Lecture 3: Perception Motor Flashcards
What is Sensation?
sensory receptor neurons detect information and transmit it to the brain
What is Perception?
the psychological process of
organizing and interpreting sensory input
What Is Gestalt theory of perception?
Principles or laws of human perception that describe humans’ spontaneous and natural organization of visual stimuli into meaningful
patterns, such as perceiving objects as whole
What is Ecological theory of perception?
Eleanor and James Gibson - highlights the evolutionary foundations of perception and
connections between perception and action
What is Affordances for Action?
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
How do we test infants?
- Preferential-looking tests
- Habituation-recovery tests
- Contingent reinforcement studies
What is Preferential Looking?
When 2 stimuli’s are present to measure attention to both
– If infant pays more attention to one stimulus, s/he:
* Notices the difference
* “Prefers” one stimulus over the other
What is Habituation-Recovery?
When 1 stimulus is presented until infant becomes “bored”
– Present new stimulus
– If infant pays more attention to the new stimulus, s/he:
* Notices the difference
How can we measure attention?
– Overt behaviour
– Physiological measures
What is Contingent-Reinforcement Studies?
- 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
What is the most studied behaviour in infant perception?
Infant vision
What does infant vision include?
– actively looking
– tracking objects and people
– recognizing familiar, loved faces
What is Visual acuity?
How sharp is a babies’ vision?
By what age do children see 20/20 vision
Age 6
How do developmental scientists test infant visual acuity?
A slightly modified preferential-looking experiment offers one approach. For example, researchers present infants with two screens, one containing a solid gray panel and the other a panel of black and white stripes. When the black and white stripes move progressively closer together, the stripes blend visually until the striped panel resembles the gray panel (black and white blend to make gray)
What is Tracking motion?
Newborns move their heads in response to moving stimuli
– Jerky eye movements until 2 months of age, with further
development through 4 or 5 months
What is a Good continuation?
A Gestalt principle of organization that claims a
natural tendency for individuals to view objects or
stimuli as continuous or whole
What is anticipatory eye
movement?
shifting the eyes before something occurs, as though predicting what will happen next— starts around 6 months of age
Depth and distance are signaled by cues from what?
two eyes—binocular cues, and also from one eye—monocular cues.
What are binocular cues
Binocular cues arise because the two eyes have different views of the world and thus send different signals to the brain.
What are monocular cues
Monocular cues also provide information about depth and distance through information about visual angles: Distant objects produce smaller angles and smaller objects on the retina relative to close objects.
What is Perceptual narrowing?
A developmental process characterized by a diminished ability to distinguish among less frequently-encountered stimuli
How can we explain an infants early tendency to look at faces?
Infants’ early tendency to look at faces may be explained by a bias to look at things that contain a density of features in the top half. When researchers compared newborns’ looking to faces configured in different ways, babies spent more time looking at upright than upside down faces
What can the fetus hear everything clearly?
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
What is Absolute threshold?
minimum sound level of stimulus to detect a sound
What is Relative threshold?
minimum difference in loudness or pitch to discriminate between sounds
Do newborns prefer hearing speech more than non-speech sounds?
YES!
– Mother’s voice over stranger’s voice
– “Baby talk” over adult-directed speech
– Native language over different languages
What is Perceptual narrowing?
By 4 months, infants prefer music of their own culture;
by 12 months, difficulty discriminating rhythmic
structures of other cultures
What do newborns think about music?
Newborn brains respond to variations in music (pitch,
pitch changes, rhythm)
Who is William Thierry Preyer?
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
What is Gessell & Motor Milestones?
American child psychologist who tracked the motor behaviors and physical growth of 107 infants between 4 to 56
weeks
What is Maturation?
Maturation is a genetically determined process that
controls and preserves the order of behaviors and
skills as children develop
What did Gesell base his claims of maturation on?
Gesell based claims of maturation on “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
Who is Myrtle McGraw and Motor Practice?
McGraw engaged in a controversial and highly provocative study with twin boys, Johnny and Jimmy, decades before universities established ethical guidelines for human research. Trained one twin on specific
skills, while the other twin in
crib
– Trained twin showed early
performance on specific
motor skills that were
trained, but not on those
untrained
Who is Esther Thelen & Dynamic Systems?
American psychologist Esther Thelen; Dynamic systems: considers the many interacting forces that influence infants’ motor
skills, beyond “top-down” brain explanations
What is Newborn stepping?
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
What is Posture?
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)
When and how do infants sit?
In North America, infants begin to sit independently around 5-7 months, in order to sit they must maintain posture, and they accumulate hours of practice with various types of supported sitting—being held in their caregivers’ arms, propped up with pillows, and secured in contraptions such as infant seats, swings, car seats, and high chairs.
How do infants stand up during the first 7-13 months?
infants use furniture and other
supports to pull up to a standing position and then
“cruise” sideways while holding on
When does an infant walk independently?
at 1 years old
What is Maturational Viewpoint?
Unfolding of a genetically programmed series of events
What is Experiential Viewpoint?
Opportunities to practice are important
What is the back to sleep campaign?
The Back to Sleep campaign (now called the Safe to Sleep campaign), implemented in 1994, to prevents SIDS
What is SIDS?
sudden infant death syndrome
How does the role of experience differ for each child?
Infants growing up in different parts of the world are
exposed to different opportunities to practice such
motor skills as sitting and walking
