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Disrupting Reconsolidation of Fear Memory in Humans by a Noradrenergic β-Blocker
Published on: December 18, 2014
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Fear expression is suppressed by tyrosine administration.
Alessandro Soranzo1, Luca Aquili2
1Department of Psychology, Sociology and Politics, Sheffield Hallam University, Sheffield, UK.
Scientific Reports
|November 7, 2019
Summary
Tyrosine administration before fear conditioning significantly reduced fear expression in humans. This suggests the catecholaminergic system plays a crucial role in modulating fear responses.
Area of Science:
- Neuroscience
- Psychopharmacology
- Human Fear Conditioning
Background:
- Catecholamines are known to regulate fear conditioning in animal models.
- Human studies on the catecholaminergic system's role in fear are limited, often intervening post-acquisition.
Purpose of the Study:
- To investigate the effect of pre-conditioning tyrosine administration on human fear expression.
- To determine if increasing presynaptic dopamine and norepinephrine influences fear recall.
Main Methods:
- An instructed fear task was employed with 46 healthy participants.
- Participants received either tyrosine or a placebo before the fear conditioning protocol.
- Electrodermal activity (EDA) was measured to assess fear responses.
Main Results:
- Tyrosine administration significantly abolished fear expression compared to the placebo group.
- Tyrosine did not alter electrodermal activity responses to the unconditioned stimulus (UCS).
- Participant mood and general arousal were unaffected by tyrosine supplementation.
Conclusions:
- Pre-conditioning tyrosine administration effectively reduces fear expression in humans.
- The catecholaminergic system, influenced by tyrosine, modulates human fear expression.
- These findings highlight a potential therapeutic target for anxiety disorders.
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