norm (p. 86)
An average, or standard, measurement, calculated from the measurements of many individuals within a specific group or population.
head-sparing (p. 87)
A biological mechanism that protects the brain when malnutrition disrupts body growth. The brain is the last part of the body to be damaged by malnutrition.
neuron (p. 88)
One of billions of nerve cells in the central nervous system, especially in the brain.
cortex (p. 88)
The outer layers of the brain in humans and other mammals. Most thinking, feeling, and sensing involve the cortex. (Sometimes called the neocortex.)
neurotransmitter (p. 88)
A brain chemical that carries information from the axon of a sending neuron to the dendrites of a receiving neuron.
prefrontal cortex (p. 90)
The area of the cortex at the front of the brain that specializes in anticipation, planning, and impulse control.
shaken baby syndrome (p. 91)
A life-threatening injury that occurs when an infant is forcefully shaken back and forth, a motion that ruptures blood vessels in the brain and breaks neural connections.
REM (rapid eye movement) sleep (p. 93)
A stage of sleep characterized by flickering eyes behind closed lids, dreaming, and rapid brain waves.
reflex (p. 94)
An unlearned, involuntary action or movement emitted in response to a particular stimulus. A reflex is an automatic response that is built into the nervous system and occurs without conscious thought.
gross motor skills (p. 95)
Physical abilities involving large body movements, such as walking and jumping. (The word gross here means "big.")
fine motor skills (p. 96)
Physical abilities involving small body movements, especially of the hands and fingers, such as drawing and picking up a coin. (The word fine here means "small.")
sensation (p. 97)
The response of a sensory system (eyes, ears, skin, tongue, nose) when it detects a stimulus.
perception (p. 97)
The mental processing of sensory information when the brain interprets a sensation.
binocular vision (p. 98)
The ability to focus the two eyes in a coordinated manner in order to see one image.
immunization (p. 100)
A process that stimulates the body's immune system to defend against attack by a particular contagious disease. Immunization may be accomplished either naturally (by having the disease) or through vaccination (often by having an injection). (Also called inoculation or vaccination.)
sudden infant death syndrome (SIDS) (p. 103)
A situation in which a seemingly healthy infant, at least 2 months of age, suddenly stops breathing and dies unexpectedly while asleep.
co-sleeping (p. 103)
A custom in which parents and their children (usually infants) sleep together in the same bed. (Also called bed-sharing.)
sensorimotor intelligence (p. 105)
Piaget's term for the way infants think—by using their senses and motor skills—during the first period of cognitive development.
assimilation (p. 106)
Piaget's term for a type of adaptation in which new experiences are interpreted to fit into , or assimilate with, old ideas.
accommodation (p. 106)
Piaget's term for a type of adaptation in which old ideas are restructured to include, or accommodate, new experiences.
object permanence (p. 107)
The realization that objects (including people) still exist when they can no longer be seen, touched, or heard.
"little scientist" (p. 108)
The stage-five toddler (age 12 to 18 months) who experiments without anticipating the results, using trial and error in active and creative exploration.
information-processing theory (p. 108)
A perspective that compares human thinking processes, by analogy, to computer analysis of data, including sensory input, connections, stored memories, and output.
visual cliff (p. 109)
An experimental apparatus that gives an illusion of a sudden dropoff between one horizontal surface and another.
reminder session (p. 110)
A perceptual experience that is intended to help a person recollect an idea, a thing, or an experience, without testing whether the person remembers it at the moment.
child-directed speech (p. 112)
The high-pitched, simplified, and repetitive way adults speak to infants. (Also called baby talk or motherese.)
babbling (p. 113)
The extended repetition of certain syllables, such as ba-ba-ba, that begins when babies are between 6 and 9 months old.
naming explosion (p. 113)
A sudden increase in an infant's vocabulary, especially in the number of nouns, that begins at about 18 months of age.