189Anxiety
 Disorders
Anxiety disorders  include disorders that share feat ures of excessive fear and anxi-
ety and related behavioral disturbances. Fear  is the emotional response to real or per-
ceived imminent threat, whereas anxiety is anticipation of future threat. Obviously, these
two states overlap, but they a lso differ, with fear more ofte n associated with surges of au-
tonomic arousal necessary for fight or flight , thoughts of immediate danger, and escape
behaviors, and anxiety more often associated with muscle tension and vigilance in prep-
aration for future danger and cautious or avoidant behavior s. Sometimes the level of fear
or anxiety is reduced by pervasive avoidance behaviors. Panic attacks  feature prominently
within the anxiety disorders as a particular ty pe of fear response. Panic attacks are not lim-
ited to anxiety disorders but rather can be  seen in other mental disorders as well.
The anxiety disorders differ from one anothe r in the types of objects or situations that
induce fear, anxiety, or avoidance behavior, and the associated cognitive ideation. Thus,
while the anxiety disorders tend to be highly comorbid with each other, they can be dif-
ferentiated by close examination of the types of  situations that are feared or avoided and
the content of the associated thoughts or beliefs. 
Anxiety disorders differ from developmentally  normative fear or anxiety by being ex-
cessive or persisting beyond developmentally appropriate periods. They differ from tran-
sient fear or anxiety, often st ress-induced, by being persistent (e.g., typically lasting 6 months
or more), although the criterion for duration is intended as a general guide with allowance
for some degree of flexibility and is sometimes of shorter duration in children (as in sepa-
ration anxiety disorder  and selective mutism). Since in dividuals with anxiety disorders