CPS613 – 2-6 1

ATKINSON-SHIFFRIN MULTI-STORE MEMORY MODEL

SENSORY = SENSORY REGISTERS  Definition:  Buffers for stimuli received through the senses  Sensory “trace” of the stimulus remains after it is gone.  They are constantly overwritten by new stimuli coming through channels  Types:  for visual stimuli: 0.5 seconds  for aural stimuli: about 4 seconds  Haptic memory for touch: longer

SHORT-TERM MEMORY =  Scratchpad for temporary of information  Can be accessed rapidly (around 70 ms)  Duration: decays rapidly: information stays there for about 30s to 5mns  Limited capacity  Information does not have to be in same modality as sensory input (e.g. visual information can be stored as auditory information) CPS613 – 2-6 MEMORY 2

LONG-TERM MEMORY = MAIN MEMORY  Definition: main memory used to store everything we know  Knowledge Stored:  Declarative Knowledge: (what) . factual knowledge concerning the nature of the world, in both its physical and its social aspects; it includes: o knowledge about what words, numbers, and other symbols mean; o knowledge about what attributes objects possess; what categories they belong to; o knowledge of events, and the contexts in which they take place. . Can be perception-based or meaning-based  Procedural Knowledge: (how) . rules and skills used to manipulate and transform declarative knowledge; . includes the rules of mathematical and logical operations; the rules of grammar, inference, and judgment; . includes strategies for and retrieving memories; . includes motor skills.  Properties  Huge capacity (limits not known)  Slow access time: 1/10 seconds  Little decay: long-term recall same after minutes, hours or days  Types of memory:  : memory of events and experiences in a serial form, including a description of the episodic context (time and place)  : context-free structured record of facts, concepts, and skills acquired  Information in semantic memory can be derived from episodic memory: we learn new facts from experience  Semantic Memory Structure:  Semantic Network (Collins and Quillian 1969)  Frames (Minsky 1974)  Scripts (Tomkins 1979)  Production systems

CPS613 – 2-6 MEMORY 3

INFORMATION FLOW:  Definition: concentration of the mind on one out of a number of competing stimuli or thoughts.  Attention is necessary to avoid stimulation overload.  Attention is  voluntary: it can be focused  involuntary: stronger stimuli can change focus  Attention is based on level of interest or need  Attention can be divided Rehearsal  Processes for retaining information in memory  All involve repetition of information  Maintenance Rehearsal:  to retain information in short-term memory  simple repetition of information  Elaborative Rehearsal:  to transfer information into long-term memory  repetition of information augmented with o related semantic information o unrelated semantic information () o sensory associations Retrieval  Recall: information reproduced from memory  Recognition: selection of information from given information  Recognition easier than recall  Decay is logarithmic: information lost very quickly and then more slowly  Retroactive Interference: new information causes loss of old information  Proactive inhibition: old information masks new