Problem 1 Flashcards
Working memory
The active maintenance + manipulation of short term memory
–> STM here, is used to maintain info for a brief period
ex.: repeating a phone number constantly before being able to put it in phone
Cognitive/Executive control
Refers to the manipulation + application of working memory to guide behavior in a constantly changing world that includes
a) planning
b) attention
c) mental flexibility/task switching
d) response + cognitive inhibition
Long term memory
days to years
Permanent or near permanent storage of memory that lasts beyond a period of conscious attention
–> semantic + episodic memories are subcategories
Short term memory
sec to min
Temporary memory that is maintained/stored through active rehearsal
- -> used as the site of working memory operations
- -> are transient, existing only briefly
Transient memories
Short lasting mental representations, sometimes persisting for only a few seconds
–> short term + sensory memory are subcategories
Sensory memory
millisec. to sec.
Brief, transient sensations of what one has just perceived
–> there is a form of sensory memory for each sensory modality
ex.: Iconic visual store/Visual sensory memory, Echoic store
What are the characteristics of the STM ?
- Limited capacity
- Effortlessly available
- Contains active contents of consciousness
- Things are forgotten quickly
Millers “Magic number” /Span of immediate memory
Suggestion that the capacity of the short term memory is limited to 7 items
–> 5-9
What are the characteristics of the LTM ?
- Unlimited capacity
- Access requires effort
- Contains contents that aren’t necessarily currently in consciousness
- Things are forgotten more slowly
What is the STM limited by ?
- By what you can pay ATTENTION to
ex. : if you get distracted, you might forget what you paid attention to previously - CAPACITY
–> magic number
What is key to optimizing the amount of information that can be maintained in STM ?
The recoding of information / Chunking
–> the limit to short therm memory is not an absolute amount of information but a limit in the number of UNIQUE CONCEPTS or links to long term memory that can be held active
Baddeley’s working memory model of working memory
Describes what goes on inside the WM, containing two separately stored WM buffers
a) Visuospatial sketchpad
b) Phonological loop
Atkinson-Shiffrin modal-model of memory
Info is first stored in sensory memory
- Items selected by ATTENTIONAL processes are moved into STM storage
- REHEARSED items are moved into LTM storage
–> at each stage info is lost by decay, interference or combination of both
Visuospatial sketchpad
Maintains VISUAL + SPATIAL images for manipulation
–> right VLPFC
Phonological loop
Maintains AUDITORY/VERBAL memories for manipulation by means of internal speech which is used during rehearsal
–> left VLPFC
Central executive/Supervisory attentional system
Working component of the WM
Monitors + manipulates both of the WM buffers and keeps the WM therefore updated by
- Adding to + deleting from the items in buffers
- Receiving + evaluating sensory info
- Retrieving info from LTM
- Deciding which info is necessary for which task
=> guides behavior
Why is internal speech key to the phonological loop ?
- People with slow rates of speech but normal intelligence will do worse on STM verbal memory tasks
–> the repetition of sequences in the head will take longer
- If internal rehearsal is disrupted, phonological storage cannot occur
Word length effect
As the length of the words increases, the number of words you can remember declines
–> multi-syllable words take longer to rehearse
ex. university, auditorium vs bat, kit
Delayed non match-to-sample (DNMS) task
Test of visual memory in which a subject must indicate which of 2 novel objects is not the same as one that was recently seen
–> reward is given
Is WM a place or a state ?
WM describes an active STATE for memories otherwise resident in LTM but not accessible to conscious reflection
–> requires manipulation until they are activated
ex.: paintings in a museum going from obscure to illuminated, their place being unchanged
Model of STM
Cowan
States the several chunks of info in the LTM can be activated as the focus of current attention
–> suggests that the STM has 2 different types of activated states
Multi store models of memory
- Imply the existence of 2 or more different places for memories to be stored
- Capacity limits are governed by the rate at which info is rehearsed, forgotten, transferred
–> place based
Unitary store models of memory
- Imply there is only ONE place for memory, although the memories can be in various states
- Capacity limits arise from the bandwidth of attention that can be focused on activated areas of LTM
–> state based
Tower of hanoi
Requires manipulating the WM to a great extent, because one has to remember at least 3 things at all times
- What subgoals have been accomplished
- What subgoals remain
- What the next subgoal is to be addressed
Wisconsin card sorting test
Requires
- Learning a rule + keeping it in mind
- Learning to change the rule + keeping track if the new one without confusing it with the old one
–> Mental flexibility/Task switching
Stroop task
The names of colors are printed from top to bottom, each in a color that does not correspond to the name
–> requires controlled processes
Which 2 types of processes occur in parallel, competing to influence our behaviors ?
a) automatic processes
b) controlled processes
Automatic processes
Are triggered by situational cues
–> deeply ingrained, reflexive + typically occur with minimal conscious awareness
–> do not interfere with concurrent activities
Controlled processes
Are mediated by the “Supervisory attentional system” that modifies behaviour when the automatic responses are inappropriate
ex.: paying extra attention in england, because cars drive on opposite sides
Intelligence
Refers to the capacity for leaning, reasoning + understanding
–> associated with a strong WM, especially the control + manipulation of larger numbers of
a) rules
b) concepts
c) goals
d) ideas
Prefrontal cortex
Refers to the most anterior section of the frontal lobes
–> critical for WM + executive control
What does damage to the frontal lobes lead to ?
- Dysexecutive syndrome
- Deficit in WM + executive function, but normal LTM
- Perseveration
- High degree of distractibility
Dysexecutive syndrome
Disrupted ability to think + plan
Perseveration
Failing to learn a new rule and instead persisting in using an old rule despite repeated feedback indicating that the old rule is no longer correct
What are the main regions of the Prefrontal cortex ?
- Orbital
- Medial
- Lateral
a) Dorsolateral (DLPFC)
b) Ventrolateral (VLPFC)
In what way do the neurons of the PFC fire ?
- The neural activity acts as a temporal bridge between stimulus cues and the response
- Its neurons fire to different kinds of stimuli/ at different times (Cue, delay, response)
- “Delay neurons” are individually tuned to different directional movements
What is the key cognitive contribution of the DLPFC to the WM ?
The ability to sustain activity despite distractions
Why is the persistent activity in the DLPFC critical for executive control processes ?
Top down signals from the DLPFC have a diverse range of roles in controlling behaviour
–> those signals might enhance + maintain internal representations of relevant stimuli in different cognitive centers until they are need for different actions
What is the role of the Ventrolateral PFC ?
- Supporting the active controlled encoding + retrieval of information
- Contributing to the roles of the visuospatial sketchpad + phonological loop
–> MAINTENANCE
What is the role of the Dorsolateral PFC ?
Central executive
Supporting higher order cognitive-control functions
right: all monitoring processes
left: verbal materials
–> MANIPULATION + MONITORING of stored information
What does the state based theory of WM model suggest ?
- WM emerges from a network of brain regions
- This network of brain regions send + receive controlling info to + from PFC
- Together, they accomplish the active maintenance of internal representations
How are abstract to more specific goals represented in the brain (PFC) ?
The flow of control within the Frontal cortex goes from the most anterior regions to the more posterior regions
- -> more abstract = anterior PFC
- -> more specific = posterior PFC
BUT: Posterior parts develop first
Tip of the tongue Phenomenon
Refers to the feeling of trying to recall information
ex.: Seeing someone at a party that seems familiar but yet you can’t remember how you know him/her
–> not using the DLPFC as we didn’t MANIPULATE the retrieved info
Which brain parts are active during the encoding of new verbal information ?
Anterior PFC: Activated during tasks for SEMANTIC processing
Posterior PFC: Activated during tasks for PHONOLOGICAL or VISUOSPATIAL processing
What symptoms do schizophrenia patients display ?
Disturbances in cognition + memory, especially WM + executive control
- -> due to dysfunctional DLPFC, but intact VLPFC
- -> no mental flexibility
How do schizophrenia patients try to make up for their dysfunctional DLPFC ?
By engaging greater VLPFC involvement
–> less efficient though
What is related to the emergence of the cognitive deficits seen in schizophrenia ?
Genetic mutations affecting the dopamine activity in the PFC, resulting in too much release of dopamine
–> less affective/mutated COMT results in less PFC activity
Which deficits do ADHD patients display ?
Deficits in mental calculations + sustained focus of attention
Where do the deficits displayed in people with ADHD stem from ?
- Smaller PFC
- “Noisy” input signals from basal ganglia
- -> basal ganglia can’t accurately indicate what is or isn’t important to attend to
Learning
Refers to the process of acquiring information
- -> happens when memory is strengthened by repetition
- -> performance improves by more exposure
ex.: we remember the details of a persons face better by seeing it more
Memory
Refers to the interaction of subsystems, each with its own memory store
Flashbulb memories
Refer to the vivid memories of the circumstances surrounding shocking/emotionally charged news
- -> confidence in the recollection even years later is high
- -> no more accurate than other memories
What are the hypothetical stages of memory ?
- Encoding
a) acquisition
b) consolidation
- Storage
- Retrieval
Encoding
Information is translated into a from that can be processed mentally
–> so that it can be placed in LTM
Acquisition
Substage of “Encoding”
Registering the inputs of the information in sensory buffers + sensory analysis inputs
Consolidation
Substage of “Encoding”
Creating a stronger representation of the information over time
–> Hippocampus activates the neocortex which leads to strong connections between the two
Storage
Creating + maintaining a permanent record
–> refers to the result of acquisition + consolidation
Retrieval
Utilizing stored information to create a conscious representation or to execute a learned behaviour
Peterson + Petersons experimental paradigm
Refers to a test used to measure how long it takes to forget information.
Participants were presented with 3 letter strings.
A light cued them to recall the letters
–> DISTRACTION led to an ultimate decay of the info
Which factor affects recall ?
The number of intervening items
–> 16-digits task
Serial position effect
Refers to the pattern/order for what we typically remember
ex.: when we forget our shopping list at home, this
determines which ingredients we might remember
Primacy effects
Reflects the transfer of info from STM to LTM
ex.: remembering the items at the top of the list
Recency effects
Reflects retention of info in STM
ex.: remembering items at the bottom of the list because just recently seen
–> distracting tasks will eliminate the recency effects
Bit
Elementary piece of information
ex.: every letter of the word “cerebellum”
Chunk
Unit composed of bits (meaning)
ex.: full word “cerebellum”
Why is chunking so helpful when it comes to recalling information ?
- Chunked info can be essentially unchunked, unveiling every information it contains
- Can yield more bits of info than could normally retained
What are the key features of the sensory memory ?
- Fast decay
- Larger capacity compared to STM
- Storage of sensory representation of info as opposed to semantic
Levels of processing model
Deep/Elaborate rehearsal + encoding creates meaningful codes that relate information directly to previously acquired knowledge
–> how info is processed affects how it is remembered
Memory store
Refers to the mental “location” in which the encoded info is held
When does forgetting occur ?
Due to problems with any of the 3 mental processes involved in memory
- experienced, but not encoded
- encoded, but not stored
- -> “da rein, da raus” - encoded + stored, but can’t be retrieved
N-Back task
Participants are presented with a sequence of numbers one-by-one. For each number, they need to decide if the current one is the same as the one presented “N” (certain number) trials ago
Delayed saccade Task/
Delayed response eye gaze task
- The monkey fixates on a central spot on the screen while a cue flashes in the one of the corners
- During a delay period, the cue disappears and the monkey remains fixated on the central point
- Finally, when the central spot turns off, the monkey looks where the cue previously appeared
- -> in the “Anti-saccade task” the monkey is required to look in the opposite direction of the cue
