Exam 2 (Ch 5-8) Flashcards
Define: Sensation
The processing of basic info from the external world by the sensory receptors in the sense organs and brain.
Define: Brain
The process of organizing and interpreting sensory info about the objects, events, and spatial layout of our surrounding world.
What are 2 ways of studying visual perception?
- Preferential-looking Technique
2. Habituation
Define: Preferential-Looking Technique
- Show infants 2 patterns or 2 objects at a time to see if the infants have a preference for one over the other
- a technique to study visual perception/visual acquity
Define: Habituation
- Repeatedly presenting an infant with a given stimulus until the response declines
- *if infant’s response increases when a novel stimulus is presented, the researcher infers that the baby can discriminate between the old and new stimuli
- a technique to study visual percerption
Why do infants prefer to look at patterns of high visual contrast?
Because infants have poor contrast sensitivity due to the different cone size, shape, and spacing in the eye that infants have from adults (infant cones only catch 2% of incoming light while adults’ catch 65%)
Define: Contrast Sensitivity
The ability to detect differences in light and dark areas in a visual pattern.
Define: Visual Acquity
How well someone can see.
Define: Cones
The light sensitive neurons that are highly concentrated in the fovea
-Role: to process color info and fine detail
Define: Fovea
The central region of the retina
Compare how a 1 month old vs a 2 month old A) visually scans and B) visually tracks an object.
SCANNING:
1 month old: scan perimeters of shapes
2 month old: scans perimeters AND interiors of shapes
TRACKING:
1 and 2 month old: cannot follow object’s path smoothly, is jerky
-it’s not until 3 months of age that infants can track an object SMOOTHLY (no jerky movements)
From birth, infants are drawn to faces. What are some possible explanations for this?
- General bias towards configurations with more elements in the upper half than in the lower half
- By looking at real faces, infant comes to recognize and prefer its own mother’s face after 12 cumulative hours of exposure
- Infant will come to understand the significance of dif facial expressions
How are infants affected by attractive faces?
- Infants will look at faces seen as more attractive for longer
- Infants interact more positively with people with attractive faces
Define: Subjective Contour
Visual illusion that evoke the perception of an edge without the aid of a luminance or color change across the edge.
Define: Perceptual Constancy/Size Constancy
The perception of objects being of constant size, shape, color, etc., in spite of physical differences in the retinal image of the object
-present in both infants and adults
What is the empiricists’ stance on the origin of perceptual constancy?
It develops as a function of experience.
What is the nativists’ stance on the origin of perceptual constancy?
It comes from the inherent properties of the nervous system.
How could you determine if an infant had mastered perceptual/size constancy?
If, when the infant is present with 2 cubes at different distances with the larger cube being farther away, infant will stare longer at the larger cube farther away.
How do infants segregate objects compared to adults?
Infants: use COMMON movement to perceive object segregation (ex. if two separate objects move together at the same time, velocity, and direction, infant will perceive these 2 objects as being 1 whole)
Adults: use general knowledge about the world to perceive object segregation
Define: Optical Expansion
A depth cue in which an object blocks increasingly more of the background–>indicating that the object is approaching.
Define: Binocular Disparity
Difference in object location seen by the right vs the left eye.
-Used by the brain to calculate depth information regarding the object.
Define: Stereopsis
-When does this develop in infants?
Brain’s process for calculating the degree of disparity between the eyes’ differing neural signals and produces the perception of depth.
-Emerges suddenly at 4 months
Define: Object Segregation
The ability to identify separate objects within a visual array.
Define: Monocular Cues
-When does this develop in infants?
A depth cue that needs only 1 eye to be perceived.
-Develops at 6-7 months
Define: Pictorial Cues
-When does this develop in infants?
- Used to portray depth in pictures/paintings
- Also only needs 1 eye to be perceived
-Develops at 6-7 months
Up until what age do children continue to treat pictures (2D objects) as though they were real objects (3D objects)?
19 months.
Define: Auditory Localization
Perception of the location in space of a sound source
-Newborns already have this skill–will turn head towards source of sound
When does the sensitivity to taste and smell develop?
Develops before birth.
Define: Intermodal Perception
The combining of info from 2 or more sensory systems.
-Present from very early in life
Define: Neonatal Reflexes
Tightly organized patterns of action present in a newborn
Give 5 examples of neonatal reflexes.
- Grasping: closing fingers around anything that presses against the palm of their hand
- Rooting: turning their head in the direction of touch and opening their mouth.
- Sucking: set off by contact with nipple
- Swallowing: triggered by sucking
- Tonic Neck: when head turns/is turned to one side, the arm on that side of the body extends while the arm and knee on the other side flex (i.e. baby is trying to get/keep its hand in view)
Define: Stepping Reflex
Infant lifts first 1 leg and then the other in a coordinated pattern resembling walking
When/why does the stepping reflex disappear?
When: 2 months old
Why: Infants’ rapid weight gain in the first few weeks after birth causes their legs to get heavier faster than they get stronger
What was Gesell and McGraw’s theory on the factor that governed motor development.
-Motor development depended on the rate of maturation of the neural cortex.
What are the current theories on the factors that govern motor development?
-Combination of many factors including neural mechanisms, increase in strength, posture, control, balance, perceptual skill, and motivation.
Define: Prereaching Movements
Clumsy swiping movements by young infants toward the general vicinity of objects they see.
-Goes away at around 3-4 months when they begin to successfully reach objects
What is a child’s reaching ability at….
- 3 months
- 7 months
- 10 months
- 3 months: can successfully grab objects
- 7 months: can sit independently which makes reaching quite stable
- 10 months: approach to object is dependent on what they intend to do with the object
What did Karen Adolph discover about infant locomotion and slopes?
Infants do not transfer what they learned about crawling down slopes to how to walk down them.
What is a child’s locomotive ability at…
- 8 months
- 13 months
- 8 months: can crawl (Self-Locomotion)
- 13 months: can walk independently
Define: Self-Locomotion
Ability to move around in the environment on your own.
Define: Scale Errors
Attempt to perform an action with a miniature replica object that is much too small for the action to be completed.
- Due to a failure to integrate visual info represented in 2 dif areas of the brain in the service of action
- Incidence of scale errors decrease as we grow older
Parents keep putting babies on their backs to sleep to reduce the risk of SIDS but now babies are less likely to roll over on time (in terms of developmental milestones). Why could this be?
- Less motivation to roll over b/c better view from their backs
- Less time spent on tummies results in slower development of arm strength
Describe the Visual Cliff Research Study. What does the visual cliff research show about development?
Big sheet of plexiglass is put on top of a box. On half the glass, a sheet of checkered print is placed. The same design is placed on box floor and a divider paper is put in the middle of glass–>causes illusion of the edge of a “cliff”.
Task: infant must cross over the drop area to its mother
Result: infants would not pass the deep side of the cliff
Conclusion:Interdependence of dif domains of development
-Infant perceives and understands the significance of the depth cue of relative size (cliff’s drop)
Define: Social Referencing
The use of another’s emotional reaction to interpret an ambiguous situation
-Appears to be important in infant’s development of wariness of heights
Define: Habituation
A decrease in responsiveness to repeated stimulation
-reveals that learning has occurred
What is the speed of infant habituation indicative of?
Reflects the general efficiency of the infant’s processing of info (i.e. general cognitive ability)
Define: Differentiation
The extraction of stable/invariant elements from the constantly changing stimulation/events in the environment
ex. association b/w voice tone and facial expression
Define: Affordances
Possibilities for actions offered by objects and situations.
ex. light objects can be picked up easier than heavy objects
Define: Statistical Learning
Picking up info from the environment, forming associations among stimuli that occur in a statistically predictable pattern
Define: Classical Conditioning
Form of learning consisting of associations between an initially neutral stimulus with a stimulus that always evokes a reflexive response
-plays a role in infant’s everyday learning about the relations between environmental events that have relevance for them
What are the 4 components of classical conditioning?
- Unconditioned stimulus (UCS)
- Unconditioned response (UCR)
- Conditioned stimulus (CS)
- Conditioned response (CR)
Define: Unconditioned stimulus (UCS)
A stimulus that evokes a reflexive response