Percentage of nonoverlapping corrected data

The present study proposes a modification in one of the most frequently applied effect size procedures in single-case data analysis the percent of nonoverlapping data. In contrast to other techniques, the calculus and interpretation of this procedure is straightforward and it can be easily complemented by visual inspection of the graphed data. Although the percent of nonoverlapping data has been found to perform reasonably well in N = 1 data, the magnitude of effect estimates it yields can be distorted by trend and autocorrelation. Therefore, the data correction procedure focuses on removing the baseline trend from data prior to estimating the change produced in the behavior due to intervention. A simulation study is carried out in order to compare the original and the modified procedures in several experimental conditions. The results suggest that the new proposal is unaffected by trend and autocorrelation and can be used in case of unstable baselines and sequentially related measurements.

Estimating slope and level change in N=1 designs

The current study proposes a new procedure for separately estimating slope change and level change between two adjacent phases in single-case designs. The procedure eliminates baseline trend from the whole data series prior to assessing treatment effectiveness. The steps necessary to obtain the estimates are presented in detail, explained, and illustrated. A simulation study is carried out to explore the bias and precision of the estimators and compare them to an analytical procedure matching the data simulation model. The experimental conditions include two data generation models, several degrees of serial dependence, trend, level and/or slope change. The results suggest that the level and slope change estimates provided by the procedure are unbiased for all levels of serial dependence tested and trend is effectively controlled for. The efficiency of the slope change estimator is acceptable, whereas the variance of the level change estimator may be problematic for highly negatively autocorrelated data series.

Terapia sistémica de pareja en la depresión: un estudio de caso único

En este estudio de caso único se presenta el tratamiento de una mujer diagnosticada de depresión mayor con terapia sistémica de pareja. Esta modalidad de terapia supone la inclusión de la pareja en todas las sesiones de tratamiento, en las que se trabaja con ambos de forma conjunta. A medida que avanza la terapia se van explicitando los significados relacionales de los síntomas y las dificultades de relación, y se trabaja de forma conjunta para remediarlas. El proceso terapéutico se completó con 11 sesiones, la mayoría quincenales, y los resultados de la evaluación al terminar el tratamiento mostraron un descenso notable de los síntomas depresivos de la paciente (según el BDI-II) con respecto a la evaluación inicial. Asimismo, en la entrevista diagnóstica post-tratamiento no cumplía tampoco los criterios de depresión mayor. En cuanto a la pareja, ambos percibieron la relación como más armónica (según el DAS). Dentro de las limitaciones propias de los estudios de caso único, este trabajo permite ilustrar las potencialidades del enfoque sistémico en el tratamiento de la depresión.

Problems of the randomization test for AB designs

N = 1 designs imply repeated registrations of the behaviour of the same experimental unit and the measurements obtained are often few due to time limitations, while they are also likely to be sequentially dependent. The analytical techniques needed to enhance statistical and clinical decision making have to deal with these problems. Different procedures for analysing data from single-case AB designs are discussed, presenting their main features and revising the results reported by previous studies. Randomization tests represent one of the statistical methods that seemed to perform well in terms of controlling false alarm rates. In the experimental part of the study a new simulation approach is used to test the performance of randomization tests and the results suggest that the technique is not always robust against the violation of the independence assumption. Moreover, sensitivity proved to be generally unacceptably low for series lengths equal to 30 and 40. Considering the evidence available, there does not seem to be an optimal technique for single-case data analysis

Influence of heart motion on cardiac output estimation by means of electrical impedance tomography: a case study.

Electrical impedance tomography (EIT) is a non-invasive imaging technique that can measure cardiac-related intra-thoracic impedance changes. EIT-based cardiac output estimation relies on the assumption that the amplitude of the impedance change in the ventricular region is representative of stroke volume (SV). However, other factors such as heart motion can significantly affect this ventricular impedance change. In the present case study, a magnetic resonance imaging-based dynamic bio-impedance model fitting the morphology of a single male subject was built. Simulations were performed to evaluate the contribution of heart motion and its influence on EIT-based SV estimation. Myocardial deformation was found to be the main contributor to the ventricular impedance change (56%). However, motion-induced impedance changes showed a strong correlation (r = 0.978) with left ventricular volume. We explained this by the quasi-incompressibility of blood and myocardium. As a result, EIT achieved excellent accuracy in estimating a wide range of simulated SV values (error distribution of 0.57 ± 2.19 ml (1.02 ± 2.62%) and correlation of r = 0.996 after a two-point calibration was applied to convert impedance values to millilitres). As the model was based on one single subject, the strong correlation found between motion-induced changes and ventricular volume remains to be verified in larger datasets.

Comparing N = 1 effect size indices in presence of autocorrelation

Generalization from single-case designs can be achieved by means of replicating individual studies across different experimental units and settings. When replications are available, their findings can be summarized using effect size measurements and integrated through meta-analyses. Several procedures are available for quantifying the magnitude of treatment"s effect in N = 1 designs and some of them are studied in the current paper. Monte Carlo simulations were employed to generate different data patterns (trend, level change, slope change). The experimental conditions simulated were defined by the degrees of serial dependence and phases" length. Out of all the effect size indices studied, the Percent of nonoverlapping data and standardized mean difference proved to be less affected by autocorrelation and perform better for shorter data series. The regression-based procedures proposed specifically for single-case designs did not differentiate between data patterns as well as simpler indices.

Towards high-quality simultaneous EEG-fMRI at 7T: Detection and reduction of EEG artifacts due to head motion.

The enhanced functional sensitivity offered by ultra-high field imaging may significantly benefit simultaneous EEG-fMRI studies, but the concurrent increases in artifact contamination can strongly compromise EEG data quality. In the present study, we focus on EEG artifacts created by head motion in the static B0 field. A novel approach for motion artifact detection is proposed, based on a simple modification of a commercial EEG cap, in which four electrodes are non-permanently adapted to record only magnetic induction effects. Simultaneous EEG-fMRI data were acquired with this setup, at 7T, from healthy volunteers undergoing a reversing-checkerboard visual stimulation paradigm. Data analysis assisted by the motion sensors revealed that, after gradient artifact correction, EEG signal variance was largely dominated by pulse artifacts (81-93%), but contributions from spontaneous motion (4-13%) were still comparable to or even larger than those of actual neuronal activity (3-9%). Multiple approaches were tested to determine the most effective procedure for denoising EEG data incorporating motion sensor information. Optimal results were obtained by applying an initial pulse artifact correction step (AAS-based), followed by motion artifact correction (based on the motion sensors) and ICA denoising. On average, motion artifact correction (after AAS) yielded a 61% reduction in signal power and a 62% increase in VEP trial-by-trial consistency. Combined with ICA, these improvements rose to a 74% power reduction and an 86% increase in trial consistency. Overall, the improvements achieved were well appreciable at single-subject and single-trial levels, and set an encouraging quality mark for simultaneous EEG-fMRI at ultra-high field.

Biopsies de la prostate en 2015: quelle biopsie pour quel patient [Prostate biopsy: which strategy for which patient?].

L'adoption de l'IRM dans le parcours diagnostique a déterminé la transition des biopsies aléatoires aux biopsies ciblées vers les lésions visibles à l'imagerie. L'utilisation de logiciels rendant possible la fusion d'images IRM et échographiques permet d'améliorer significativement la précision diagnostique de ces biopsies. De plus, pour déterminer l'éligibilité d'un patient à une thérapie focale, davantage de précision diagnostique est requise au niveau de toute la glande ; par conséquent, des biopsies avec une densité d'échantillonnage plus élevée par voie transpérinéale peuvent être proposées.Les nouvelles techniques de biopsie de la prostate permettent une prise en charge personnalisée grâce à une meilleure caractérisation de l'agressivité et de l'extension locale du cancer de la prostate. The adoption of multiparametric MRI within the diagnostic pathway has allowed urologists to move from random biopsy to targeted biopsy directed towards MR-visible lesions. The use of software for MR to TRUS fusion may enhance the diagnostic accuracy of targeted biopsy. To determine the eligibility for tissue-preserving approaches, further precision is required, and template prostate mapping biopsy may be offered. The employment of novel biopsy techniques provide better characterisation of the disease, and allows a tailored approach to a single subject.

Estudi del condicionament d’una vivenda prefabricada amb criteris de sostenibilitat i d’autosuficiència

Partint del projecte bàsic d’un habitatge unifamiliar aïllat, projectat amb sistema prefabricat, onhi ha definida l’arquitectura i de forma molt bàsica el sistema estructural, els tancaments, lesinstal•lacions i els acabats, es pretén realitzar un estudi que es basi en la millora de l’envoltantespaial i de les instal•lacions per tal d’aconseguir un habitatge energèticament més eficientrespecte a la proposada inicialment.Concretament, es tracta d’un habitatge unifamiliar aïllat, del model tipus “CUBIC EVOLUTION”,dissenyat pels arquitectes Joaquin Torres i Rafael Llamazares de l’estudi d’arquitectura A-Cero.Aquest model, presenta una superfície de 290,91m2 útils i de 342,76m2 construïts, distribuïtsd’una manera molt raonable al seu ús.Per tant, l’objectiu principal d’aquest projecte final de grau, és projectar el condicionament del’envoltant, de totes les instal•lacions amb sistemes renovables i sostenibles necessàries en lavivenda i de diferents sistemes passius d’estalvi energètic de la vivenda prefabricada de l’estildescrit anteriorment, tenint presents criteris de sostenibilitat i autosuficiència, sense deixar debanda la condició estètica de la vivenda proposada en el projecte bàsic, de manera que aquestaes pugui autosubministrar la major part de l’energia i aigua que necessita, i complint sempre lanormativa actual.També es tindran en compte aspectes bioclimàtics, tals com ubicació, orientació, il•luminaciónatural, ventilació natural, pluja, etc., per tal d’adaptar-se a les condicions climàtiques i de l’entornon està situada i permetre a l’edifici estalviar la major quantitat d’energia possible

Using stimulus equivalence to teach monetary skills to school-age children with autism

The present study evaluated the use of stimulus equivalence in teaching monetary skills to school aged children with autism. An AB within-subject design with periodic probes was used. At pretest, three participants demonstrated relation DA, an auditory-visual relation (matching dictated coin values to printed coin prices). Using a three-choice match-to-sample procedure, with a multi-component intervention package, these participants were taught two trained relations, BA (matching coins to printed prices) and CA (matching coin combinations to printed prices). Two participants achieved positive tests of equivalence, and the third participant demonstrated emergent performances with a symmetric and transitive relation. In addition, two participants were able to show generalization of learned skills with a parent, in a second naturalistic setting. The present research replicates and extends the results of previous studies by demonstrating that stimulus equivalence can be used to teach an adaptive skill to children with autism.

Effectiveness of computer training on attentional skills

This paper presents two studies, both examining the efficacy of a computer programme (Captain's Log) in training attentional skills. The population of interest is the traumatically brain injured. Study #1 is a single-case design that offers recommendations for the second, .larger (N=5) inquiry. Study #2 is an eight-week hierarchical treatment programme with a multi-based testing component. Attention, memory, listening comprehension, locus-of-control, self-esteem, visuo-spatial, and general outcome measures are employed within the testing schedule. Results suggest that any improvement was a result of practice effects. With a few single-case exceptions, the participants showed little improvement in the dependent measures.

Electrophysiological constituents of the P100 and N170 ERP complex: De-constructing of face processing using independent component analysis and robust estimation.

The initial timing of face-specific effects in event-related potentials (ERPs) is a point of contention in face processing research. Although effects during the time of the N170 are robust in the literature, inconsistent effects during the time of the P100 challenge the interpretation of the N170 as being the initial face-specific ERP effect. The interpretation of the early P100 effects are often attributed to low-level differences between face stimuli and a host of other image categories. Research using sophisticated controls for low-level stimulus characteristics (Rousselet, Husk, Bennett, & Sekuler, 2008) report robust face effects starting at around 130 ms following stimulus onset. The present study examines the independent components (ICs) of the P100 and N170 complex in the context of a minimally controlled low-level stimulus set and a clear P100 effect for faces versus houses at the scalp. Results indicate that four ICs account for the ERPs to faces and houses in the first 200ms following stimulus onset. The IC that accounts for the majority of the scalp N170 (icNla) begins dissociating stimulus conditions at approximately 130 ms, closely replicating the scalp results of Rousselet et al. (2008). The scalp effects at the time of the P100 are accounted for by two constituent ICs (icP1a and icP1b). The IC that projects the greatest voltage at the scalp during the P100 (icP1a) shows a face-minus-house effect over the period of the P100 that is less robust than the N 170 effect of icN 1 a when measured as the average of single subject differential activation robustness. The second constituent process of the P100 (icP1b), although projecting a smaller voltage to the scalp than icP1a, shows a more robust effect for the face-minus-house contrast starting prior to 100 ms following stimulus onset. Further, the effect expressed by icP1 b takes the form of a larger negative projection to medial occipital sites for houses over faces partially canceling the larger projection of icP1a, thereby enhancing the face positivity at this time. These findings have three main implications for ERP research on face processing: First, the ICs that constitute the face-minus-house P100 effect are independent from the ICs that constitute the N170 effect. This suggests that the P100 effect and the N170 effect are anatomically independent. Second, the timing of the N170 effect can be recovered from scalp ERPs that have spatio-temporally overlapping effects possibly associated with low-level stimulus characteristics. This unmixing of the EEG signals may reduce the need for highly constrained stimulus sets, a characteristic that is not always desirable for a topic that is highly coupled to ecological validity. Third, by unmixing the constituent processes of the EEG signals new analysis strategies are made available. In particular the exploration of the relationship between cortical processes over the period of the P100 and N170 ERP complex (and beyond) may provide previously unaccessible answers to questions such as: Is the face effect a special relationship between low-level and high-level processes along the visual stream?

Cognitive Behavior Therapy for Obsessive-Compulsive Behavior in Children with Autism Spectrum Disorder: A Comparison of Hierarchical Linear Modelling and Visual Analysis

Behavioral researchers commonly use single subject designs to evaluate the effects of a given treatment. Several different methods of data analysis are used, each with their own set of methodological strengths and limitations. Visual inspection is commonly used as a method of analyzing data which assesses the variability, level, and trend both within and between conditions (Cooper, Heron, & Heward, 2007). In an attempt to quantify treatment outcomes, researchers developed two methods for analysing data called Percentage of Non-overlapping Data Points (PND) and Percentage of Data Points Exceeding the Median (PEM). The purpose of the present study is to compare and contrast the use of Hierarchical Linear Modelling (HLM), PND and PEM in single subject research. The present study used 39 behaviours, across 17 participants to compare treatment outcomes of a group cognitive behavioural therapy program, using PND, PEM, and HLM on three response classes of Obsessive Compulsive Behaviour in children with Autism Spectrum Disorder. Findings suggest that PEM and HLM complement each other and both add invaluable information to the overall treatment results. Future research should consider using both PEM and HLM when analysing single subject designs, specifically grouped data with variability.

Blocking Top-down awareness of Kanizsa Figures: An ERP Investigation into Bottom-up Processing of Illusory Contours

Neural models of the processing of illusory contour (ICs) diverge from one another in terms of their emphasis on bottom-up versus top-down constituents. The current study uses a dichoptic fusion paradigm to block top-down awareness of ICs in order to examine possible bottom-up effects. Group results indicate that the N170 ERP component is particularly sensitive to ICs at central occipital sites when top-down awareness of the stimulus is permitted. Furthermore, single-subject statistics reveal that the IC N170 ERP effect is highly variable across individuals in terms of timing and topographical spread. The results suggest that the ubiquitous N170 effect to ICs found in the literature depends, at least in part, on participants’ awareness of the stimulus. Therefore a strong bottom-up model of IC processing at the time of the N170 is unlikely.

Évaluation de l’efficacité d’un programme d’entraînement parental pour les parents d’enfants souffrant d’anxiété de séparation

Le trouble d’anxiété de séparation (TAS) est le trouble anxieux le plus prévalent chez les enfants. Il apparaît tôt et entraîne plusieurs conséquences négatives. La thérapie cognitivo-comportementale (TCC) a été reconnue efficace pour traiter les troubles anxieux. Toutefois, peu d’études ont vérifié son efficacité pour le traitement spécifique du TAS et très peu en ont examiné l’effet auprès d’enfants de moins de 7 ans. Les quelques interventions étudiées visant les moins de 7 ans ont en commun d’inclure le parent dans le traitement ou de l’offrir directement à celui-ci. L’objectif principal de cette thèse est de vérifier l’efficacité d’un programme d’entraînement parental de type TCC, adapté pour les parents d’enfants de 4 à 7 ans souffrant de TAS. Cette étude vise également deux objectifs spécifiques : observer la fluctuation des symptômes de TAS de l’enfant pendant le traitement et examiner l’impact du programme sur les variables parentales. Un devis à cas unique à niveaux de base multiples a été utilisé. Six familles ont pris part à l’étude. Des entrevues semi-structurées, des questionnaires auto-administrés et des calepins d’auto-observations quotidiennes ont été utilisés auprès des parents pour mesurer les symptômes anxieux des enfants, leurs pratiques parentales, le stress parental et leurs symptômes anxieux et dépressifs. Des questionnaires sur les difficultés de l’enfant incluant l’anxiété ont aussi été envoyés à l’éducatrice ou à l’enseignante. Tous les questionnaires ont été administrés aux trois temps de mesure (prétraitement, post-traitement et relance 3 mois). Les calepins d’auto-observations ont été remplis quotidiennement durant le niveau de base, pour toute la durée de l’intervention et pendant une à deux semaines à la relance. Les résultats de l’étude indiquent que cinq enfants sur six ne répondent plus au diagnostic de TAS suite au traitement ainsi que trois mois plus tard. Les résultats des calepins d’auto-observations montrent une amélioration claire des manifestations principales de TAS pour la moitié des enfants et plus mitigée pour l’autre moitié, de même qu’une amélioration systématique de la fréquence hebdomadaire totale de manifestations de TAS suite à l’intervention pour quatre enfants. Les résultats aux questionnaires remplis par les parents montrent une amélioration des symptômes d’anxiété et de TAS chez quatre enfants au post-test et/ou à la relance, tandis que les questionnaires de l’éducatrice (ou enseignante) suggèrent que les symptômes anxieux des enfants se manifestaient peu dans leur milieu scolaire ou de garde. L’impact du programme sur le stress parental et les pratiques parentales est également mitigé. Ces résultats suggèrent que le Programme d’entraînement parental pour les enfants souffrant d’anxiété de séparation (PEP-AS) est efficace pour réduire les symptômes de TAS chez les enfants d’âge préscolaire ou en début de parcours scolaire et appuient la pertinence d’offrir le traitement aux parents et d’inclure un volet relationnel. D’autres études seront cependant nécessaires pour répliquer ces résultats auprès d’un plus vaste échantillon. Il serait également intéressant de vérifier les effets indépendants des différentes composantes du traitement et d’évaluer les effets du programme sur davantage de pratiques parentales associées spécifiquement à l’anxiété.