Attention
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The meaning of attention
• Term attention doesn’t mean the same thing to
all people
• We apply the term attention to a huge range of
phenomena, from the basic notion of arousal
and alertness all the way up to consciousness
and awareness.
• Attention: the mental process of concentrating
effort on a stimulus or mental event; an activity
that occurs within the cognitive system, a
process.
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Types of attention
• Input Attention
– Alertness or arousal
– Orienting reflex or response
– Spotlight attention
• Controlled Attention
– Selective attention
– Mental resources and conscious processing
– Supervisory attentional system
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4 interrelated ideas about
attention
» First, we are constantly confronted with much more
information than we can pay attention to;
» Second, there are serious limitations in how much
we can attend to any at one time;
» Third, we can respond to some information and
perform some tasks with little if any attention;
» Fourth, with sufficient practice and knowledge, some
tasks become less and less demanding of our
attentional processes.
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Basic characteristics of attention
• Attention is a mental process that requires
mental resources to direct and focus
mental processes
• These mental resources are limited; the
more attention one tasks requires the less
available for performing others
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Alertness and Arousal
• The nervous syytem must be awake, responsive, and
able to interact with the environment
• Input Attention: The basic processes of getting sensory
information into the cognitive system.
• Explicit Processing: Involving conscious processing,
conscious awareness that a task is being performed, and
usually conscious awareness of the outcome of that
performance.
• Implicit Processing: Processing in which there is no
necessary involvement of conscious awareness.
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Reflexive Attention and the Orienting
Response
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Posner’s results
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Reflexive Attention and the Orienting
Response (con’t.)
Posner’s Spatial cuing task
• Benefit/Facilitation: A faster-than-baseline response
resulting from the useful advance information
• Cost: A response slower than baseline because of the
misleading cue
• Spotlight attention: The mental attention-focusing
mechanisms that prepares you to encode stimulus
information.
Posner concluded from this and related experiments that
the attentional focus subjects were switching was a
thoroughly cognitive phenomenon; it was not tied to eye
movements or other overt behavior but to an internal
focusing mechanism.
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Treisman’s Visual Search:
In this panel, search either for a capital T or a boldfaced
letter. In the following illustrations, search for a boldfaced
capital T.
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Treisman’s Visual Search
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Treisman’s Visual Search
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Contrasting Input and Controlled
Attention
• Treisman’s two conditions provided clear
evidence of both a very quick, automatic
attentional process and a much slower,
more deliberate attention, the type used
for the conjunction search. Input attention
is the fast, automatic process of attention
and the slower one is controlled attention.
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Contrasting Input and Controlled
Attention (con’t.)
• Spotlight attention appears to be rapid,
automatic, and perceptual. It is thereby
distinguished from the slower, controlled or
conscious attention process that matches the
more ordinary connotation of the term attention.
• Conscious or controlled attention prepares us to
respond in a deliberate way to the environment.
It is slower, operates in a more serial fashion,
and is especially influenced by conceptually
driven processes.
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In conclusion…attention
• Three basic senses of the term attention
refer to alertness and arousal, the
orienting reflex, and the spotlight of
attention. These correspond to input
attention, a fast process involved in
encoding environmental stimuli into the
mental system.
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Controlled, Voluntary Attention
• Controlled Attention: Forms of
processing in which there is a deliberate,
voluntary allocation of mental effort or
concentration.
• Selective Attention: The ability to attend
to one source of information while ignoring
or excluding ongoing messages around
us.
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Selective Attention and the Cocktail
Party Effect
• Filtering or selecting: When you try to
ignore the many stimuli or events around
you so you can focus on just one, the ones
you are trying to ignore are distractions
that must be eliminated or excluded. The
mental process of eliminating those
distractions, eliminating unwanted
messages, is called filtering or selecting.
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Selective Attention and the Cocktail
Party Effect (con’t.)
Shadowing Task
A task devised by E. Colin Cherry. In this task, Cherry
recorded spoken messages of different sorts on tape,
then played the tape to a subject who was wearing
headphones. The subject’s task was to “shadow” or
repeat the message to the right ear out loud as soon as
it was heard. In most of the experiments, subjects were
also told to ignore the other message, the one coming to
the left ear.
Conclusions: Subjects could report accurately on a
variety of physical characteristics of the unattended (left
ear) message, but were unable to notice other things
about it.
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Broadbent’s Filter Theory
In Broadbent’s view, the auditory mechanism
acts as a selective filter; regardless of how
many competing channels or messages
are coming in, the filter can be tuned, or
switched, to any one of the messages,
based on characteristics such as loudness
or pitch.
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Broadbent’s filter theory of selective
attention
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Treisman’s Attenuation
Theory
Treisman rejected the ‘early selection’ notion
embodied in Broadbent’s theory. Instead, she
claimed that all incoming messages receive
some amount of low-level analysis, including the
analysis of the physical characteristics of the
message. When the unattended messages yield
no useful or important information, those
messages are attenuated; they are weakened in
their importance to ongoing processing.
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Norman’s Pertinence
Model
Donald Norman proposed a useful modification to
the Treisman scheme; his model specifically
included a mechanism for top-down processing.
The model claims that at any instant in time,
attention to some piece of information, some
message, is determined by two factors, sensory
activation and pertinence.
Pertinence: The momentary importance of
information, whether caused by permanent or
transitory factors.
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Selection Models
• Two things about selection attention:
• First, selective attention can occur very early in the
processing sequence, based on very low-level,
physical characteristics, as Broadbent proposed.
• Second, it can be influenced by both permanent
and temporary factors. Permanent factors include
highly important information such as your name
and highly overlearned and personally important
factors.
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Automatic and Conscious Processing
Theories
• Automaticity: Occurring without conscious
awareness or intention and consuming little if
any of the available mental resources.
• Two explicit theories of automaticity have
been proposed, one by Posner and Snyder, and
one by Shiffrin and Schneider. They differ in
some of their details but are similar in their
overall message.
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Posner and Schneider’s 3
characteristics of an automatic
process
– The process occurs without intention, without
a conscious decision;
– The mental process is not open to conscious
awareness or introspection;
– The process consumes few if any conscious
resources; that is, it consumes little if any
conscious attention.
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Conscious Processing
– The process occurs only with intention, with a
deliberate decision;
– The process is open to awareness and
introspection;
– The process uses conscious resources; that
is, it drains the pool of conscious attentional
capacity
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Automatic and Conscious Processing
The Role of Practice and Memory
Shiffrin and Schneider’s theory of automatic
and conscious processing stresses the
role of repetitive practice.
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Attention and Automaticity
• Attention is essentially conscious mental
resources; we can devote these attentional
resources to only one demanding task at a time
or to two less demanding tasks, as long as the
two together do not exceed the total capacity
available.
• The route to automaticity is practice and
memory. With repetition and overlearning
comes the ability to perform in an automatic
fashion what formerly needed conscious
processing.
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Disadvantages of Automaticity
Mental processes become more automatic
as a function of practice and overlearning.
A disadvantage of automaticity is that it is
difficult to reverse the effects of practice in
an automated task, and automaticity can
lead to errors of inattention.
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A Disorder of Attention: Hemineglect
• Hemineglect: A disruption or decreased
ability to look at something in the (often)
left field of vision and pay attention to it.
Thus, hemineglect is a disorder of
attention in which one half of the
perceptual world is neglected to some
degree and cannot be attended to as
completely or accurately as normal.
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Drawings copied by a patient with contralateral
neglect
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Hemineglect, in conclusion
This order of attention which shows how the
attentional system can be affected by brain
damage, thus informing us about normal
attention. In hemineglect, the patient is unable
to direct attention voluntarily shift attention to the
neglected side of space
The evidence suggests that this arises from an
inability to disengage attention from a stimulus
on the nonneglected side, hence disrupting the
process of shifting attention to the opposite side.
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