Ignite Creation Date:
2024-05-05 @ 11:26 AM
Last Modification Date:
2024-10-26 @ 9:08 AM
Study NCT ID:
NCT00047853
Status:
COMPLETED
Last Update Posted:
2024-03-12
First Post:
2002-10-22
Brief Title:
Brain Imaging Changes in Fear and Anxiety
Sponsor:
National Institute of Mental Health NIMH
Organization:
National Institutes of Health Clinical Center CC
Study Overview
Official Title:
fMRI Investigation of Explicit Cue and Contextual Fear
Status:
COMPLETED
Status Verified Date:
2022-08-02
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
The purpose of this study is to use brain imaging technology to investigate brain changes in people exposed to predictable versus unpredictable unpleasant stimuli Unpleasant events that can be predicted evoke a response of fear whereas unpredictable unpleasant stimuli cause chronic anxiety not associated with a specific event Information gained from this study may help in the development of more effective treatments for anxiety disorders
When confronted with fearful events people eventually develop fear of specific cues that were associated with these events as well as to the environmental context in which the fearful event occurred Evidence suggests that cued fear and contextual fear model different aspects of anxiety However studies that examine the way the brain affects expression of contextual fear have not been conducted This study will use magnetic resonance imaging MRI or Magneto-encephalography MEG to compare the brain activity underlying fear brought on by predictable and unpredictable aversive stimuli
When confronted with fearful events people eventually develop fear of specific cues that were associated with these events as well as to the environmental context in which the fearful event occurred Evidence suggests that cued fear and contextual fear model different aspects of anxiety However studies that examine the way the brain affects expression of contextual fear have not been conducted This study will use magnetic resonance imaging MRI or Magneto-encephalography MEG to compare the brain activity underlying fear brought on by predictable and unpredictable aversive stimuli
Detailed Description:
This protocol examines the neurobiology of fear and anxiety using various approaches During fear conditioning in which a phasic explicit cue eg a light is repeatedly associated with an aversive unconditioned stimulus eg a shock the organism develops fear to the explicit cue as well as to the environmental context in which the experiment took place Experimental evidence suggests that cued fear and contextual fear model different aspects of anxiety Studies in patients indicated that contextual fear may model an aspect that is especially relevant to anxiety disorders However the neural basis for the expression of contextual fear has not previously been elucidated in human imaging studies One important determinant of contextual fear is predictability contextual fear increases when a threat eg electric shock is unpredictable as opposed to when the threat is predictable The aim of this study is to compare the neural substrates underlying fear evoked by predictable versus unpredictable shocks Animal studies have indicated that conditioned responses to predictably cued threat and to less explicit threat are separate processes mediated by distinct brain structures Psychophysiological data suggest that the proposed procedure can differentiate between these two responses Hence we anticipate that this procedure will allow us to compare brain correlates of these responses in humans Another objective is to study effects of threat of shock on processing and learning of threat cues in the amygdala the visual and auditory systems and motivationreward systems This will be investigated by means of event-related magneto-encephalography MEG and fMRI measurements using various paradigms Finally a last project will examine how pharmacologic manipulation of gamma-aminobutyric acid GABA levels with the benzodiazepine alprazolam affects the relationship between GABA concentration quantified with magnetic resonance spectroscopy MRS visual- and auditory-induced gamma oscillations measured with MEG and fMRI BOLD response
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
False
Is a FDA Regulated Device?:
True
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None
Secondary IDs
| Secondary ID | Type | Domain | Link |
|---|---|---|---|
| 02-M-0321 | None | None | None |