Chapter 9: attention and executive functions

Question 1

Time-on-task effect

Answer 1

Prolonged sustained attention leads to poorer task performance and an increase in errors.

Question 2

Vigilance tasks

Answer 2

Focusing attention for longer periods in monotonous tasks in which little is happening but a person still has to stay alert for unexpected events.

Question 3

Attention networks theory (Corbetta and Shulman)

Answer 3

Bottom-up attention is a passive attention process which is activated by external, salient stimuli (phasic alertness). This is an automatic process.

Top-down attention is used in situations that require selection, in which the person already knows what to look for. They call this the attentional set, like looking at the screen waiting for a certain number. Top-down attention is linked to attentional control of executive functions.

Question 4

3 functional attentional networks (Posner & Petersen)

Answer 4

1. Vigilance network: allertness
2. Anterior attentional network: active and selective detection of information
3. Posterior attentional network: focusing on visuospatial attention

Question 5

Mental schema theory

Answer 5

This model distinguished routine and non-routine situations:
- Automatic tasks are quick, have no capacity limits and do not require conscious attention. Therefore multiple automatic tasks can be performed at the same time.
- Task that cannot be performed routinely require attentional control. They proceed slowly, require conscious attention and have capacity limits.

Automatic tasks are controlled by mental schemas. The external world consists of many stimuli that fit the actions of the schemas that compete for attention, so a selection mechanism is madatory. This is selected on frequency and recency.

The non-automatic tasks are controlled by the supervisory attentional systems (SAS). This inhibits the routine selection of schemas and switches to using your executive functions, which updates your goal to what you are about to perform. It then monitors and adjusts the execution in comparison to the goal.

Question 6

Multimodal working memory model (Baddely and Hitch)

Answer 6

Working memory contains 3 components:
1. Phonological loop: verbal and phonological (sound) information.
2. Visuospatial sketchpad; maintains visual and spatial information.
3. Central executive: responsible for the management and regulation of cognitive processes.

Question 7

Executive functions

Answer 7

A person’s capacity to maintain an independent, constructively self-serving and socially productive life.

Lezak said that executive functions refer to the question IF a person actually uses their cognitive capacities in a situations that calls for them, and HOW they use them.

Question 8

Shielding-shifting dilemma

Answer 8

Control of goal setting and of behaviour is influenced by: protection against distractions vs. flexible adaptation of a goal.

Goschke and Bolte stated that the balance between stability and flexibility can be influenced by emotions and feelings, which determine the importance of a particular goal. In adolescence the importance of social context grow (emotions), which causes them to be more receptive to explorative/ risky behaviour.

Question 9

Unitary view of executive functions

Answer 9

The idea that executive functions are the ‘central operator’ of behaviour and it is positioned in the prefrontal rotex. At the same time it functions as part of larger brain networks containing other brain regions (also subcortical).

This view can be seen in the multimodal working memory model and mental schema theory.

Question 10

Fractionated view on executive functions

Answer 10

The idea that executive functions include multiple specialized processes, more or less whithout hierarchy.

Stuss and Alexander said that most tests are based on the fractionated idea, since this states that executive functions can be measured seperately.

Question 11

Dorsal attention network

Answer 11

This network regulates the active control of visuospatial attention. It focusses visual attention on an external task.

Question 12

Ventral attention network

Answer 12

Involved in reorientation of attention when a salient stimulus appears, like a fire alarm.

Question 13

Default mode network

Answer 13

Is active when there are no external tasks to perform. This network is self-related, like when you have nothing to do you start thinking about what you are going to have for dinner or your future plans.

Question 14

Measuring selective attention

Answer 14

It is important that we measure this in 2 tasks:
1. It must be performed as quickly as possible without selection
2. It must be a component that is comparable but requires selection.
If the second condition is slower, this indicates that an impairment in selective attention is present.

Question 15

3 types of attentional and executive tasks

Answer 15

1. Operational tasks: as quickly as possible with little cognitive control.
2. Tactical tasks: emphasis on accuracy, but with time pressure. High degree of cognitive control.
3. Strategic tasks: no time pressure and little structure to the task. Requires high cognitive control.