PSYC 213 Chapter Notes - Chapter 5: Frontal Lobe, Thiamine, Olfactory Bulb
28 May 2018
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Chapter 5: Memory Systems
Understanding Memory Systems
• Different types of memory;
o Working, episodic, semantic, procedural memory & perceptual representation system
o Procedural memory is oldest evolutionarily
• William James: at the origin of first strong distinction between short (STM) and long-term
memory (LTM)
o Primary memory: where info initially stored
• Available for consciousness, attention, & introspection
o Secondary memory: long-term storage for memories
• In order to use information from secondary memory, must be brought to primary memory
(brought to consciousness)
Modal Model of Memory --Sensory Memory
• Modal model of memory: three interconnected memory systems --sensory memory, short-term
& long-term memory
o Memory model, well known
o Atkinson & Shiffrin
• Information from outside world first processed by senses
o Information stored very briefly in iconic memory (visual input) or echoic sensory
memory (auditory input)
o Sensory memory: used as buffer system for stimuli received through senses
• Has ability to register large amounts of information
• But decays very quickly (iconic: 1s limit & echoic: 2s)
o Not all information from sensory memory enters short-term memory
• Study by Sperling: participants flashed matrix of 9 letters, in rows of 3 for brief moment (50ms)
o Seminal search
o Partial report task: immediately recall one row of letters
• Once disappears, signal tells which row to recall
• Relates to ability to remember exactly what the stimulus was and where located
after seeing it for only a short moment
• Very good accuracy (high performance)
o Whole report task: asked to recall all 9 letters
• Very poor performance
• This paradigm was used to determine the time course of sensory memory (how long lasts)
o Varied length of delay before which tell what row to recall
o Rate of decay relatively fast
• After 1s delay, ability to recall 3 letters no better than ability to recall all 9
immediately
• Time course for forgetting
• Reflects that:
o Sensory system able to store large amounts of information at single glance
o Sensory memory exists for all 6 senses
Short Term Memory
• Receives information from both sensory memory & long-term memory in Atkinson & Shiffrin's
modal model of memory
o Attended info enters short-term memory
o Retained there for short time (18s upper limit)
o Information decays, unless adequately rehearsed
o 4 chunks of information at a time; limited
• Miller: capacity for short-term memory in humans is 5-9 items
o Have seven-digit phone numbers
• Consolidation: process of stabilizing memory traces to form long-term memories
o Promoted by rehearsal
• Other ways of increasing capacity of short-term memory
• Chunking: arranging elements in groups that can be more easily remembered
• Acronyms, etc.
Long-Term Memory
• Final component of modal model
• Information stored and brought back to primary memory for immediate use
Working Memory
• Not taken into account by modal model
• System allowing for temporary storage & manipulation of information required for various
cognitive activities
• Different from short-term memory
o Short-term does not account for ability to remember numbers at the same time as
reading a text, which we can do
o Short-term memory system able to carry out two tasks at once --introduced working
memory
• Working memory is system that connects all other memory systems together
o Can work with different types of information in dynamic fashion
o Baddeley & Hitch
• Made of 4 subsystems
o Central executive: coordinates information from 3 subsystems
• Controller
• Selects & integrates info across other subsystems
• Associated with consciousness; where solutions formulated
o Phonological loop: temporary store of linguistic information
• Anything auditory or language-related
• Obligatory access; must be processed and temporarily stored there
• Aka articulatory loop
• Helps in language acquisition --temporarily stored & rehearse words + sense of self
o Visuo-spatial sketchpad: Non-linguistic (visual) information
• Non-verbal
• Facilitate representation of things & their relations
• Planning route, putting parts together (assembly)
o Episodic buffer: moves information to & from long-term memory
• Both phonological loop & visuo-spatial sketchpad interact with long-term memory
• All subsystems have limited capacity and hold info only temporarily
• Fluid systems: cognitive processes that manipulate information
o Themselves unchanged by learning
• Crystallized systems: cognitive systems that accumulate long-term knowledge
• Example: count windows on house
o Imagine house with visuo-spatial sketchpad
o Count windows with phonological loop
o Central executive coordinates whole process
Working Memory & Brain
• Complex system
• Associated with dorsolateral prefrontal cortex (DLPFC) in frontal lobe
o Monitor/control alternative courses of action
o Important in selecting response in Stroop test
• Linked to function of central executive
Divisions of Long-Term Memory
• Two main divisions; declarative & non-declarative
• Declarative memory: contains knowledge that can be stated (I know that…)
o Explicit memory
o Factual information
• Divided into: (Tulving)
o Episodic memory: concerned with personal experience
• Personally experienced
• i.e. remember meeting this person
o Semantic memory: knowledge about words, concepts, their properties & interrelations
• General knowledge
• i.e. remember that July is after June
o Are not mutually exclusive --episodic memory can serve as gateway for formation of
semantic memory
• Remember experience around learning a fact
Neuropsychological Evidence Episodic-Semantic Division
• Patient with retrograde amnesia: inability recall events prior to injury
o After closed head injury
o Impaired episodic memory; important for personal identity
• But semantic memory intact
• Remembered which classes enrolled in, but do not remember attending
o Returned to normal within few weeks
• If semantic & episodic memory were truly independent, then damage to one should not affect
other system
o i.e. remember that personality is outgoing but don't remember instances of being
outgoing
Episodic & Semantic Memory Testing
• Technique to evaluate episodic memory
o Crovitz & Schiffman
