Question 1 of 14: Human Information Processing — Memory and Attention

Question 1: Human Information Processing — Memory and Attention (10 marks)

Question text not reproduced: the examination questions are © Engineers and Geoscientists BC. Open the official past paper (linked at the top of this page) to read the question, then follow the worked solution below.

Part A — short-term/working memory and long-term memory. Short-term (working) memory is the limited-capacity, limited-duration store that holds information a person is actively using right now — classically bounded to about 7±2 chunks (Miller) and decaying within roughly 15–30 seconds unless rehearsed. It is where a user holds a phone number just read from a screen, or the steps of a task they are midway through. Long-term memory is the effectively unlimited-capacity, durable store for knowledge, skills and experience built up over a lifetime, encoded through rehearsal and meaningful association and retrieved by recognition or recall. Two UI design implications: (1) Minimize working-memory load — keep task-relevant information visible on screen (e.g. show the drug name and dose being programmed throughout a multi-step entry) rather than requiring the user to remember a value from an earlier screen; this matters because working memory is the most fragile link in the chain, and interruption (a phone ringing, an alarm sounding on an adjacent pump) can wipe it entirely, which is especially risky in a clinical setting. (2) Favor recognition over recall (e.g. selectable lists of drugs from the library instead of free-text entry of a drug name) because recognition draws on long-term memory's associative strength while recall depends on the much weaker, more effortful reconstruction of information that is not currently displayed — this reduces both cognitive effort and the chance of a transcription error.

Part B — attention. Attention is the cognitive process of selectively concentrating on one part of the environment or one task while filtering out competing stimuli; it acts as the gate that determines what information from the environment is admitted for further processing (perception, working memory, decision-making) and what is ignored. In human information processing it is the resource-limited bottleneck between perception and memory — because a person can only attend fully to a small number of things at once, attention determines which of the many available stimuli actually get processed and acted on. Two UI implications: (1) Use visual salience to direct attention to what matters — e.g. displaying the programmed drug, dose and rate in a large, high-contrast confirmation panel before infusion starts, and using colour/motion sparingly so a genuine alert is not lost among routine display elements; this is important because in a high-workload clinical environment attention is a scarce resource, and a design that competes for attention with irrelevant detail increases the chance a critical value is never actually seen. (2) Avoid demanding divided attention during safety-critical entry — do not require the nurse to attend to two spatially separated displays simultaneously (e.g. the pump screen and a paper drug-library reference) while programming a rate; this matters because divided attention degrades performance on both tasks and is a well-documented source of data-entry error in infusion-pump programming.