analytical (facts), practical (“street smarts”), cre-
ative (seeing multiple solutions).
Trichromatic theory—proposed mechanism for
color vision with cones that are differentially sensi-
tive to different wavelengths of light; each color
seen results from a specific ratio of activation
among the three types of receptors.
Turner syndrome—a group of symptoms in females
with only one X sex chromosome, including short-
ness, sterility, webbed neck, and difficulty with
calculations.
Type A personalities—hard-driving, competitive,
impatient, and ambitious individuals.
Type B personalities—more relaxed and calm
individuals.
Unconditional positive regard—Rogers’ term for
acceptance, value, and love from others independ-
ent of how we behave.
Unconditioned response(UCR)—in classical condi-
tioning, the unlearned, naturally occurring
response (reaction) to the unconditioned stimulus.
Unconditioned stimulus(UCS)—in classical condi-
tioning, the stimulus (change) that naturally and
automatically triggers the reflexive unconditioned
response (UR).
Unconscious—the level of consciousness of which
we are unaware, that may include unacceptable
feelings, wishes, and thoughts not directly available
to conscious awareness, according to psychody-
namic psychologists/psychoanalysts. According to
cognitive psychologists, the unconscious is the level
of consciousness that parallel processes informa-
tion of which we are unaware.
Unconsciousness—characterized by loss of respon-
siveness to the environment resulting from disease,
trauma, or anesthesia.
Undifferentiated schizophrenia—simple schizo-
phrenia characterized by fragments of the symp-
toms of other, different types of schizophrenia.
Uninvolved parenting style—characterized by few
demands, low responsiveness, little communica-
tion, and general detachment from a child’s life.
Validity—the extent to which an instrument meas-
ures or predicts what it is supposed to.
Variability—the spread or dispersion of a set of
research data or distribution.
Variable interval—schedule of reinforcement in
which responses are reinforced after varying
lengths of time (in operant conditioning).
Variable ratio—schedule of reinforcement in which
reinforcement is presented after a varying number
of responses (in operant conditioning).
Vestibular sense—body sense of equilibrium with
hairlike receptors in semicircular canals and
vestibular sac in the inner ear.
Visual capture—dominance of vision when there is a
conflict among senses.
Visual encoding—the encoding of pictorial images
into our memory.
We b e r’s l a w—difference thresholds increase in pro-
portion to the size of the stimulus.
Wernicke’s area—region in left temporal lobe that
plays role in understanding language and making
meaningful sentences.
Weschler intelligence tests—the most widely used
measurement of intelligence; three age-related
individual IQ tests (WPPSI, WISC, WAIS) that
provide two scores, verbal and performance.
Withdrawal—intense craving for a drug accompa-
nied by effects opposite of those the drug usually
induces.
Womb envy—Horney’s counterpart to penis envy of
Freudian theory; male’s desire to procreate.
Yerkes-Dodson rule—for easy tasks, moderately
high arousal is needed to do well; for difficult tasks,
moderately low; and most average tasks, moderate
level of arousal.
Zone of proximal development (ZPD)—according
to Vygotsky, the range between the level at which a
child can solve a problem working alone with dif-
ficulty, and the level at which a child can solve a
problem with the assistance of adults or more-
skilled children.
Zygote—a fertilized egg with the genetic instructions
for a new individual normally contained in 46
chromosomes.Glossary Ü 339