Understanding Psychology (10th Ed)

stage 2 sleep

 
A sleep deeper than that of stage 
1, characterized by a slower, more regular wave 
pattern, along with momentary interruptions of 
“sleep spindles” (Module 14).

stage 3 sleep

 
A sleep characterized by slow 
brain waves, with greater peaks and valleys 
in the wave pattern than in stage 2 sleep 
(Module 14).

stage 4 sleep

 
The deepest stage of sleep, dur-
ing which we are least responsive to outside 
stimulation (Module 14).

standard deviation

 
An index of the average 
deviation of a set of scores from the center of 
the distribution (Module 57).

statistics

 
The branch of mathematics concerned 
with collecting, organizing, analyzing, and 
drawing conclusions from numerical data 
(Module 56).

status

 
The social rank held within a group 
(Module 53).

stereotype

 
A set of generalized beliefs and 
expectations about a particular group and its 
members (Module 54).

stimulants

 
Drugs that have an arousal effect on 
the central nervous system, causing a rise in 
heart rate, blood pressure, and muscular ten-
sion (Module 16).

stimulus

 
Energy that produces a response in a 
sense organ (Module 10).

stimulus discrimination

 
The process that 
occurs if two stimuli are suffi ciently distinct 
from one another that one evokes a conditioned 
response but the other does not; the ability to 
differentiate between stimuli (Module 17).

stimulus generalization

 
A process in which, 
after a stimulus has been conditioned to pro-
duce a particular response, stimuli that are sim-
ilar to the original stimulus produce the same 
response (Module 17).