G063 - HCI Design

Perception, Attention, Memory & Learning

(PALM)

Learning Objectives:At the end of this topic you should be able to:

• indicate how perception, attention, memory, and learning affect HCI design choices

HCI Design Factors

In trying to design an HCI which:• is easy to learn• is easy to remember• reduces user error

Factors to be considered will be:• Perception• Attention• Memory• Learning

Perception• is the input from sight and sound (& touch?)

• user will have preconceived ideas :– colours: green for go, red for stop– sound: certain sounds are perceived as happy or sad– touch: key ‘click’ when pressed haptic feedback

• need to take preconceived ideas into account:match = user thinks they can use the systemmatch = user may think they can’t use the system

Attention• a user may have a limited attention span;

So, to maintain attention:• use consistent & logical layout

– grouping of similar items - logical menu structure

– familiar data entry - top to bottom, left to right

– consistency - buttons & menus in the same place (on all screens/web pages)

– consistent use of colour

• uncluttered screen layout:– too much information disinterested user (short attention span)

• clear labels used, salient points obvious

• to gain attention use:– flashing text, pop-up messages, sounds, …..

Memory• long-term, short-term & physical memories used

• an interface may be used infrequently– so can’t rely on user remembering how to use system need to use links to pre-existing knowledge

• i.e. use user’s mental model

physical & short term memory will be involved – designer must ensure short term memory is used

• ‘keep it simple and recognisable’

To aid memory:• screen layouts should be consistent & uncluttered• use of colour should be consistent and sensible• design should link to pre-existing knowledge

Learning

• user may not use the system often• user may not have received training

system must be intuitive

Try to use:• uncluttered screen layout• group items on screen

– so layout matches way user works

• simplistic language • on-screen help