Abstract
Fear can be an adaptive emotion that helps defend against potential danger. Classical
conditioning models elegantly describe how animals learn which stimuli in the environment
signal danger, but understanding how this learning is generalized to other stimuli
that resemble aspects of a learned threat remains a challenge. Critically, the overgeneralization
of fear to harmless stimuli or situations is a burden to daily life and characteristic
of posttraumatic stress disorder and other anxiety disorders. Here, we review emerging
evidence on behavioral and neural mechanisms of generalization of emotional learning
with the goal of encouraging further research on generalization in anxiety disorders.
We begin by placing research on fear generalization in a rich historical context of
stimulus generalization dating back to Pavlov, which lays the foundation for theoretical
and experimental approaches used today. We then transition to contemporary behavioral
and neurobiological research on generalization of emotional learning in humans and
nonhuman animals and discuss the factors that promote generalization on the one hand
from discrimination on the other hand.
Keywords
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Article info
Publication history
Published online: April 20, 2015
Accepted:
April 14,
2015
Received in revised form:
April 1,
2015
Received:
January 5,
2015
Identification
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