The Effect of Intravenous Anesthetics on Fear Learning and Memory - Full Text View

Sponsored by:	Weill Medical College of Cornell University
Information provided by:	Weill Medical College of Cornell University
ClinicalTrials.gov Identifier:	NCT00767767

Purpose

People often develop fearful responses to things, but have no conscious control over the fear (e.g. phobias). This is a basic form of unconscious memory, called ÃƒÂ¢Ã¢â€-Â¬Ã<Å"fear conditioningÃƒÂ¢Ã¢â€-Â¬Ã¢"Â¢. Intravenous anesthetic drugs have remarkable effects on conscious memory, but it is unknown whether they have similar effects on these unconscious fear memories.

To address this question, the investigators will study 90 healthy adult volunteer subjects. The subject is given a very low dose of an anesthetic drug intravenously (i.e. through the bloodstream). The dose is so low that the subject might not even be able tell if they are getting the drug. While they are receiving the drug, the subject will perform a series of memory tests and a fear conditioning experiment, which are set up like a very simple computer game. To create the ÃƒÂ¢Ã¢â€-Â¬Ã<Å"fear responseÃƒÂ¢Ã¢â€-Â¬Ã¢"Â¢, subjects will occasionally receive a mildly uncomfortable shock to their arm. The subject is able to determine the highest level of shock that they will receive.

The investigators are doing this study because the investigators wish to know exactly how the drugs affect the way people process fear and emotion. This knowledge might one day be used in the treatment of some psychiatric disorders.

Condition	Intervention
Phobias	Drug: Propofol Drug: Placebo Drug: Thiopental Drug: Midazolam Drug: Dexmedetomidine

MedlinePlus related topics: Anesthesia Memory Phobias

Drug Information available for: Midazolam Midazolam hydrochloride Midazolam maleate Propofol Dexmedetomidine Dexmedetomidine hydrochloride Thiopental Thiopental sodium

U.S. FDA Resources

Study Type:	Interventional
Study Design:	Basic Science, Randomized, Single Blind (Subject), Placebo Control, Parallel Assignment, Pharmacodynamics Study
Official Title:	The Effect of Intravenous Anesthetics on Fear Learning and Memory

Further study details as provided by Weill Medical College of Cornell University:

Primary Outcome Measures:

Changes in skin conductance [ Time Frame: Throughout Study ] [ Designated as safety issue: No ]
Changes in the eye-blink reflex following an auditory startle probe [ Time Frame: Throughout Study ] [ Designated as safety issue: No ]
Changes in heart-rate variability [ Time Frame: Throughout Study ] [ Designated as safety issue: No ]

Estimated Enrollment:	90
Study Start Date:	October 2008
Estimated Study Completion Date:	December 2009
Estimated Primary Completion Date:	December 2009 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
1: Placebo Comparator Saline Infusion.	Drug: Placebo IV Saline infusion for 2 hours.
2: Active Comparator Anesthetic Drug Infusion.	Drug: Propofol IV Propofol infusion for 2 hours. Drug: Thiopental IV Thiopental infusion for 2 hours. Drug: Midazolam IV Midazolam infusion for 2 hours. Drug: Dexmedetomidine IV Dexmedetomidine Infusion for 2 hours.

Eligibility

Ages Eligible for Study:	18 Years to 50 Years
Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	Yes

Criteria

Inclusion Criteria:

age between 18 and 50
right handed
minimum of high school education
fluent in English
normal vocabulary

Exclusion Criteria:

any significant medical or psychiatric comorbidity (e.g. asthma, diabetes, hypertension, depression, high anxiety)â€"subjects must be in excellent health such that they would be classified as American Society of Anesthesiologists Physical Status Class I
deficit in vision or hearing that would impede the study
allergies to any of the study drugs, to soybeans, or to eggs
a history of head trauma
a family history of major psychiatric illness
body mass index > 30 kg/m2
a recent history of recreational drug use
prior exposure to the study materials
pregnancy
a personal or family history of any porphyria
(xi) failure to exhibit a skin conductance response to deep inspiration; (xii) the ability to read native Chinese characters
assessment by the investigators that the subject may be unable to cooperate or comply with the study requirements.

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00767767

Contacts

Contact: Jackie Bogan, B.A.

212-746-9419

jab2035@med.cornell.edu

Locations

United States, New York
Weill Cornell Medical College/New York Presbyterian Hospital	Recruiting
New York, New York, United States, 10065
Contact: Jackie Bogan, B.A. 212-746-9419 jab2035@med.cornell.edu
Principal Investigator: Kane Pryor, MD

Sponsors and Collaborators

Weill Medical College of Cornell University

Investigators

Principal Investigator:

Kane Pryor, MD

Weill Cornell Medical College

More Information

Responsible Party:	Weill Cornell Medical College ( Kane Pryor )
Study ID Numbers:	0710009434
Study First Received:	October 3, 2008
Last Updated:	October 6, 2008
ClinicalTrials.gov Identifier:	NCT00767767
Health Authority:	United States: Food and Drug Administration

Keywords provided by Weill Medical College of Cornell University:

To investigate the effects of anesthetic drugs on associative memory processes involving fear

Study placed in the following topic categories:

Thiopental
Dexmedetomidine
Propofol
Midazolam
Phobic Disorders

Additional relevant MeSH terms:

Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Adrenergic Agents
GABA Modulators
Physiological Effects of Drugs
Psychotropic Drugs
Anesthetics
Adrenergic Agonists
Sensory System Agents
Therapeutic Uses
Hypnotics and Sedatives
Analgesics
Anesthetics, Intravenous

Tranquilizing Agents
Adrenergic alpha-Agonists
Central Nervous System Depressants
Pharmacologic Actions
Adjuvants, Anesthesia
Anesthetics, General
Analgesics, Non-Narcotic
GABA Agents
Anti-Anxiety Agents
Peripheral Nervous System Agents
Central Nervous System Agents
Anticonvulsants

ClinicalTrials.gov processed this record on January 16, 2009