Working Memory: Types and Processes

Working Memory

• Memory involves storing past experiences and information, and has two measurable components
• Memory duration refers to how long info can be held
• Memory capacity refers to the amount of information that can be held
• Memory is evolutionarily advantageous and present in almost all animals
• Memories are used and obtained through three processes
• Encoding is the first step, and transforms information into a comprehensible format
• Storage involves retaining information
• Retrieval is locating and recovering information for immediate use

Types of Memory Systems

• Sensory memory is a high-capacity system that records information from each of the senses
• Sensory memory has a large capacity, but its storage is temporary
• Short-term memory has a short duration and a small capacity
• Short-term memory lasts approximately 30 seconds
• Short-term memory can hold 7± 2 chunks, also known as memory units
• Long-term memory has a long duration and a large capacity
• Long-term memory can last up to a lifetime and has an endless capacity

Atkinson and Shiffrin Model (Memory Model)

• Information from the environment is received and stored in sensory memory, then transferred to short-term memory
• Ideally, items are remembered well enough to keep them in long-term memory
• Control processes like rehearsal are necessary; without them, chunks of information are lost at any step
• This model is based on the idea that mental processes are computer operations that serially process information
• The flow of information is: Sensory input to STM to LTM

Limits on Encoding to LTM

• Encoding limits are influenced by multiple factors
• Semantics, or word meanings, are important
• Interference occurs when information is in the same semantic category
• A word's position in a list affects how likely it is to be remembered, thus forming a U-shaped curve (first & last items)
• Primacy effect enhances memory for items that are first on a list
• Recency effect enhances memory for items that are last on a list
• Proactive interference occurs when old information blocks new information from being retained

Working Memory vs. Short Term Memory

• The brain doesn't work like a computer in a linear fashion; however, the Atksinson Shifrin model did contribute three points:
  • STM and LTM processes are different
  • STM is affected by the properties
  • LTM storage is affected by how our STM process
• Working memory is a brief, immediate memory for a limited amount of material being processed, keeping information accessible
• The working memory approach posits that immediate memory is part of a larger system which stores and manipulates information while performing tasks
• STM is a passive process where information simply "goes in."
• Working memory is an active process where information is constantly being handled

Baddeley & Hitch’s Working Memory Model

• Working memory has different components with interrelated functions
• Phonological loop processes language and sounds (external & internal), but it has a limited capacity
• The phonological loop is used for: learning languages, self-instruction/mental reminders, math calculations, and counting
• Subvocalization refers to the little voice inside your head while reading
• Acoustic confusions occur when similar-sounding stimuli is confused
• Visuospatial sketchpad processes visual and spatial information
• Visuospatial sketchpad is used to: break down scenes into objects and landmarks, store mental images and relative positions of objects, and allows for navigation
• The right hemisphere is activated, specifically the occipital lobe (processes visual info) and the frontal lobe (responsible for attention/focus)
• VSS tasks require the processing of visual stimuli and directing focus to stimuli to remember
• Visuospatial sketchpad can work simultaneously with the phonological loop
• The visuospatial sketchpad also has a limited capacity
• The Episodic buffer briefly holds material from different memory systems and combines everything
• Episodic buffer helps to interpret earlier experiences to solve problems and plan future activities
• It also allows binding of concepts that did not make sense on their own
• Meaningful chunks that are easier to remember are produced
• The Central Executive allows the direction of attention to specific tasks and allows or prevents responses from occurring
• The central executive is the CEO, and tells you how to use information, but doesn't keep the info itself
• It allows planning of how to process and learn new information
• It also helps suppress irrelevant information
• Frontal cortex is activated, which is responsible for attention tasks

Phonological Loop + Visuospatial Sketchpad vs Central Executive + Episodic Buffer

• Phonological loop and visuospatial sketchpad are for storing information
• Central executive and episodic buffer are for processing information

Working Memory Differences & Mental Illness

• Depression results in worse performance on memory tasks involving the phonological loop, visuospatial sketchpad, and central executive
• Rumination (excessive worrying) causes concentration issues (C.E)
• ADHD results in worse performance on visual and verbal memory tasks.
• Smaller PL and VSS cause overstimulation which causes forgetting
• Deficits in the C.E cause worse attention when planning or multitasking
• Anxiety results in rumination which causes concentration issues, and is similar to depression
• Anxiety causes the C.E to focus on nerves and not properly process other info

Quick Recap: Memory Models

• ASM is the three step model: Sensory to short-term to long-term, and rehearsal helps retain info
  • Semantics, serial position, and proactive interference affect STM
  • Although not used now, these models did contribute to the understanding of the systems!
• BHWM is another memory model where: Working memory = CEO + PL + VSS + EB
• Most systems have a limited capacity, and memory duration depends on how much you process and rehearse

Long-Term Memory

• Long-term memory is a high-capacity storage system that contains a lifetime of memories and experiences
• Long-term memory has a long duration and large capacity
• There are three components of long-term memory
  • There are a series of episodes in the LTM

Components of Long-term Memory

• Episodic memory stores personal memories of life events
• Procedural (implicit) memory stores non-verbal, procedure-based memories
• Semantic memory stores organized, general information/knowledge

Methods to Store Information Long Term

• Encoding is the process of obtaining and transforming information into a format that can be understood
• A levels of processing approach suggests that deeper processing leads to more permanent retention
• The ways to make information more meaningful are elaboration, distinctiveness, and self-reference
• Elaboration entails connecting a stimulus to other information
• Distinctiveness entails making a stimulus less similar to other memories
• Self-reference entails connecting a stimulus to yourself
• This works best due to the presence of cues (behavioral triggers) that easily remind one of info
• Encoding specificity states that the context in which information is learned affects the ability to recall it
• Studying in the same environment as testing can improve recall
• Emotional context refers to how the emotional state during learning affects recall
• Emotionally charged words are more easily remembered given their emotional significance

Retrieval of Long Term Memories

• Retrieval is the process of locating and recovering information for immediate use (LTM to WM)
• Explicit memory involves memories that require active and conscious recall of information
• Explicit memory tasks involve being presented with stimuli and asked to recall actively
• Recall involves determining how many stimuli can be remembered, and the fill-in-the-blank tests are an example
• Recognition involves determining whether a stimulus was previously seen, and multiple choice are an example
• Implicit memory involves memories that emerge automatically or unconsciously and influence behaviors
• Implicit memory tasks involve being shown a series of stimuli and then being asked to do another task that doesn’t require recall/recognition
• Repetition priming occurs when prior exposure to a stimulus influences future recognition or response unconsciously

Implicit vs Procedural Memories

• All procedural memories are implicit, but not all implicit memories are procedural
• Implicit memories are a broad category with subtypes
• Conditioning is an example of subtype
• Priming is a prior exposure that influences a response
  • Priming doesn't always require repeated exposure and can arise after seeing something once

Anxiety Disorders and Memory Tasks

• There are significant differences in explicit memory recall tasks
• Anxious people typically remember negative/unpleasant words

Types of Amnesia

• Amnesia is a deficit in episodic memory
• Retrograde amnesia involves losing past memories
• Anterograde amnesia involves being unable to create new memories
• The hippocampus is important for forming and retaining memories, such as in anterograde amnesia

Dissociation

• Dissociation refers to the differences in performance in explicit vs. implicit tasks
• Explicit memory declines as we age, but our implicit memory doesn’t
• Amnesia is shown by the H.M case, procedural memories are implicit

Autobiographical Memory

• Autobiographical memory stores self-referential memories of events and issues that define identity
• Typically, memories are accurate, with any inaccuracy stemming from mistaking minor details or blending information from different events

Episodic Autobiographical Memory

• Episodic memory stores personal memories of life events
• Autobiographical memory stores personal memories of life events, emotions, statements, and procedural memories, also known as meaningful moments

Schema

• Schema represents general knowledge or expectation about someone or something
  • The term "SPORE" denotes Self, Persons, Objects, Roles, and Events
• Script is a well-structured sequence of events that occur in a specific order, with the "E" in SPORES representing the schema-event

Integrating Information

• It is common to integrate information in a schema-consistent way, according to what we believe to be appropriate

The Constructivist Approach

• Knowledge is built through the combination of new information (WM) and experiences (LTM)
• When looking back at memories, it's common to rebuild them
  • LTM leads to "editing", leading to new information in the WM

Memory Distortions

• Retroactive interference occurs when new information interferes with retrieving old information
• Source monitoring occurs when trying to remember the source of a memory
• Reality monitoring occurs when trying to remember whether or not an event was real
• Consistency bias is aligning past experiences with current beliefs

Flashbulb Memory

– Refers to the initial memory of an event

Eyewitness Testimony vs. Types of Bias

• Factors affecting the reliability of eyewitness testimony are stressful circumstances, social pressure, time between the crime and interrogation, and positive feedback
• Misinformation effect is when exposure to potentially misleading information can lead to inaccurate recall
• Own-ethnicity bias leads to people being better at recognizing people in our ethnic group compared to other ethnic groups
• Retroactive interference is literally a skill issue and an internal issue
• Misinformation effect relies on outside information which makes it an external issue

The Power of Expertise

• Expertise is a demonstration of impressive memory abilities and consistently exceptional performance in a certain task
• Increased skill practice, (rehearsal) leads to easier retrieval, (distinctiveness) along with more knowledge
• Use of vivid imagery in order to recall memories
• Expertise is context specific, such that excelling in one task does not imply competence in another

Improving Memory

• Distributed practice produces a better recall than massed learning
• Testing the to-be-learned material improves memory of it
• Mnemonics are mental strategies aimed to improve memory and recall
• The deeper the processing, the better the recall
  • Distinctiveness, elaboration, self-reference, and encoding specificity all help
• Total time hypothesis states that the amount of material learned correlates with the amount of time spent studying
  • However, the quality of studying is more important than the amount of time spent studying

Mnemonic Devices

• The loci method uses a mental room to associate information with familiar places
• The Keyword method Links a word to a similar sounding word
• Chunking combines smaller units into larger units
• First letter technique uses first letter of a word to create a new word or sentence
• Narrative involves using a story to explain a concept
• Hierarchy method organizes concepts into categories

Memory Types

• Retrospective memories are memories of the past
  • Episodic, procedural, and semantic
• Prospective memory is memory for something in the future
  • They focus on actions rather than information, so basically a reminder
• Absentmindedness is a memory lapse; occurs when we’re not fully focused
  • Prospective memories also require distributed attention, such that one needs to focus on the task at hand, while keeping in mind what will be needed in the future

When Absentmindedness Develops

• Absentmindedness can develop when a ritual is disrupted
• Absentmindedness can develop is we’re in familiar situations as the environments triggers us to do anything except focus on the protask
• Absentmindedness can develop when distractions are present

Improving Memory Effectiveness

• Use external memory aids which are external devices that help your memory
• To maximize effectiveness: Make them distinctive and easy to see
• Place the aids somewhere that can be easily located
• The brain should be used
• Don’t over-rely on the devices

Metacognition

• Metacognition is knowledge and control of cognitive processes, otherwise known as thinking about thinking
• Central executive is involved to focus attention
• Metamemory is self-knowledge and control of our memories, otherwise known as "will I remember this later"