Fear responses to mock magnetic resonance imaging among college students: toward a prototype experiment

The impact of MRI scanner environment on perceptual decision-making

Despite the widespread use of functional magnetic resonance imaging (fMRI), few studies have addressed scanner effects on performance. The studies that have examined this question show a wide variety of results. In this article we report analyses of three experiments in which participants performed a perceptual decision-making task both in a traditional setting as well as inside an MRI scanner. The results consistently show that response times increase inside the scanner. Error rates also increase, but to a lesser extent. To reveal the underlying mechanisms that drive the behavioral changes when performing a task inside the MRI scanner, the data were analyzed using the linear ballistic accumulator model of decision-making. These analyses show that, in the scanner, participants exhibit a slow down of the motor component of the response and have less attentional focus on the task. However, the balance between focus and motor slowing depends on the specific task requirements.

Within and between session changes in subjective and neuroendocrine stress parameters during magnetic resonance imaging: A controlled scanner training study

Accumulating evidence suggests that the magnetic resonance imaging (MRI) scanner can act as a stressor, eliciting subjective and neuroendocrine stress responses. Approaches to familiarize subjects with the scanner could help minimizing unintended effects on neural activation patterns of interest. Controlled studies on the effects of a scanner training are however missing. Using a comparative design, we analyzed within- and between session changes in subjective and neuroendocrine stress parameters in 63 healthy, scanner-naïve adults who participated in a two-day training protocol in an MRI, mock, or lab environment. A habituation task was used to assess within-session changes in subjective and neuroendocrine (cortisol) stress parameters; between-session changes were indicated by differences between days. MRI and mock, but not lab training were successful in reducing subjective distress towards the scanner. In contrast, cortisol reactivity towards the training environment generally increased during day 2, and the percentage of cortisol responders particularly rose in the mock and MRI groups. Within-session habituation of subjective arousal and anxiety was observed during both days and irrespective of training condition. Present findings demonstrate that training in a scanner environment successfully reduces subjective distress, but may also induce sensitization of endocrine stress levels during repeated scanning. Subjective distress can further be stabilized by acclimating subjects to the environment prior to the MRI assessment, including a short habituation phase into the assessment protocol. If replicated, present findings should be considered by researchers employing repeated measurement designs where subjects are exposed to a scanner more than once.

(Don't) panic in the scanner! How panic patients with agoraphobia experience a functional magnetic resonance imaging session

Although functional magnetic resonance imaging (fMRI) has gained increasing importance in investigating neural substrates of anxiety disorders, less is known about the stress eliciting properties of the scanner environment itself. The aim of the study was to investigate feasibility, self-reported distress and anxiety management strategies during an fMRI experiment in a comprehensive sample of patients with panic disorder and agoraphobia (PD/AG). Within the national research network PANIC-NET, n=89 patients and n=90 controls participated in a multicenter fMRI study. Subjects completed a retrospective questionnaire on self-reported distress, including a habituation profile and exploratory questions about helpful strategies. Drop-out rates and fMRI quality parameters were employed as markers of study feasibility. Different anxiety measures were used to identify patients particularly vulnerable to increased scanner anxiety and impaired data quality. Three (3.5%) patients terminated the session prematurely. While drop-out rates were comparable for patients and controls, data quality was moderately impaired in patients. Distress was significantly elevated in patients compared to controls; claustrophobic anxiety was furthermore associated with pronounced distress and lower fMRI data quality in patients. Patients reported helpful strategies, including motivational factors and cognitive coping strategies. The feasibility of large-scale fMRI studies on PD/AG patients could be proved. Study designs should nevertheless acknowledge that the MRI setting may enhance stress reactions. Future studies are needed to investigate the relationship between self-reported distress and fMRI data in patient groups that are subject to neuroimaging research.

The Dutch Claustrophobia Questionnaire: psychometric properties and predictive validity

Fear of suffocation and fear of restriction are thought to underlie claustrophobia and can be assessed with the Claustrophobia Questionnaire (CLQ; Radomsky et al., 2001). A first study tested the psychometric properties of a Dutch version of the CLQ. Students (N=363) completed a Dutch translation of the CLQ and a set of other questionnaires assessing other specific fears, anxiety or depression. Results confirmed the two-factor structure and showed that the Dutch version of the CLQ has good psychometric properties. A second study tested the predictive validity of the Dutch CLQ. Participants (N=23) were exposed each to nine claustrophobic situations with elements of suffocation, restriction or both. The Dutch CLQ was found to be a significant predictor of fear and respiratory reactivity during claustrophobic exposure. It can be concluded that the Dutch version of the CLQ is a reliable and valid instrument to assess claustrophobic fear.

Reviewing the process of preparing children for MRI

BACKGROUND

MRI is a common medical imaging investigation. Patients, including young children, can be required to keep still for up to 60 min for the study to be completed successfully. Children often find the confined space, noise, need to lie still and possibility of intravenous administration of contrast agent anxiety-provoking and sometimes so distressing that they are unable to cope and require general anaesthesia.

OBJECTIVE

A practice MRI intervention was introduced at the Royal Children's Hospital in Melbourne, Australia. The program is conducted by educational play therapists in conjunction with the Department of Medical Imaging. This study explored the effectiveness of this intervention.

MATERIALS AND METHODS

The intervention was conducted in a practice MRI unit devoid of magnets. Data were collected as a clinical audit with respect to age, gender, times of scans, position in bore, diagnostic scans and movement artefact. Epidata and Stata were used to analyze the data.

RESULTS

A total of 291 children were included; their ages ranged from 3 years 7 months to 17 years (mean 7.9 years), and 48.8% were male. Of the 291 children, 218 (74.9%) were considered a pass at practice, 35 (12 %) were considered borderline pass, and diagnostic images were obtained from 218 (96%) of those children who went onto a clinical MRI.

CONCLUSION

We conclude that practice MRI intervention facilitated by educational play therapists is a useful intervention in supporting children to cope with MRI without general anaesthesia.

Component fears of claustrophobia associated with mock magnetic resonance imaging

A conceptualization of claustrophobia [Rachman, S., & Taylor, S. (1993). Analyses of claustrophobia. Journal of Anxiety Disorders, 7, 281-291] was evaluated in the context of magnetic resonance imaging. One hundred eleven students responded to questionnaires that quantified fear of suffocation, fear of restriction, and sensitivity to anxiety symptoms. Sixty-four of them were then exposed to a mock magnetic resonance imaging assessment; maximum subjective fear during the mock assessment was self-reported, behavioral reactions to the mock assessment were characterized, and heart rates before and during the assessment were recorded. Scores for fear of suffocation, fear of restriction, and anxiety sensitivity were used to predict subjective, behavioral, and cardiac fear. Subjective fear during the mock assessment was predicted by fears of suffocation and public anxiousness. Behavioral fear (escape/avoidance) was predicted by fears of restriction and suffocation, and sensitivity to symptoms related to suffocation. Cardiac fear was predicted by fear of public anxiousness. The criterion variance predicted was impressive, clearly sufficient to legitimize both the research preparation and the conceptualization of claustrophobia that was evaluated.

Practice MRI: reducing the need for sedation and general anaesthesia in children undergoing MRI

The aim of this study was to evaluate the effectiveness of a practice magnetic resonance unit, in preparing children to undergo magnetic resonance procedures without general anaesthesia (GA) or sedation. The records of children who attended the practice MRI between February 2002 and April 2004 were retrospectively reviewed. Each record was assessed as to whether the child had passed or failed the practice MRI intervention. Those children who were considered to have passed and were proceeded to a clinical non-GA MRI had the report of the clinical scan reviewed. If the scan had been reported as non-diagnostic because of movement artefact it was classified as a failed scan, otherwise it was considered a pass. One hundred and thirty-four children undertook a practice MRI (age range 4.1-16.1 years, median age 7.7 years, 47% boys) and 120/134 (90%) passed the practice session. In all, 117/120 (98%) subsequently had a clinical non-GA MRI and 110/117 (94%) passed (median age 7.8 years, 47% boys). Preparation is a safe and effective method to reduce the need for sedation and GA in children undergoing a clinical MRI scan. It provides a positive medical experience for children, parents and staff, and results in cost savings for the hospital.