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- Engman, Jonas, et al.
(författare)
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Neural Correlates of Anxiety States in Patients with Social Anxiety Disorder
- 2011
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Ingår i: Biological Psychiatry. - 0006-3223 .- 1873-2402. ; 69, s. 70S-70S
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Background: In social anxiety disorder (SAD), the fear of being negatively evaluated by others can restrict individual everyday life, due to the anxiety caused by social interactions. How this anxiety is processed in the brain is only partly understood. We aimed to examine the correlations between subjective anxiety states and brain activity in a large sample of SAD patients, during an anxiety-provoking task.Methods: Data were merged from three randomized clinical PET-trials investigating regional cerebral blood flow (rCBF) during a public speaking task pre- and post treatment (SSRI n = 35, placebo n = 37). All participants met diagnostical criteria for SAD. rCBF was assessed with [15O]-labeled water and state anxiety was measured using the Spielberger state anxiety scale (STAI-S). These measures where then correlated using a covariate of interest approach in Statistical Parametric Mapping (SPM2).Results: rCBF and STAI-S scores correlated positively in the left parahippocampal gyrus and amygdala, as well as in the right premotor cortex (area 6). Negative correlations were observed in the left superior frontal gyrus, thalamus, and the right parahippocampal gyrus. Negative correlations were also found bilaterally in the cerebellum.Conclusions: The correlations between clinical anxiety states and brain activity were noted in areas previously demonstrated to be involved in emotional regulation and motor preparedness.
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| 2. |
- Michelgård, Åsa, et al.
(författare)
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Symptom provocation in specific phobia affects the substance P neurokinin-1 receptor systems
- 2007
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Ingår i: Biological Psychiatry. - : Elsevier BV. - 0006-3223 .- 1873-2402. ; 61:8, s. 1002-1006
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Tidskriftsartikel (refereegranskat)abstract
- Background: Animal studies demonstrate that stress and negative affect enhance the release of the neuropeptide substance P (SP), which binds to the neurokinin 1 (NK1) receptor. This positron emission tomography (PET) study evaluated how the activity in the SP-NK1 receptor system in the amygdala was affected by fear provocation in subjects with specific phobia. Methods: Sixteen adult women with DSM-IV-defined specific phobia for either snakes or spiders but not both viewed pictures of feared and non-feared animals while being PET-scanned for 60 min with the highly specific NK1 receptor antagonist [11C]GR205171 as the labeled PET tracer. Results: The uptake of the labeled NK1 receptor antagonist was significantly reduced in the right amygdala during phobic stimulation. In the left amygdala no significant differences were found between phobic and non-phobic conditions. There was a negative correlation in the right, but not left, amygdala between subjective anxiety ratings and NK1 tracer binding. Conclusions: Fear provocation affects the SP-NK1 receptor system in the right amygdala. This reflects reduced NK1 receptor availability during fear and could mirror an increased release of endogenous substance P.
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