ATTENTION (continued):Capacity Models, Arousal, Multimode Theory

<< ATTENTION (continued):Implications, Treisman’s Model, Norman’s Model

ATTENTION:Subsidiary Task, Capacity Theory, Reaction Time & Accuracy, Implications >>

Cognitive Psychology PSY 504

Lesson 09

ATTENTION (continued)

Capacity Models

Psychologists have become more interested in capacity Demands of different tasks (Kahneman,

1973). Like there is information coming in and then goes to filter and only relevant information is

selected. Different tasks different demands attention diverted to one task to other task. Tasks

require mental effort. People may have some control over where the bottleneck occurs (Johnston

& Heinz, 1978)

Kahneman's Capacity Model

Attention and Effort" was a major work of kahneman (Kahneman, 1973). He shifted the focus

from bottleneck to capacity. There is flexibility in attention, like we can change our attention from

one thing to other thing. There is a lot of evidence that our bottle neck is actually adjustable and it

can be move early to late. A general limit on a person's capacity to perform mental work. A

person has considerable control over how this capacity is allocated.

Daniel Kahneman

He has been doing his work at Princeton University. He has been a pioneer

of cognitive psychology not only in the area of attention but on other areas.

Kahneman's Capacity Model

In this model there are many miscellaneous

determinants that impact sensory system.

Something happens that trigger arousal.

Arousal means some activity starts. Arousal

has many manifestations. Available capacity

of attention will be allocated depending on

the state of arousals. So there is allocation

policy. Then there are some possible

activities. Like the amount of attention is paid

on a task. At the same time there is a

feedback loop. We evaluate how much

attention is needed for the task. Then we

readjust more capacity to that task.

The factors that have impact on allocation

policy are:

Arousal

A physiological state that influences the

distribution of mental capacity in the various

tasks.

Enduring Disposition

An automatic influence where people direct

their attention.

Cognitive Psychology PSY 504

Monetary Intentions

A conscious decision to allocate attention to certain tasks or aspects of the environment.

Example: World Trade Centre

Boeing 707 flying in cloudy weather, at an altitude 200 feet below the top of the WTC was

reported by the airport controller. Alarm buzzed in the airport control tower to signal the danger.

The controller radioed the crew to turn around and climb up to 3000 feet. The controller was

monitoring seven other planes at the time. His attention was diverted to other planes so he could

not pay attention to that plane. So alarm diverted his attention toward that plane.

Bottleneck vs. Capacity

Both models predict that simultaneous activities are likely to interfere with each other. They

attribute the interference to different causes.

Bottleneck: according to this model same mechanism required to perform 2 incompatible tasks.

It is specific. It says same mechanism id needed to those tasks.

Capacity: Demands of 2 activities exceed available capacity then there is problem. It is non-

specific to the task. Total demands of the task, is an important variable.

Both kinds of interference occur (specific and capacity, early selection and late

selection.)

Both kinds of theories are necessary.

Capacity & Stage of Selection

All experiments are showing flexibility of attention. It means we can divert our

attention from one task to other task.

These are also showing an interaction between bottleneck & capacity theories

(Johnston & Heinz, 1978). Listener has control over the location of the bottleneck.

The location can vary from early mode of selection (before recognition) to late

mode of selection (after semantic analysis means meaning analysis).

There is a need to combine capacity model and stage of selection.

Multimode Theory

A theory that proposes that people's intentions and the demands of the task determine the

information processing stage at which information is selected.

Demands of task require greater mental efforts. People's intentions and the demands of task

decide where the attention is paid. We select on the basis of meanings if there are two competing

tasks.

Early Selection vs. Late Selection

Cognitive Psychology PSY 504

According to this theory both early and late selection can occur. Attention is flexible. We can

move our bottleneck and filter. But there must be interaction between bottleneck and capacity.

We can shift our bottleneck to the low level in information processing when we pay attention to

the physical properties of the task. We have a capacity to switch our bottle neck from early to late

or late to early. Late selection will affect the perception of primary message because more

information is selected about the secondary task.

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