Sample entropy of ECG time series of fearful flyers: preliminary results

Nonlinear Dynamics Psychol Life Sci. 2006 Jul;10(3):301-18. Sample entropy of ECG time series of fearful flyers: preliminary results. Bornas X, Llabrés J, Noguera M, Pérez A.

Research within the framework of the nonlinear dynamical systems (NDS) in the field of anxiety disorders has shown that greater irregularity/complexity appears in the output from healthy systems. In this study we measured the Heart rate variability (HRV) and the sample sntropy (SampEn) of the ECG mV time series of fearful flyers (N = 15) and a matched control group (N = 15) when confronted with three combinations of feared stimuli (pictures, sounds, and pictures with sounds) as well as relaxing stimuli (pictures and sounds). Fearful flyers had lower SampEn than controls in all conditions, including baseline. Non-phobics showed significant entropy decreases from baseline in two out of three exposure conditions. No differences on HRV were found between groups, and HRV was not sensitive to condition changes. The main finding of the study is that the SampEn calculated on very short ECG mV recordings (10 to 60 seconds, easy to obtain in clinical settings) may be a useful diagnostic measure since it can distinguish fearful from non-fearful flyers.

Fear induced complexity loss in the electrocardiogram of flight phobics: A multiscale entropy analysis

Xavier Bornas, Jordi Llabres, Miquel Noguera, Ana M Lopez, Joan Miquel Gelabert, Irene Vila, Fear induced complexity loss in the electrocardiogram of flight phobics: A multiscale entropy analysis, Biological Psychology, Volume 73, Issue 3, October 2006, Pages 272-279, ISSN 0301-0511, DOI: 10.1016/j.biopsycho.2006.05.004.

In this study we explored the changes in the variability and complexity of the electrocardiogram (ECG) of flight phobics (N = 61) and a matched non-phobic control group (N = 58) when they performed a paced breathing task and were exposed to flight related stimuli. Lower complexity/entropy values were expected in phobics as compared to controls. The phobic system complexity as well as the heart rate variability (HRV) were expected to be reduced by the exposure to fearful stimuli. The multiscale entropy (MSE) analysis revealed lower entropy values in phobics during paced breathing and exposure, and a complexity loss was observed in phobics during exposure to threatening situations. The expected HRV decreases were not found in this study. The discussion is focused on the distinction between variability and complexity measures of the cardiac output, and on the usefulness of the MSE analysis in the field of anxiety disorders.

Looking at the heart of low and high heart rate variability fearful flyers: self-reported anxiety when confronting feared stimuli

Xavier Bornas, Jordi Llabres, Miquel Noguera, Ana M[feminine ordinal indicator] Lopez, Francesca Barcelo, Miquel Tortella-Feliu, Miquel Angel Fullana, Looking at the heart of low and high heart rate variability fearful flyers: self-reported anxiety when confronting feared stimuli, Biological Psychology, Volume 70, Issue 3, December 2005, Pages 182-187, ISSN 0301-0511, DOI: 10.1016/j.biopsycho.2005.01.002.

Previous research has shown that phobic subjects with low heart rate variability (HRV) are less able to inhibit an inappropriate response when confronted with threatening words compared to phobic subjects with high HRV [Johnsen, B.H., Thayer, J.F., Laberg, J.C., Wormnes, B., Raadal, M., Skaret, E., et al., 2003. Attentional and physiological characteristics of patients with dental anxiety. Journal of Anxiety Disorders, 17, 75-87]. The aim of this study was to evaluate changes in self-reported anxiety when low HRV and high HRV fearful flyers (N = 15) and a matched control group (N = 15) were exposed to flight-related pictures, flight-related sounds or both pictures and sounds. We hypothesized that sounds would be crucial to evoke fear. Also, low HRV fearful flyers were expected to report higher anxiety than high HRV fearful flyers assuming anxiety as their inappropriate response. Decreases on HRV measures were also predicted for a subgroup of phobic participants (N = 10) when confronted with the feared stimuli. Our data supported the hypothesis that sounds are crucial in this kind of phobia. Low HRV fearful flyers reported higher anxiety than high HRV fearful flyers in two out of three aversive conditions. The predicted HRV decreases were not found in this study. Results are discussed in the context of avoidance of exposure-based treatments.

¿Caos en el electrocardiograma de estudiantes con miedo a volar? Un análisis de no linealidad

International Journal of Clinical and Health Psychology, 2005, 5, 273-284 ¿Caos en el electrocardiograma de estudiantes con miedo a volar? Un análisis de no linealidad Jordi Llabrés, Xavier Bornas, Miquel Noguera, Ana María López y Francesca Barceló

Chaos theory provides a new way to analyze the psychophysiological functioning of anxiety disordered people. However, in order to apply any of the nonlinear analysis techniques, nonlinearity tests must be performed and nonlinearity must be found in the psychophysiological signal. In this experimental study we use the surrogate data method to analyze the nonlinearity of the ECG time series of students with and without fear of flying under several stressing conditions. The prediction errors of the surrogate data were found to be much higher than the prediction errors of the ECG signals (p < .05) in all the experimental conditions as well as during the baseline period. We conclude that nonlinear properties are in fact in the ECGs of the participants, and therefore it would be possible to analyze these signals with nonlinear techniques to get knowledge about their comnplexity, entropy, regularity, and so on.

Self-implication and heart rate variability during simulated exposure to flight-related stimuli

Anxiety, Stress & Coping. Volume 17, Issue 4, 2004, 331-339. Self-implication and heart rate variability during simulated exposure to flight-related stimuli. DOI:10.1080/10615800512331328777. Xavier Bornas, Jordi Llabrés, Miquel Noguera, Ana M. López, Francesca Barceló, Miquel Tortella-Feliu & Miquel Àngel Fullana

In the present study, the relationship between self-implication during simulated exposure to feared stimuli and Heart Rate Variability (HRV) was explored within the framework of the dynamical systems model of emotion regulation proposed by Thayer and Lane (Thayer, J.F., and Lane, R.D. (2000). A model of neurovisceral integration in emotion regulation and dysregulation. Journal of Affective Disorders, 61, 201–216.). An analogue sample of flight phobics (n=15) and a matched non-phobic control group (n=15) were presented with flight-related pictures, flight-related sounds or flight-related pictures and sounds. Significant differences on self-implication during exposure to flight-related sounds were found between low and high HRV fearful flyers, the former being more self-implied. However, the expected HRV decreases in the phobic participants exposed to feared stimuli were not found. These results emphasize the need to distinguish between high and low HRV fearful flyers in order to make a better use of the simulated exposure treatments.

Estilo de afrontamiento y resultados del tratamiento de exposición en sujetos con fobia a volar

International Journal of Clinical and Health Psychology, 2003, 3, 477-487. Estilo de afrontamiento y resultados del tratamiento de exposición en sujetos con fobia a volar. Jordi Miró, Gloria García de la Banda, M. Angeles Martínez-Abascal, Miquel Tortella-Feliu, Xavier Bornas y Jordi Llabrés (Universitat de les Illes Balears, España)

El objetivo de este trabajo cuasi-experimental es doble. Por una parte, se trata de estudiar si el estilo de afrontamiento de los pacientes (buscadores y evitadores de información; monitoring y blunting ) está relacionado con los efectos de la terapia de exposición; por otra, examinar si este estilo está relacionado con sesgos de atención. Aplicamos el CAFFT (Computer Assisted Fear of Flying Treatment), esto es, un programa de exposición asistido por ordenador, a una muestra de 17 personas con miedo a volar en avión. Para la evaluación del estilo de afrontamiento empleamos la versión española de la Miller Behavioural Style Scale, mientras que los sesgos de atención fueron valorados mediante el test Stroop . Los resultados muestran que el tratamiento fue efectivo, y si bien no detectan relación con el estilo de afrontamiento, se observa que el estilo de búsqueda de información (por ejemplo, monitoring ) está asociado con mayores trastornos antes del tratamiento, aunque éstos desaparecen tras el mismo. Nuestros datos también muestran una relación estadísticamente significativa entre sesgo de atención y estilo de afrontamiento.

Clinical Usefulness of a Simulated Exposure Treatment for Fear of Flying

Xavier Bornas, Miquel Tortella-Feliu, Jordi Llabrés, Andreas Mühlberger, Paul Pauli, and Francesca Barceló (2002) Clinical Usefulness of a Simulated Exposure Treatment for Fear of Flying International Journal of Clinical and Health Psychology, 2002, 2, 247-262

The aim of this paper is to assess the clinical usefulness of a computer assisted exposure treatment for fear of flying, which already proved to be effective in laboratory, controlled conditions. Two studies, one in Mallorca (S1, N= 12) and the other one in Germany (S2, N=8), were conducted. Patients were recruited using advertisements in the airport (S1) or in local newspapers (S2), and they were individually treated. Data on fear of flying were collected before treatment, after computer assisted exposure, and after a post-treatment actual flight. Several results corroborated the clinical usefulness of the treatment: (a) effective exposure time was quite similar in both studies; (b) nineteen out of 20 patients completed treatment and took the actual flight; (c) the main fear reductions were found after computer exposure and before taking the flight; and (d) therapeutic changes were clinically significant in most cases: 91.7% of patients in S1, and 87.5% in S2 improved or recovered. We conclude that the clear structure of the computer assisted program facilitates its application in very different settings. Moreover, therapists need only little training to use the program succesfully.

 

Computer-Assisted Exposure Treatment for Flight Phobia: a Controlled Study

Psychotherapy Research. Volume 11, Issue 3, 2001, 259-273. Computer-Assisted Exposure Treatment for Flight Phobia: a Controlled Study. DOI:10.1080/713663983. X. Bornas, M. Tortella-Feliu, J. Llabrés & M.A. Fullana

This study examines the efficacy of computer-assisted exposure (CAE) treatment in helping to overcome flight phobia and analyzes the role of relaxation and information-related components in the reduction of fear. Fifty flight phobics were randomly assigned to 1 of 3 methods of treatment: (a) CAE; (b) a multicomponent method of treatment of information, relaxation, and CAE (IRCAE); and (c) waiting list control treatment. At the end of the treatment, an actual flight was chartered. The results showed that the first 2 methods of treatments were more effective than the waiting list control treatment. The CAE group showed the greatest reduction in fear. According to data from the IRCAE group, no reduction in flight phobia was observed after the information-relaxation phase. Follow-up data showed that improvements in anxiety self-assessment rates remained constant.

Computer-assisted therapy in the treatment of flight phobia: A case report

Xavier Bornas, Miquel A. Fullana, Miquel Tortella-Feliu, Jordi Llabres, Gloria Garcia de la Banda, Computer-assisted therapy in the treatment of flight phobia: A case report, Cognitive and Behavioral Practice, Volume 8, Issue 3, Summer 2001, Pages 234-240, ISSN 1077-7229, DOI: 10.1016/S1077-7229(01)80058-4

The efficacy of computer-assisted exposure (CAE) therapy for the treatment of flight phobia was examined. The subject was a 34-year-old man with severe fear and almost complete avoidance of flying. Six 50-minute CAE sessions and two 20-minute booster sessions were conducted over a period of 1 month. All self-reported measures of the fear of flying decreased following CAE, and before the subject took a one-hour flight with minimal distress. A follow-up after 6 months revealed that he had flown three times without anxiety. The implications of CAE for treatment of flight phobia are discussed.

La mejora de los hábitos de escritura a través del modelado por ordenador : un estudio experimental en preescolares

Anales de psicología, 2000, 16(1), 41-48.La mejora de los hábitos de escritura a través del modelado por ordenador : un estudio experimental en preescolares. Xavier Bornas, Mateu Servera Barceló, Jordi Llabrés, Isabel Matas. DOI: 0212-6559

El presente trabajo evalúa la eficacia del programa VISPRO.Grafías para el aprendizaje de la escritura de letras en sus fases iniciales. Se evaluó la calidad de ejecución (número de errores) de diez letras en un curso de preescolar (n=27). Los sujetos con mejor ejecución fueron asignados a un grupo que sirvió de control (n=7). Los demás se asignaron aleatoriamente a los dos grupos experimentales A y B (n=10). La intervención consistió en diez sesiones de diez minutos para cada niño con el programa informático para mejorar la escritura de cinco de dichas letras. Después de aplicar la intervención sólo al grupo A se realizó la segunda evaluación de todos los sujetos. El programa se aplicó a continuación al grupo B y se realizó una tercera evaluación. Los resultados muestran una significativa reducción del número de errores cometidos por los sujetos tras recibir la intervención. Ambos grupos (A y B) llegan a equipararse al C al final del programa. Además, el tratamiento consigue efectos superiores a los producidos por el trabajo cotidiano en la clase.