Quantitative representations of an exaggerated anxiety response in the brain of female spider phobics-a parametric fMRI study.
We employed a novel parametric spider picture set in the context of a parametric fMRI anxiety provocation study, designed to tease apart brain regions involved in threat monitoring from regions representing an exaggerated anxiety response in spider phobics. For the stimulus set, we systematically manipulated perceived proximity of threat by varying a depicted spider's context, size, and posture. All stimuli were validated in a behavioral rating study (phobics n = 20; controls n = 20; all female). An independent group participated in a subsequent fMRI anxiety provocation study (phobics n = 7; controls n = 7; all female), in which we compared a whole-brain categorical to a whole-brain parametric analysis. Results demonstrated that the parametric analysis provided a richer characterization of the functional role of the involved brain networks. In three brain regions-the mid insula, the dorsal anterior cingulate, and the ventrolateral prefrontal cortex-activation was linearly modulated by perceived proximity specifically in the spider phobia group, indicating a quantitative representation of an exaggerated anxiety response. In other regions (e.g., the amygdala), activation was linearly modulated in both groups, suggesting a functional role in threat monitoring. Prefrontal regions, such as dorsolateral prefrontal cortex, were activated during anxiety provocation but did not show a stimulus-dependent linear modulation in either group. The results confirm that brain regions involved in anxiety processing hold a quantitative representation of a pathological anxiety response and more generally suggest that parametric fMRI designs may be a very powerful tool for clinical research in the future, particularly when developing novel brain-based interventions (e.g., neurofeedback training). Hum Brain Mapp 38:3025-3038, 2017. © 2017 Wiley Periodicals, Inc.
Department of Cognitive Neuroscience, Maastricht University, Oxfordlaan 55, Maastricht, EV 6229, The Netherlands.|Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York, 10029.
Anna
0000-0002-4889-9700
A
Zilverstand
Department of Cognitive Neuroscience, Maastricht University, Oxfordlaan 55, Maastricht, EV 6229, The Netherlands.
Bettina
B
Sorger
Department of Cognitive Neuroscience, Maastricht University, Oxfordlaan 55, Maastricht, EV 6229, The Netherlands.
Anita
A
Kaemingk
Department of Cognitive Neuroscience, Maastricht University, Oxfordlaan 55, Maastricht, EV 6229, The Netherlands.|Department of Neuroimaging and Neuromodeling, Netherlands Institute for Neuroscience (KNAW), Meibergdreef 47, Amsterdam, BA 1105, The Netherlands.
Rainer
R
Goebel
D000328:Adult; D001007:Anxiety / Q000209:etiology*; D001921:Brain / Q000000981:diagnostic imaging*; D001931:Brain Mapping; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D010100:Oxygen / Q000097:blood; D010698:Phobic Disorders / Q000150:complications* / Q000473:pathology*; D010775:Photic Stimulation; D011569:Psychiatric Status Rating Scales; D014796:Visual Perception; D055815:Young Adult
D010100:Oxygen
amygdala; anxiety disorders; insula; magnetic resonance imaging; neurofeedback; phobic disorders; spider phobia; spiders; subjective anxiety; threat