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S Rachman - One of the best experts on this subject based on the ideXlab platform.
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the Claustrophobia questionnaire
Journal of Anxiety Disorders, 2001Co-Authors: Adam S Radomsky, Heather K Mcisaac, Dana S Thordarson, S Rachman, Bethany A TeachmanAbstract:Abstract The content and psychometric properties of the Claustrophobia Questionnaire (CLQ) are described. An earlier version of the CLQ was developed to test the hypothesis that Claustrophobia is comprised of two distinct but related fears — the fear of suffocation and the fear of restriction [J. Anxiety Disord. 7 (1993) 281.]. The scale was used to assess patients undergoing the magnetic resonance imaging (MRI) procedure [J. Behav. Med. 21 (1998) 255.] and in participants with panic disorder [J. Abnorm. Psychol. 105 (1996) 146; Taylor, S., Rachman, S., & Radomsky, A. S. (1996). The prediction of panic: a comparison of suffocation false alarm and cognitive theories. Unpublished data.]. On the basis of these studies, we decided to revise and shorten the CLQ, collect normative data, and provide information on the scale's predictive and discriminant validity as well as its internal consistency and test–retest reliability. This was done through a set of four interconnected studies that included psychometric analyses of undergraduate and community adult questionnaire responses and behavioural testing. Results indicate that the CLQ has good predictive and discriminant validity as well as good internal consistency and test–retest reliability. The CLQ appears to be a reliable and sensitive measure of Claustrophobia and its component fears. We encourage the use of the CLQ in a variety of clinical and research applications. The scale is provided in this paper for public use.
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Claustrophobia and the magnetic resonance imaging procedure
Journal of Behavioral Medicine, 1998Co-Authors: Heather K Mcisaac, Dana S Thordarson, Roz Shafran, S Rachman, Gary PooleAbstract:We examined fear induced by the magnetic resonance imaging (MRI) procedure in 80 adult patients who were undergoing the procedure for the first time. Participants completed self-report measures of Claustrophobia, anxiety sensitivity, thoughts about the scan, and pain. Participants were assessed pre- and postscan, and at 1-month follow-up. Twenty-five percent of the participants experienced moderate to severe anx iety during the MRI scan. Prescan scores on the Claustrophobia Questionnaire (CLQ: Rachman and Taylor, 1993) significantly predicted participants' distress during the scan; pain and anxiety sensitivity did not. Furthermore, CLQ scores discriminated between participants who reported panic during the scan and participants who did not report panic. A brief screening instrument consisting of six items from the 29-item CLQ is suggested. This brief screening instrument administered prior to the scan may help identify in advance those people who are most likely to experience claustrophobic fear and, in particular, those who panic during the MRI procedure.
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the reduction of Claustrophobia ii cognitive analyses
Behaviour Research and Therapy, 1993Co-Authors: Roz Shafran, R Booth, S RachmanAbstract:Abstract A clinical experiment comparing methods of fear reduction in Claustrophobia was used as the basis for analysing the relationships between a number of cognitive variables and the reduction of Claustrophobia. Both the number and believability of negative cognitions present were associated with fear reduction and return of fear; this was also found when considering the number of body sensations experienced. High fear and panic were always accompanied by these phenomena whilst zero fear was never reported in the presence of believable cognitions and body sensations. An absence of believable cognitions post-test was accompanied by an absence of Claustrophobia in 10 13 subjects. Specifically, removal of belief in any of the cognitions “I will be trapped”, “I will suffocate” and/or “I will lose control” was associated with removal of belief in all the other cognitions and a dramatic reduction in Claustrophobia. Belief in one of these central cognitions was associated with the maintenance of fear. We conclude that it is possible to conceptualize Claustrophobia as comprising a number of cognitions centred on key thoughts of trappedness, suffocation and loss of control.
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the reduction of Claustrophobia i
Behaviour Research and Therapy, 1992Co-Authors: R Booth, S RachmanAbstract:The purpose of this study was to investigate the process of change during three interventions for Claustrophobia, with particular reference to cognitive changes. Forty-eight participants, recruited from the community through the local media, were randomly assigned to one of four groups: pure exposure, exposure to the sensations of anxiety (interoceptive exposure), modification of negative cognitions, or a control group. All interventions were given over three sessions. The exposure group proved superior to the control on a wide range of measures. In the cognitive group, scores of reported fear and panic, declined significantly. The interoceptive group made some modest gains. An analysis of the timing of fear reduction and of treatment generalization, provides some indications of the mechanism of change.
Adam S Radomsky - One of the best experts on this subject based on the ideXlab platform.
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psychometric properties of the french and english versions of the Claustrophobia questionnaire clq
Journal of Anxiety Disorders, 2006Co-Authors: Adam S Radomsky, Allison J Ouimet, Andrea R Ashbaugh, Matthew R Paradis, Stefanie L Lavoie, Kieron OconnorAbstract:Research suggests that Claustrophobia, defined as the fear of enclosed spaces, may be better conceptualized as two separate, but related fears: (1) the fear of suffocation, and (2) the fear of restriction. The Claustrophobia Questionnaire (CLQ) is a self-report measure designed to assess these two fears. The original English version of the CLQ has demonstrated excellent psychometric properties. The purpose of the present study was to evaluate a French version of the CLQ for use in clinical and research settings and to replicate the psychometric findings of previous investigations of the English CLQ. Language-appropriate versions of the CLQ, as well as self-report measures of phobic, anxious and depressive symptomatology were distributed to undergraduate students at three Montreal, Quebec universities. Results show that the CLQ possesses strong psychometric properties in both languages, and that the English and French versions of the CLQ appear to measure identical constructs. These findings are discussed in terms of proposed applications of the CLQ.
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the Claustrophobia questionnaire
Journal of Anxiety Disorders, 2001Co-Authors: Adam S Radomsky, Heather K Mcisaac, Dana S Thordarson, S Rachman, Bethany A TeachmanAbstract:Abstract The content and psychometric properties of the Claustrophobia Questionnaire (CLQ) are described. An earlier version of the CLQ was developed to test the hypothesis that Claustrophobia is comprised of two distinct but related fears — the fear of suffocation and the fear of restriction [J. Anxiety Disord. 7 (1993) 281.]. The scale was used to assess patients undergoing the magnetic resonance imaging (MRI) procedure [J. Behav. Med. 21 (1998) 255.] and in participants with panic disorder [J. Abnorm. Psychol. 105 (1996) 146; Taylor, S., Rachman, S., & Radomsky, A. S. (1996). The prediction of panic: a comparison of suffocation false alarm and cognitive theories. Unpublished data.]. On the basis of these studies, we decided to revise and shorten the CLQ, collect normative data, and provide information on the scale's predictive and discriminant validity as well as its internal consistency and test–retest reliability. This was done through a set of four interconnected studies that included psychometric analyses of undergraduate and community adult questionnaire responses and behavioural testing. Results indicate that the CLQ has good predictive and discriminant validity as well as good internal consistency and test–retest reliability. The CLQ appears to be a reliable and sensitive measure of Claustrophobia and its component fears. We encourage the use of the CLQ in a variety of clinical and research applications. The scale is provided in this paper for public use.
Marc Dewey - One of the best experts on this subject based on the ideXlab platform.
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analysis and prediction of Claustrophobia during mr imaging with the Claustrophobia questionnaire an observational prospective 18 month single center study of 6500 patients
Radiology, 2017Co-Authors: Adriane Napp, Judith Enders, Robert Roehle, Gerd Diederichs, Matthias Rief, Elke Zimmermann, Peter Martus, Marc DeweyAbstract:The Claustrophobia questionnaire is a suitable tool to screen for absence of a subsequent claustrophobic event during MR imaging; furthermore, although it is possible to identify patients with a considerable risk of Claustrophobia, prediction in individual patients is not possible.
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Claustrophobia during magnetic resonance imaging cohort study in over 55 000 patients
Journal of Magnetic Resonance Imaging, 2007Co-Authors: Marc Dewey, Tania Schink, Charles F DeweyAbstract:Purpose To evaluate whether MR scanners with acoustic noise reduction and a short magnetic bore reduce the rate of claustrophobic reactions. Materials and Methods We performed a cohort study in an outpatient setting, enrolling a total of 55,734 consecutive patients referred for MRI of any part of the body based on a clinical indication. Imaging was performed using a conventional MR scanner (42,998 patients) and a recently developed MR scanner (12,736 patients) with 97% acoustic noise reduction and a short bore. Multiple logistic regression analysis was used to adjust for the nonrandomized design. Results In addition to those undergoing head-first examinations, female and middle-aged patients were significantly more likely to develop Claustrophobia in the logistic regression analysis (P < 0.001). The rate of claustrophobic reactions was significantly lower with the recent MR scanner (0.7%; 95% confidence interval [CI]: 0.6–0.9%) than with the conventional scanner (2.1%; 95% CI, 2.0–2.3%; P < 0.001) with an adjusted odds ratio (OR) of 3.1 (95% CI, 2.5–3.9) and a number needed to treat of 72 (95% CI, 63–85). Conclusion The incidence of Claustrophobia may be reduced by a factor of 3 when recently-developed MR scanners are used. J. Magn. Reson. Imaging 2007;26:1322–1327. © 2007 Wiley-Liss, Inc.
Francis A Longstaff - One of the best experts on this subject based on the ideXlab platform.
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portfolio Claustrophobia asset pricing in markets with illiquid assets
The American Economic Review, 2009Co-Authors: Francis A LongstaffAbstract:Many classes of assets are illiquid or nonmarketable in that they cannot always be traded immediately. Thus, a portfolio position in these becomes at least temporarily irreversible. We study the asset-pricing implications of this type of illiquidity in an exchange economy with heterogeneous agents. In this market, one asset is always liquid. The other asset can be traded initially, but then not again until after a "blackout" period. Illiquidity has a dramatic effect. Agents abandon diversification and choose polarized portfolios instead. The value of liquidity can represent a large portion of the equilibrium price of an asset. (JEL G11, G12)
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financial Claustrophobia asset pricing in illiquid markets
National Bureau of Economic Research, 2004Co-Authors: Francis A LongstaffAbstract:There are many examples of markets where an agent who wants to get out of an investment position quickly may find himself trapped and forced to remain in that position because of a lack of liquidity. What are the asset-pricing implications when agents cannot always buy and sell assets immediately? We study this issue in a multi-asset exchange economy with heterogeneous agents. In this model, agents can trade initially, but then cannot trade again until after a trading blackout' period. The more liquid the market, the sooner agents can trade again. Faced with illiquidity, agents abandon diversification and choose highly polarized portfolios. Risky assets are held primarily by the less-patient short-horizon agents in the economy. Polarization causes the usual risk-return tradeo. to break down and an asset's price may have more to do with the demographics of who owns it than with the riskiness of its cash flows. Risky assets are generally more valuable in an illiquid market than in a liquid market. Market illiquidity can also have large effects on the equity premium.
Jason D Warren - One of the best experts on this subject based on the ideXlab platform.
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the mind is its own place amelioration of Claustrophobia in semantic dementia
Behavioural Neurology, 2014Co-Authors: Camilla N Clark, Phillip D Fletcher, Alberto Cifelli, Laura E Downey, Hannah L Golden, Rajith De Silva, Jason D WarrenAbstract:Phobias are among the few intensely fearful experiences we regularly have in our everyday lives, yet the brain basis of phobic responses remains incompletely understood. Here we describe the case of a 71-year-old patient with a typical clinicoanatomical syndrome of semantic dementia led by selective (predominantly right-sided) temporal lobe atrophy, who showed striking amelioration of previously disabling Claustrophobia following onset of her cognitive syndrome. We interpret our patient’s newfound fearlessness as an interaction of damaged limbic and autonomic responsivity with loss of the cognitive meaning of previously threatening situations. This case has implications for our understanding of brain network disintegration in semantic dementia and the neurocognitive basis of phobias more generally.
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the mind is its own place amelioration of Claustrophobia in a patient with semantic dementia
Journal of Neurology Neurosurgery and Psychiatry, 2013Co-Authors: Camilla Clarke, Phillip D Fletcher, Alberto Cifelli, Jason D WarrenAbstract:Specific phobia is defined as marked, persistent and excessive or unreasonable fear when in the presence of, or when anticipating an encounter with, a specific object or situation. 1 Here we describe amelioration of one common and disabling example, Claustrophobia, following the onset of semantic dementia. Our patient had a clinical diagnosis of Claustrophobia dating from her 20s and severe enough to cause her difficulties in daily life. She had habitually avoided lifts, windowless rooms, train travel and flying on account of her intense fear of being enclosed. At the age of 61, she developed a typical syndrome of semantic dementia led by progressive loss of facial recognition, anomic aphasia with loss of verbal and nonverbal knowledge and characteristic asymmetric (predominantly right sided) anterior temporal lobe atrophy on brain MRI. Around 7 years after onset of first symptoms her family reported that her previously severe Claustrophobia had essentially disappeared: she would now enter small rooms without evident distress and happily participated in a longitudinal research study involving regular MRI scans. Specific phobias are thought to be mediated neuroanatomically via limbic and paralimbic circuitry, including the amygdala, anterior cingulate and insula. 2 These regions are all targeted in semantic dementia, while altered fronto–limbic connectivity has been described in frontotemporal lobar degeneration. 3 Our patient9s newfound fearlessness may reflect an interaction of damaged limbic and autonomic responsivity with loss of the cognitive meaning of previously threatening situations. More broadly, her case illustrates how the brain constructs a private model of the world and invests this with emotional significance, and how this process can be modulated by pathological mental states: as recognised long ago by John Milton, and others.