Physical and Perceptual Development (copy)

the process by which sensory information is transmitted

sensation

• vision (sight) (seeing an image)

• audition (sound)

What are examples of sensation?

perception

interpretation of sensory input, more complex

• interpretation of visual information (perception of objects as separate; perception of objects as near vs far)

• interpretation of auditory information (perception of the sound of the voice as mom’s voice)

  ex. perceiving the image and thinking about it; knowing it is a notebook and pen on top of a table

What are examples of perception?

perceiving objects as separate, objects as near vs far

What is an example of interpreting visual information?

perception of the sound of the voice as mom’s voice

What is an example of interpreting auditory information?

preference technique, habituation technique

What are two methods for studying perceptual development?

preference technique

present the baby with two different stimuli at the same time

color perception

• present two stimuli (a red circle and a blue circle)

• measure infant looking time (at each circle)

  *If infants spend more time looking at one stimulus, it means they can distinguish two stimuli and prefer one over the other.

  (ex. If infants spend more time looking at the blue circle, it means they can distinguish blue vs red and prefer blue over red)

What is an example of preference technique?

• shows if they can distinguish the two stimuli

  and

• which stimulus they prefer

What does the preference technique tell us about the two presented stimuli?

habituation technique

Depends upon infants’ ability to habituate (means that once they are exposed to a stimuli they will get “used to it” (bored with it) and then seek out something new to focus on/learn about

color perception

• present one stimulus (blue circle)

• habituate infant to stimulus - present a blue circle long enough that the infant looks away from it (meaning the baby has habituated to it)

• present a second stimulus (ex. red circle) and note looking time

• If an infant spends time looking at/focusing on the red circle rather than the blue circle it means that the baby can tell the difference between the two - the baby is interpreting the second stimulus (red circle) as something new/different compared to the first (blue circle)

What is an example of the habituation technique?

• shows that the baby is able to habituate

• the baby is interpreting the two stimuli as different things

What does the habituation technique tell us about the baby?

• measure changes in heart rate (indicates a change in attention)

• measure brain waves (EEG)

• conduct PET scan to visualize activity in different parts of the brain

What are some examples of physiological techniques?

• infants are born extremely nearsighted (20/500)

• can only see objects clearly that are within 12 inches from their faces

• everything else they see is blurry/indistinct

Describe the visual acuity of infants.

• they scan the visual field looking for objects

• track slowly moving objects (ex. moving something across the baby’s face - their eyes will follow it)

How do infant explore visually?

limited

Infants have ________ color vision when compared to adults.

about 4 months

At what age is color vision “normal” (like adult vision) for infants?

Newborns may be able to discriminate very different colors (ex. Red vs yellow) but have difficulty distinguishing more similar colors (ex. Blue vs grey)

Provide an example of how newborns are able to distinguish colors and their limits.

• measured looking time (preference technique)

• the infants preferred faces, objects with patterns, and colors

What did the Fanz study measure and reveal about infants’ object perception?

• light/dark contrast (contrast sensitivity ex. yo gabba gabba characters)

• moving objects

• objects with contours (bold outlines)

Besides faces, objects with patterns, and colors, what else do babies preferred?

equally

Newborn babies seem to be _______ attracted to regularly configured faces and scrambled faces.

Faces have patterns and a dark/light contrast.

Why do babies like about faces?

They are responding to her unique hairline. (vs. unique features

Why do newborns prefer their mother’s face?

about 2 months

Around what age do infants prefer normally configured faces and can distinguish the faces of strangers? (differentiate unique facial features)

about 2 months

Around what age can infants coordinate the sight of their mother’s face with the sounds of her voice?

about 6 months

Around what age can infants recognize faces as the same regardless of facial expression?

the first way babies distinguish objects

• uses movement and habituation

What is object segregation/object unity?

• movement

• static features of objects

What are cues for perception of object segregation?

• marker in front of a folder

• the marker is moved across the folder; the marker moves, folder stays in place

• If the baby can recognize that the marker is separate from the folder, then it has object segregation.

• this example shows the cue of movement

What is an example of object segregation?

• 2 months

• marker moving on a folder, the baby recognizes this

At what age can babies use movement to perceive objects as separate? Give an example.

• about 6-8 months

• marker in front of folder, marker is a different color, shape, texture, so the baby knows it is separate from the folder

At what age can babies use static features of objects to perceive them as separate? Give an example.

depth perception

the ability to perceive the world in 3 dimensions (to perceive objects as closer or farther apart (two eyes)

binocular and monocular depth cues

What two cues do we need to perceive depth?

binocular cues

depth cues that result from two eyes (Ex. retinal disparity: farther away things appear closer together, whereas closer things look farther apart)

involves the ability of both eyes; explains how both eyes work together to show that farther away things appear closer together, whereas closer things look farther apart

What is retinal disparity?

• baby is put on a patterned floor with glass on one side

• result was most babies would not come over onto the glass; they would crawl to the ‘edge’ and stop

• Showed that babies at that age could perceive depth

Explain the ‘visual cliff’ study (Gibson and Walk)

optical expansion

uses kinetic (motion) cues to perceive depth

• think objects expanding on the retina

ex. study where an object moved closer and closer to the baby

• baby would react as the object got closer if they have optical expansion (blinking, grabbing/defensive reaction (dependent on age))

• Can detect differences between deep and shallow sides of the visual cliff (HR changes)

• Blink and/or respond defensively to looming objects

• Using kinetic/motion cues for depth - also called “optical expansion”

Depth Perception Milestones: What can the baby do at 1-3 months?

Binocular perception - retinal disparity (blending of 2 images, 1 from each eye; we register differences between two images and this provides cues about depth)

Depth Perception Milestones: What can the baby do at 4-5 months?

• Use of monocular/pictorial depth cues (ex. Overlap, relative size, linear perspective, etc.)

• Babies are perceiving depth in the same way adults are

Depth Perception Milestones: What can the baby do at 6-7 months?

Boats - the yellow one is larger so we perceive it as closer; the green boat appears farther away and looks higher in the visual field

What is an example of relative size and height?

• relative size and height

• linear perspective

• interposition

What are the three monocular/pictorial depth cues?

relative height and size

monocular/pictorial depths: larger objects are perceived as being closer, objects that are smaller and higher in the visual field are perceived as being farther away

linear perspective

monocular/pictorial depths: parallel lines look like they converge in the distance (converge = farther away, not converging = closer)

interposition

monocular/pictorial depths: overlapping

Blue circle overlaps red circle so blue circle appears to be closer to us than the red circle

What is an example of interposition?

about 3 months

At what age can babies discriminate between mom and dad’s voice? (voice discrimination)

yes, unlike their sight

Can newborns hear well?

high-pitched sounds with rising/falling intonation

What type of sounds to babies prefer?

motherese

the way adults talk to babies (babies like the high pitched childish sounding voice)

• put things on the walls that have patterns

• pictures of animals (because babies like faces)

• large and prominent pictures (because babies are very near-sighted)

• bright, contrasting colors (dark and light areas, primary colors)

• mobile (movement, music, color, close the baby)

• toys that make noise or ones that have faces

• black and white toys (for the color contrast)

What design choices would you make to maximize stimulation in an infant nursery? (possible exam question)

skip

Although there is a predictable sequence of motor developments (ex. roll over, sit up, crawl), the sequence is generally followed and some babies _____ a step.

normative

There is a range of _________ development for each step of motor development (ex. walking at 11-15 months, average is 12 months for first unassisted steps)

equally important

Is nature or nurture more important, or are they equally important for motor development?

prone, lift head

At ½ month, what can a baby do?

prone, chest up, use arms for support

At 2-4 months, what can a baby do?

support some weight with legs

At 2-5 months, what can a baby do?

sit without support

At 4.5-8 months, what can a baby do?

pull self to stand

At 5-10 months, what can a baby do?

walk using furniture for support

At 7-13 months, what can a baby do?

stand alone easily

At 10-14 months, what can a baby do?

walk alone easily

At 11-14 months, what can a baby do?