Cognition:
Memory
CS352
Cognition
• What goes on in our heads when we carry
out activities (eg, use UIs)?
• Book:
– attention, perception, memory, learning,
speaking/reading/listening, problemsolving/reasoning
Memory
• Number activity:
347 901 331 7347 89
Memory (cont)
• Chunking
• UIs use this.
Memory (Cont.)
• Number activity:
134 790 133 1734 789
Memory (Cont.)
• Number activity:
134 790 133 1734 789
347 901 331 7347 89
Memory (cont)
• UI implications from these two activities?
Structure of memory
• Short term memory (STM)
– Demonstration.
• Long term memory (LTM)
– Everything else.
– Mostly when we say “memory”, we mean
LTM.
Recognition and Recall
• Money activity #1
• GUI strength: emphasize recognition over
recall.
– But usually slowed down by need for visual
scan in GUIs.
– UI solutions.
People storing/retrieving knowledge
• Declarative knowledge
– NYC is north of Miami.
– To get key out of ignition, car must be in “park”.
– Easy to teach.
• Procedural knowledge
– How to spin a basketball on 1 finger.
– How to boot a smart phone into recovery mode.
– Best taught by demo, learned by practice.
Encoding and (lack of) precision
• How we encode affects:
– what we retrieve (recall or recognize) and
– how we retrieve
• Money activity #2 (if time permits)
Ways to encode
(and constraints)
• Appearance attributes, sound, rhythm,
rhyme.
• Traveling performers: how did they do
that?
– Thru encoding tied to constraints. (Storage for
retrieval).
• Rhythm
• Rhymes with
• Must make sense
Encoding (cont.)
• Retrieval
– Word guessing activities
• So, reduce and/or facilitate encoding:
– Constraints reduce encoding needed.
– Support external cognition (stay tuned) to
remove need to encode.
• eg: Excel’s arrows make dependencies explicit.
– Provide users a variety of ways to encode
(eg, color, flagging, position).
• eg: forgot filename, but it’s the red folder.
Case study
• The Microsoft Office (past) rearranging of
menus due to recency.
– Think about chunking/grouping
– Think about imprecision of encoding.
– What will do if don’t see what you want?
• Does this mean “most recent” is always a
bad idea in a UI?
Encoding (cont.)
• Different amount of encoding needed for:
– Remembering a bunch of arbitrary things.
– Remembering things with meaningful
relationships.
• Hotel is on north side of town.
– “Remembering” things that can be derived.
• Tied to “mental models” (stay tuned).
Implications for your Project
• How can UI help user remember
(store/retrieve) here?
– Think about: recog/recall, practice, chunking,
declarative vs. procedural, encoding, constraints
• Ideas:
– Grocery system content eg: what brand was that
that I bought last time?
– Grocery system UI mechanism eg: how do I get
a subtotal?
– Discussion: Your project examples?