Unit 1 Flashcards
Validity
degree to which it measures what it is meant to measure
internal validity
whether effects observed withing experiments can be attributed with confidence to the factor that the research is testing
For instance, suppose that a researcher tests the effectiveness of a type of psychotherapy for depression by administering it to a number of depressed adolescents. If, three months later, many of the adolescents are no longer depressed, can it be concluded that this type of psychotherapy caused the improvement? No, because the students’ recovery may have been due to the mere passage of time. Moods fluctuate, and many people who are depressed at any given time will be happier at a later date even without psychotherapy. In this example, the passage of time is a source of internal invalidity because the factor believed to cause the improvement (the psychotherapy) may have had no effect.
external validity
ability to generalize research findings to the general population
clinical interview
set of preped questions, can go off script if needed
- provide data quickly
- biased answers
structured observation
researchers design a situation that will elicit behavior and observe how children behave in that situation
control group
treated identically except that they are not presented the experience of interest or are presented wth a different experience that is expected to have less effect on the variables being tested
cross-sectional approach
This method compares children of different ages on a given behavior, ability, or characteristic by studying them at roughly the same time. useful for revealing similarities and differences between older and younger children. However, they do not yield information about the stability of behavior over time or about the patterns of change shown by individual children
Microgenetic designs
Microgenetic designs are like longitudinal ones in repeatedly testing the same children over time. They differ in that microgenetic studies typically include a greater number of sessions presented over a shorter time than in a longitudinal study. typically used when the basic pattern of age-related change has already been established and the goal becomes to understand how the changes occur
describe reproduction
the launching of an egg (the largest cell in the human female body) from one of the woman’s ovaries into the adjoining fallopian tube. As the egg moves through the tube toward the uterus, it emits a chemical substance that acts as a sort of beacon, a “come-hither” signal that attracts sperm toward it. If an act of sexual intercourse takes place near the time the egg is released, conception, the union of sperm and egg, is possible. In every ejaculation, as many as 500 million sperm are pumped into the woman’s vagina. Each sperm, a streamlined vehicle for delivering the man’s genes to the woman’s egg, consists of little more than a pointed head packed full of genetic material (the 23 chromosomes) and a long tail that whips around to propel the sperm through the woman’s reproductive system. As soon as one sperm’s head penetrates the outer membrane of the egg, a chemical reaction seals the membrane, preventing other sperm from entering. The tail of the sperm falls off, the contents of its head gush into the egg, and the nuclei of the two cells merge within hours. The fertilized egg, known as a zygote, now has a full complement of human genetic material, 23 chromosomes from the mother and 23 chromosomes from the father.
steroids such as glucocorticoids
limit fetal growth and help fetal tissues mature
twins
identical (monozygotic) twins result from a splitting in half of the inner cell mass, thus they have exactly the same genetic makeup. In contrast, fraternal (dizygotic) twins result when two eggs happen to be released from the ovary into the fallopian tube and both are fertilized
inner cell mass layers
The top layer becomes the nervous system, the nails, teeth, inner ear, lens of the eyes, and the outer surface of the skin. The middle layer becomes muscles, bones, the circulatory system, the inner layers of the skin, and other internal organs. The bottom layer develops into the digestive system, lungs, urinary tract, and glands.
amniotic sac
a membrane filled with a clear, watery fluid in which the fetus floats. The amniotic fluid operates as a protective buffer for the developing fetus, providing it with a relatively even temperature and cushioning it against jolting
placenta
rich network of blood vessels, weighing roughly one pound, that extends into the tissues of the mother’s uterus. is semipermeable: it permits the exchange of materials carried in the bloodstreams of the fetus and its mother, but it prevents the blood of the mother and fetus from mixing. Oxygen, nutrients, minerals, and some antibodies—all of which are just as vital to the fetus as they are to you—are transported to the placenta by the mother’s circulating blood. They then cross the placenta and enter the fetal blood system. Waste products (e.g., carbon dioxide and urea) from the fetus cross the placenta in the opposite direction and are removed from the mother’s bloodstream by her normal excretory processes. The placental membrane also serves as a defensive barrier against a host of dangerous toxins and infectious agents that can inhabit the mother’s body but would be harmful or even fatal to the fetus.
cephalocaudal development
earlier development takes place at a more rapid pace than later development and that the areas nearer the head develop earlier than those farther away (e.g., head before body, hands before feet)—a general tendency
teratogens
vast number of environmental agents that have the potential to harm the fetus. Many teratogens cause damage only if they are present during a sensitive period in prenatal development. The major organ systems are most vulnerable to damage at the time when their basic structures are being formed. Because the timing is different for each system, the sensitive periods are different for each system
neonatal abstinence syndrome (NAS)
a form of drug withdrawal seen when fetuses exposed to opioids in the womb are born
SIDS
sudden infant death syndrome
cephatocaudal
development begining at the head
- proximaldistal
embryonic period….
blastocyst attaches to the uterine wall and becomes an emgryo
- 3 layers: ectoderm, mesoderm (circulatory system), endoderm (lungs, digestive system, urinary track)
organogenesis
process of organ formation during the first 2-months of prenatal development
fetal development
- last phase
- gaining fat, practicing breathing, maturiting of organs
habituation
- demonstrates learning
- decrease in heart rate in response to a stimuli
- short term memory
dehabituation
- infant can detect something new
- a new high reponse
