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| 2. |
- Critchley, Hugo D, et al.
(författare)
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Neural systems supporting interoceptive awareness.
- 2004
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Ingår i: Nat Neurosci. - : Springer Science and Business Media LLC. - 1097-6256 .- 1546-1726. ; 7:2, s. 189-95
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Tidskriftsartikel (refereegranskat)abstract
- Influential theories of human emotion argue that subjective feeling states involve representation of bodily responses elicited by emotional events. Within this framework, individual differences in intensity of emotional experience reflect variation in sensitivity to internal bodily responses. We measured regional brain activity by functional magnetic resonance imaging (fMRI) during an interoceptive task wherein subjects judged the timing of their own heartbeats. We observed enhanced activity in insula, somatomotor and cingulate cortices. In right anterior insular/opercular cortex, neural activity predicted subjects' accuracy in the heartbeat detection task. Furthermore, local gray matter volume in the same region correlated with both interoceptive accuracy and subjective ratings of visceral awareness. Indices of negative emotional experience correlated with interoceptive accuracy across subjects. These findings indicate that right anterior insula supports a representation of visceral responses accessible to awareness, providing a substrate for subjective feeling states.
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| 3. |
- Kompus, Kristiina, 1983-, et al.
(författare)
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Distinct control networks for cognition and emotion in the prefrontal cortex
- 2009
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Ingår i: Neuroscience Letters. - : Elsevier BV. - 0304-3940 .- 1872-7972. ; 467:2, s. 76-80
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Tidskriftsartikel (refereegranskat)abstract
- The activation of dorsolateral prefrontal cortex (dlPFC) has been suggested to reflect the engagement of a control mechanism for top-down biasing of context processing in resource-demanding memory tasks. Here we tested the hypothesis that the dlPFC subserves a similar function also in attention and emotion tasks. 18 healthy young adults were tested in a functional magnetic resonance imaging (fMRI) study where the demands for context processing were manipulated in three different cognitive domains: auditory attention, episodic retrieval, and emotion regulation. We found that the right dlPFC was jointly sensitive to increased cognitive demands in the attention and memory tasks. By contrast, increased demands in the emotion task (reappraisal) were associated with increased activity in ventromedial PFC along with decreased amygdala activity. Our findings of divergent prefrontal control networks for cognitive and emotional control extend previous separations of cognition and emotion in the anterior cingulate cortex.
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| 5. |
- Lonsdorf, Tina B, et al.
(författare)
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The COMTval158met polymorphism is associated with symptom relief during exposure-based cognitive-behavioral treatment in panic disorder
- 2010
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Ingår i: BMC Psychiatry. - : BioMed Central. - 1471-244X. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Background: Cognitive behavioral therapy (CBT) represents a learning process leading to symptom relief and resulting in long-term changes in behavior. CBT for panic disorder is based on exposure and exposure-based processes can be studied in the laboratory as extinction of experimentally acquired fear responses. We have recently demonstrated that the ability to extinguish learned fear responses is associated with a functional genetic polymorphism (COMTval158met) in the COMT gene and this study was aimed at transferring the experimental results on the COMTval158met polymorphism on extinction into a clinical setting. Methods: We tested a possible effect of the COMTval158met polymorphism on the efficacy of CBT, in particular exposure-based treatment modules, in a sample of 69 panic disorder patients. Results: We present evidence that panic patients with the COMTval158met met/met genotype may profit less from (exposure-based) CBT treatment methods as compared to patients carrying at least one val-allele. No association was found with the 5-HTTLPR/rs25531 genotypes which is presented as additional material. Conclusions: We were thus able to transfer findings on the effect of the COMTval158met polymorphism from an experimental extinction study obtained using healthy subjects to a clinical setting. Furthermore patients carrying a COMT val-allele tend to report more anxiety and more depression symptoms as compared to those with the met/met genotype. Limitations of the study as well as possible clinical implications are discussed.
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| 6. |
- Lonsdorf, Tina B, et al.
(författare)
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The symptomatic profile of panic disorder is shaped by the 5-HTTLPR polymorphism
- 2009
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Ingår i: Progress in Neuro-psychopharmacology and Biological Psychiatry. - : Elsevier BV. - 0278-5846 .- 1878-4216. ; 33:8, s. 1479-1483
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Forskningsöversikt (refereegranskat)abstract
- The short allele of a functional polymorphism (5-HTTLPR) in the serotonin transporter (5-HTT) promoter is associated with reduced serotonin transporter expression, lower in vivo 5-HTT binding, higher neuroticism and amygdala reactivity as well as facilitated fear conditioning and is a candidate variant for panic disorder. However, case-control studies have consistently failed to show an association between 5-HTTLPR and panic disorder. As psychiatric disorders are broadly defined phenotypes merging different symptoms to syndromes, they may not be very well suited for genetic association studies. An alternative approach is to measure symptoms along continuous symptom dimensions which may more appropriately reflect their biological underpinnings and may reveal subpopulations within clinical diagnostic groups. We recorded the symptomatic profile in 73 in panic disorder patients using observer-rated instruments (Panic Disorder Severity Scale, PDSS; Montgomery-Asberg Depression Rating Scale, MADRS) and hypothesized more severe symptoms in patients carrying the 5-HTTLPR s-allele. We observed a strong association between bi- and triallelic 5-HTTLPR polymorphisms and the symptomatic profile. Carriers of the 5-HTTLPR s-allele suffered from most severe panic and depressive symptoms. Our data highlight the importance of defining appropriate phenotypes for psychiatric genetic studies and demonstrate that the 5-HTTLPR genotype may be related to the symptomatic profiles rather than to the vulnerability to develop panic disorder.
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| 7. |
- Wiens, Stefan, et al.
(författare)
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Keeping it short : A comparison of methods for brief picture presentation.
- 2004
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Ingår i: Psychol Sci. - : SAGE Publications. - 0956-7976 .- 1467-9280. ; 15:4, s. 282-5
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Tidskriftsartikel (refereegranskat)abstract
- Research has shown that backward masking is apowerful tool for studying unconscious mental processes.Whereas studies have traditionally presented stimuli usingcathode-ray tube (CRT) monitors or mechanical shutters togetherwith slide projectors, recent studies (mainly in functionalmagnetic resonance imaging, fMRI) have begun to use methodsbased on liquid crystal displays (LCDs) and thin-film transistor(TFT) technology. However, because of differences in technology,all methods may not be equally suited for masking. Whenmethods were compared for their accuracy in presenting picturesat short durations, LCD and TFT presentations had pooraccuracy, but shutter and CRT presentations had better accuracy.Because CRTs interfere with the imaging process in fMRI,we recommend the use of mechanical shutters. However, ourresults may not generally apply to all displays, so we adviseresearchers to validate the presentation parameters of theirdisplays. The procedure described here may be useful for thatpurpose.
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| 8. |
- Wiens, Stefan, et al.
(författare)
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Visual masking in magnetic resonance imaging.
- 2005
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Ingår i: Neuroimage. - : Elsevier BV. - 1053-8119. ; 27:2, s. 465-7
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Tidskriftsartikel (refereegranskat)abstract
- When a brief target picture is followed by another picture (mask),people often report that they are not consciously aware of the target.Thus, visual masking can be used to manipulate perceptual awarenessof target pictures. To avoid interference with magnetic resonanceimaging, pictures have been presented on liquid crystal device (LCD)and thin film transistor (TFT) projectors that were placed outside of thescanner room. However, we found that display devices with LCD/TFTtechnology exhibit poor accuracy in presenting pictures at briefdurations [Wiens, S., Fransson, P., Dietrich, T., Lohmann, P., Ingvar,M., O¨ hman, A., 2004. Keeping it short: A comparison of methods forbrief picture presentation. Psychological Science, 15, 282–285]. In thispaper, we present a reliable and valid masking procedure involving twoLCD/TFT projectors in combination with mechanical shutters. BecauseLCD/TFT projectors present pictures in steady state at longer durations(e.g., after 70 ms), picture presentation is more ecologically valid thanfor common cathode ray tube (CRT) monitors that present pictures inmultiples of refresh cycles. Also, because picture presentation withmechanical shutters is instantaneous and reliable in terms of onset, risetime, and duration, shutters can be used to control picture durationsprecisely in steps of milliseconds. In this paper, we also discuss risks forconfounding effects from unreliable picture presentations in masking.Our findings and arguments recommend the use of mechanical shuttersin front of LCD/TFT projectors in imaging studies of visual masking.
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