Chapter 4 - External Attention

Question 1

Attention

Answer 1

cognitive mechanisms that combine to help us select, modulate, and sustain focus on information that might be most relevant for behavior

capacity-limited: we can only handle small amounts of information at a time

Question 2

External vs Internal Attention

Answer 2

external attention: where we attend outwardly to select and modulate sensory information

internal attention: where we select, modulate, and maintain internally generated information (e.g. thoughts, memories)

not a clear division between the two, and they can influence each other

Question 3

Overt vs Covert Attention

Answer 3

overt attention: moving your eyes to object/location of interest
causes object to fall on fovea of eye
can measure overt attention with eye-trackers

covert attention: moving attention to independent of where eyes are pointed
saccades (eye movements) to a location - preceded by covert attention
use covert attention when tracking multiple objects

Question 4

Selective Attention

Answer 4

ability to focus on one source of information while ignoring all others

Question 5

Attentional Selection

Answer 5

attentional selection is controlled by:

voluntary attention (endogenous): controlled by goals of individual, top-down

reflexive attention (exogenous): attention controlled by environment, bottom-up
salient information “captures” attention

Question 6

Spatial Attention

Answer 6

Posner (1980) likened attention to a spotlight where you select regions of space for special processing

Question 7

Posner - Spatial Cuing Experiment

Answer 7

question: does attention influence time needed to detect a stimulus there?

cue: indicates where a subsequent target may be
valid (correct location)
invalid (incorrect location)
neutral (uninformative)

stimulus onset asynchrony (SOA): the time between the onset of cue and onset of target

Question 8

Selection in Space - Peripheral and Symbolic Cues

Answer 8

peripheral cues: exogenous shifts of attention
stimulus-driven
automatic and faster

symbolic cues: endogenous shifts of attention
goal-driven
volitional and slower

Question 9

Inhibition of Return

Answer 9

once attention visits a location and then shifts away, location is being “inhibited”

Question 10

Feature-Based Attention

Answer 10

can tune attention to select a specific feature (color, motion, orientation)

neurons responsive to that feature
- enhanced response

neurons tuned to other features
- suppressed response

Question 11

Neglect Syndrome

Answer 11

damage to parietal lobe

ignore 1/2 of visual field (space-based)
ignore 1/2 of objects (object-based)

contralesional deficits: right hemisphere damage and the left is neglect, behave as if neglected objects are not present

Question 12

Corbetta & Shulman (2002)

Answer 12

proposed two different attentional networks:

ventrial attention network:
bottom-up attentional control
salient events in environment
exogeneous attentional control

dorsal attention network:
top-down attentional control
goals influence attention
endogenous attentional control

Question 13

Corbetta & Shulman - Theory of Neglect (2002)

Answer 13

patients have damage to stimulus-driven (exogenous) attentional system
many neglect patients have damage to right temporo-parietal junction

normal: objects competing with one another for attention (exogenously)
neglect: objects in neglected field can’t compete for attention

Question 14

Biased Competiton Theory

Answer 14

too much information at any one time
information “competes” for neural control/awareness

stimuli in a cluttered visual environment compete to control the responses of neurons in the visual system

selective attention biases the competition in favor of one stimulus over the other

Question 15

Visual Search

Answer 15

looking for a target in a display containing distractors (e.g. looking for hairbrush on a crowded vanity, looking for a friend at a party)

laboratory search tasks: reaction time to find target plotted as a function of set size (number of distractors)

examine reaction time to find target as function of set size (number of items on display)

feature searches: target defined by single feature, done in parallel with unlimited capacity, reaction time does not increase
conjunction searches: target defined by combo of features, done in serial, reaction time increases with set size

Question 16

Feature Integration Theory (FIT)

Answer 16

Treisman and Gelade (1980)

proposed two different processing stages
preattentive stage
attentive stage

Question 17

Preattentive Stage vs Attentive Stage

Answer 17

preattentive stage: automatic, no effort required
unaware of processing, parallel processing
object analyzed into features

attentive stage: features are combined into object recongition
“binding” of features to object representation, requires focused attention, attention moves serially from item to item

Question 18

FIT and Illusory Conjunctions

Answer 18

Treisman and Schimdt (1982)

primary task: report two black digits
secondary task: describe objects present

participants report combination of features from different stimuli
illusory conjunctions occur because features are “free flowing”

Question 19

Dichotic Listening

Answer 19

1950’s-1960’s - research looking into auditory attention, often used dichotic listening task

one message is presented to the left ear and another to the right
participant “shadows” one message to ensure they are attending to that message

Question 20

Results of Dichotic Listening

Answer 20

participants cannot report the content of the message in unattended ear, failed to notice change in content and language

however, unattended ear is being processed at some level, change from speech to another sound is noticed

Question 21

Broadbent’s (1958) Filter of Selective Attention Theory

Answer 21

multiple inputs from senses, inputs stored briefly in a sensory store

filter controlled what inputs were further processed (all other inputs blocked), filter could select information based on physical characteristics

meaning wasn’t extracted until information passed through Limited Capacity Channel

Question 22

Treisman’s Attenuation Theory

Answer 22

messages enter Attenuator
analyzes incoming messages in terms of physical characteristics, language, and meaning, messages being attended is let through the attenuator at full strength

messages then enter Dictionary Unit
contains words we know, each with different thresholds for being activated
words that are common or important have low thresholds, uncommon words have high thresholds

activated words enter memory (awareness)

Question 23

Deutsch & Deutsch’s Late Selection Model

Answer 23

selection of stimuli for final processing does not occur until after information has been analyzed for meaning

Question 24

Load Theory - Perceptual Load

Answer 24

Lavie & Cox (1997)

subjects performed a search task
ignore flanking letter on outside of ring

low load (easy search) - target pops out, flanker interferes

high load (hard search) - target requires search, attentional resources being used to find target, flanker doesn’t interfere

Question 25

Load Theory - Working Memory Load

Answer 25

working memory load - more irrelevant information processed, tested memory load

results: high memory load had harder time ignoring faces
low memory load had easier time ignoring faces

Question 26

Inattentional Blindness

Answer 26

failure to notice an unexpected item in front of eyes when attention is preoccupied

Question 27

Change Blindness

Answer 27

failure to notice large changes from one view to the next

Question 28

Most & Astur (2007) - Inattentional Blindness and Driving

Answer 28

subjects in driving simulator
follow blue or yellow arrows at intersection and ignore other colored arrows
at intersection, motorcycle swerves in front that either matched or mismatched arrows

results: slower to brake and more likely to hit motorcycle that does not match arrows

Question 29

Temporal Attention

Answer 29

attending to information in time

Question 30

Attentional Control

Answer 30

top-down (endogenous control): attention to locations/objects that help accomplish current goals

bottom-down(exogenous control): salient objects will attract attention

attention might be directed to emotional/dangerous stimuli, might be influenced by anxiety/phobias

Question 31

Attentional Blink

Answer 31

subjects have difficulty reporting the second target if it appears too soon after the first target

attention needs a “resetting period” before a second item can be brought to conscious awareness

Question 32

Attentional Control - Dot Probe Task

Answer 32

Bradely et. al (1999)

tested patients with Generalized Anxiety Disorder (GAD)
pictures of emotional/neutral face replaced by dot
GAD subjects biased towards anger

Question 33

Emotional State

Answer 33

mood may influence attentional scope

Broaden-and-Build Theory: when safe/happy - can expand and take in new experiences
when threatened/anxious - need to keep focus on most relevant things

Question 34

Fredrickson and Brannigan (2005)

Answer 34

subjects watched video clips meant to induce positive or negative emotions

test on local vs. global attention bias
positive mood = choose more “global” matches
negative mood = choose more “local” matches