Human Capabilities: Attention CS352

Announcements 1. Choice for next Wednesday (Week 9). 2. Team presentations on Monday of Week 10. 3. Last 5 minutes of today’s class.

Attention Selecting what to focus on, at a point in time, from the range of possibilities. Banner ads steal attention “pre-brain”. Attention also happens in brain. We focus on what we think is relevant to our task. Attention highly dependent on our limited short term memory (which is small). HOWEVER -- if didn’t make it thru senses, not a contender. 👁

Brain attention Can brain multi-task? Then ...? No. Mostly attend to one thing at once. Then ...? Like in operating systems: Interrupt system, context switch. Cost of context switch. Missed triggers. Thus, UIs should encourage this with care. Hands-free cells while driving? Emails while in talks/meetings/classes? Flow? Depth of concentration?

What do people (usually) attend to? 📝 The task, not the tool. Ex1: The words you’re writing, not the pencil. Ex2: The story in the book, not the physical book. If have to attend to the tool, might forget ... Ex1: Pencil gets too dull, attend to pencil (sharpen).  Have system (last few words you wrote) show where you left off. External cognition saves the day! Ex2: Doorbell rings, put down book; where was I?  Let user mark where you left off. (eg, bookmark).

Implications People won’t pay much attention to a UI. Very surface-level attention. Want to do tasks familiar way (remember Abby?) UI should allow focus on task, not UI. “Don’t make me think!” (about the UI) Pay a bill Transfer $ to savings Pay dentist via fund transfer Change PIN Open new acct Buy travelers checks This is Fig 8.3, p. 100, Johnson book. The list of tasks is about: which widget to you push to do these things.

Demanding Brain’s Attention: Interruptions When COMPUTER decides to call attention to something. Four important kinds: Immediate For when MUST pay immediate attention. Mediated Computer decides when to interrupt. Scheduled Negotiaated Best for productivity AND learning.

Attention Take-aways (Basics for UIs) Users can’t attend to everything at once. If info does not make it thru senses, brain can’t attend to it. Once in brain: users attend to what seems most relevant. (Remember Info Foraging Theory?) User has the right to their own attention. There is a cost to making them attend to UI. Do not impose it arbitrarily.