attention. limited –allocate attention, switch among tasks; selective –direct search –evaluate...

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Attention

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Attention

LIMITED – Allocate attention, switch among tasks;

SELECTIVE– Direct search

– Evaluate what is not currently in attention

Properties of Attention

Today. . .limited

• What can we say about how attention is allocated?

• What mechanisms do you use to protect the limited resource of attention?

• How do you solve the problem that attention is limited?

Allocation

M W K 5 D

Y P H T E

V A

C GN J

X 7

W L

Sperling & Melchner: Arrays flash by one at a time, 240ms each: subjects are to name the location and identification of the two digits on each trial

Subjects do better if told whether the digits will be in the inner or outer circle of characters.

Question:

Is attention always allocated the way that you want?

Of course not!

What happens that prevents you from allocating attention?

In general we could say that there is distraction from without and distraction from

within.

Allocation: distraction from without

• Sudden, high intensity stimuli in the periphery

• Certain types of stimuli (that aren’t sudden or high intensity) naturally draw attention (examples?)

Question: what strategies do you employ to avoid distraction?

Demonstration

Ask them “How many windows are in your house or apartment?”

When they answer, note whether they look off into the distance, or keep their gaze on you.

Gatekeeper

Strategy 1: Avoid distracting stimuli. Faces are socially important, & it’s hard not to attend to them.

Strategy 2: Habituate

•With continued exposure, distracting stimuli no longer demand attention.

•This is more effective for stimuli that don’t change much; e.g., harder to habituate to music than a refrigerator hum.

•BUT complexity is not so important

If this painting were behind me as we were having a conversation, you would habituate,

because it’s static.

Even this simple scene would be distracting because of the motion

Strategy 3: admit some stuff, not others

• Next class we’ll talk in more detail about how much the gatekeeper can really evaluate about the stimulus

What is the most distracting auditory stimulus?

Allocation: distraction from within

Wegner demo

Wegner theory

Operating process: seeks mental contents consistent with what you want to think about (no white bear)Monitoring process: searches for mental contents that you are NOT supposed to think about (white bear)—this is a warning system that mental control is about to fail.

Operating process demands attention, but monitoring doesn’t; thus if you’re distracted, or tired, operating can’t work, but monitoring can.

Allocation summary

In order to allocate attention as you desire, you must maintain its focus. Distractions may come from outside (stimuli in environment) or inside (your own thoughts).

The cognitive system has strategies to maintain allocation to the desired targets.

Limited attention: problem 2

Problem 1 was distraction—your desired allocation gets messed up.

Problem 2 is the very fact that attention is limited—you can’t do everything you want to do.

How does your system deal with that problem?

When can you go on “auto-pilot?”

Reduction in demands w/ practice

Automatic

Little or no attentional cost

With or without intention

Not affected by motivation

Can happen w/o awareness

Attentional cost

Occurs only with intention

Affected by motivation

Only with awareness

Controlled

Training to automaticity: Shiffrin & Schneider (1977)

G

F

A L I F

A A L A

I F

L

B

K J

L

What effect will # of figures on each card have on errors?

Results:

1 2 3 4

Number of figures on each card

Err

ors

Early in training

Results:

1 2 3 4

Number of figures on each card

Err

ors

After 2100 trials

Early in training

Spelke, Hirst, & Neisser

• Sought automaticity for more complex tasks

• Subjects read stories while they took dictation

• Initially,huge interference

• An hour-long session , 5 days/ week, for six weeks

• Developed automaticity.

Example of automatic process: reading

Name the ink colors.

Example: “Lion” say “red”

LION BEAR TIGER LION

LION LION BEAR BEAR

TIGER BEAR TIGER LION

TIGER LION BEAR TIGER

LION BEAR LION LION

BEAR LION TIGER BEAR

TIGER LION TIGER LION

GREEN RED RED GREEN

LION GREEN BLUE BLUE

RED RED GREEN BLUE

GREEN RED GREEN RED

BLUE GREEN RED BLUE

BLUE RED BLUE GREEN

BLUE GREEN RED GREEN

THE POINT

Reading is automatic and therefore happens without intention: even when you don’t want it to happen, it does.

This phenomenon is limited by context: e.g, stoplight.

cf interference in sports. . .

Summary

• Attention is limited• To deal with this limitation, we allocate it,

and we make frequently practiced tasks automatic

• In trying to allocate attention, there are potential distractions, both internal and external

• We have strategies for dealing with these