Temporal Dynamics of the Defense Cascade

Understanding physiological responses to threat can inform therapeutic interventions for phobias, anxieties, and PTSD. The defense cascade is reviewed as a theoretical model that predicts behavioral and physiological responses to threats. Nineteen undergraduates (five male), average age 19.4 experienced a novel virtual reality (VR) threat scenario while their physiology was measured. The Subjective Units of Distress Scale (SUDS) was used as a self-report indicator of distress in the research setting. Averaged SUDS reports suggested that the VR stimulus was experienced as threatening for most participants, but their autonomic response patterns did not fit those predicted by the defense cascade. Participants who had scored high on adaptive response questionnaires tended to show uncoupled ANS activation during baseline, but varied across the stimulus condition. Nearly all participants showed either coactivation or reciprocal activation during the stimulus period except those reporting the most dissociative trauma experiences, who mostly showed uncoupled ANS activation.

Name thesis:degree_name

M.S.

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Biological Psychology

Department dc:contributor.department

Psychology

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

2020

Author dc:creator

• Nackley, Brittany B.

Chair dc:contributor.committeechair

• Friedman, Bruce H.

Committee members dc:contributor.committeemember

• Ollendick, Thomas H.
• Jones, Russell T.

• defense cascade
• physiology
• autonomic nervous system
• sympathetic nervous system
• parasympathetic nervous system
• time series
• Subjective Units of Distress
• SUDS
• trauma
• autonomic space
• cardiac autonomic balance
• cardiac autonomic regulation

Statement dc:rights

• Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International

Licence dc:rights.uri

• http://creativecommons.org/licenses/by-nc-nd/4.0/

Language dc:language.iso

en_US

Handle dc:identifier.uri

http://hdl.handle.net/10919/99987

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/99987