Download Attention

Selective Attention Videos
The "Door" Study demonstrating "change blindness"
Did You see the Gorilla
The Monkey Business Illusion
Attention Selects Stimuli for Processing
• Attention—or selective attention—is the process of selecting or
focusing on one or more stimuli for enhanced processing and
analysis.
• Arousal is the global level of alertness in an individual.
• Overt attention occurs when the focus coincides with the sensory
orientation, center of visual gaze.
• In covert attention, the focus is independent of sensory
orientation, “secretly” attending to peripheral visual field.
• Cocktail party effect—selectively enhanced attention to filter out
distracting stimuli.
Covert Attention
“Attentional Spotlight”
Attention Selects Stimuli for Processing
• Inattentional blindness
• can occur in a shadowing task using two sources of visual stimuli.
• Subjects fail to perceive nonattended stimuli.
• Change blindness
• is the failure to notice changes when comparing two alternating static
visual scenes.
• Change-detection
• For objects that have evolutionary importance such as other animals
Bottlenecks in Attention
The Stroop Effect
You Tube Video Stroop Effect
Attention May Be Endogenous or Exogenous
• Endogenous attention—or voluntary attention—is directed
toward aspects of the environment in keeping with interests
and goals.
• In this top-down process, higher-order cognitive processes
control lower-order systems, often with conscious control.
• The symbolic cuing task measures reaction time to a
stimulus that is preceded by a hint as to the location it will
appear.
• The cues presented may be valid, or invalid.
Measuring the Effects of Endogenous Shifts of
Attention
ERP Changes in Endogenous Visual Attention
ERP Maps in Exogenous Visual Attention
Attention May Be Endogenous or Exogenous
• Exogenous attention—or reflexive attention—is the
involuntary reorienting of attention toward a stimulus source,
cued by an unexpected object or event.
• In this bottom-up process, lower-order sensory inputs
trigger processing by higher-order systems.
• A peripheral spatial cuing task measures latency to detect a
visual stimulus, when it is preceded by an irrelevant stimulus
in the same location.
• Due to inhibition of return, longer intervals (200 ms or
more) inter f ere with processing of valid cues.
Exogenous Attention and Inhibition of Return
Exogenous and Endogenous Attention Are
Complementary
Early Television Exposure and Subsequent
Attentional Problems in Children
• Television viewing is correlated with decreased attention spans
in children
• Television watched daily at ages 1 and 3 years
• Ten percent of children had attentional problems at age 7
• A 1-SD increase in the number of hours of television watched at
age 1 is associated with a 28% increase in the probability of
having attentional problems at age 7.
• Is this part of the environmental factors that influence the
development of ADHD?
Extensive Television Viewing and the Development of
Attention and Learning Difficulties During Adolescence
• Frequent television viewing during adolescence
– is correlated with an elevated risk for subsequent attention and learning
difficulties after family characteristics and prior cognitive difficulties
were controlled.
– 1 or more hours of television per day at age 14 had more
• poor homework completion, negative attitudes toward school, poor
grades, and long-term academic failure.
– 3 or more hours of television per day increased these problems
– 3 or more hours of television per day also showed
• attention problems
• Less likely to finish college.
– Not because of reciprocal effects between television viewing and
learning difficulties
Development of Attention
• Development of attentional networks
– alerting network matures throughout adolescence and into
adulthood
– orienting network seems to be formed as early as 4 years of age
– executive attention network develops from 4 to 7 years of age
• executive attention might not change much past the age of 7
• however, inhibitory control and emotional regulation development into
adolescence
• between 8 and 12 years of age reduced brain activation
– right-sided frontal-midbrain regions during alerting
– right-sided temporoparietal junction during orienting
– dorsolateral prefrontal cortex during executive control of attention
• children also showed more activation in several regions compared with
the adults
– superior frontal gyrus during orienting
– superior temporal gyrus during executive control of attention
The Immediate Impact of Different Types of Television
on Young Children’s Executive Function
• 4-year-olds watched 9 minutes of either
– Fast paced television cartoon (Sponge Bob)
– http://spongebob.nick.com/videos/clip/spongebob-173b-mrs-puffs-plan-clip.html
– Educational cartoon (PBS of young boy)
– Or drew for 9 minutes
• Immediately tested on 4 tasks assessing executive
function
–
–
–
–
Tower of Hanoi
HTKS task
Delay-of-gratification
Backward digit span
• Children who watched the fast-paced television
cartoon performed significantly worse on the executive
function tasks than children in the other 2 groups
Disorders Provide Clues about the Organization of Attention
Attention-deficit hyperactivity disorder (ADHD) is a
syndrome of distractibility, impulsiveness, and hyperactivity
that, in about 5% of all children, interferes with school
performance.
These children tend to have overall brain volumes reduced
about 3–4%, with reductions most evident in the cerebellum
and in the frontal lobes.
Attention and awareness are behavioral and experiential
manifestations of consciousness but are not synonymous.
Consciousness may be defined as being aware that we are
conscious and perceiving what is going on in our minds and
around us.
Visual Search
Effects of Attentional Spotlights on fMRI Activation
in Visual Cortex
Effect of Selective Attention on the Activity of
Single Visual Neurons
Attentional Remodeling of a Neuron’s Receptive
Field
Shifts of attention between cued locations cause shifts in peak sensitivity within a
receptive field map of one neuron.
Attention can also apparently cause the overall size of receptive fields to shrink,
sharpening the receptive field
Many Brain Regions Are Involved in Processes of
Attention
Several cortical regions are associated with the source or control of
attention.
The lateral intraparietal area—or LIP—is involved in the topdown control of attention in monkeys.
The human homolog to this region is the intraparietal sulcus
(IPS).
Both encode a salience map (or priority map) controlling the
voluntary shifts of attention.
The frontal eye field (FEF) establishes gaze in accordance with
cognitive goals (top-down processes) rather than with
characteristics of stimuli.
The temporoparietal junction (TPJ) helps shift attention to a
new location after target onset.
Cortical Regions Implicated in the Top-Level Control of
Attention
A Frontoparietal Attentional Control Network
The Cortical Attentional Control Network
Disorders Provide Clues about the Organization of Attention
• Damage to the attentional system in the right hemisphere can
cause behavioral changes.
• Hemispatial neglect is a syndrome in which no attention is paid
to one side of the body or to things presented to that side.
• Hemispatial neglect results from damage to the right inferior
parietal cortex.
• Extinction—or extinction of simultaneous double stimulation—is
the inability to recognize stimuli presented to both sides that can
occur with right inferior parietal lesions.
• Anosognosia is the denial of illness, and patients may not
recognize signs of their unilateral neglect, even disclaiming
ownership of their limbs.
Diagnostic Test for Hemispatial Neglect
Brain Damage in Hemispatial Neglect