Conscious and Automatic Processing Have been considering how people process information We see that it is often dependent on context expectation and experience Another important aspect of human information processing to consider for interactive design is automatic processing conscious processing
Expertise through automatic processing design objective is to be make user interface ‘transparent’ to the user automatic processing results when knowledge and actions can be compiled into a single internal ‘procedure’ comes with decreasing reliance on feedback or confirmation of actions by the system can you think of a skill you have acquired where this has occurred?
Design requirements If a sequence of low level actions are to be carried out automatically, then all the necessary actions need to be executed without waiting for any intermediate action by system. Learning a sequence of actions will be helped if these are meaningful in some way to the user What other design implications which must be considered when developing new interactive systems due to users performing some actions automatically?
Memory early theories postulated two separate types - long term and short term short term memory was demonstrated to have finite capacity (7 +/- 2 ‘chunks’ of information) finite duration (decays even after 2 or 3 seconds) volatile (easily overwritten by by new information) capacity could be increased by ‘pattern building’ or encoding current theory shows memory as a hierarchical model
Short term or Working Memory limited number of items that can be held in an active state at any one time Need time to get information from sensory memory into working memory Need even more time to get items stored in working memory to be stored permantly Can overload working memory
Design Implications support user by reducing demands on working memory do not require user to remember temporary operating states and labels help the user remember how far the current task has progressed help the user remember what the system expects them to do next leads to the important principle of visibility of current state and feedback about current action Think how menus can alleviate memory limitations
Guiding Users Attention at the interface Since we know users can be distracted involuntarily we need to consider how we can Get their attention again Get them to focus on what they should be looking at Cognitive psychology provides a number of techniques which can be used reduce search time by structuring layout so user perceives meaningful components in information highlighting through dividers, windows, colour to emphasise structure alerting user to new or important information (look at me) using flashing, inverse video, auditory warnings
Guiding Users Attention at the interface By Location location of information on screen guided by its relative importance important requiring immediate attention - prominent less important - less prominent but in a consistent location much less important - not presented but available on request