Chapter 5: Perceptual Development

Question 1

Using what type of paradigm did scientists find that ___ month olds have size and shape constancies?

Answer 1

Habituation paradigms. Two month olds.

Question 2

Besides demonstrating that sound can be heard prenatally, what broader conclusions do these studies help us draw?

Answer 2

Our gestational experiences influence who we become; we learn in gestation. This is evidence against the learned vs. innate debate, as there is always an environment at the bedrock of experience.

Question 3

What is the function of perception, and does this have any important implications?

Answer 3

“The function of perception is to allows us to behave sensibly in the world with respect to survival and reproductive interests.” This means that perception varies as per each situation. Ex. Hills are perceived as steeper when fatigued.

Question 4

Define the term ‘sleeper effect’, and then provide an example of it.

Answer 4

“A developmental effect that is evident only sometime after exposure to a particular environmental cue.” Children who had bilateral cataracts from one month to a year, and then had it removed, showed significant deficits in the type of skills (holistic processing) that are traditionally developed in early life. Provides evidence into critical periods.

Question 5

Aside from inversion effects, can you provide another piece of evidence that supports the claim that face processing is specialized?

Answer 5

Holistic processing is the idea that we view faces not by their individual features, but as a whole representation. When certain features of a face are swapped out we are slow to notice. This is not true for other objects, such as cars or houses. Hence why this is evidence that our face processing is specialized.

Question 6

What frequency has infant hearing been specialized to detect?

Answer 6

High pitch sounds.

Question 7

In what order (from most to least) are the senses developed when a baby is born?

Answer 7

Touch, hearing, and vision.

Question 8

What do inversion effects and the fusiform gyrus tell us about our cognition?

Answer 8

“This is taken as evidence that faces are processed somehow differently than other objects and that the perceptual mechanisms that process faces are so specialized that they do not work when faces are inverted.”

Question 9

How can you explain an infants interests?

Answer 9

“An infant’s interests are adaptive: Very young infants will orient to social information allowing them to observe just what they need to learn about the world.”

Question 10

When do we see intermodal perception in infants? What did Piaget believe in relation to this?

Answer 10

One month. “He thought the information from different modalities would be separate for at least the first several [five] months after birth.”

Question 11

Explain why infants begin to enjoy salty foods around four months?

Answer 11

This is a preparatory mechanism for when infants are weaned off breast milk at six months.

Question 12

What are three major pieces of evidence against the associationist explanation for visual development?

Answer 12

1) Sleeper effects. 2) Critical periods. 3) Early competencies.

Question 13

Why are sleeper effects interesting to developmental psychologists?

Answer 13

“The sleeper effect clearly shows that early experience can set up or maintain the neural architecture that will underlie some perceptual ability much later.”

Question 14

Why is the visual cliff paradigm interesting? At which age has it demonstrated depth perception in children?

Answer 14

Despite having developed depth perception at a young age, infants do not show a fear response to heights until later in development. As early as one month, but more traditionally, around six months.

Question 15

When do infants develop most of their motion perception abilities?

Answer 15

From two to three months.

Question 16

What is the only sense that infants do not use prenatally? I.e. what sense do we not have evidence for?

Answer 16

Vision.

Question 17

Other than recognizing the existence of ocular dominance columns, what was the major finding within Hubel’s and Weisel’s study?

Answer 17

How nature and nurture work in concord with experience-expectant learning mechanisms. Alongside these mechanisms come critical periods, where developmental input is required for normative progression to occur.

Question 18

How does an infants sucking behaviour change when excited?

Answer 18

The gaps between bursts shorten.

Question 19

Explain the system 1 and system 2 approach to the U-Shaped curve.

Answer 19

At one month of age infants lose their ability to process faces in a specialized manner—a process available at birth. This comes back at the second month and then continues until the fourth. Theorists have described this gap as the switching between systems. System 1 (birth to gap): Orients the baby to things in the environment that are likely to be faces. System 2 (gap to four months): Takes advantages of this visual orientation to build an adult-like face template.

Question 20

How do six and nine month olds differ in the facial processing of alternative species (e.g. monkeys)?

Answer 20

Six month olds can distinguish between members of a primate group with equal proficiency to that of a human group. Nine month olds lose this ability to distinguish amongst members of other species. Importantly, this is entirely based upon experience. Theoretically, a human could lose their ability to distinguish between human faces.

Question 21

What part of the face will a one month old infant look at? How about a two month old infant?

Answer 21

One month: Outer contours of the face. Two months: Internal details of the face.

Question 22

How do we know that infants can understand intonations and stress in their mother’s voice?

Answer 22

“…the fetus’s heart rate changes, indicating interest, when the mother starts to speak” And “…the fetus’s movement patterns can change in response to other external noises”

Question 23

Here are a few visual acuity milestones. Can you plot when they develop? 1) “The development of the visual cortex between the ages of _ and _ months is dramatic.” 2) At this age, the infants acuity is adult-like.

Answer 23

1) Two and three. 2) Five years.

Question 24

What is the Teller acuity card paradigm, and how can we use it to test infant’s vision?

Answer 24

“In this procedure, an experimenter stands behind a wall and watches the infant as the infant is presented with two side-by-side cards. One card shows black and white bars (either horizontal or vertical) and the other is solid grey.” If the experimenter–who is unaware of the card order that he is displaying–can notice a preference in the child then we would describe that child as having acuity at this distance. Can be used to plot visual milestones.

Question 25

Infants of what age demonstrated colour constancy?

Answer 25

Four month olds.

Question 26

Our colour constancy is far from perfect. Can you provide an example where it might be flawed?

Answer 26

When dealing with wave lengths outside of the terrestrial range (ultraviolet or infrared) then we are no longer able to maintain constancy. This is because our EEA did not contain these stimuli, meaning that our ancestors were not able to develop adaptations surrounding them. Ex. Artificial lighting in a parking garage.

Question 27

Infants can discriminate between these colours (1) at birth, yet can only see this other colour (2) at __ months. What are the mentioned colours, and when does the latter develop?

Answer 27

1) Infants can discriminate between red and green colours at birth due to the evolutionary utility it served when distinguishing fruit from foliage. 2) Infants can distinguish amongst shades of blue at four months.