Lecture 8 - Object Based Attention and the Cognitive Neuropsychology of Attention

Question 1

Does Attention act on SPACE or OBJECTS?

Answer 1

Spotlight theory, FIT assume that attention acts on a region of space.
However, there is evidence that we actually attend to objects within space, and not just a region of space and all that is in that space.

Question 2

What theories assume that attention acts on a region of space?

Answer 2

Spotlight theory, Feature Integration Theory.

Question 3

What evidence is there that attentions acts on objects in space?

Question 4

In Rock adn Gutman (1981) what experiment did they do and what did this experiments show in regards to whether attention was space or object-based?

Answer 4

Participants shown two figures occupying the same region of space, but had different shapes and colour.
Participants asked to rate the aesthetic appeal of the shape of one of the figures/shapes (to get them to attend to just one of the figures) and the participants memory of the shape of the figure was examined. They had good memory of the shape they attended to and no memory of the other figure. This suggests that people attend to objects (even if multiple objects occupy the same space) and not space alone/everything in a region of space.

Question 5

What did Tipper (1985) do as a follow on from Rock and Guttman’s experiment?

Question 6

What does NEGATIVE PRIMING refer to when talking about attention?

Question 7

What do the findings of Rock and Guttman and The Negative Priming experiments show in regards to attention being object or space-based?

Question 8

What was Duncan’s 1994 experiment on attention? Did it provide evidence for or against the object-based theory of attention?

Question 9

What does the Spotlight Theory of Attention posit about what we attend to?

Question 10

What was the experiment done by Egly et al. (1994) which looked at the effect of Cuing Object-Based Attention? Did this experiment provide evidence for space- or object-based theories of attention?

Question 11

What was the experiment done by Moore et al. (1998) as a follow-on Egly et al. (1994)?

Question 12

In a neuroimaging study looking at the effect of images of house and face superimposed on each other, what was found in regards to PPA and FFA?

Question 13

What is Visual Neglect?

Answer 13

A selective deficit in vision. More accurately could be called attentional neglect.
Right parietal lobe damage leads to left visual field neglect.
Most commonly occurs after stroke.

Question 14

When someone has Visual Neglect where will they likely have damage in their brain?

Answer 14

Right parietal lobe.
Parietal lobe damage affects the where pathway.
Right parietal lobe damage leads to left visual flied neglect.

Question 15

What are the two pathways of visual processing?

Answer 15

The where and what pathway. The dorsal pathway (where pathway) and the ventral pathway (what pathway).

Question 16

If Visual Neglect occurs due to damage to the right parietal lobe and results in visual neglect of the left visual field, then why doesn’t it occur in the right visual field or why is mostly associated with the right hemisphere and why wouldn’t damage to the left parietal lobe result in right visual field damage?

Question 17

Michael Posner examined his classic cuing experiment to look at whether cuing effects are seen in people with right parietal lobe damage. What did Posner find, and what did this provide evidence for regarding Visual Neglect?

Question 18

What is Balint’s Syndrome?

Question 19

What is Simultanagnosia?

Answer 19

Lack of knowledge about simultaneous things. People cannot move their eyes around and their attention is focused on a single object.

Question 20

What is Feature Integration Theory?

Question 21

Who was patient RM?

Answer 21

Had Baliant’s Syndrome - prone to illusory conjunctions - combing features of multiple objects to create/perceive a single object.

Question 22

What are the space-based and object-based explanations of Visual Neglect?

Question 23

What is inhibition of return?

Answer 23

If an area is cued and then there is a long delay (350-500ms) then follow it with a target at the cued location then RTs are longer than if the target was at the un-cued location.

Question 24

When do we see reversing of cuing effects (aka Inhibition of Return)?

Question 25

What experiment did Tipper (1991) do in regards to Inhibition of Return and what did the results provide evidence for in regards to IOR?

Answer 25

Found that the MRT for valid cued markers were longer than for invalid markers, suggesting that IOR is object-based and not just space-based.

Question 26

Is Inhibition of Return an object- or space-based attentional phenomenon?

Answer 26

Appears to be an object-based phenomenon.

Question 27

Behrmann and Tipper (1994) did an experiment looking at whether Visual Neglext was Object or Space-Based. What was this experiment and what did it show?

Question 28

In Rock and Gutman’s (1981) experiment that asked participants to rate the aesthetic appeal of two overlapping objects, what did they find about the participant’s memory for the objects they were not asked to rate and what did this mean for theories of attention at the time?

Answer 28

They found that participants did not have any memory for the unattended objects, despite them occupying the same area of space.
This data was used as evidence for the idea that attention is object-based and not space-based as proposed by theories such as Spotlight Theory and Feature Integration Theory.

Question 29

What is INATTENTIONAL AMNESIA?

Answer 29

The phenomenon of perceiving something but not remembering it.

Question 30

In Tipper’s experiment looking at green and red known objects, such as trumpet and kite, what did they observe when participants were asked to ignore the green and name the red and the colour of the objects changed between trials? And, what was the name of the phenomenon seen and is this an example of early or late selection?

Answer 30

They found that when the red object was a kite and green object a trumpet on trial one, and then the red object was the trumpet in the next trial participants response time was slower to name the trumpet.
This was interpreted as showing that people perceived and actively ignored the trumpet in the prior trial, which in turn made it more difficult to name it in the following trial. This was termed NEGATIVE PRIMING.
This can be seen as evidence for late selection theory of selective attention.

Question 31

In Duncan’s 1984 experiment that looked at two objects occupying the same space (this time a box with differing height and a gap in the side and a line with sloping one way or the other and either dotted or dashed), what did they find when participants were asked to identify two aspects of the objects when they were of the same object and what did this mean for object-based theories of attention?

Answer 31

They found that when asked to identify two aspects of the same object participants were more accurate at identifying the two aspects when they belonged to the same object.
This was taken as evidence for the object-based theory of attention.
Even though the two objects occupied the same space when participants only had to allocate attention to one object they had more capacity to attend to just that object - which led to increased accuracy.

Question 32

In the experiment done by Egly et al. (1994) that looked at cuing effects from an object-based theory of attention, what did they find when the target was not at the same location as the cue, but on the same object and when the target was on a different object than the cue object, but the same distance from the cue as when the target was on the object, but not at the cue location?
What did this mean for object-based theories of attention?

Answer 32

They found for target being at cue location had fastest RTs.
Target on same object, but not at cue location still had faster RTs than when target was same distance from cue, but on a different object.
This was used as evidence for object based attention.
This was termed a SAME OBJECT ADVANTAGE.

Question 33

Moore et al. (1998) looked at a variation of Egly et al. (!994), where they looked at cuing effects and object-based attention where they had two rectangles occluded by another horizontal bar - which was set up to looked like it was sitting atop the other rectangles.
Did they find same-object cuing effects still?

Answer 33

Yes.

Question 34

What was some early neuroscience findings, based on fMRI, that suggest object-based mechanism of attention?

Answer 34

Parrahippocampal Place area.
Fusifrom Face Area.

Question 35

What is VISUAL NEGLECT?

Answer 35

Selective Deficit of Vision - however, is more an object-neglect condition.

Question 36

Damage to which side of the parietal lobes is generally associated with VISUAL NEGLECT?

Answer 36

The right parietal lobe.
Right parietal lobe damage manifests as a deficit of left visual field processing into conscious awareness.
Not a type of blindness - it is a deficit to attentional field - attention can be cued to that side of the visual field.

Question 37

Is the PARIETAL LOBE associated with the where or what pathway?

Answer 37

Parietal lobe is associated with where pathway.

Question 38

Is the TEMPORAL LOBE associated with the where or what pathway?

Answer 38

Temporal lobe is associated with the what pathway.

Question 39

Posner did an experiment to determine whether Visual Neglect was a visual space-based deficit or an attention-based deficit.
By using participants as their own controls, what did he find when the left visual field was had a valid cue for the target?
What did he find when the target in the left visual field was invalidly cued in the right visual field?

Answer 39

He found that participants performed similarly for left and right visual field for validly cued targets.

He found that participants were worse than when invalid cue was in the right visual field and target in the left visual field.

This suggested that visual neglect was not a visual deficit, but rather an attentional deficit for one side of the visual field.

Question 40

When it comes to VISUAL NEGLECT, what does EXTINCTION refer to?

Answer 40

EXTINCTION refers to the phenomenon seen in people with visual neglect, where when asked to identify an object, such as an apple (even if it is in the left visual field) then they are able to, but when they are presented with another object (in right visual field) they are then not able to “see” or attend to the object in the left visual field.
This suggests that what is happening is some form of competition between attention of the two visual fields.
Similar to auditory tasks performed by Moray involving binaural and dichotic listening.

Question 41

What is SIMULTANAGNOSIA?

Answer 41

Inability to focus on more than one object at a time.

Question 42

What is BALINT’S SYNDROME?

Answer 42

A condition made up of a combination of a triad of optical ataxia, simultanagnosia, and oculormotor apraxia.
People with this condition tend perceive illusory conjunctions. So, they may perceive the colour of one object and the shape of another, and then report having seen one object made of a combination of the features of the multiple objects perceived.

Question 43

Previously we have discussed inhibition of return as pertaining to spacial locations, however, it appears that it is perhaps also (or solely) an object-based phenomenon as well, and more so for some people with conditions such as visual neglect.

Answer 43

Yes.

Question 44

In 1991, did Tipper show that Inhibition of Return was object-based, as opposed to (just) spaced-based?

Answer 44

Yes.
Tipper did an experiment using circles. One flashed and then they both moved clockwise 90 degrees (movement shown on screen) and then the target was shown in the cued or uncued circled. What they found was tha MRT for valid cues were longer than for invalid cues when the SOA was over 300ms. I.e. inhibition of return was based on the object, not the location in space.

Question 45

In 1994, Behrmann and Tipper wanted to see whether visual neglect was space-based or object based.
In their study they had circles connected with a barbell. They presented this to participants and then rotated the barbell and cirlces 180 degrees, such that the circle that was on the left was now on the right.
When they presented a target before rotation and after what did they find and what did this mean for our understanding of neglect?

Answer 45

Prior to rotation when the target was presented RTs were longer when presented in the left circle (consistent with visual neglect of the left visual field with right parietal lobe damage).
After rotation, RTs were longer when the target was presented in the RIGHT circle (inconsistent with neglect of the left visual field, BUT consistent with neglect of the left side of an object).
This was evidence that visual neglect is OBJECT-BASED.
When the barbell was removed this did not occur and visual neglect remained in the left visual field.