Sistemas neurales de relevancia en el contexto de la psicobiología de la ansiedad: una revisión

Resumen

La ansiedad es un estado emocional central de características muy complejas que, al menos en términos de respuesta, se asemeja en gran medida al miedo. En las ültimas décadas, estudios neurobiológicos y psicobiológicos han identificado numerosas estructuras y circuitos cerebrales estrechamente relacionados con este tipo de respuestas, así como con el estado central característico. Destacan, por su especial relevancia, el sistema límbico (incluyendo el sistema septohipocampal, la amígdala y el hipotálamo posterior) y los sistemas monoaminérgicos ascendentes (principalmente de serotonina y norepinefrina), lugares donde, además, las sustancias ansiolíticas podrían ejercer su efecto terapéutico. El principal objetivo del presente trabajo es revisar la precisa implicación de estos sistemas neurales en la modulación de ese estado emocional definido como ansiedad.     

La falacia de la validación personal: Más efectos placebo

RESUMEN

En este artículo se pone a prueba la influencia de efectos placebo en la aceptación de informes evaluativos y diagnósticos por los sujetos. Tras introducir brevemente el tema y plantear las hipótesis, los autores describen el método y los resultados de su investigación. En la discusión explican que estos resultados sugieren que la aceptación del diagnóstico que ofrece un profesional es un fenómeno general independiente de las características personales de los individuos que lo reciben, poniendo en entredicho el fenómeno de la validación personal y, al mismo tiempo, interactúa con determinadas características profesionales de los sujetos, ligadas a imágenes de personalidad a las que son más propensos. Los autores también analizan una limitación importante de su trabajo, el tamaño reducido de la muestra, y finalizan destacando que es el contenido del informe, más que el tipo de pruebas o profesionales, lo que parece afectar diferencialmente a distintos grupos profesionales.     

Assessing Approximate Fit in Categorical Data Analysis

A family of Root Mean Square Error of Approximation (RMSEA) statistics is proposed for assessing the goodness of approximation in discrete multivariate analysis with applications to item response theory (IRT) models. The family includes RMSEAs to assess the approximation up to any level of association of the discrete variables. Two members of this family are RMSEA₂, which uses up to bivariate moments, and the full information RMSEA_n. The RMSEA₂ is estimated using the M₂ statistic of Maydeu-Olivares and Joe (2005, 2006), whereas for maximum likelihood estimation, RMSEA_n is estimated using Pearson's X² statistic. Using IRT models, we provide cutoff criteria of adequate, good, and excellent fit using the RMSEA₂. When the data are ordinal, we find a strong linear relationship between the RMSEA₂ and the Standardized Root Mean Squared Residual goodness-of-fit index. We are unable to offer cutoff criteria for the RMSEA_n as its population values decrease as the number of variables and categories increase.     

How Should We Assess the Fit of Rasch-Type Models? Approximating the Power of Goodness-of-Fit Statistics in Categorical Data Analysis

We investigate the performance of three statistics, R ₁, R ₂ (Glas in Psychometrika 53:525–546, 1988), and M ₂ (Maydeu-Olivares & Joe in J. Am. Stat. Assoc. 100:1009–1020, 2005, Psychometrika 71:713–732, 2006) to assess the overall fit of a one-parameter logistic model (1PL) estimated by (marginal) maximum likelihood (ML). R ₁ and R ₂ were specifically designed to target specific assumptions of Rasch models, whereas M ₂ is a general purpose test statistic. We report asymptotic power rates under some interesting violations of model assumptions (different item discrimination, presence of guessing, and multidimensionality) as well as empirical rejection rates for correctly specified models and some misspecified models. All three statistics were found to be more powerful than Pearson’s X ² against two- and three-parameter logistic alternatives (2PL and 3PL), and against multidimensional 1PL models. The results suggest that there is no clear advantage in using goodness-of-fit statistics specifically designed for Rasch-type models to test these models when marginal ML estimation is used.     

Facilitation and interference of behavioral responses by task-irrelevant affect-laden stimuli

Emotional interference on behavior is commonly observed when task-irrelevant negative stimuli appear before behavioral targets. One explanation postulates that affect-laden stimuli readily capture attention, interfering with the processing of the upcoming target. Emotional stimuli might also preactivate motor programs incompatible with the demanded response. Using a cued go/no-go procedure we showed that task-irrelevant unpleasant stimuli cause interference or facilitation depending on their onset asynchrony relative to the target. We observed interference with short (200 ms) stimulus-target asynchronies and facilitation for longer ones (600 ms), both for key press (Experiment 1) and key release (Experiment 2) responses. The interference effect is compatible with an attentional explanation, but the behavioral facilitation is hard to accommodate within either attentional or motor accounts. This interference-facilitation pattern can be explained assuming that once the attentional effect subsides, emotional processing may enhance the perceptual processing of the stimuli, or lower the decision threshold, thereby facilitating the response selection process.     

Religious upbringing and current religiosity in Spanish nursing and medicine students

The influence of religious education in the family upon current spiritual and religious tendencies was assessed in a sample of 599 Spanish nurse and medicine students using a religiosity scale and answers to a series of belief/disbelief statements. Results showed that nursing and medicine students were equally low-religious, with no differences in religiosity total scores between participants coming from religious families; however, medical students coming from nonreligious families showed higher religiousness than the corresponding nursing trainees. This distinction appeared both across religiosity items and in a variety of responses to belief/disbelief of Christian/secular assertions. Regression analysis showed that religious family background was a consistent predictor of religious beliefs at young adulthood, and its influence was higher for medical students. In addition to establish religious upbringing as an important factor modulating enduring religiosity, these findings provide distinctions between nurse and medical trainees, and reproduce, in a Spanish mainly catholic sample, the structure of religiosity factors previously found on North American mainline protestants.     

Trajectories of Experience of Real Life Events. A Semiotic Approach to the Dynamics of Positioning

This paper is devoted to the study of experience as a semiotic process of constructing the personal meaning of the situation lived. Its main purpose is to devise a semiotic methodology capable of describing and explaining the dynamics of positioning when facing personal lived experiences in real life contexts. Twenty four young adults were exposed to a simulated conflict and then asked to write a narrative of their understanding of the incident and a self-report of their personal experiences. Results show how narratives and trajectories of experience present different forms in each participant, which could be related to: a) the understanding of the situation lived and the position taken regarding the conflict; and b) the position each participant takes regarding the reports they had to produce for the researchers. The incorporation of reflexivity into the applied method allows identification of how the dynamics of double positioning leave traces in the records produced.     

Reflections on trauma,symbolization and psychic pain in a case of neurosis and a case of psychosis

This paper seeks to advance some considerations on trauma, historical reality, its symbolization and the psychic pain generated by the investigation of unconscious processes in psychoanalytic treatment. These themes will be explored by demonstrating the differences arising between traumatic experiences and their expression in phantasy, as they occurred in a case of neurosis and another of psychosis. In each case, the differences in the features of the symbolization and the processes of working through shall also be taken into consideration. Particular attention shall be paid to the specific difficulties encountered by the analyst in the interpretative treatment of the trauma resulting from the amount of psychic pain induced in the patient, which at times proves to be an insurmountable barrier and a destructive distortion of the process.