42 terms

Chapter 4 Physical Development in Infancy and Toddlerhood

Skeletal Age
Best way of estimating a child's physical maturity, is to measure this way, it's a measure of bone development
Cephalocaudal Trend
Latin for "head to tail"
Proximodistal Trend
Growth proceeds, literally, from "near to far"--from the center of the body outward
Nerve cells that store and transmit information
Between neurons are tiny gaps where fibers from different neurons come close together but do not touch
Neurons send messages to one another by releasing these chemicals
Synaptic Pruning
Neurons that are seldom stimulated soon lose their synapses, in this process--it returns neurons not needed at the moment to an uncommitted state so they can support future development
Glial Cells
Half of the brain's volume consists of these, which are responsible for myelination
The coating of neural fibers with an insulating fatty sheath that improves the efficiency of message transfer
Cerebral Cortex
Surrounds the rest of the brain, resembling half of a shelled walnut. It is the largest, most complex brain structure--accounting for 85% of the brain's weight and containing the greatest number of neurons and synapses
Frontal Lobes
Responsible for thought, in particular consciousness, inhibition of impulses, integration of information, use of memory, reasoning, planning, and problem-solving strategies
Specialization of the two hemispheres
Brain Plasticity
A highly plastic cerebral cortex, in which many areas are not yet committed to specific functions, has a high capacity for learning. And if a part of the cortex is damaged, other parts can take over tasks it would have handled
Experience-expectant brain growth
The young brain's rapidly developing organization, which depends on ordinary experiences--opportunities to see and touch objects, to hear language and other sounds, and to move about and explore the environment
Experience-dependent brain growth
Consists of additional growth and refinement of established brain structures as a result of specific learning experiences that occur throughout our lives, varying widely across individuals and cultrues
Is a wasted condition of the body caused by a diet low in all essential nutrients. It usually appears in the first year of life when a baby's mother is too malnourished to produce enough breast milk and bottle-feeding is also inadequate
Caused by an unbalanced diet very low in protein. The disease usually strikes after weaning, between 1 and 3 years of age
Food insecurity
17% of U.S. Children suffer from this--uncertain access to enough food for a healthy, active life
Nonorganic failure to thrive
A growth disorder resulting from lack of parental love, is usually present by 18 months of age. Infants who have it show all the signs of marasmus--their bodies look wasted, and they are withdrawn and apathetic. But no organic (or biological) cause for the baby's failure to grow can be found
Classical conditioning
Possible in the young infant. In this form of learning, a neutral stimulus is paired with a stimulus that leads to a reflexive response. Once the baby's nervous system makes the connection between the two stimuli, the neutral stimulus produces the behavior by itself
Unconditioned stimulus
Must produce a reflexive, unconditioned response
Conditioned stimulus
If learning has occurred, the neutral stimulus by itself produces a response similar to the reflexive response. The neutral stimulus becomes this.
Conditioned response
The response from the conditioned stimulus elicits this
Operant conditioning
Infants act, or operate, on the environment, and stimuli that follow their behavior change the probability that the behavior will occur again.
A stimulus that increases the occurrence of a response
Removing a desirable stimulus or presenting an unpleasant one to decrease the occurrence of a response
A gradual reduction in the strength of a response due to repetitive stimulation
A new stimulus--a change in the environment--causes responsiveness to return to a high level
Copying the behavior of another person
Mirror neurons
Specialized identified cells in motor areas of the cerebral cortex in primates--they fire identically when a primate hears or sees an action and when it carries out that action on its own
Gross-motor development
Refers to control over actions that help infants get around in the environment, such as crawling, standing, and walking
Fine-motor development
Smaller movements, such as reaching and grasping
Dynamic systems theory of motor development
Mastery of motor skills involves acquiring increasingly complex systems of action. When motor skills work as a system, separate abilities blend together, each cooperating with others to produce more effective ways of exploring and controlling the environment
Dynamic systems theory of motor development skills
(1) central nervous system development (2) the body's movement capacities (3) the goals the child has in mind (4) environmental supports for the skill
Newborns make poorly coordinated swipes or swings to objects in front of them, but because of poor arm and hand control, they rarely contact the object
Ulnar grasp
A clumsy motion in which the fingers close against the palm
Pincer grasp
By the end of the first year, infants use the thumb and index finger opposably in a well-coordinated __________
Statistical learning capacity
Analyzing speech stream for patterns--repeatedly occurring sequences of sounds--they acquire a stock of speech structures for which they will later learn meanings, long before they start to talk around age 12 months
Contrast sensitivity
Explains early pattern preferences. Refers to the difference in the amount of light between adjacent regions in a pattern. If babies are sensitive to (can detect) the contrast in two or more patterns, they prefer the one with more contrast
Intermodal perception
We make sense of these running streams of light, sound, tactile, odor, and taste information by perceiving them as unified wholes. We know, for example, that an object's shape is the same whether we see it or touch it; that breaking a glass causes a sharp, crashing sound; and that the patter of footsteps signals the approach of a person
Amodal sensory properties
Information that overlaps two or more sensory systems, such as rate, rhythm, duration, intensity, temporal synchrony (for vision & hearing), and texture and shape (for vision & touch)
Differentiation Theory
Infants actively search for invariant features of the environment--those that remain stable--in a constantly changing perceptual world