Perception 3,6

Question 1

Movement and perception

Answer 1

movement adds a complexity to perception that isn’t there when we are sitting in one place, movement also helps us perceive objects in the environment more accurately.

Question 2

How does movement increase perception accuracy

Answer 2

moving reveals aspects of objects that are not apparent from a single viewpoint.

Question 3

Diagram 3.29

Answer 3

From the first viewpoint, you may not directly recognize it, but walking around the statue and looking at it from different viewpoints doesn’t leave any doubt that you are actually looking at Michelangelo’s famous sculpture of David. Thus, seeing an object from different viewpoints provides added information that results in more accurate perception, and this may hold even more for objects that are less common.

Question 4

How is movement also importnat?

e.g coffee

Answer 4

of the coordination that is continually occurring between perceiving stimuli and taking action toward these stimuli.

e.g

pick up a cup of coffee (Figure 3.30). You first identify the coffee cup among the flowers and other objects on the table (Figure 3.30a). Once the coffee cup is perceived, you reach for it, taking into account its location on the table (Figure 3.30b). As you reach, avoiding the flowers, you position your fingers to grasp the cup, taking into account the perception of the cup’s handle (Figure 3.30c); then you lift the cup with just the right amount of force, taking into account your estimate of how heavy it is based on your perception of its fullness.

Question 5

Extra Information fo coffee

Answer 5

This simple action requires continually perceiving the position of the cup, and of your hand and fingers relative to the cup, while calibrating your actions in order to accurately grasp the cup and then pick it up without spilling any coffee (Goodale, 2010

Question 6

Link between perception and action have been clearer as result of

Answer 6

physiological research that began in the 1980s

Question 7

What did resrarch suggested in the 1980s

Answer 7

two processing streams in the brain—one involved with perceiving objects, and the other involved with locating and taking action toward these objects.

This physiological research involves two methods: brain lesioning—the study of the effect of removing parts of the brain in animals, and neuropsychology—the study of the behaviour of people with brain damage, which we described in Chapter 2

Both of these methods demonstrate how studying the functioning of animals and humans with brain damage can reveal important principles about the functioning of the normal (intact) brain.

Question 8

Classical experiment by Underleider and Mishkin studied what?

Answer 8

how removing a part of a monkey’s brain affected its ability to identify an object and to determine the object’s location. This experiment used a technique called brain lesioning—removing part of the brain.

Question 9

What is brain lesioning?

Answer 9

Removing part of the brain.

Question 10

What is the goal of brain lesioning experiment?

Answer 10

determine the function of a particular area of the brain.

Question 11

How is determining function of particular function of brain using brain lesioning experiment?

Answer 11

by first determining an animal’s capacity by testing it behaviourally.

Question 12

Why do most leison experiments studying perception use monkeys?

Answer 12

because of the similarity of the monkey’s visual system to that of humans and because monkeys can be trained to demonstrate perceptual capacities such as acuity, colour vision, depth perception and object perception.

Question 13

What happens once animal’s perception has been measured?

Answer 13

a particular area of the brain is removed or destroyed, either by surgery or by injecting a chemical in the area to be removed.

deally, one particular area or structure is removed and the rest of the brain remains intact.

Question 14

What happens after particular area is removed?

Answer 14

the monkey is tested to determine which perceptual capacities remain and which have been affected by the lesion.

Question 15

Comparing brain leisoning with neuropsychology

Answer 15

brain lesioning has the advantage that you can take pre- and post-lesion measurements. Indeed, neuropsychological patients are typically examined only after brain damage has occurred. Another obvious advantage is that there is much more control over which exact areas are destroyed

Question 16

Ungerleider and Mishkin presented monkeys with two tasks:

Answer 16

(1)

an object discrimination problem, and

(2)

a landmark discrimination problem.

Question 17

What happened in object discrimination prbolem?

Answer 17

monkey was shown one object, such as a pyramid, and was then presented with a two-choice task like the one shown in Figure 3.31a, which included the “target” object (the pyramid) and another stimulus, such as the cube. If the monkey pushed aside the target object, it received the food reward that was hidden in a well under the object.

Question 18

What happened in landmark discrmination problem?

Answer 18

Here, the cone is the landmark, which indicates the food well that contains food. The monkey received food if it removed the food well cover closer to the cone.

Question 19

Definition of object discrimination problem?

Answer 19

A problem in which the task is to remember an object based on its shape and choose it when presented with another object after a delay. Associated with research on the what processing stream.

Question 20

Definition of landmark discrimination problem

Answer 20

Problem in which the task is to remember an object’s location and to choose that location after a delay. Associated with research on the where processing stream.

Question 21

Diagram of Ungerleider and Mishkin.

Answer 21

Question 22

What happened during the lesion part of the experiment?

Answer 22

part of the temporal lobe was removed in some monkeys.

Question 23

What happened after testing leisoning

behaviouraltesting

Answer 23

object discrimination problem became very difficult for the monkeys when their temporal lobes were removed. This result indicates that the neural pathway that reaches the temporal lobes is responsible for determining an object’s identity. Ungerleider and Mishkin therefore called the pathway leading from the striate cortex to the temporal lobe the what pathway (Figure 3.32).

Question 24

Definition of what pathway

Answer 24

Neural pathway, extending from the occipital lobe to the temporal lobe, that is associated with perceiving or recognizing objects. Corresponds to the perception pathway.

Question 25

What happened when other monkeys got their parietal lobes removed?

Answer 25

had difficulty solving the landmark discrimination problem. This result indicates that the pathway that leads to the parietal lobe is responsible for determining an object’s location. Ungerleider and Mishkin therefore called the pathway leading from the striate cortex to the parietal lobe the where pathway (Figure 3.32).

Question 26

Definition of where pathway

Answer 26

Neural pathway, extending from the occipital lobe to the parietal lobe, that is associated with neural processing that occurs when people locate objects in space. Roughly corresponds to the action pathway.

Question 27

Applying idea of what and where pathway

e.g person picking up cup of coffee

Answer 27

the what pathway would be involved in the initial perception of the cup and the where pathway in determining its location—important information if we are going to carry out the action of reaching for the cup.

Interestingly, it has been suggested that these pathways can operate quite independently from each other, meaning, for example, that you do not necessarily have to recognize the cup in order to reach for it and to pick it up (Goodale, 2014).

Question 28

What did Milner and Goodale used neurophysical approach to reveal two streams called what?

Answer 28

one involving the temporal lobe (ventral stream) and the other involving the parietal lobe (dorsal stream).

Question 29

What is neuropsychological approach?

Answer 29

one involving the temporal lobe (ventral stream) and the other involving the parietal lobe (dorsal stream).

Question 30

How did Milner and Goodale (1995) reveal two streams?

Answer 30

researchers studied D.F., a 34-year-old woman who suffered damage to her temporal lobe from carbon monoxide poisoning caused by a gas leak in her home. As a result, she developed visual agnosia, meaning that she no longer could recognize everyday objects, familiar faces and geometrical shapes, despite being able to identify an object’s colour or visual texture.

On the other hand, D.F. had no difficulty guiding her hand movements to reach for something and to pick it up. These observations provided additional hints that vision-for-action may not depend on the same mechanism as vision-for-perception (Goodale, 2014)

Question 31

Definition of visual agnosia

Answer 31

Inability to recognize everyday objects, familiar faces and geometrical shapes.

Question 32

Procedure of D.F

Answer 32

D.F. was asked to rotate a card held in her hand to match different orientations of a slot (Figure 3.33a). She was unable to do this, as shown in the left circle in Figure 3.33b. Each line in the circle indicates how D.F. adjusted the card’s orientation. Perfect matching performance would be indicated by a vertical line for each trial, but D.F.’s responses are widely scattered. The right circle shows the accurate performance of the normal controls

Question 33

Fidnings of D.F

Answer 33

D.F. had trouble rotating a card to match the orientation of the slot, it would seem reasonable that she would also have trouble placing the card through the slot because to do this she would have to turn the card so that it was lined up with the slot

D.F. was asked to “mail” the card through the slot (Figure 3.34a), she could do it, as indicated by the results in Figure 3.34b. Even though D.F. could not turn the card to match the slot’s orientation, once she started moving the card toward the slot, she was able to rotate it to match the orientation of the slot. Thus, D.F. performed poorly in the static orientation matching task but did well as soon as action was involved (Murphy, Racicot & Goodale, 1996).

Question 34

Conclusion of D.F study

Answer 34

Milner and Goodale (1995) interpreted D.F.’s behaviour as showing evidence that there is one mechanism for judging orientation and another for coordinating vision and action.

Question 35

What did Milner and Goodale suggest from experiment?

Answer 35

pathway from the visual cortex to the temporal lobe (which was damaged in D.F.’s brain) be called the perception pathway and the pathway from the visual cortex to the parietal lobe (which was intact in D.F.’s brain) be called the action pathway.

he perception pathway corresponds to the what pathway we described in conjunction with the monkey experiments, and the action pathway corresponds to the where pathway. Thus, some researchers refer to what and where pathways and some to perception and action pathways. Whatever the terminology, the research shows that perception and action are processed in two separate pathways in the brain.

Question 36

Ebbginhaus illusion

Answer 36

Unlike in the previous studies, participants in these experiments were healthy individuals with no brain damage. Aglioti, DeSouza and Goodale (1995) were among the first to demonstrate that while participants experienced a strong perceptual illusion of size for the central circle of the classic Ebbinghaus illusion (i.e., judging the central circle to be smaller compared to its actual size when surrounded by bigger circles and vice versa, see Figure 3.35), their anticipatory grip aperture (the opening between thumb and index finger) was not affected by this illusion when they were asked to pick up the central disc in a 3D version of this illusion. In other words, while participants’ object perception was misled by the size of the surrounding circles, their vision-for-action system was not.

Question 37

In monkeys, the “what”, or perception, pathway extends from the occipital lobe to the _____ lobe and the “where”, or action, pathway extends from the occipital lobe to the _____ lobe.

Answer 37

temporal; parietal

In monkeys, the “what”, or perception, pathway from the occipital lobe to the temporal lobe and the “where”, or action, pathway from the occipital lobe to the parietal lobe.

Question 38

Julia hears someone call her name and turns towards the sound. Julia has just used, in order, her _____ and _____ auditory pathways.

Answer 38

what; where’

Hearing a sound and identifying it as your name involves the what pathway while turning towards the direction of the sound involves the where pathway.

Question 39

Ungerleider and Mishkin surgically removed the _____ of monkeys and found that the monkeys had a great deal of difficulty performing a discrimination task.

Answer 39

Ungerleider and Mishkin surgically ablated the temporal lobe of monkeys and found that the monkeys had a great deal of difficulty performing a discrimination task, indicating that the neural pathway that reaches the temporal lobes is responsible for determining an object’s identity.