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Distributed Cognition. How a Cockpit Remembers Its Speeds Edwin Hutchins. Classical Cognitive Science. Thinking about thinking Mental processes Individual human agent How information is represented Transformed Combined Propagated Nature of knowledge. Distributed Cognition.
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Distributed Cognition How a Cockpit Remembers Its Speeds Edwin Hutchins
Classical Cognitive Science • Thinking about thinking • Mental processes • Individual human agent • How information is represented • Transformed • Combined • Propagated • Nature of knowledge
Distributed Cognition • Unit of analysis • Processes within system • Representations • External • Internal
Cognitive Systems • Organizations • Role of material media • Physical processes • Human actors • Material media • Interactions • Explicit nature of environment
Context: MD-80 Cockpit • Representations inside cockpit system • External to pilots • Procedure = behavioral properties • Constraint-based • Workers-finish-design
Task: Memory Task • Remembrance of speeds • For subsequent use • For proper & safe • Initial descent • Approach to land • Instrument landing
Actors: Pilot Roles Two pilots/stations • Complete dual-flight instrumentations • Pilot Flying (PF) • Pilot Not Flying (PNF)
Process Description • Prepare landing data (20 - 30 min. out) • Determine gross weight (Fuel Qty) • Find correct speed card (2000 lb. incr) • Post speed card • Set speed bugs on both ASIs • Descent - slow plane & configure wings • Final approach to land - Vref [Cross-checks & verbal communication]
Cognitive Description-External • How are speeds represented? • How are representations • Transformed, • Processed, • Coordinated? • How does the system’s memory work?
Observable Representations • Gross-weight display (Fuel Qty) • Speed card booklet • ASIs & speed bugs • Speed-select of Flight Director • Verbal exchanges between pilots • Setting bugs • Cross-checks • Call-outs /progress reports
Additional Representations Memory of each pilot • Individual considered as part of system Media in the cockpit • Task environment forms memory • Internal representations
Speed Card & Gross Weight • Long-term memory • Gross weight • Appropriate speeds • Functionally durable • Filtered information Correct weight = correct speeds • Distributed access • Social space • Knowledge
Distribution & Transformation • Transformations of representations • Verbal (as relayed between PNF & PF) • Via speed bug settings • Cross-checking & redundancy • Time-critical procedure indications
Configuration Changes • Speed determined • ATC instruction • Position in approach • ASI needle nears appropriate bug • PF calls for flap/slat configuration • PNF configures flaps/slats • Verification & cross-checks (with speed card)
Salmon Speed Bug • Final approach speed reference (Vref) • Spatial relation with ASI needle • PF to track speed • PNF to determine deviations • Verbal representation of call-outs Lightens demand on visual load of PF
External Representations Summary • Speed bugs • Resource for later processes • Durable working memory • Coordinated representations • Verbal • Speed card/fuel qty • Configurations • “System memory”
Cognitive Description-Internal • Cognitive tasks of pilots • Task specification • Not procedural recount • Provide constraints on useable • Representations • Processes • Interpretation not recall Function in system memory
Speed Card & Gross Weight • Pattern matching • Implicit learning • Internal structure for prediction • Interpret values • Card design • Working memory • Setting bugs - varied sequences
Configuration Change Bugs • Numerical relations • Spatial position • Space of speeds “Configuration zones” • Superimposing representations • Functional systems
Salmon Speed Bug • Numerical relation • Scale of ASI and need positioning • Spatial proximity • Scale-reading task • Base of salmon bug • Verbal call-out - aural cue
Notion of Memory • Traditionally a psychological function • A series of tasks in a functional system • Recognition & recall • Pattern matching • Cross-modal transformations • Distributed • Among human agents • Between human agents • Transformed external representations
Workers Finish the Design • Provides constraints and artifacts • Salmon bug • Engineer’s design • Ease of location • Ease of interpolation • Pilot’s use • Determine 5-kt. deviations • Not anticipated by designer (engineer)
Cockpit as Cognitive System • Unit of analysis • Transforms & propagates information • Use of representations • Notion of memory task • Redundant & robust