Chapter 05 - Memory Flashcards
three types of human memory
sensory, short-term, long-term
Sensory memory
Persistence of a stimulus
Sensory memory for vision
Duration of sensory memory can be lengthened by optimizing the stimulus- background /contrast.
Short Term Memory
Working memory, place to hold information temporarily.
External sources- By way of the perceptual process.
Internal sources- The result of reasoning, decision making, and problem solving.
Encoding
Information is encoded into a form that can be conveniently stored in human memory.
Some visual information is transferred into auditory form.
Capacity and Duration
Can hold about 6 units of information (Chunks)
People forget longer messages sooner-
The shorter the code the better.
Try to limit interference.
Rehearsing
Retains information in short-term memory.
Other activities should not interfere with the rehearsal process.
Divide longer strings of characters into groups of three or four to help rehearsal.
Ex. 217964831-> 217 964 831
Serial Position
Errors will tend to occur in certain character positions more than others.
7th Character
Auditory Stimuli – Last character tends to be recalled as well as the first character.
Visual Stimuli – Last character tends to be mistaken more often.
Conclusions for Designers
Don’t require users to retain
even a small amount of information for over 20 seconds, if rehearsal is not possible.
Long - term memory
Permanent memory storage. Relies heavily on organization. Learning, remembering, forgetting
forgotten information – lost access to it.
Belief
People do not lose information permanently. Hypnosis
Three operations take place related to remembering and forgetting
Encoding, storage, and retrieval.
Encoding
Process of deciding how to classify information. Sometimes only the essence of what was sensed will be encoded.
Ex. Good movie, lousy dinner, nice guy
Storage
Putting information into long-term memory.
Retrieval
Search in different locations when trying to remember something.
Try to recall how the information was originally filed.
Forgetting
May be due to a failure of any of these three operations.
E.G. original coding may be incorrect, info may be degraded during storage,
info may be difficult to retrieve
because searching is done in wrong place.
Interference
Proactive interference – material learned prior to the learning of new material may interfere with the use of the new material in a performance situation.
Retroactive interference
Exp. Learn task A, Learn task B, Perform A
Lotus 1-2-3, Excel,Lotus 1-2-3
Designers must find out what kind of responses have already been learned and then incorporate as much as possible the same kind of responses in the new system.
Recall Versus Recognition
Two commonly used ways of measuring remembered information.
Recalling info is much more difficult than recognizing info.
Designer should make full use of this fact.
Memory Skill
MNEMONICS – Conscious ways for helping to ensure the retention of material that would otherwise be forgotten.
Ex. String around your finger, complex visual imagery schemes
Cognitive performance aids- Require a person to either reduce or elaborate on information being received.
Reductions
Frequently take the from of acronyms:
Homes- Great Lakes
Roygbiv- Colors of spectrum
Ex. 9 times table, string around your finger
Disadvantage – Reduce the information so much
that it is no longer possible to reconstruct the original.
Elaboration
Adding information to make the material easier to remember.
Verbal Clues
By taking greater advantage of meaning that already exists in words, phrases, or concepts.
Every good boy does fine – lines of the Treble Clef.
Imagery Cues
A mental picture is created and viewed.
Man named S. memorized 50 numbers in 3 minutes.
Imagined a familiar street and he would place objects along the way.
Design Implications
Designers should not put an unreasonable demand on human memory.
Designers should develop interfaces that support an acceptable level of remembering.
Provide facilitators (training, instructions, performance aids) that make full use of the MNEMONIC concept.
