The Neural Substrates of Fear Extinction

Chapter

Abstract

Fear extinction is a key mechanism by which new, fear-inhibitory memories can be acquired, stored, and recalled. Knowledge about the neural mechanisms of fear extinction may have the potential to directly improve exposure-based therapies. In this chapter, we will review the neural circuitries of fear learning and unlearning. Starting with basic considerations about the nature of extinction and implications for experimental designs, the neural substrates of fear extinction learning and recall will be outlined, focusing on the respective roles of the amygdala, the ventro-medial prefrontal cortex, and the hippocampus. We will furthermore present new lines of evidence that challenge the traditional view of fear extinction as new learning, indicating that erasure-like extinction mechanisms can be induced under certain conditions. Finally, we will summarize available evidence for altered fear conditioning and extinction mechanisms in the anxiety disorders, including their behavioral and neural substrates.

Keywords

Placebo Magnesium Serotonin Expense NMDA 

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© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Institute of Clinical Psychology and PsychotherapyTechnische Universitaet DresdenDresdenGermany
  2. 2.Neuroimaging Center, Department of PsychologyTechnische Universitaet DresdenDresdenGermany

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