Cognition and Related Ergonomical Analysis of an Air Traffic Controller's job.

1. Cognition
conscious mental activities : the activities of
thinking, understanding, learning, and
remembering
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Findings in cognitive science confirm that there is a close connection between
thought processes, perception, and physical and social actions .
The implication of this for the design of interactive systems is that attention must
be paid to human physical and cognitive abilities, and the context and social
environment in which they are applied (Dourish 2001).
Findings in cognitive psychology, multimodal interaction, and tangible and social
computing are subsumed under a new paradigm termed reality-based interaction
(Jacob et al. 2008).
This paradigm proposes that human-computer interaction should be based on the
real world, so as to utilize human characteristics and modes of behavior as
acquired by experience and determined by evolution
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2. Cognitive Issues
Equipment
Equipment design is a frequent source of threats for ATC. Malfunctions and
design compromises are among the conditions that controllers have to
manage to varying degrees during everyday operations
Workplace factors
This category of threats comprises items such as glare, reflections, room
temperature, non-adjustable chairs, background noise, and so forth.
A controller's work is more difficult if there are reflections from the room
lighting on the screens.
A tower controller may have problems visually acquiring traffic at night if
there are reflections from the interior lighting in the windows of the tower.
A high background noise level (i.e. from fans necessary to cool the
equipment) may make it more difficult to accurately understand incoming
radio transmissions. Similarly it may make outgoing transmissions harder to
understand for the receiving parties.

3. Cognitive Issues
Weather
Weather is perhaps the most common category of threats
to all aspects of aviation, including ATC operations.
Managing this threat is made easier by knowing the
current weather and the forecast trend for at least the
duration of a controller's shift.
For example: changes in wind direction may involve
runway changes. The busier the traffic, the more crucial
becomes the timing for a runway change. A controller will
plan strategies to make the change with minimal
disruption to the traffic

4. COGNITIVE MODEL OF THE
CONTROLLER'S TASK

6. External Events
• External events that call for controller actions occur primarily in the
airspace outside the tower or en route center.
• These include the filing of flight plans, pilot requests for
clearance, changes in aircraft trajectories, handoffs from other
controllers, and changes in weather.
• Other important events, however, may occasionally occur at an airport or
in an air traffic control facility itself, such as blocked runways and
instrument or power failures.
• The immediate manifestation of most of these events is the presentation
of new information to the controller.
• The information presentations that are spawned by the events are easily
identified and categorized through task analysis. These categories include
visual changes on the primary radar display, information contained on the
flight strips, auditory input from voice communications by pilots and other
controllers, visual and auditory alerts provided by automated handoffs or
by projected or real loss of separation, as well as other input regarding
weather conditions and runway status.

7. Working Memory
• Once information is perceived, it may be retained in working memory.
• The human working memory system represents the ''workbench" at which
most of the conscious cognitive activity takes place (Baddeley, 1986).
• Working memory may temporarily retain information that is either verbal
or spatial.
• Verbal working memory is the "rehearsable" memory for sounds, typically
digits and words, and is the memory system that the controller uses when
receiving a request or readback from the pilot (Morrow et al., 1993).
• Hence, working memory represents a critical component of
communications. It is also the mechanism used when the controller, after
reading a data block or flight strip, must temporarily retain the written
information prior to translating it into a spatial representation.

8. Long-Term Memory
• The processes involved in comprehending the perceived information draw
heavily on knowledge structures in long-term memory.
• Characterizing less dynamic aspects of the controller's environment, such
structures include knowledge of the airspace, including
geography, terrain, air routes, fixes, and air traffic control sector shapes
around a particular facility (Redding et al., 1992), knowledge of radar and
equipment characteristics and capabilities, knowledge of weather
configurations, and knowledge of different aircraft performance and
maneuvering capabilities.
• Experience in a domain often leads to long-term memory structures that
permit more efficient and/or insightful encodings or "chunking" of
multiple events (Chi et al., 1981). In the air traffic control domain, for
example, experienced controllers may directly identify important types of
events involving multiple aircraft (such as conflict) rather than focusing on
individual aircraft
• The decision-making and planning processes also draw heavily on
knowledge in long-term memory.

9. COGNITIVE VULNERABILITIES IN THE
CONTROLLER'S TASK

10. • The cognitive task analysis has revealed a diverse array of cognitive
skills that the controller must marshall to handle the complex
dynamic problems of managing multiple aircraft in an uncertain
environment.
• For some of these skills, the human expert is uniquely qualified and
so far has well exceeded the capabilities of even the most
sophisticated forms of artificial intelligence.
• In the most general terms, we can characterize these strengths in
terms of the controller's adaptability and flexibility in carrying out
knowledge-based behavior.
• Although most control involves fairly routine following of
procedures, the skilled controller is keenly attuned to subtle cues
that may predict future unusual events and will possess in longterm memory a wide variety of adaptive strategies and plans to
address these events if they do occur

11. Visual Sampling and Selective
Attention
• Because much of human visual search and pattern recognition is
serial, with event-filled displays the controller is vulnerable to
missing critical events through breakdowns in the serial visual
scanning process (Stein, 1993).
• This is particularly true to the extent that many of these events
must be inferred from signals that are not particularly salient to the
untrained eye (e.g., a future conflict, a change in the altitude field in
the data, a pilot's failure to implement a requested course
alteration) rather than perceived from salient ones (e.g., a blinking
data tag or automated alert for loss of separation).
• The quality of visual sampling is further inhibited by the amount of
information or clutter in the visual environment, whether this is the
view of a radar scope or the view from the tower of a busy taxi and
ramp area.

12. Expectation-Driven Processing
• Expectations influence perceptions.
• We see (or hear) what we expect to perceive, and
this tendency allows the perception of expected
and routine events to proceed rapidly and with
minimal effort.
• Yet such expectation can be a source of
vulnerability when events occur that are not
expected, especially when these events are not
perceptually salient or occur under conditions of
high workload.

13. Working Memory
• Working memory is very susceptible to
interference, both from other items
competing for the same processes and from
other information-processing activities.
Speaking, for example, will disrupt verbal
working memory, and visual scanning and
search will disrupt spatial working memory

14. Long-Term Memory
• long-term memory is also relevant for maintaining
situation awareness. Vulnerabilities in long-term
memory are manifest in four kinds of activities.
• First, there may be breakdowns in what we call
"transient knowledge" in long-term memory, which
consists of immediate memory for events in the
current situation and prospective memory for actions
that the controller plans to perform within the next
few minutes.
• These lapses or breakdowns occur when controllers fail
to recall developing aspects of the current situation of
which they were at one time aware.

15. Psychosocial factors

16. Psychosocial factors at work refer to interactions
between and among work environment, job
content, organisational conditions and workers'
capacities, needs, culture, personal extra-job
considerations that may, through perceptions
and experience, influence health, work
performance and job satisfaction.

17. Psychosocial work environment

18. Psychosocial factors
Social support is a crucial point in stress management.
According to the Karasek and Johnson model, this is one of
the three factors that concur in determining stress conditions.
It can be seen in two main aspects:
(a) the availability of social services aimed at satisfying ATCs’
needs. They concern, for example, transport facilities for
reducing commuting times, canteen and sleep facilities, and
housing conditions;
(b) the recognition at a social level of the importance of ATCs’
activities and, consequently, its appreciation by the general
population. ATCs complain that the general public do not fully
understand the complexity and importance of their job, which
is often considered “second class”.

19. • Excerpt :
Michel, after an enquiry on job satisfaction within a group
of Swiss controllers, pointed out that “the controllers’
descriptions of their own profession are very emphatic:
ultra specialized, honourable, indispensable,
irreplaceable, unique ... There is a shortage of
descriptions to prove that this profession is unlike the
others, and that it is one to be carried out with pride. This
internal acknowledgement makes up for a lack of external
image: the profession is little known among the general
public, and is even often blamed for causing continuous
traffic delays

20. REFERENCES
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Flight to the Future: Human Factors in Air Traffic Control ( 1997 )
Human Factors and Ergonomics
José J. Cañas, Boris B. Velichkovsky and Boris M. Velichkovsky
University of Granada, Spain
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Occupational stress and stress preventionin air traffic control
Professor Giovanni Costa
Institute of Occupational Medicine
University of Verona
PSYCHOSOCIAL FACTORS AT WORK:
Recognition and control
Report of the Joint ILO/WHO Committee
on Occupational Health
Ninth Session
Geneva, 18-24 September 1984
ORGANIZATIONAL PSYCHOLOGY AND SAFETY CULTURE IN AIR TRAFFIC CONTR
MARCUS ARVIDSSONOL
Department of Psychology
Work & Organizational Psychology Division
Lund University
2006