Influence of the Noradrenergic System on the Formation of Intrusive Memories

Influence of the Noradrenergic System on the Formation of Intrusive Memories: An Experimental Approach With a Trauma Film Paradigm

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT02541071

Enrollment

118

Registered

2015-09-04

Start date

2013-11-30

Completion date

2014-10-31

Last updated

2015-09-04

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Intrusive Memories

Brief summary

Intrusive memories of traumatic events are core features of posttraumatic stress disorder (PTSD) but little is known about the neurobiological formation of intrusions. The aim of this study was to determine whether the activity of the noradrenergic system during an intrusion-inducing stressor influences subsequent intrusive memories.

Detailed description

The investigators conducted an experimental, double-blind, placebo-controlled study in 118 healthy women. Prior to watching an established trauma film paradigm that induces short lasting intrusions, participants received a single dose of either 10 mg yohimbine, stimulating noradrenergic activity, or 0.15 mg clonidine, inhibiting noradrenergic activity, or placebo. The number of consecutive intrusions of the trauma film, the mean vividness of the intrusions and the mean degree of distress evoked by the intrusions were assessed during the following four days. Salivary cortisol and alpha-amylase were collected at seven time points prior to, and after the trauma film.

Interventions

BEHAVIORALStress Film

DRUGYohimbine

DRUGClonidine

DRUGplacebo

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

BASIC_SCIENCE

Masking

DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender

FEMALE

Age

18 Years to 44 Years

Healthy volunteers

Yes

Inclusion criteria

* healthy participants * German on a native level

Exclusion criteria

* former or present DSM IV Axis I disorders * physical illnesses * any medication intake (except oral contraceptive) * history of sexual abuse or rape * pregnancy or lactation period

Design outcomes

Primary

Measure	Time frame	Description
Number of intrusive memories	four consecutive days	Measured with an intrusion diary

Secondary

Measure	Time frame	Description
Vividness of intrusive memories	four consecutive days	Measured with an intrusion diary
Degree of distress of intrusive memories	four consecutive days	Measured with an intrusion diary

Countries

Germany

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026