CH9

Question 1

Mental workload:

Answer 1

the information
processing demands imposed by the performance of cognitive tasks. Workload depends on
the match between task requirements and capacities, and different people have different
capacities.

Question 2

Effort:

Answer 2

conscious exertion

Question 3

Arousal:

Answer 3

physiological sense of readiness for activity.

Question 4

Resources:

Answer 4

hypothetical processing reserves or sensory, motor, or information processing capacities.
Sometimes these concepts are interrelated. Too much or too little workload impairs
performance, so a balance needs to be found.

Question 5

Kahneman: the arousal of an individual

determines

Answer 5

the capacity available to engage in different activities.

Question 6

An indicator of stress is

strategy adjustment:

Answer 6

when demands are high, we switch to using less effortful strategies for
performing a task. An example is attentional narrowing: you restrict your attention to an
inappropriately small set of displays or information sources. Fatigue after-effects: after a
fatiguing task, people show a preference for using low-cost strategies for performing other,
unrelated tasks.

Question 7

attentional narrowing:

Answer 7

you restrict your attention to an

inappropriately small set of displays or information sources.

Question 8

Fatigue after-effects:

Answer 8

after a
fatiguing task, people show a preference for using low-cost strategies for performing other,
unrelated tasks.

Question 9

Difficulty intensitivity is

Answer 9

that allocating more resources to one of two tasks

does not always hurt performance on the other one.

Question 10

Structural alteration is

Answer 10

changing the

structure of a task without changing its difficulty.

Question 11

Perfect time-sharing is

Answer 11

when two tasks
shown to interfere with other tasks can nonetheless be performed together without
decrement.

Question 12

multiple-resources concept (MRC)

Answer 12

(different sorts of tasks draw on separate resources)

Difficulty intensitivity is that allocating more resources to one of two tasks
does not always hurt performance on the other one.

Structural alteration is changing the
structure of a task without changing its difficulty.

Perfect time-sharing is when two tasks
shown to interfere with other tasks can nonetheless be performed together without
decrement.

These three are all evidence for the multiple-resources concept. The MRC is
inadequate as a model of attention but it can serve as a useful framework for predicting
operator performance.

Question 13

Strategy shifts can be used as

Answer 13

an indicator of
changes in operator mental workload. The skill level of the performer has a large influence
on the methods or strategies employed.

indicator of changes in
operator mental workload. Large influence of skill level and processing resource demands.

Question 14

Three classes of techniques have been developed to measure mental workload:

Answer 14

physiological, performance-based, and subjective measures.

Question 15

Physiological measures of mental workload are

Answer 15

direct measurements of various body
or brain responses to task performance. You can either measure general arousal, or
specific brain activity.

Underlying assumption: various bodily systems are activated whenever the demand for mental effort increases. Pupil diameter (pupillometry) and
heart-rate variability are the most suited for examining changes in mental workload.

Event-related potentials have been shown to be effective indicators of mental load,
and can also show which of two tasks is seen as more important. ERPs give an
indication of more specific processing activity. The P3 is linked to workload and it has
a big amplitude when an unexpected stimulus occurs. Measuring the amplitude of
ERP components may be a good indicator of workload even when the event used to
elicit the ERP is totally irrelevant to the task.

Question 16

Primary-task technique:

Answer 16

simply measuring some aspects of task performance. When
difficulty is below a certain level, primary-task performance will not show any
decrements. This is why it’s better to use a secondary-task methodology, in which a
second task is performed at the same time as the primary task, and the extent to
which performance on one of the tasks suffers is measured. The purpose is to use up
any capacity that might be available so that changes in the difficulty of the primary
task will be reflected in performance changes. In a loading-task paradigm, the focus
is placed on the secondary task, and different aspects of primary-task performance
are measured. In a subsidiary-task paradigm, the emphasis is placed on the primary
task, and performance on the secondary task is measured. Embedded secondary
tasks are tasks that can occur naturally in the task environment under consideration,
but are not part of the primary-task performance

Question 17

secondary-task methodology

Answer 17

a second task is performed at the same time as the primary task, and the extent to
which performance on one of the tasks suffers is measured.

Question 18

In a loading-task paradigm, the focus

is

Answer 18

placed on the secondary task, and different aspects of primary-task performance
are measured.

Question 19

In a subsidiary-task paradigm, the emphasis is placed on

Answer 19

the primary

task, and performance on the secondary task is measured.

Question 20

Embedded secondary

tasks are

Answer 20

tasks that can occur naturally in the task environment under consideration,
but are not part of the primary-task performance

Question 21

Performance operating characteristics:

Answer 21

performance on one task is plotted against
performance on a second task. The more difficult a task, the harder it will be to
combine with a second task and the more performance will suffer to the extent that
resources are withdrawn from it and allocated to the other task. Performance at
different allocation policies (e.g. devote 50% to task A and 50% to task B) will fall
along a curve, the POC.

Question 22

Subjective measures, in which people report how much workload they experience,

Answer 22

are based on judgements and they’re influenced by the range and frequency of
different possible stimuli. Ratings of a task with a relatively restricted range of
difficulty conditions will tend to overestimate workload whereas a high range of task
difficulties will result in an underestimation of task workload. This can be solved by
showing all possible conditions in a practice session. Some researchers have
proposed that unidimensional methods are just as appropriate as multidimensional
method. Dual-task performance is determined by a number of factors, including the
resources invested in the task and competition for common resources.

Question 23

A workload measure must be

Answer 23

reliable, easy to use, and sensitive.

Question 24

A measure is diagnostic if

Answer 24

it not only reflects changes in load, but also discriminates between the amounts of load
imposed on various operator capacities or resources, such as perceptual versus memory
load.

Question 25

Intrusiveness refers to

Answer 25

any disruption in performance of the task as a result of the application of the mental workload measurement technique.

Question 26

N1

Answer 26

selective attention

Question 27

N2

Answer 27

target detection

Question 28

P2

Answer 28

early processing

Question 29

P3

Answer 29

memory updating

Question 30

Situation awareness

Answer 30

= the perception of the elements in the environment within a volume of time and space, the
comprehension of their meaning, and the projection of their status in the near future. It’s
supported by attention, working memory, and long-term memory.

Question 31

Cognitive factors in situation awareness:

Answer 31

how and where attention is directed will determine which elements in the environment are incorporated into the situation
awareness, and both the salience of information and the individual’s goals and
priorities in directing attention will influence perception and performance. Memory is
important because situation awareness involves keeping track of events and objects
in the environment. Only information that people pay attention to and are aware of
influences their situation awareness. There is a direct link between situation
awareness and working memory, and SA gets worse when WM resources are
overtaxed.Long-term memory is also important, as you can depend on that and thus
free up working memory resources for other task.

Question 32

Situation awareness and mental workload are

Answer 32

independent constructs

Question 33

To measure situation awareness,

Answer 33

there’s the same criteria applied to mental workload

measurement. It’s most commonly been assessed with self-report questionnaires.

Question 34

crosstraining

Answer 34

in this, team members receive information and training in the tasks of
other team members. Teams that must function in high-workload environments may
benefit from training to recognise high-stress conditions and to adapt their behaviour
accordingly.

Question 35

Primary-task technique:

Answer 35

measure some aspect(s) of task performance.

Question 36

Secondary-task

methodology:

Answer 36

extent to which performance on one of the tasks suffers is measured

Question 37

Probe-reaction-time task:

Answer 37

whether two letters were same/different. RT longest when probe (respond
to tone with key press) is presented around time that the second letter is presented. Probe-reaction
time depends on nature of the task.

Question 38

Loading-task paradigm

Answer 38

emphasis on second task, different

aspects of primary task performance are measured.

Question 39

Subsidiary-task paradigm

Answer 39

emphasis on primary

task, performance on second task measured.

Question 40

Embedded secondary tasks:

Answer 40

occur naturally in task
environment, not part of primary-task performance. Important that tasks overlap on their required
information resources.

Question 41

motor programs

Answer 41

(functional state
that allows particular movements to occur): actions that can be performed in an open-loop
manner, so without feedback. Actions under conscious control are said to be performed in a
closed-loop manner. Slips of action are most likely to occur during the automatic execution of
routine actions, they’re like failures of attention that happen because the wrong action plan is
maintained or because attention is switched to the wrong elements of a plan or aspects of
the environment

Question 42

Initiating and maintaining actions plans:

Answer 42

Norman has this theory that actions are
based on schemas that embody the procedural knowledge needed for carrying out
an act. Schemas are generalised procedures for carrying out actions. His activation-
trigger-schema (ATS) system assumes that actions are governed by high-level
parent schemas. When the parent schema is activated, the child schemas that
control component parts of the action are initiated automatically. He proposes two
systems that influence schema activation, a contention-scheduling system and a
supervisory attentional system. Contention scheduling is a passive process that
emerges naturally as a result of the way schemas are learned and performed. It can
directly activate and order action schemas that are linked to each other with both
inhibitory and excitatory connections.

Question 43

Schemas are

Answer 43

generalised procedures for carrying out actions.

Question 44

activation-

trigger-schema (ATS) system

Answer 44

assumes that actions are governed by high-level

parent schemas.

Question 45

Contention scheduling is

Answer 45

a passive process that
emerges naturally as a result of the way schemas are learned and performed. It can
directly activate and order action schemas that are linked to each other with both
inhibitory and excitatory connections.

Question 46

The supervisory attentional system

Answer 46

Whenever no schema exists for performing an
action, a higher level of control is needed. This is provided by the SAS that can
directly activate or inhibit schemas but cannot select them directly. Without the SAS,
attention is withdrawn from goals or actions, and the relevant schemas may suffer
from lack of activation.

• If the SAS is not intact or not functioning properly, two disorders may result: either increased perseveration or disorganised behaviour.

Top-down control by supervisory attentional system (SAS), for less familiar actions.

Question 47

Performance operating characteristic (POC)

Answer 47

extent to which two tasks can be performed together.

Question 48

Allocation policies:

Answer 48

how much % allocated to either task, POC curve. its first necessary to measure
single task performance for both tasks, that counts as 100%