U SER I NTERFACE L ABORATORY Situation Awareness a state of knowledge, from the processes used to achieve that state (situation assessment) not encompass all of a person’s knowledge but only that portion pertaining to the state of a dynamic environment explicitly recognized as a construct separate from decision making and performance separated from others that may influence it – attention, working memory, workload, and stress knowing what is going on The perception of the elements in the environment within a volume of time and space (Level 1 SA), the comprehension of their meaning (Level 2 SA), and the projection of their status in the near future (Level 3 SA) Automaticity can occur without attention Benefit SA for overcoming limited attention capacity Logan (1988) – through a direct-access, single-step retrieval of actions to be performed from memory Level 1 Sa  script from memory Major implications (a)Good performance with minimal attention allocation (b)Significant difficulty in accurately reporting on the internal model and related key environmental features (c)Unreliability and inaccuracy of reporting on processes after the fact

U SER I NTERFACE L ABORATORY Situation Awareness Preattentive processing spatial proximity, color, simple shapes, or movement, providing cues for further focalized attention to achieve perception cue salience Attention Major limit on SA direct attention for not only perceiving & processing the cues attended to but also the later stages of DM & response execution information sampling to avoid limited attentional capacity – in rapid sequence following a pattern from LTM, WM to modify attention deployment multiple resource theory automaticity Perception preconception or expectations – speed & accuracy of the perception LTM – classifying perceived info into known categories or mental representations in the perception process (Level 1 SA) Working Memory Level 2 & 3 SA occur in WM main bottleneck for SA LTM Schemata coherent framework for understanding info, encompassing highly complex system components, states, & functioning Much of the details of situations are lost but the info became more coherent & organized for storage, retrieval, and further processing Script – a special type of schemata – sequences of appropriate actions for different types of task performance ◦Produce single-step retrieval of actions from memory Mental Model Rouse & Morris (1985) – Generate descriptions of system purpose & form, explanations of system functioning & observed system states, & prediction of future states ◦experts will develop MM in a shift from representational to abstract codes ◦Complex schemata to model the behavior of systems VanDijk & Kintsch (1983), Roschelle & Greeno (1987) ◦Situational model (situation model, situation awareness) as a schema depicting the current state of the system model ◦ well-developed mental model provides (a) Knowledge of the relevant elements in directing attention and classifying info in the perception process (b) A means of integrating the elements to form an understanding of their meaning (Level 2 SA) (c) A mechanism for projecting future states

U SER I NTERFACE L ABORATORY Situation Awareness Goals SA is fundamentally linked with a person’s goals The basis for most decision making in dynamic environment Top-down decision process goals & plans direct which aspects of the environment are attended to in the develop of SA bottom-up processing Salient cues will activate appropriate actions & plans related to the role of mental models and schemata

U SER I NTERFACE L ABORATORY Situation Awareness Stress physical stressors social psychological stressors Cognitive tunnel vision premature closure decrement in WM capacity and retrieval Workload 1. Low SA with low workload – little idea of what’s going on 2. Low SA with high workload – erroneous or incomplete perception & integration of info 3. High SA with low workload – easy to process (an idle state) 4. High SA with high workload – working hard but successful in achieving an accurate and complete picture of the situation Complexity Automation Automation fails when (a)A loss of vigilance and increase in complacency (b)A shift from an active info processor to a passive info recipient (c)A lot of or change in the type of feedback provided to operators System Design the degree to which the system acquires the needed info from the environment display interface for producing that info to the operator Interface Design mental workload, level of SA provided 1. displays provide info that is processed and integrated in terms of level 2 & 3 SA 2. Info is presented in terms of operator’s major goals 3. Critical cues for activity schemata & MM to be determined and made salient 4. Both top-down and bottom-up processing 5. Global SA 6. Filtering out extraneous info & reduction of data 7. system-generated support for projecting future events & states 8. System designs that support parallel processing Errors in SA incomplete SA – knowledge of only some of the elements inaccurate SA – erroneous knowledge concerning the value of some elements Level 1 SA simply fail to perceive certain info 1. From a lack of detectability or discriminability for the signal 2. From a failure of the system design to make the info available to the operator human limitations in sampling, attention, and attention sharing attentional narrowing Level 2 SA misreading of cues No mental models wrong MM based on a subset of cues because of representativeness and availabillity biases No model exists at all – Level 2 SA in WM Level 3 SA No highly developed mental model