PSY 231 1st EditionExam # 2 Study Guide Lectures: 5 – 13 Lecture 5, Chapter 4: Physical development in infancy and toddlerhood- first two years (February 16)Cephalocaudal trend- from the Latin for “head to tail,” a trend in body growth that indicates that during the prenatal period the heart develops more rapidly than the lower part of the bodyProximodistal trend- trend that indicates that growth proceeds from “near to far,” or from the center of the body outwardNeurons- nerve cells that store and transmit information, not tightly packed togetherSynapses- tiny gaps between neurons where their different fibers come close together but do not touchNeurotransmitters- chemicals released by neurons that cross the synapse and send messagesSynaptic pruning- returns neurons not needed at the moment to an uncommitted states so theycan support future development—neurons seldom stimulated lose their synapsesGlial cells- accounts for the dramatic increase in brain size during the first two years, and consists of half the brain’s volumeMyelination- possible because of glial cells, it is the coating of neural fibers with an insulating fatty sheath (myelin) that improves the efficiency of message transfer between neuronsCerebral cortex- surrounds the rest of the brain and resembles a half of a shelled walnut. It is the largest, most complex brain structure and accounts for 85% of the brain’s weight and contains the greatest number of neurons and synapsesLateralization- specialization of the two hemispheresBrain plasticity- indicates a high capacity for learning where many areas are not yet committed to specific functions. If part of the cortex is damaged, other parts can take over the tasks it would have handledExperience-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 environmentExperience-dependent brain growth- 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 culturesMarasmus- wasted condition of the body caused by a diet low in all essential nutrients. 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 inadequateKwashiorkor- caused by an unbalanced diet very low in protein. Usually strikes after weaning, between 1 and 3 years of ageNonorganic failure to thrive- growth disorder resulting from lack of parental love. Usually present by 18 months of age in infants where all signs of marasmus are present. Bodies look wasted, and they are withdrawn and apathetic. No organic or biological cause for the baby’s failure to grow can be foundClassical conditioning- 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 response produces the behavior by itself Unconditioned stimulus- a stimulus that produces a reflexive or unconditioned responseConditioned stimulus- originally the neutral stimulus that causes a conditioned responseOperant conditioning- infant acts on the environment, and stimuli that follow their behavior change the probability that the behavior will occur againReinforcer- a stimulus that increases the occurrence of a responsePunishment- removing a desirable stimulus or presenting an unpleasant one to decrease the occurrence of a responseHabituation- a gradual reduction in the strength of a response due to repetitive stimulationRecovery- a new stimulus (a change in the environment) causes responsiveness to return to a high levelImitation- copying the behavior of another personMirror neurons- specialized cells in motor areas of the cerebral cortex in primates that underlie the capacity to actively try to match body movements they see with ones they feel themselves make. These neurons fire identically when a primate hears or sees an action and when it carries out that action on its ownDynamic 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 environmentStatistical learning capacity- by analyzing the speech stream for patterns, infants acquire a stock of speech structures for which they will later learning meanings, long before they start to talk around age 12 monthsContrast sensitivity- explains early pattern preferences. If babies are sensitive to the contrast in two or more patterns, they prefer the one with more contrastIntermodal perception- making sense of running streams of light, sound, tactile, odor, and tasteinformation by perceiving them as unified wholesDifferentiation theory- infants actively search for invariant features of the environment—those that remain stable—in a constantly changing perceptual worldLecture 6, Chapter 5: Cognitive development in infancy and toddlerhood- first two years (February 18)Sensorimotor stage- spans the first two years of life, where Piaget believed infants and toddlers “think” with their eyes, ears, hands, and other sensorimotor equipment—they cannot yet carry out many activities inside their headsSchemes- specific psychological structures organized in a way of making sense of experiencesAdaptation- building schemes through indirect interaction with the environmentAssimilation- using our correct schemes to interpret the external worldAccommodation- creating new schemes or adjusting old ones after noticing that our current ways of thinking do not capture the environment completely Organization- process that takes place internally, apart from direct contact with the environment. Once children form new schemes, they rearrange them, linking them with other schemes to create a strongly interconnected cognitive systemCircular reaction- provides a special means of adapting to first schemes involving stumbling intoa new experience cause by the baby’s own motor activity. The reaction is circular because as theinfant tries to repeat the event again and again, a sensorimotor response that first occurred by change becomes strengthened into a new schemeIntentional behavior- also known as