Lecture 3 Perceptual and Motor Development

Question 1

what is Sensation?

Answer 1

sensory receptor neurons detect
information and transmit it to the brain

begins when a stimulus in the environment
activates receptors in the sensory organs (eyes, ears, nose, mouth,
and skin). Receptors are neurons that convert the stimulus into
signals that are sent to the brain. For example, light activates
electromagnetic receptors in the eyes that then transmit information
to the brain about the visible environment. Similarly, airborne
molecules activate chemoreceptors in the nose that signal about
odors

Question 2

what is Perception?

Answer 2

the psychological process of
organizing and interpreting sensory input

Infants’ sensory organs enable them to detect
and discriminate among the sights, sounds, tastes, smells, and
touches of their environments. Infants then organize and interpret
sensory information in the process of perception.

Question 3

what are two early theories

Answer 3

1. Gestalt theory of perception
2. Ecological theory of perception

Question 4

what is gestalts theory of perseception?

Answer 4

principles or laws of human perception that describe humans spontaneous and natural organziation of visual stimuli into meaningful patters such as perceiving objects as whole

Question 5

what is the ecolgical theroy of perception?

Answer 5

elenor and Jame gibson highligh the evolutionary foundations of perception and connections between perception and action

Question 6

whats the perception-action feedback loop

Answer 6

refers to
the continuous cycle that connects perception and action as people
perceive, act, and adjust their actions in response to an everchanging
environment

A: baby looking, baby reahces
B: bay looking, reaches, touches, grasps and manipulates

(A) Depiction of a simple perceptionaction
feedback loop.

B) An example of a perception-feedback loop in which an infant looks
at a toy, reaches, touches, grasps, and manipulates the toy. The feedback from each step in
the sequence leads to new actions and alters the infant’s perceptions as what the baby
sees and touches continually changes.

Question 7

whats an Affordances for Action

Answer 7

An individual’s interpretation of which actions
are possible, and which are not possible based
on their perceptions
– E.g., When infants determine that a flat surface
offers the opportunity for walking

Question 8

how do we test infants

Answer 8

1. Preferential-looking tests
2. Habituation-recovery tests
3. Contingent reinforcement studies

Question 9

what are Preferential Looking tests

Answer 9

(Fantz, 1960s):
– Present 2 stimuli, measure attention to both
– If infant pays more attention to one stimulus, that means…
she or he:
* Notices the difference
* “Prefers” one stimulus over the other

Question 10

what are Habituation-Recovery tests

Answer 10

– Present 1 stimulus until infant becomes “bored”
– Present new stimulus
– If infant pays more attention to the new stimulus,
s/he:
* Notices the difference

involve presenting infants with a stimulus until they habituate or decrease their attention to the stimulus. When researchers then present infants with a new
stimulus, infant attention might recover or rebound to its initial level. Infants’ rebound of attention is thought to offer a window

Question 11

how can we measure attention?

Answer 11

– Overt behaviour
– Physiological measures

Question 12

what are Contingent-Reinforcement Studies

Answer 12

• Operant conditioning
• Infants increase a specific behavior in
  response to certain stimuli to obtain reward
  – E.g., infants’ sucking behaviors in response to
  hearing their mothers’ voice

Researchers test whether
infants increase a specific behavior, such as sucking a pacifier or turning their head, in response to certain stimuli, such as hearing the
mother’s voice. Contingent reinforcement is sometimes used in conjunction with habituation-recovery to examine decreases and
then increases in the rewarded behavior. For example, an infant
might learn to suck on a pacifier to hear music. After some time, the infant habituates to the music and the sucking subsides. At that point, researchers introduce a new stimulus, such as the sound of birds chirping. Infants’ rebound in sucking indicates that they candiscriminate between the old and the new sounds.

Question 13

whats Infant Vision?

Answer 13

• The most studied behavior in infant perception
• Vision is not simply seeing. It includes:
  – actively looking
  – tracking objects and people
  – recognizing familiar, loved faces

Question 14

whats Visual acuity

Answer 14

( the ability to see fine detail)
– How sharp is babies’ vision?

Question 15

explain the time line of The Development of Acuity

Answer 15

• Newborns: 20/600
• Legally blind!
  -They can see objects
  about a foot away best
• By 6 months: 20/100
• By 12 months: 20/50
• By 6 years: 20/20 (adult
  level)

Question 16

whats Tracking motion

Answer 16

neworns moving thier head in respionse to moving stimuli

• Jerky eye movements until 2 months of age, with further
  development through 4 or 5 months
  – Anticipatory eye movements: 6 months
• Facilitates social interactions

Question 17

whats contrast sensitivity

Answer 17

the minimum
difference in brightness between an image and its background that
infants can perceive

Question 18

whats Good continuation:

Answer 18

A Gestalt principle of organization that claims a
natural tendency for individuals to view objects or
stimuli as continuous or whole

• Gestalt psychologists asserted that infants, like adults, perceive a
  coherent visual world, and so will infer for example, that two pieces
  of a rod sticking out from either end of a box in front of the rod form
  a single rod. That’s because infants perceive an object as whole when
  part of the object is occluded (hidden) by another object, what is
  referred to as good continuation.

Question 19

provide a timeline of depth perception

Answer 19

• Kinetic Cues (looming or
  approaching):
  – 1 month of age
• Stereopsis (binocular vision)
  – 4 months of age
• Sensitivity to pictorial
  (monocular) cues
  – 6-7 months of age
  Depth

Question 20

whats Depth perception

Answer 20

refers to the ability to perceive vertical distance
from a top surface or space to a bottom one. (Note: distance refers to
the space between two points, which can be horizontal or vertical).
Without depth and distance perception, we would be unable to move
about without bumping into things or recognize the dangers of a
train platform, balcony, or mountain cliff.

Question 21

whats binocular
cues,

Answer 21

Depth and distance are signaled by cues from two eyes

Question 22

whats monocular cues

Answer 22

Depth and distance are signaled by cues from from one eye

Question 23

what % of Young infants view faces of their
waking time

Answer 23

25-50%

Question 24

new borns perfer..

Answer 24

their mother’s face

Question 25

whats Perceptual narrowing

Answer 25

A developmental process characterized by a diminished ability to distinguish among less frequently-encountered stimuli * Own-species vs. other-species; own-race vs. other-race

Question 26

Contexts of Face Perception in adults

Answer 26

Can distinguish humans but not monkeys

Question 27

Contexts of Face Perception Newborn-6 mths

Answer 27

Can distinguish both humans and monkeys

Question 28

Contexts of Face Perception after-6 mths

Answer 28

Can no longer distinguish between monkeys

Question 29

What can babies perceive?

Answer 29

Audition * Fetuses can hear in the last 3 months before birth * Newborns hear quite well, but: – Sounds must be louder for newborn to hear – Sounds in the range of human voices are heard best

Question 30

whats Absolute threshold:

Answer 30

minimum sound level of stimulus to detect a sound

Question 31

whats Relative threshold

Answer 31

minimum difference in loudness or pitch to discriminate between sounds

Question 32

Do newborns prefer hearing speech more than non-speech sounds?

Answer 32

– YES! – Mother’s voice over stranger’s voice – “Baby talk” over adult-directed speech – Native language over different languages * Their auditory system is biased to attend to a socially significant stimulus!

Question 33

exmpain the biological foundation for music perception

Answer 33

* A biological foundation for music perception – Newborn brains respond to variations in music (pitch, pitch changes, rhythm) – Infants share the strong preferences adults have for some musical sounds over others

Question 34

whats Perceptual narrowing:

Answer 34

a diminished ability to distinguish among stimuli because of a lack of experience with them. Faces associated with a person’s sex and race illustrate the phenomenon of perceptual narrowing.

Question 35

provide a timiline for preceptual narrowing

Answer 35

By 4 months, infants prefer music of their own culture; by 12 months, difficulty discriminating rhythmic structures of other cultures

Question 36

explain the History behind William Thierry Preyer

Answer 36

* English physiologist who systematically documented changes in his own son’s motor skills from birth to 3 years of age * Proposed a common and universal sequence of motor development across species

Question 37

explain History behind Gessell & Motor Milestones

Answer 37

* American child psychologist who tracked the motor behaviors and physical growth of 107 infants between 4 to 56 weeks

Question 38

whats Maturation

Answer 38

Maturation is a genetically determined process that controls and preserves the order of behaviors and skills as children develop

Question 39

Gesell based claims of maturation on....

Answer 39

“co-twin” study on stair climbing in identical twin girls (Gesell & Thompson, 1929) – Trained twin exceeded non-trained twin, but the other twin learned faster and caught up – Claim: when maturationally ready, learning is faster

Question 40

whats Dynamic systems

Answer 40

considers the many interacting forces that influence infants’ motor skills, beyond “top-down” brain explanations - exmaple: the stepping reflex ( a phenomenon in which newborns demonstrate spontaneous, coordinated “stepping” movements by lifting one leg and then the other when held over a surface—presents a starting point for understanding how something as seemingly simple as body weight can affect the expression of a behavior)

Question 41

What is Posture?

Answer 41

* The position in which a person holds their head and body, and ability to stably maintain the body’s position – Stable posture facilitates action – Unstable posture impedes action * Critical to all motor skills (e.g., sitting, reaching, standing)

Question 42

explain sitting

Answer 42

Must maintain posture * Muscles in the neck, torso, legs, and hips to help with balancing (e.g., Adolph & Berger, 2006) * Supported sitting helps promote infants’ later sitting ability * In North America, infants begin to sit independently around 5-7 months

Question 43

Practice with crawling permits infants to..

Answer 43

estimate accurately if different surfaces are safe or risky to crawl across

Question 44

provide a time line for Locomoting: Cruising and Walking

Answer 44

* 7 to 13 months: infants use furniture and other supports to pull up to a standing position and then “cruise” sideways while holding on (Bly, 1994) * Different than walking: Relies on hands for support (no awareness of legs) * 1 year old: infants let go of supports and begin walking independently * With experience, infants gain proficiency in walking (step length, speed, and width)

Question 45

What drives the development of motor abilities?

Answer 45

- Maturational Viewpoint * Unfolding of a genetically programmed series of events – Experiential Viewpoint * Opportunities to practice are important

Question 46

old parenting practices

Answer 46

Parenting practices: – 1992 “Back to Sleep” Campaign to prevent SIDS – This has delayed the onset of rolling over and crawling * Tummy time Infants growing up in different parts of the world are exposed to different opportunities to practice such motor skills as sitting and walking (e.g., Adolph, Karasik, & Tamis-LeMonda, 2010)