Healthy
Conditions
Keywords
Threat conditioning, Virtual reality, Extinction, Behavioral tagging
Brief summary
In rodents, novel exploration has been used to strengthen the consolidation of a variety of hippocampal-dependent learning tasks. To our knowledge, no attempt have been made to translate the effect of strengthening the memory of an extinction of a context conditioning memory. This study uses virtual reality for both context conditioning and novel exploration in an attempt at translating these findings from rodents to humans, thus, using novel exploration to strengthen an extinction memory. Threat responses are measured with skin conductance and startle responses. If this effect could be shown experimentally in humans, that experimental setup could become an important tool in understanding important memory processes of fear, such as reconsolidation and behavioral tagging.
Detailed description
The study employs healthy participants and includes three experimental sessions, roughly 24 h apart. During the first session, participants undergo context conditioning in virtual reality where the CS+ and CS- are two different rooms. During the second session, half of the participants perform an exploration of a novel virtual environment, and the other half performs a visual attention task. About 60 min later, participants undergo extinction to the context conditioning performed in session 1, again in virtual reality. In session 3, remaining threat responses are measured through a reinstatement procedure, again in virtual reality.
Interventions
BEHAVIORALNovel Exploration
Exploration of a novel 3D-environment in virtual reality.
BEHAVIORALThreat conditioning
Session 1. Threat conditioning to two different (CS+, CS-) virtual reality contexts (i.e rooms). One of these is paired with a mild electric shock. The context paired with the electric shock (CS+) is counterbalanced across participants. Participants are instructed that they may receive electrical shocks during the procedure.
BEHAVIORALExtinction
Session 2. Participants are repeatedly exposed to the both contexts from session 1 (CS+, CS-), but no shocks are delivered.
BEHAVIORALReinstatement
Session 3. Participants are again repeatedly exposed to both contexts from session 1 (CS+, CS-), after a few shocks delivered in a neutral context.
BEHAVIORALVisual attention control task
Session 2. A visual attention task used as a control task instead of novel exploration.
Sponsors
Uppsala University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
SINGLE (Subject)
Masking description
Participants are never told which manipulation that is expected to affect the threat memory processes.
Eligibility
Sex/Gender
ALL
Age
18 Years to 50 Years
Healthy volunteers
Yes
Inclusion criteria
* Willing and able to provide informed consent and complete study procedures
Exclusion criteria
* Current psychiatric disorder. * Current use of psychotropic medication * Current use of neurological conditions
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Physiological arousal response during reinstatement. | Day 3 | Startle responses and skin conductance responses are used as measures of physiological arousal response. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Physiological arousal response during extinction | Day 2 | Startle responses and skin conductance responses are used as measures of physiological arousal response |
| Physiological arousal response during threat conditioning | Day 1 | Startle responses and skin conductance responses are used as measures of physiological arousal response |
| Subjective fear ratings | Day 1, 2 & 3. | Subjective ratings of fear (0-100) where 0 is no fear and 100 is worst imaginable fear. |
| Subjective discomfort ratings | Day 1, 2 & 3 | Subjective ratings of discomfort where 0 is no discomfort and 100 is worst imaginable discomfort. |
Other
| Measure | Time frame | Description |
|---|---|---|
| State-Trait Anxiety Inventory (STAI-T) | Day 2 | This is a self-rated questionnaire measuring trait anxiety. Higher scores indicate higher level of trait-anxiety (range 20-80). |
| Generalized anxiety disorder 7 (GAD-7) | Day 2 | This is a self-rated questionnaire for screening and severity measuring of generalized anxiety disorder (range 0-21). Higher scores indicate more symptoms of generalized anxiety. |
| Patient Health Questionnaire 9 (PHQ-9) | Day 2 | This is a self-rated questionnaire for screening for the presence and severity of depression (0-27). Higher scores indicate a more symptoms, and severity of symptoms, of depression |
| Navigation success | Day 2 | Questions designed to probe the amount of navigation performed by participants doing the novel exploration task. Three yes/no question of Did you find object X? and then participants are asked to point at their position in a stylized map overviewing the novel exploration context. |
Countries
Sweden
Outcome results
None listed