Attention

1
Attention Human Decision Making

• Decision Making is the end goal of Human
  Information Processing.
• However, people are not optimal decision
  makers, due to inattention, personal
  biases,
• and errors in judgment.

2
Types of Human Attention

• Selective Attention
• Focused Attention
• Divided Attention
• Sustained Attention

3
Selective Attention

• Selective Attention Requires monitoring of
  several channels of information to perform a
  single task.
• Examples Pilot Nuclear power operator
  Receptionist

4
Selective Attention Stressors

• Load Stress - Too much information at once
  Examples Two simultaneous talkers
  Improperly trained workers
• Speed Stress - Information presented too quickly
  Examples Dials changing too quickly to
  comprehend
• ATC instructions transmitted too rapidly

5
Selective Attention Guidelines

• Decrease number of channels, may increase
  signal rate.
• Decrease stresses, allow more channels to be
  monitored.
• Place channels closer together.
• Train workers to be effective workers.

6
Focused Attention

• A person must attend to one source of
  information and ignore all other sources.
  Examples Conversations in noisy
  environment Distracting audience side
  conversations

7
Focused Attention Guidelines

• Make channels distinct
• Separate channels
• Reduce competing channels
• Make channel of interest more distinct

8
Divided Attention

• Limited capacity to process information.
• Required to do more than one task at a time,
  also called time sharing.
• Two theories regarding information processing
  Single-Resource Theory Multiple-Resource Theory

9
Divided Attention Guidelines

• Where possible, the number of potential
  sourcesof information should be minimized.
• Where time-sharing is likely to stress a
  personscapacity, the person should be provided
  withinformation about the relative priorities of
  thetasks so that an optimum strategy of
  dividingattention can be formulated.
• Efforts should be made to keep the
  difficultylevel of the tasks as low as possible.

10
Guidelines - continued

• The tasks should be made as dissimilar
  aspossible in terms of demands on
  processingstages, input and output
  modalities,and memory codes.
• Especially when manual tasks are time-sharedwith
  sensory or memory tasks, the greater thelearning
  of the manual task, the less will be itseffect
  on the sensory or memory tasks.

11
Sustained Attention

• Vigilance - Concerns the ability of
  observersto maintain attention and remain alert
  to stimuliover prolonged periods of time.

12
Sustained Attention Guidelines

• Provide appropriate work-rest schedules.
• Provide task variation.
• Increase the conspicuity of the signal.
• Reduce uncertainty as to when and where the
  signal will occur.
• Inject artificial signals and provide operators
  with feedback on their performance.

13
Guidelines - continued

• Provide adequate training of observers to make
  clear the nature of the signals to be identified.
• Improve motivation by emphasizing the importance
  of the task being performed.
• Reduce the rate at which stimuli (which may or
  may not be signals) are presented.
• Maintain noise, temperature, illumination, and
  other environmental factors at optimal levels.

14
Aging Effects Information Processing

• Effects of Age usually do not become noticeable
  until after the age of 65 or so.
• Decrease rate of performance.
• Increased disruption of working memory due to
  shift of attention.

15
Aging Effects - continued

• Difficulty in searching and retrieving material
  from long-term memory.
• Difficulty in dealing with incompatibility.
• Decrements in perceptual encoding of ambiguous
  stimuli.

16
Elderly Design Guidelines

• Designing Information Processing Task for Elderly
• Strengthen amplitude displayed signals.
• Design controls/displays to reduce irrelevant
  details.
• Maintain a high level of conceptual, spatial,
• and movement compatibility.

17
Elderly Guidelines - continued

• Reduce time-sharing demands.
• Provide time between the execution of a response
  and the signal for the next response.
• Allow more time and practice to learn the
  material.