The Effect of Intravenous Anesthetics on Fear Learning and Memory

Summary

People often develop fearful responses to things, but have no conscious control over the fear. This is a basic form of unconscious memory, called "fear conditioning." 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 114 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 "fear response", 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.

Conditions

• Phobias

Interventions

DRUG

Placebos

IV Saline infusion for 2 hours.

DRUG

Propofol 0.45mcg/mL

IV Propofol infusion for 2 hours.

DRUG

Propofol 0.90mcg/mL

IV Propofol infusion for 2 hours.

DRUG

Thiopental 1.5mcg/mL

IV Thiopental 1.5mcg/mL infusion for 2 hours

DRUG

Thiopental 3mcg/mL

IV Thiopental 3mcg/mL infusion for 2 hours

Sponsors & Collaborators

• National Institutes of Health (NIH)

  collaborator NIH

• National Institute of General Medical Sciences (NIGMS)

  collaborator NIH

• Weill Medical College of Cornell University

  lead OTHER

Principal Investigators

• Kane Pryor, MD · Weill Medical College of Cornell University

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

50 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2008-10-31

Primary Completion

2011-05-31

Completion

2011-05-31

Countries

• United States

Study Locations