Psicothema was founded in Asturias (northern Spain) in 1989, and is published jointly by the Psychology Faculty of the University of Oviedo and the Psychological Association of the Principality of Asturias (Colegio Oficial de Psicología del Principado de Asturias).
We currently publish four issues per year, which accounts for some 100 articles annually. We admit work from both the basic and applied research fields, and from all areas of Psychology, all manuscripts being anonymously reviewed prior to publication.
Héctor González-Pardo, Jorge L. Arias, Guillermo Vallejo, and Nélida M. Conejo
Universidad de Oviedo
Background: Exposure to maternal separation (MS) in rodents may have long-lasting consequences for the structure and function of several brain regions, eventually associated with alterations in cognition and emotion later in life. Post-weaning environmental enrichment (EE) has been reported to ameliorate the detrimental effects of exposure to early life stress mainly in the hippocampus. Method: In vivo magnetic resonance imaging (MRI) was applied to evaluate possible volumetric changes in the dorsal and ventral hippocampus, the medial prefrontal cortex and the dorsal striatum of 90-day-old male rats after daily MS for 240 min from postnatal days 2-21. Results: No significant volume changes were found in the selected brain regions in MS animals as compared with an age-matched control group. However, additional groups of control and MS animals with EE from days 21-60 showed significant volume increases in the medial prefrontal cortex and the ventral hippocampus as compared to the groups without EE. In addition, general hemispheric asymmetry was found in the volume of the brain regions measured. Conclusions: Our results demonstrate that EE could have differential effects depending on previous exposure to MS and on the development of brain lateralization.
Influencia del enriquecimiento ambiental en el volumen de regiones cerebrales sensibles a estrés vital temprano por separación materna en ratas. Antecedentes: la exposición a separación materna (MS) en roedores puede tener consecuencias a largo plazo en la estructura y función de regiones cerebrales, particularmente asociadas con alteraciones cognitivas y emocionales. El enriquecimiento ambiental (EE) tras la lactancia ha mostrado contrarrestar los efectos adversos de la exposición a estrés temprano principalmente en el hipocampo. Método: se obtuvieron imágenes por resonancia magnética (IRM) in vivo para evaluar los posibles cambios volumétricos en el hipocampo dorsal y ventral, la corteza prefrontal medial y el estriado dorsal en ratas macho de 90 días de edad tras MS durante 240 min diarios entre los días 2 y 21. Resultados: no hallamos cambios significativos de volumen en las regiones cerebrales seleccionadas de animales MS, frente a un grupo control. Sin embargo, grupos adicionales de animales control y MS con EE entre los días 21-60 mostraron incrementos volumétricos significativos en la corteza prefrontal medial y el hipocampo ventral, frente a grupos sin EE. Asimismo, se encontró asimetría hemisférica en el volumen de las regiones cerebrales medidas. Conclusiones: nuestros resultados demuestran que el EE tendría efectos diferenciales dependiendo de la exposición previa a la MS y en el desarrollo de la lateralización cerebral.