Blocking—the inability to condition a second stim-
ulus because of prior conditioning to another
stimulus that is also present during training.
Blood/brain barrier— a collection of cells that
press together against the walls of capillaries to
block many substances from entering the brain,
while allowing others to pass.
Borderline personality disorder—maladaptive
behavior characterized by rapidly shifting and
unstable mood, self-concept, and interpersonal
relationships, as well as impulsiveness; self-mutilation
and anger directed inwards; promiscuity and
other self-destructive habits like drug addiction
common.
Brain—portion of the central nervous system above
the spinal cord.
Brainstem—also called the hindbrain, includes the
medulla, pons, and cerebellum.
Brainstorming—a popular technique practiced
during creative problem solving that encourages
the generation of many ideas in a nonjudgmental
environment.
Broadbent filter theory of memory—inputs are
analyzed for each stage of memory and most fil-
tered out; only the most important are encoded.
Broca’s area—region in left frontal lobe that con-
trols production of speech.
Bulimia nervosa—an eating disorder characterized
by a pattern of eating binges involving intake of
thousands of calories, followed by purging either
by vomiting or using laxatives.
Bystander effect—tendency for an observer to be
less likely to give aid if other observers are present.
Cannon–Bard theory—theory that emotions and
physiological states occur simultaneously.
Cardinal trait—defining personality characteristic,
in a small number of us, that dominates and
shapes our behavior (according to Allport).
Case study—intensive investigation of the behavior
and mental processes associated with a specific
person or situation.
Catastrophes—stressors that are unpredictable,
large-scale disasters which threaten us.
Catatonic schizophrenia—a psychotic disorder
characterized by bizarre motor behavior which
sometimes takes the form of an immobile stupor
and waxy flexibility.
Catharsis—in Freudian psychoanalysis, the release
of emotional tension after remembering or reliving
an emotionally charged experience from the past;
as a coping device for stress, the release of pent up
emotions through exercise or other means.
Cell body—also called the cyton or soma, the part
of the neuron that contains cytoplasm and the
nucleus which directs synthesis of such substances
as neurotransmitters.
Central nervous system (CNS)—brain and spinal
cord.
Central route of persuasion—according to the
elaboration likelihood model, changes attitudes
by requiring a person to think critically about an
argument; usually results in stable change of atti-
tudes.
Central tendency—average or most typical scores of
a set of research data or distribution.
Central trait—a general characteristic that shapes
much of our behavior (according to Allport).
Cerebellum—part of the brainstem that controls
posture, equilibrium and movement.
Cerebral Cortex—convoluted part of forebrain that
is the center for higher order processes such as
thinking, planning, judgment; receives and
processes sensory information and directs move-
ment.
Chaining—an operant conditioning technique used
to teach complex behaviors; a number of behav-
iors must be done successively before the reward is
given.
Chromosome—structure in the nucleus of cells that
contains genes determined by DNA sequences.
Chunking—grouping information into meaningful
units; expands the capacity of short-term memory
beyond 7 unrelated bits of information.
Circadian rhythms—daily patterns of changes that
cycle approximately every 24 hours such as the
sleep/wake cycle.
Classical conditioning—learning which takes place
when two or more stimuli are presented together;
unconditioned stimulus is paired repeatedly with
a neutral stimulus until it acquires the capacity to
elicit a similar response.
Client-centered or person-centered therapy—
humanistic therapy introduced by Carl Rogers in
which the client rather than the therapist directs
the treatment process.
Clinical depression—also called major depression,
characterized by persistent and severe feelings
of sadness (dysphoria) and worthlessness
accompanied by changes in appetite, sleeping,
and behavior.316 ❯ Glossary