Lecture 3

Question 1

What is the Posner Cuing Task and what does it shows?

Answer 1

• It is a task where an arrow gives a valid or invalid cue about where the stimulus will be, you have to respond to this stimulus
• it shows that when the cue is invalid, it takes time to switch your attention towards the cue, reducing response time.

Question 2

What is the visual search task? And what are feature search and conjunction search?

Answer 2

• You have to say whether of not a specific item is presented
• in feature search, the target item stands out from the distractors because it has a feature that none of the there items has
• In conjunction search you have to serially pay attention to each item because they all share some characteristic with the target item.

Question 3

Why does it take longer to detect it when an item is not presented in the visual search task?

Answer 3

Because you have to serially pay attention to every single item to conclude that it is missing.

Question 3

How is the reaction time affected in the Visual Search Task by increasing the amount of items?

Answer 3

• The feature search is barely affected because it uses parallel processing
• The conjunction search is affected because it uses serial processing

Question 4

What are Event-related Potentials (ERP)? What are N and P? and how can you use it?

Answer 4

• You average out several measurements of a cognitive process to filter out noise.
• N is a negative potential and P is a positive potential
• you use it to determine which potentials are affected by a cognitive process.

Question 5

What do more extreme peaks represent in cognitive processes? And what does C1 show?

Answer 5

• They indicate that the brain does more processing.
• C1 shows that attention does not affect the first stage of processing.

Question 5

What does N400 ERP and N600 ERP represent in cognitive processing?

Answer 5

• N400 ERP is for processing word meaning (semantic)
• N600 ERP is for processing word grammar (Synactic)

Question 6

What did Ganis et al measure about imagery, what was the conclusion

Answer 6

• They measured brain activity in imagery vs perception.
• The conclusion was that occipital lobe is activated more for perception, but also a bit for imagery.

Question 6

What did Peterson et al measure?

Answer 6

He measured the difference between semantic and syntactic processes and made sure that only the cognitive process was different between the control and manipulated condition.

Question 6

What do PET/fMRI scans measure and how can you use this?

Answer 6

It measures blood flow toward an active brain region to see if it is active for a cognitive task.

Question 6

How was TMS used to compare perception and imagery for the occipital lobe? What can be concluded?

Answer 6

• The perception and imagery groups where exposed to TMS at the occipital lobe
• The result for both was that the reaction time slowed.
• You can now conclude that occipital is needed for both processes

Question 7

What is the TMS method used for?

Answer 7

• It uses a large coil that disrupts brain activity in a specific region
• Then you see if a cognitive process depends on this brain region.

Question 8

What is sham TMS?

Answer 8

A control condition for TMS that does not actually do anything.

Question 9

What is converging and conflicting evidence

Answer 9

• Converging evidence shows that several measuring methods get the same results
• Conflicting evidence shows that several measuring methods yield (seemingly) different results.

Question 10

What did Martinez et al study?

Answer 10

• They did an fMRI and ERP on a Posner cuing task.
• fMRI showed that V1 switches hemispheres when you alter the location
• ERP showed that C1 was unaffected.
• This is conflicting evidence because V1 is early processing
• However, V1 only seems active in fMRI because it gets feedback from late processing regions. (poor temporal resolution)