest that there may be distinct memory sys.s

• Amnesia

Amnesia

Severely impaired LTM due to brain trauma

Retrograde Amnesia

Difficulty remembering events that occurred leading up to the event

• Memory lost before the event

Anterograde Amensia

Difficulty remembering any new info. they encounter

• Memory lost after event

Case Studies

• H.M- Deficits in LTM

• C.W - Deficits in both STM/LTM

• K.F - Deficits in STM

Encoding Specificty

• Serial Position Effect- primacy and recency effects

• Levels of Processing- superficial, intermediate, deep, we remember more when we deeply process the meaning of something

• Memory Retrieval- mnemonics help

  • The brain encodes associations b/w experiences & the world

  • Experiences <> world

    • Allows us to make predictions about or environment

Different Types of LTM

• Explicit/declarative memory

• Episodic memory

• Semantic memory

  • Episodic > semantic

• Implicit memory

Explicit/Declarative Memory

Memories that we can verbally describe or declare

Episodic Memory

Memories of event that have happened directly to us is in our lives

• Can recall sensory info. in sequence

• Likened to a mental time travel

Semantic Memory

Memoires w/ info. w/o sensory details

• The meaning of words, your address, phone number…

Implicit Memory

• Info. that is encoded & stored, then retrieved outside of consciousness

• Includes procedural memory as well as prejudice > automatic neg. judgements of an ind/gp, even if the judgement/attitudes are outside of conscious awareness

Procedural Memory

Learned abilities to perform an automatic behavior/action

• Walking, swimming, bicycling

• The brain has encoded patterns of movements

• Is particularly immune to forgetting compared to other types of memory

Familiarity Effect

People tend to rate something more favorably if they have encountered it before (music, photos)

• Even of they don’t remember seeing them

Propaganda Effect

Ind.s presented w/ statements that they had heard before were more likely to rate them as true compared to never-before-heard statements of accuracy

Autobiographical Memory

Episodic memories about events we’ve experienced & semantic memories of basic facts about ourselves

Studying ABM

• Cannot study ABM like other types

• Must rely on retrospective reports through personal interviews

• Has limitations:

  • Lack of control, order of encoding, undetermined accuracy

Directive ABM

Allows for retrospection on past experiences to inform & guide current actions

Social ABM

Allow ppl to share experiences & create social bonds

Self-Representational ABM

Allow ppl to look into the past to inform behavior to act consistently w/ a self image & maintain a stable identity

Self-Memory System

• AB knowledge base- stores info. & facts about past life events

  • Comparable to LTM & WM sys.s

  • AKA cold storage- active workspace for pulling up memories

  • Goal: coherence- supporting our existing beliefs about ourselves & the world

• Working Self- a set of current personal goals that determine how the base is accessed

• Major distinguishable periods in our lives that have a specific beginning & end time (grade school, living in a city, first job)

ABM Base

Lifetime periods - general events

• Relationship theme < first date, second date

• Work theme < working in the corner office

  • Event-specific knowledge

Decay of SMS

Most events we experience are not stored as episodic memories- even if we keep some semantic memories, we may not have episodic elements

• The dissolution of event-specific knowledge, leaving only general events or lifetime periods

• Maintain episodic memories for hours or days > most fade into semantic memories > some are completely forgotten

Memory Retention

• Emotion

• Importance

• Life Stage

  • Importance of an event has a large impact in whether it is remembered

  • We tend to remember both pos. & neg. events:

    • 1st kiss & birth of a child

    • Death & breakup

Infantile Amnesia

Most adults remember very few or no episodic memories before the age 2-4 yrs, does not affect implicit memory as much as explicit

• Hippocampal change

  • The hippocampus (LTM consolidation) is underdeveloped until age 4

• Neurogenesis

  • Production of new neurons

  • Building the brain could cause memories to be overwritten

• Lang. abilities

  • Juvenile lang. abilities

  • Ability to reconstruct episodic memory may depend on lang. for “story telling”

• State-dependent learning

  • Differential emotional reactions to events

  • Highly emotional events remembered…inability to retrieve old memories

Flashbulb Memories

Memories of a high-emotion event that many people experienced at the same time

• 9/11, Challenger disaster, MLK Assassination, JFK Assassination

• Ppl tend to believe that their memories of these events

  • Maintain vivid details of events

  • Are branded into memory permanently

  • Do not decay over time

• Not immune to forgetting, but are better remembered < provoke an emotional response, leading to better encoding, thinking & talking about them promotes consolidation

• Culturally dependent:

  • Event relevance & subsequent flashbulb memory formation depends on one’s identity

Constructive Nature of ABM

• Memories are interpretations of events & the world

• Can be flawed & false, much like perceptual processes

• Eyewitness testimony is inherently flawed

• Lang. & emotions can bias “eyewitnesses”

Ch 6 Summary

• 6.1 Encoding is the initial processing of information. Storage is how
  inform is maintained across time, and retrieval is your ability to access the stored information. Memory can be measured by examining the capacity and duration of different systems.

  6.2 The modal model of memory has three components: sensory, short-term, and long-term memory. Sensory memory refers to the initial processing of information from our sensory systems (e.g., visual and auditory). Information can be maintained in short-term memory if it is actively rehearsed but will likely be lost otherwise. Information is then passed to long-term memory, which can hold large amounts of information

  across your lifespan.

• 6.3 The working memory model for short-term memory has been theorized to have three distinct stores of information to explain how you actively think and cognitively manipulate information. These three stores are the visuo-sketch pad, phonological loop, and central executive.

  6.4 The neural basis of short-term/working memory is not located in one specific region. The modality-specific regions are found to be active in working memory tasks. Frontal lobe regions are thought to be primarily responsible for central executive tasks.

  6.5  Recurrent neural networks are a class of neural-network models

  applied to sequential data that contain 'recurrent' nodes that loop their output back into themselves as inputs, allowing them to process past and current inputs simultaneously.

Ch 7 Summary

• 7.1 Neuropsychology gives us information about the dissociation of short-term, long-term, episodic, and semantic memory.

  7.2 Rehearsal is essential to moving information from short-term to long-term memory. Certain conditions make information more likely to be moved into LTM, including order to presentation, level of processing/encoding, and the environment in which encoding/retrieval took place. Additionally, the times and level at which information is repeatedly observed impacts LTM.

  7.3 Explicit/declarative memories are those that we can verbally describe,  episodic memories are those of events that happened directly to us in our lives, and semantic memories are memories with information, but no sensory detail. Implicit memory is memories that we may not be consciously aware of, but can be assessed using the Implicit Association Test.  These types of memory have neural and behavioral differences.

  7.4 Synaptic and system consolidation allows the brain to condense memories for storage in LTM (sometimes indefinitely). This occurs through the creation of new connections between neurons. Although the role of relevant neural structures is debated (i.e., the hippocampus), this process allows the brain to maintain memories across time.

Ch 8 Summary

• 8.1 Autobiographical memory (AM) serves as guide for our intentional action and can increase social cohesion through shared experience and a stable self representation. AMs can be organized into broad tiers of lifetime periods, then more specific related sequences of general events, and finally into more detailed memories of event-specific knowledge.

  8.2 We do not retain memories from early life (~before the age of 4 years). This could be due to changes in the brain, social experience, and/or cognitive development.

  8.3 Emotion leads to better memory encoding and retrieval due to increased amygdala activation. Highly emotional events can lead to flashbulb memories, which are more resistant to forgetting, but can still be impaired over time. Despite their fallibility, people are highly confident of these memories.

• 8.4 Memories are subjective interpretations of events. They are vulnerable to manipulation including the introduction of false information and the fabrication of false memories. This is especially consequential for the legal system that is highly dependent on eye-witness testimony. Errors in eye-witness memory and subsequent convictions has been addressed by the Innocence Project, which aims to exonerate wrongfully convicted individuals who were prosecuted based on eye-witness testimony.

  8.5  The PFC, medial temporal lobe (specifically the hippocampus), and amygdala are all involved in AM construction, retention, and retrieval.