Stress effects on cognitive function in healthy adults

In our lives, we are constantly exposed to different sources of stress, specifically psychological or social. Our reaction to stress is an adaptive response due to its role in facilitating survival. However, stress can also have immediate and delayed damaging consequences for health, and it is considered one of the most significant health problems of the 21st century, according to the World Health Organization (2001). The impact of stress extends to most of the physiological systems (i.e. cardiovascular, digestive, immune, neuroendocrine or nervous), resulting in numerous diseases. Cognitive problems stand out among the stress effects related to the nervous system. Given the large impact that these problems can have on society in general, and on individuals in particular, the need to understand more about this link is clear. This is one of the reasons for the growing interest in investigating the main mechanisms underlying the stress impact on different cognitive processes, such as memory, attention or executive functions. Several factors related to the characteristics of the stressor, the individual and the cognitive process assessed seem to play an important role in determining the direction of these stress effects. Thus, this thesis focuses on the way stress affects cognition, specifically memory performance, in healthy adults, analyzing the role of some of these factors. The first section of the first chapter discusses the evolution of the stress concept and explains what the stress response is. In the second part, the link between stress and memory is explained, detailing which brain structures are related to the control of the stress response and the cognitive processes. Then, a brief summary of the studies about the effect of acute stress on memory performance is presented. Moreover, the Hypothalamus-Pituitary-Adrenal axis (HPA-axis) in basal conditions (non-stress) is addressed, again summarizing the studies that have investigated the relationship between HPA-axis functioning and cognitive performance. Finally, the chapter ends with the main goals and hypothesis of this thesis and a general description of the material and methods used in the empirical chapters. In the second chapter, the first study is presented. In this study, we examined the effects of stress-prior learning on two types of memory (i.e. non-declarative and declarative memory) in young adults. Here, the material to be remembered is neutral, and the role of sex is considered. Next, in the third chapter of the thesis, following a similar design, the second study carries out a direct comparison of older and young adults. The fourth chapter describes the third study, which investigates the stress effects on memory retrieval. Now, the stressor is applied before the retrieval tasks, and the material to be remembered is neutral and emotional. Again, older and young adults of both sexes are compared. In the last study, the fifth chapter analyzes the relationships between the cortisol awakening response (CAR) and the diurnal cortisol slope (DCS), two different components of the diurnal cortisol cycle, and different memory tasks. The sixth chapter contains a general discussion and the main findings of the aforementioned studies; the strengths and limitations of this thesis and the direction of the next steps in the research on this topic are discussed here. Finally, the seventh chapter presents the main conclusions of the studies included in this thesis

Intervenciones terapéuticas para el tratamiento del síndrome de burnout: una revisión sistemática.

Introducción: El síndrome de burnout es un problema frecuente en la actualidad que está provocado por una respuesta emocional e interpersonal crónica ante los estresores en el trabajo. Objetivos: Establecer una propuesta de intervención terapéutica lo más eficaz posible para el tratamiento del burnout. Métodos: Se ha realizado una revisión sistemática siguiendo las directrices PRISMA con estudios encontrados en las bases de datos Pubmed, Scopus y BASE. Se seleccionaron artículos en inglés o español, publicados en revistas científicas entre 2004 y 2019, con un diseño experimental o cuasi experimental y con participantes mayores de 18 años. Se llevó a cabo un cribado desde los 206 artículos de la búsqueda inicial hasta los 22 analizados, extrayendo sus características principales para su comparación. Resultados: Los efectos de la intervención sobre el burnout son diferentes dependiendo de la corriente terapéutica o técnica psicoterapéutica aplicada. Conclusiones: La combinación de terapia cognitivo conductual y terapias de tercera generación son las intervenciones utilizadas en el síndrome de burnout que cuentan con mejores resultados, aunque habría que continuar investigando en el futuro. Palabras clave: Intervención en síndrome de burnout, tratamiento de burnout, estrés laboral.<br /

La influencia del estrés en el rendimiento cognitivo

La prevalencia del estrés ha generado un mayor interés por conocer sus efectos en elrendimiento cognitivo. El objetivo de este estudio es analizar la respuesta psicológica y lainfluencia tanto en el rendimiento de la memoria como académico ante un estresorpsicosocial. Para ello, 33 estudiantes de entre 18 y 21 años fueron expuestos dos sesiones,una control y otra estresante (examen oficial del grado de Psicología). En ambas se evaluó larespuesta psicológica, el efecto del estresor sobre la recuperación del material emocional yneutro, así como la relación entre la respuesta psicológica con el rendimiento mnésico yacadémico. Como se esperaba, los resultados mostraron mayores niveles ansiedad y afectonegativo en presencia del estresor. En cuanto al rendimiento en la memoria, el estresorperjudicó el recuerdo libre. Además, en general los participantes recordaban con mayorfacilidad el material emocional. También se observaron relaciones negativas entre larespuesta psicológica al estresor y las tareas de rendimiento en la memoria, aunque estasvariables no se asociaron significativamente con el rendimiento académico. Estos hallazgosindican que, como se ha visto con estresores agudos de laboratorio, un estresor ecológicocomo un examen oficial, afecta de la misma manera en el deterioro de la fase de recuperaciónde la memoria.<br /

Sobrecarga y variables de impacto negativo en cuidadores de pacientes con cáncer avanzado: una revisión sistemática

Introducción. El cáncer se ha convertido en una de las principales causas de muerte, principalmente en el mundo desarrollado. En numerosas ocasiones, se convierte en enfermedad de larga duración, que sobretodo en un estadio avanzado, requiere la figura del cuidador, sometido a numerosas consecuencias negativas derivadas de este cuidado: la sobrecarga. Objetivo. Explorar las variables y consecuencias negativas de la sobrecarga de los cuidadores de pacientes con cáncer avanzado, independientemente del lugar de procedencia del individuo, y del tipo de cáncer padecido. Método. Se ha llevado a cabo una revisión sistemática de estudios que cumplían los criterios de inclusión establecidos, en las bases de datos de Pubmed y Web of Sciencie, incluyéndose finalmente un total de 16 artículos. Resultados y discusión. Los resultados aportan numerosas variables negativas que afectan e incrementan la sobrecarga del cuidador. En numerosos casos, esta sobrecarga genera más consecuencias negativas, produciéndose así una retroalimentación, que si no se detiene tendrá efectos fatales en la propia salud del cuidador.<br /

A low cortisol response to acute stress is related to worse basal memory performance in older people

Age-related memory decline has been associated with a faulty regulation of the hypothalamus-pituitary-adrenal axis (HPA-axis). The aim of this study was to investigate whether the magnitude of the stress-induced cortisol increase is related to memory performance when memory is measured in non-stressful conditions. To do so, declarative and working memory performance were measured in 31 men and 35 women between 55 and 77 years of age. On a different day, the magnitude of their cortisol response to acute psychosocial stress was measured. The relationship between the cortisol response and memory performance was U shaped: a low cortisol response to stress was related to poorer declarative and working memory performance, whereas those who did not increase their cortisol levels and those who had the largest cortisol increase had better declarative and working memory capabilities. Sex did not moderate these relationships. These results suggest that a low cortisol response to stress could reflect a defective HPA-axis response to stressors that is accompanied by poorer memory performance. Conversely, a high cortisol response seems to reflect a correct functioning of the HPA-axis and may protect against memory deficits in the later stages of human life

Intergroup conflict and rational decision making

The literature has been relatively silent about post-conflict processes. However, understanding the way humans deal with post-conflict situations is a challenge in our societies. With this in mind, we focus the present study on the rationality of cooperative decision making after an intergroup conflict, i.e., the extent to which groups take advantage of post-conflict situations to obtain benefits from collaborating with the other group involved in the conflict. Based on dual-process theories of thinking and affect heuristic, we propose that intergroup conflict hinders the rationality of cooperative decision making. We also hypothesize that this rationality improves when groups are involved in an in-group deliberative discussion. Results of a laboratory experiment support the idea that intergroup conflict ¿associated with indicators of the activation of negative feelings (negative affect state and heart rate)¿ has a negative effect on the aforementioned rationality over time and on both group and individual decision making. Although intergroup conflict leads to sub-optimal decision making, rationality improves when groups and individuals subjected to intergroup conflict make decisions after an in-group deliberative discussion. Additionally, the increased rationality of the group decision making after the deliberative discussion is transferred to subsequent individual decision making

Albiglutide and cardiovascular outcomes in patients with type 2 diabetes and cardiovascular disease (Harmony Outcomes): a double-blind, randomised placebo-controlled trial

Background: Glucagon-like peptide 1 receptor agonists differ in chemical structure, duration of action, and in their effects on clinical outcomes. The cardiovascular effects of once-weekly albiglutide in type 2 diabetes are unknown. We aimed to determine the safety and efficacy of albiglutide in preventing cardiovascular death, myocardial infarction, or stroke. Methods: We did a double-blind, randomised, placebo-controlled trial in 610 sites across 28 countries. We randomly assigned patients aged 40 years and older with type 2 diabetes and cardiovascular disease (at a 1:1 ratio) to groups that either received a subcutaneous injection of albiglutide (30–50 mg, based on glycaemic response and tolerability) or of a matched volume of placebo once a week, in addition to their standard care. Investigators used an interactive voice or web response system to obtain treatment assignment, and patients and all study investigators were masked to their treatment allocation. We hypothesised that albiglutide would be non-inferior to placebo for the primary outcome of the first occurrence of cardiovascular death, myocardial infarction, or stroke, which was assessed in the intention-to-treat population. If non-inferiority was confirmed by an upper limit of the 95% CI for a hazard ratio of less than 1·30, closed testing for superiority was prespecified. This study is registered with ClinicalTrials.gov, number NCT02465515. Findings: Patients were screened between July 1, 2015, and Nov 24, 2016. 10 793 patients were screened and 9463 participants were enrolled and randomly assigned to groups: 4731 patients were assigned to receive albiglutide and 4732 patients to receive placebo. On Nov 8, 2017, it was determined that 611 primary endpoints and a median follow-up of at least 1·5 years had accrued, and participants returned for a final visit and discontinuation from study treatment; the last patient visit was on March 12, 2018. These 9463 patients, the intention-to-treat population, were evaluated for a median duration of 1·6 years and were assessed for the primary outcome. The primary composite outcome occurred in 338 (7%) of 4731 patients at an incidence rate of 4·6 events per 100 person-years in the albiglutide group and in 428 (9%) of 4732 patients at an incidence rate of 5·9 events per 100 person-years in the placebo group (hazard ratio 0·78, 95% CI 0·68–0·90), which indicated that albiglutide was superior to placebo (p&lt;0·0001 for non-inferiority; p=0·0006 for superiority). The incidence of acute pancreatitis (ten patients in the albiglutide group and seven patients in the placebo group), pancreatic cancer (six patients in the albiglutide group and five patients in the placebo group), medullary thyroid carcinoma (zero patients in both groups), and other serious adverse events did not differ between the two groups. There were three (&lt;1%) deaths in the placebo group that were assessed by investigators, who were masked to study drug assignment, to be treatment-related and two (&lt;1%) deaths in the albiglutide group. Interpretation: In patients with type 2 diabetes and cardiovascular disease, albiglutide was superior to placebo with respect to major adverse cardiovascular events. Evidence-based glucagon-like peptide 1 receptor agonists should therefore be considered as part of a comprehensive strategy to reduce the risk of cardiovascular events in patients with type 2 diabetes. Funding: GlaxoSmithKline

Psicothema

Resumen tomado de la publicaciónRespuesta psicofisiológica a estresores sociales: relevancia del sexo y la edad. Antecedentes: entender los factores involucrados en la respuesta psicofisiológica ante situaciones de estrés agudo es crucial para prevenir y tratar problemas de salud relacionados con el estrés. El objetivo es integrar los resultados de estudios en humanos relacionados con el papel del sexo y la edad en las diferencias individuales en la respuesta de estrés en diferentes biomarcadores. Metodología: se integran los principales resultados de nuestro grupo de investigación y de otros laboratorios centrados en las diferencias debidas al sexo y la edad en la respuesta psicofisiológica a situaciones de estrés psicosocial. Resultados: se observan diferencias en la respuesta de estrés entre hombres y mujeres en presión sanguínea y en niveles de cortisol, pero no en frecuencia cardíaca, variabilidad de la frecuencia cardíaca y alfa-amilasa. Además, la edad influye en los niveles de cortisol y en la actividad basal del sistema nervioso simpático. Conclusiones: los resultados ponen de manifiesto la importancia de tener en cuenta el sexo y la edad de los participantes para poder entender la respuesta de estrés y sus posibles efectos en salud.Universidad de Oviedo. Biblioteca de Psicología; Plaza Feijoo, s/n.; 33003 Oviedo; Tel. +34985104146; Fax +34985104126; [email protected]

Primer reporte de Leporacarus gibbus (Acarina: Lestrophoridae) en conejos de carne (Oryctolagus cuniculus) en Costa Rica

Leporacarus gibbus virus es un ácaro de pelo de conejo que no penetra la piel, se ha descrito como patógeno incluso en elevadas infestaciones. El ciclo de vida es poco conocido y todos los estadios (huevo, larva, ninfa) se desarrollan sobre el conejo. Se alimenta de secreciones sebáceas y escamas epiteliales. La presencia del ácaro puede no estar asociada con la enfermedad y puede ser considerada como un ectoparásito comensal. Existe poca información sobre su prevalencia en casos de dermatitis o sobre su carácter zoonótico. Sin embargo, casos de dermatosis en humanos ha sido asociados por el contacto directo con conejos L. gibbus . El ácaro produce fuertemente alopecia, dermatitis húmeda y prurito; también puede provocar reacciones de hipersensibilidad. En conejos de vida libre se ha observado adelgazamiento de pelo en elevadas infestaciones, La presencia de puntos oscuros de tamaño diminuto en el pelaje puede ser el único signo. Dicho ácaro tiende a poblar el tercio distal del eje del pelo del área parasitada afectando principalmente dorso, ingle, flancos y abdomen ventral.Leporacarus gibbus virus is a rabbit hair mite that does not penetrate the skin, it has been described as pathogenic even in high infestations. The life cycle is poorly understood and all stages (egg, larva, nymph) develop on the rabbit. It feeds on sebaceous secretions and epithelial scales. The presence of the mite may not be associated with the disease and it can be considered as a commensal ectoparasite. There is little information on its prevalence in cases of dermatitis or on its zoonotic character. However, cases of dermatosis in humans have been associated with direct contact with L. gibbus rabbits. The mite strongly produces alopecia, moist dermatitis and pruritus; it can also cause hypersensitivity reactions. In free-living rabbits, hair thinning has been observed in high infestations. The presence of tiny dark spots on the fur may be the only sign. The mite tends to populate the distal third of the hair shaft of the parasitized area, mainly affecting the dorsum, groin, flanks and ventral abdomen.Universidad Nacional, Costa RicaEscuela de Medicina Veterinari

Psicothema

Resumen basado en el de la publicaciónDepresión y riesgo de suicidio en el deterioro cognitivo leve: el rol de los biomarcadores de la enfermedad de Alzheimer. Antecedentes: los pacientes con depresión y deterioro cognitivo leve (DCL) tienen un alto riesgo de desarrollar demencia. La depresión implica un alto riesgo de ideación suicida (IS) e intentos de suicidio (AS). Los biomarcadores de la enfermedad de Alzheimer (EA) pueden clarificar el papel de la depresión e IS en la EA. Método: cincuenta y nueve participantes >50 años con criterios de DCL-EA positivo (DCL-EA; 22) y negativo (DCL-NoEA; 24) y 13 controles sanos. La depresión fue evaluada con la Escala Geriátrica de Depresión (GDS-30) y la IS con el factor GDS-IS. Además, se midieron los siguientes biomarcadores en el líquido cefalorraquídeo: ß-amiloide (ß-A), tau hiperfosforilada (H-tau) y total (T-tau). Resultados: no se encontraron diferencias significativas entre los tres grupos de participantes en depresión o en IS. Sin embargo, en el grupo DCL-EA, niveles más bajos de H-tau y T-tau, indicadores de menor patología EA, se relacionaron significativamente con mayor riesgo de suicidio indirecto. Conclusiones: este resultado subraya la importancia de considerar la IS en fases iniciales de EA, y el potencial papel de los biomarcadores de EA para detectar sus síntomas.ES