3 – Selective Attention selective attention attending to part of the environment while ignoring the rest Examples Listening to instructor while ignoring.

3 – Selective Attention

selective attention attending to part of the environment while ignoring the rest

Examples

Listening to instructor while ignoring everything else

Looking around a room for the face of your friend

Spotlight Metaphor

We must limit the scope of our attention because “attentional resources” are

limited

Example

basketball pass demo (1:22)

www.dansimons.com/videos.html (videos 1 and 2)

or www.youtube.com/watch?v=vJG698U2Mvo

http://www.dansimons.com/videos.html

http://www.youtube.com/watch?v=vJG698U2Mvo

Inattentional Blindness failure to notice salient object even if looking directly at it.

Experiment

Ss watched video of people passing basketballs.

Ss told to count passes.

About 50% of Ss didn’t notice gorilla.

(Simons & Chabris, 2001)

Real world example

Car driver makes left turn without noticing oncoming motorcycle.

Note that unnoticed object is 1) not expected

2) not looked for

Radiologists were shown this lung scan and asked to look for “cancer nodule”83% failed to notice

Drew and Wolfe (201X)

blank

Change Blindness failure to notice change in object while it is briefly out of view

Person-Swap Experiment

S entered laboratory to participate in study and meets E.

E surreptitiously traded places with different E.

Some Ss didn’t notice.

Note the distinction:

inattentional blindness Not noticing object

change blindness Not noticing change in

object (or scene)

Videos with Demos

Person-Swap in lab (3:59) www.youtube.com/watch?v=38XO7ac9eSs&feature=related

More demos (2:10, 1:17) www.dansimons.com/videos.html (first panel, videos 3 and 4)

Dan Simons

http://www.youtube.com/watch?v=38XO7ac9eSs&feature=related


Another Person-Swap Experiment

E asks S for directions.

S begins to give directions.

While E briefly out of view, E covertly trades places with another E.

About 50% of Ss didn’t notice.

(Simons & Levin, 1998)

video (1:36)

www.dansimons.com/videos.html second panel, video 1


Flicker task demo (photos from Rensink et al., 1997)

animation


use cursor keys: R…R, R, L, L, R, R, L, L,

Flicker task demo (photos from Hollingworth, Schrock, & Henderson, 2001)




Flicker Effect

1. S sees scene, brief blank screen, and then altered version of scene

brief

blank screen

2. Alternations continue (“flickers”) until S identifies change

3. S is told to find the change

4. Finding the change takes a long time (flicker effect)

Note: the flicker effect is a kind of change blindness

Demos

www2.psych.ubc.ca/~rensink/flicker/download/indeT.html

http://www2.psych.ubc.ca/~rensink/flicker/download/index.html

Flicker Effect Experiment

Original and altered scenes scene alternated until S identified the change

blank screen

blank screen

240 ms X ms

240 ms X ms

Duration of blank screen = 0 or 80 ms

Results Blank Duration Mean # of Alternations

0

1 (no change blindness)

80 ms

16 (change blindness)

Conclusions

Change blindness occurs if scene must be stored in memory - even for a

moment.

Thus, we can store only a very brief amount of the information in a visual scene

(Rensink et al., 1997)

no gap demo nivea.psycho.univ-paris5.fr/ECS/bagchangeNoflick.gif

http://nivea.psycho.univ-paris5.fr/ECS/bagchangeNoflick.gif

Attentional Capture

Noticing a sudden change in object (or part of scene) to which you are not attending

Stimuli that capture attention

Flicker Task without intervening blank screen

Scream

Siren

Ringing phone

Brake lights on the car in front of you

Some changes capture attention better than others.

Change in Stimulus Efficacy

Example

Increased intensity okay Tail

lights get brighter.

Onset good

Rear window light turns on.

Repeated onset-offset better Brake lights

flash.

Example.

On some cars,

brake lights flash if speed > 50 km /hr

500sec.com/adaptive-brake-light/

http://500sec.com/adaptive-brake-light/

Resisting Attentional Capture

In most situations, attentional capture is adaptive

While walking in woods, we notice snake in our path.

Air traffic controller notices flashing red light

In some situations, we must be able to resist attentional capture.

Example

School bus driver must ignore yelling kids

Student taking test must ignore coughs, door slams, etc.

Naturally, people vary in the ability to resist attentional capture

Experiment : Resisting Attentional Capture

Ss told to look at cross (+) and ignore intermittently flashing circles.

Square appeared in top or bottom location. (This repeated many times)

Ss pressed top or bottom key, respectively.

Results: ADHD kids made far more errors than controls did.

Implication: ADHD kids have a hard time resisting attentional capture.

(Bourel-Ponchel et al., 2010)

In 1913 Danish physicist Neils Bohr’s eponymous Model postulated atoms were formed of electrons orbiting a nucleus, much like planets around the sun – only using electrostatic attraction rather than gravity. Electrons have since been shown to be more akin to waves surrounding the nucleus, but teams in Austria and the US have shown they can be made to perform in the same way as planetary systems, and the technique can be used to change the overall size of the atom.The research, published in the journal Physical Review Letters was inspired in part by the function of Jupiter’s Lagrange points: Two specific points where forces of the Sun and the largest planetary gravity well in the Solar System cancel each other out. These collect matter, known as the Trojans, and the best guess is that the two belts contain more than a million asteroids over a kilometer in diameter.A team at the Vienna University of Technology performed the mathematics for the experiment and Rice University performed the actual experiment. They fired an atomic beam through a vacuum chamber and then crossed the stream with a tuned laser oscillating with the orbital period frequency of the electron around the nucleus.The laser created a localized electronic state that moves in a near-circular orbit around the nucleus, and they could then extend and reduce the size of the orbit by modulating the laser’s frequency. The team got an atom up to the size of a human blood cell during testing.The electron can only be controlled when the force is applied and then reverts to its natural state within a few cycles. Then again, Jupiter is not perfect either. Simulations suggest 17 per cent of the Trojans are unstable enough to fall out of the orbits and go wandering, potentially Earthward bound.The next step is to see if the technique can be used on multiple atoms simultaneously, and to monitor how they interact with each other during operations. Sandwiched between venerable classical physics and the extremes of quantum studies, mesoscopic physics is very much the red-headed stepchild of the physical sciences, but has huge potential. It generally deals with objects from an atom up to 1,000 nanometers – about the size of the average bacterium. By investigating the boundaries between the sub-atomic quantum world and everyday physics, mesoscopic scientists hope to find usable results that could have applications in both fields.

A team of scientists have discovered over 40 new species in southwestern Suriname survey.The team performed a three-week survey in three remote sites along the Kutari and Sipaliwini Rivers.“The goal of this expedition was to bring together the knowledge and expertise of local people with scientific knowledge to study and plan for monitoring of biological and cultural resources of the region.” The scientists surveyed a total of 1,300 species, including 400 plants, 90 aquatic beetles, 90 dung beetles, 76 katydids, 93 dragonflies and damselflies, 100 fishes, 57 reptiles and amphibians, 323 birds, 41 small mammals, 29 medium and large mammals.They also saw 14 threatened species of plants and animals that are listed on the International Union for Conservation of Nature’s Red List.Part of the list of new species includes a “cowboy frog” and a spiked species of armored catfish.The cowboy frog has white fringes along the legs, and a spur on the “heel.” The armored catfish has external bony plates and is covered with spines to help defend itself from giant piranhas.The researchers said that one of the local guides was about to eat the armored catfish as a snack, until scientists noticed its unique characteristics and preserved it.The team also found a “Great Horned Beetle” on their expedition. This beetle is “the size of a tangerine” and weighs over 0.2 ounces. It is metallic blue and purple, and posses a horn on its head used as a weapon to fight in battle.“The area was paradise for the entomologists among us, with spectacular and unique insects everywhere. I didn’t even have to look for ants because they jumped out at me”, Dr. Leeanne Alonso, a former CI RAP Director who is now with Global Wildlife Conservation, said in a press release.

Right Ear Left Ear

neurology intersect apparent defective treatable orangutan qualitative illusion totem pole dangle

penetratealphabetical teacup sarcophagus moonlight formulation motif bondage furthermore integration

scooter mission amplitude kitchen genre selection maroondoubleexpressionbucketful

accentuate spectacular gargantuanheading pivothumanist mainsail collectible xylophonecollection

chargingtrample mansion revision bluebird streaky famous remover uplifting sought

overrun cohabit exhortation envoy widen platitude opulence uncover ruckusdifficulty

perpetuate crouch veritable deflect foray cape redundancy transposition capability geese

inhabit cafeteria intellectual induction ammonia reindeer wrench sidetrack biologyinstance

Right Ear Left Ear

Dichotic Listening Procedure

S hears words in one ear while simultaneously hearing different words in other ear.

S is told “left” or “right” and then attends to the message in that ear.

S repeats attended message aloud (shadow)

Trial continues for 10-60 s.

Then, S is asked about unattended message.

Dichotic Listening Experiment

S heard prose in one ear; word list in other ear. Subjects shadowed the prose.

Immediately afterwards, S asked about unattended message

Results: Ss can say unattended words were English

But Ss couldn’t recall any of the words!

This was true even if the list included the same word 35 times in a

row!

Conclusion

Our mind does not “process” the meaning of unattended message.

(e.g., Broadbent, 1957; Cherry, 1953; Moray, 1959)

It was the best of times, it was the worst of times.

dog, wall, green, bell, anger, wish, tiger, sky,

Early dichotic listening studies suggest that we can process only one message at a time.

However, we know that this is not entirely true.

Example

cocktail party effect - we notice our name used in nearby unattended

conversation

Might our minds process information other than our name, without our awareness?

Dichotic Listening Experiment 2

Ss heard two stories, one in each ear.

After 20-30 s, and without warning, the stories unexpectedly switched ears.

Results After switch, Ss often shadowed wrong prose because it made

sense.

“I saw the girl skipping, er, big gray

rabbit …”

Conclusion Ss understood the meaning of the unattended message!

(Treisman, 1960)

Since then, 1000s of follow-up studies have been done.

Most researchers believe we can “partly” process meaning of unattended message.

I saw the girl [switch]big gray rabbit

The fox chased [switch]

skipping rope

Neglect disorder in which patient “ignores” objects in left or right visual field.

Example

Patient asked to copy model on left.

Patient’s drawing is shown on right.

(continued)

Facts about neglect

Left neglect is far more common than right neglect.

Common symptoms

Leave one shoe off

Leave food on one side of plate

Shave one half of face

Patients notice object on left side if they turn all the way around to the right.

Video

Patient draws daisies (3:19) www.youtube.com/watch?v=ymKvS0XsM4w

(Bisiach, 1996)

http://www.youtube.com/watch?v=ymKvS0XsM4w

(McCarley et al., 2004)

Visual Search

search for an object within a visual scene

Examples

Looking for car in crowded parking lot

Finding certain brand of cereal on grocery story shelf

Airport worker looking for knife in luggage scan

(Image from McCarley et al., 2004)

Typical Visual Search Experiment

S told what the target is.

Computer screen shows one target and 1 – 50 distractors.

S presses yes-key if target is there, no-key if target is not.

E measures RT.

Examples Find the I Find the I

1 distractor 50 distractors

(Treisman & Souther, 1985; Wolfe, 2001)

L L L L LL L L L L L L L LL L L L L LL L L L L L L LL L LL LL L L I L L LL L LL L L L L L L L

L

I

Find I among Ls

L L L L L L L

L LL L L

L L L I L L

L LL L L L

LL L L L

L L LL L

L LL L L L L L L L L L L L

L L L L

Find I among Ls (again)

L L L L L L LL L L LL L L

L L L L L L L L L L L L

L L L L

L L L L L L L L L L L

L L L L L L L

I L L L L L L LL


L L L L L L L

L L L LL L L L

L L LL L L L

L L L L L L L

L L LL L

L L L L

L L L LL L L


I

L


L L L L L L L LL L

L L L L LL L L

L L L

L I L L L

L L LL L L LL L L L L L

L L L LL L

Find P among Bs

B B B B B B B

B B B B B B B BB B

B BB B B

B BB B BB B B B

B B P B BB B B B B BB B B B B

B B B B B

Find P among Bs (again)

B B B B B B BB B B

B B B BB B P B B

B B B B B B BB B B B

B B B B B B B B B B B B

B B B B B B B

B B B B B B BB B


B B B B B B B

B B B BB B B B

B B BB B B B

B B B B B B B

B B BB B

B B B B

B B B BB B B


B B B B B B BB B B

B B B B

B B B B

B B B B P B

B BB B

B B B BB B B B

B B B B B B B B B

Do all searches take longer when more distractors are added?

Find T among Ts

T T T T T T T T T T

T T T T T T T T

T T T T T T T T

T T T T T T T

T T T T T T T T

T T

T T T T T T T T T

Find among s

Can a target pop out if it’s the same color as the distractors?

Find X among Os

O O O O O

O O O O

O O O O

O O O

O O O O

O O O

O X O O

O O O O

O O O O

O O O

O O O O O O O O

O

Find X among Os (again)

O

X

Find X among Os (again)

O O O O O

O O O O

O O O O

O O O

O O O O

O O O

O O O

O O O O

O O O O

O O O

O O O O O O O O

O

Find | among

¾

¾ |

¾

¾

¾

¾

Two kinds of visual searches

pop-out RT unaffected by more distractors serial RT increases with more distractors(as if checking all items at once) (as if checking one object at a time)

Find X Find P

slope 0 slope 30 ms / item

Thus, all items are checked “instantly” Thus, 30 ms = average time to check

RT

# of distractors

Find Pamong Bs

B B B B B B BB B B B B

B B B B BB B B BB

B BB B B B B B B

B B P B BB B B B B B B BB B B B B B B B

RT

# of distractors

30 ms

1 item

Theoretical interpretation

Pop-out search is Serial search is

pre-attentional attentional

1) automatic 1) volitional

2) nearly unlimited capacity 2) very limited capacity

The big question:

What determines whether a target pops-out (i.e., is found without attention)?

Find O among Qs

Q Q Q Q QQ

Q Q Q

Q Q Q Q

Q Q Q Q Q

Q O Q Q Q

Q Q Q Q Q

Q Q Q Q

Q Q Q Q

Q Q Q Q Q

Q Q Q Q

Find O among Qs (again)

Q Q Q Q

Q Q Q

Q Q Q Q Q

Q Q Q

Q Q Q Q Q O

Q Q Q

Q Q Q Q Q

Q Q Q Q Q

Q Q Q Q Q

Q


Q Q Q Q Q Q

Q Q

Q Q Q Q

Q Q Q Q

Q Q Q Q QQ

Q Q Q

Q Q Q

Q Q Q Q Q Q

O Q Q Q Q

Q Q Q Q


Q Q Q Q QQ

Q Q Q

Q Q Q Q

Q Q Q Q Q

Q Q Q Q

Q Q Q Q Q

Q Q Q Q

Q Q Q Q

Q Q Q Q Q

Q Q Q Q


Q

O

What if we switch target and distractors?

O among Qs serial

What about Q among Os?

Find Q among Os

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O OO O O O O O O O O O Q O

Find Q among Os (again)

O O O O O O O O O OO O O O O Q O O O O O O OO O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

Summary

X among Os pop-out

| among s pop-out

O among Qs serialQ among Os pop-out

Hypothesis?

feature-presence search You can simply look for presence of a distinguishing feature

Always pop-out

Examples

Search for object with black color

Search for object with X-shape

Search for object with vertical orientation

feature-absence search You must look for absence of distinguishing feature

Always serial

Examples

Must search for object without horizontal line

Must search for object without double hump

Must search for object without vertical line

Find Pamong Bs


B B B B BB B B BB

B BB B B B B B B


What if search has two kinds of distractors?

Find X among Ts and Os

T T O T O T

T O O T

O T O O T

O T O O T

T O O T O

O T O T O

O T O O T T

O X O T

O O T T O T

O T O O

T T O T O T

O O T T

Find T among Ts and Os

T T O T O T

T O O T

O T O O T

O T O O T

T O O T O

O T O T O

O T O O T T

O T O T

O O T T O T

O T O O

T T O T O T

O O T T

T among Ts and Os pop-out

What about T among Ts and Os ?

T among Ts pop-out

T among Os pop-out

Find T among Ts and Os

T T O T O T

T O O T

O T O O T

O T O O T

T O O T O

O T O T O

O T O O T T

T T O T

O O T T O T

O T O O

T T O T O T

O O T T

Find T among Ts and Os (again)

T T O T O T

T O O T

T T O O T

O T O O T

T O O T O

O T O T O

O T O O T T

O T O T

O O T T O T

O T O O

T T O T O T

O O T T

Find T among Ts and Os (again)

T T O T O T T O O T

O T O O T O T O O

T

TO O T O O T O T

O

O T O O T T O T

O T

O O T T O T O T T O

T T O T O T O O T T

Find among s and s

Find among s and s

Find O among Os and Ns and Ns

feature conjunction search You must look for presence of two distinguishing features

Always serial

Example Find

Must find object that is black AND vertical

- - - - - - - -

Note distinction:

Target can be found by looking for object with one distinguishing feature pop-out

Target can be found only by looking for object with two distinguishing features serial

Overview of Demonstrations

distinguishingkind of

target distractors feature search result

I L horizontal bar

absence serial

X O X shape

presence pop-out

red X blue X red

presence pop-out

| vertical-ness

presence pop-out

Q O hook

presence pop-out

O Q hook

absence serial

red X blue T, green O red or X-shape presence

pop-out

red T blue T, green O red

presence pop-out

red T blue T, red O red and T -shape

conjunction serial

Which search produces pop-out, if either?

O among Cs

C among Os

Find O among Cs

C C C C C C C C

C C C C C C C C C CC C C C C C C C C C C C C C C C C CC C C C C C O C C C C C C C C C C CC C C C C C C C C

Find O among Cs (again)

C C C C C C O C CC C C C C C C C CC C C C C C C C C C C C C C C C C CC C C C C C C C C C C C C C C C C CC C C C C C C C C

Find O among Cs (again)

C C C C C C C C C

C C C C C C C C

C C C C C C C C C CC C C C C C O C C C C C C C C C C CC C C C C C C C C

Find C among Os

O O O O O O O O

O O O O O O O O O OO C O O O O O O O O O O O O O O O OO O O O O O O O O O O O O O O O O OO O O O O O O O O

Find C among Os (again)

O O O O O O O O OO O O O O O O O OO O O O O O O O OO O O O O O O O O O O O O O O C O OO O O O O O O O OO O O O O O O O O

Find C among Os (again)

O O O O O O O O OO O O O O O O O OO O O O O O O O OO O O O O O O O O O O O O O O O C O O O O O O O O O OO O O O O O O O O

C among Os O among Cs pop-out serial

Find

Find

More Asymmetries

Kristjansson & Tse (2001)

A different kind of asymmetry

pop-out serial

Enns & Rensink (1991)

Search Asymmetries

In some cases, swapping target and distractors changes search from serial to pop-out

(e.g., Wolfe, 2001)

With complex targets, RT slopes are steep

Find

Find “square”

Find normal face

Other questions…

Is a slow search even slower if distractors are not known in advance?

Find X

vs.

Find X among Xs and Os

Is feature-present search slower if there are many kinds of distractors?

Find T among Ts and Ts

vs.

Find T among Ts, Ts, Ts, Ts, Ts, and Ts

Still more searches Find

Find

(e.g., Li et al., 2008; Pinto et al., 2010, Wolfe, 2003; 2005)

Practice Questionsdistinguishing kind of

target distractors feature searchresult

red T blue T red

presence pop-out

red red | horizontal orientation presence

pop-out

red T blue O red or T presence

pop-out

blue T red T, blue O blue and T conjunction

serial

red T green T, blue O red presence

pop-out

Target = BLUE Q. Search is serial. Identify distractors.

C

A. red Qs B. blue Os C. blue Ts, red Qs

D. red Ts, green Qs

Target = GREEN O, Search is serial. Identify distractors.

B

A. red Os B. green Qs C. red Ts, blue Os

D. red Qs, blue Os

More Practice Questions

If one looks for a green I among green Ls, what kind of search is it? B

A. feature presence B. feature absence C. feature conjunction

If one looks for a blue O among red Os and green Ts, what kind of search is it? A


If one looks for a blue O among red Os and blue Ts, what kind of search is it? C


If RT is unaffected by the number of distractors, what kind of search is it? A


The End

gorilla study based on earlier study by Neisser and Becklen (1975)

Dichotic listening studies (and 1000s of other studies) have led to two camps.

early selection theory

Early on, one message must be selected for processing of meaning.

Sample Evidence: Ss who didn’t notice “monsoon.”

late selection theory

Both messages can be partly processed before one must be selected.

Sample Evidence: Ss who shadowed wrong message after switch.

Truth is a complicated hybrid of two theories.

Unattended message processed “to some degree.”

Rancorous debate continues.

Selective Attention attending to part of the environment while ignoring the rest

Examples

Reading a book while ignoring extraneous noise

Selective Attention Demo.

First read the bold text. Then read the italicized text.

The Every fact man that gets some a geniuses narrower were and laughed narrower

at field does of not knowledge imply in that which all he who must are be laughed an

at expert are in geniuses. order They to laughed compete at with Columbus, other

they people. laughed The at specialist Fulton, knows they more laughed and at more

the about Wright less brothers. and But less they and also finally laughed knows at

everything Bozo about the nothing. Clown.

Konrad Carl Lorenz Sagan

The ability to “selective attend” varies across individuals.

Example

Classroom noise affects test scores of some people more than others.

Selective attention ability predicts performance on some tasks.

Correlational Study

E measured selective attention of fighter pilots (using auditory task).

Selective attention scores predicted flying skill (even though flying is visual).

However, ability to selectively attend might impair performance on some tasks.

(Carretta et al., 1976; Gopher & Kahneman, 1971; Mihal & Barett, 1976)

Everyone knows what attention is.

(James, 1890)

A formal definition of the term “attention” is not presently available…

(Pashler & Johnston, 1998)

Since 9/11 attacks, government has funded studies of visual search of luggage

Sample ETperiment

Ss see many luggage scans.

1 in 5 scans include knife.

Knife shape and orientation vary.

Ss “stop bag” if they see knife.

Results

Practice improves performance only if target similar to recently seen targets

Conclusion

Practice might not improve performance.

(e.g., McCarley et al., 2004; 2010)

Find E among Fs

F F F F F F

F F F F

F F F F F F

F F F F

F F F F F F

F F F F

F F F F F F

F F F F

F F F F F F

F F F F

F F F F F F

E F F F

Find E among Fs (again)

F F F F F F

F F F F

F F F F F F

F F F F

F F F F F F

F F F F

F E F F F F

F F F F

F F F F F F

F F F F

F F F F F F

F F F F


F F F F F F

F F F F

F F F F F F

F F F F

F F F F F F

F F F F

F F F F F F

F F F F

F F F F F F

F F F F

F F F F F F

F F F F


F F F F F F

F F F F

F F F F F F

F F E F

F F F F F F

F F F F

F F F F F F

F F F F

F F F F F F

F F F F

F F F F F F

F F F F


F

E


F F F F F F

F F F F

F F F F F F

F F E F

F F F F F F

F F F F

F F F F F F

F F F F

F F F F F F

F F F F

F F F F F F

F F F F

What if we switch target and distractors?

Find F among Es

Find F among Es

E E E E E

E E E E E

E E E E E

E E E E E

E E E E E

E E E E E

E E E E E

E E E E E

E E E E E

E F E E E

E E E E E

E E E E E

Find F among Es (again)

E E E E E

E E E E E

E E E E E

E E E E E

E E E E E

E E E E E

E E E E E

E E E E E

E E E E E

E E E E E

E F E E E

E E E E E

Find F among Es (again)

E

E

F

Interpreting slope when visual search is serial

ETample

slope = 40 ms / eTtra item

Thus, it takes 40 ms to scan each item (on average)

RT

# of distractors

40 ms1 item

Two kinds of visual searches

Slow RT increases with more distractors Fast RT unaffected by more distractors

Find P Find T

slope = rise / run = 40 ms/ item

slope = average amount of time to check each item

RT

# of distractors

RT

# of distractors

Find Pamong Bs


B B B B BB B B BB

B BB B B B B B B


Some ugly technicalities.

1. Sometimes, serial search is few items at a time, not one a time.

2. With parallel pop-out, slope is not quite zero but still very small.

We will ignore the above.

The important question: what determines whether search is serial or parallel?

Summary of Results: 3 kinds of visual search

feature presence fast

target has at least one distinguishing feature

T among Os

Q among Os

red T among blue Ts, green Os

feature absence slow

can find target only by finding the object without distinguishing feature

O among Qs

feature conjunction slow

can find target by looking for object with at least two distinguishing features

red T among blue Ts, red Os

3 – Selective Attention selective attention attending to part of the environment while ignoring the rest Examples Listening to instructor while ignoring.

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