Novel flavors elicit a cautious neophobic response which is attenuated as the flavor becomes familiar and safe. The attenuation of neophobia reveals the formation of a safe memory. Previous lesion ...studies in rats have reported that basolateral amygdala integrity is required for taste neophobia, but not neophobia to flavor, i.e., taste linked to an odorous component. Accordingly, immunohistochemical analyses show that novel tastes induced higher basolateral amygdala activity when compared to familiar ones. However, a different role of basolateral amygdala in flavor attenuation of neophobia is suggested by lesion studies using a vinegar solution. Studies assessing basolateral amygdala activity during flavor attenuation of neophobia are lacking. Thus, we quantified cytochrome oxidase as an index of basolateral amygdala activity along the first and second vinegar exposures in order to assess flavor neophobia and attenuation of neophobia.
We exposed adult male Wistar rats either once or twice to a 3% cider vinegar solution or water, and compared the basolateral amygdala, piriform cortex and caudate putamen brain metabolic activity using cytochrome c-oxidase histochemistry.
We found increased flavor intake and cytochrome c-oxidase histochemistry activity during the second exposure in basolateral amygdala, but not in the piriform cortex and caudate/putamen.
The main finding of the study is that BLA metabolic activity was higher in the group exposed to a familiar vinegar solution than in the groups exposed to either water or a novel vinegar solution.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
BACKGROUNDAdolescence in mammals is a period marked by increased novelty-seeking and enhanced responsiveness to the stressful properties of novel stimuli. Despite the need to taste potentially toxic ...novel foods during the adolescent growth spurt, there has been little study of taste neophobia and its attenuation.METHODFour experiments were carried out to compare taste neophobia and related memory processes in male and female adolescent (PND28) and adult (PND70) Wistar rats. Experiments 1 and 2 evaluated attenuation of taste neophobia to cider vinegar (3%) and sodium saccharin (0.1%) solutions were evaluated. Additionally, to test the role of memory in neophobia during adolescence, latent inhibition of taste aversion and object recognition memory were assessed in Experiment 3 and Experiment 4, respectively.RESULTSAdolescent and adult rats exhibited taste neophobia to the saccharin solution but adolescent rats required more exposure trials than adults to recognize the vinegar solution as safe. Both groups exhibited similar latent inhibition of taste aversion and object recognition memory. No sex effect was significant.CONCLUSIONSContrary to the accepted view associating adolescence with reduced neophobia, adolescent rats exhibited taste neophobia which even increased when sour tastes were encountered.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Background: Adolescence in mammals is a period marked by increased novelty-seeking and enhanced responsiveness to the stressful properties of novel stimuli. Despite the need to taste potentially ...toxic novel foods during the adolescent growth spurt, there has been little study of taste neophobia and its attenuation. Method: Four experiments were carried out to compare taste neophobia and related memory processes in male and female adolescent (PND28) and adult (PND70) Wistar rats. Experiments 1 and 2 evaluated attenuation of taste neophobia to cider vinegar (3%) and sodium saccharin (0.1%) solutions were evaluated. Additionally, to test the role of memory in neophobia during adolescence, latent inhibition of taste aversion and object recognition memory were assessed in Experiment 3 and Experiment 4, respectively. Results: Adolescent and adult rats exhibited taste neophobia to the saccharin solution but adolescent rats required more exposure trials than adults to recognize the vinegar solution as safe. Both groups exhibited similar latent inhibition of taste aversion and object recognition memory. No sex effect was significant. Conclusions: Contrary to the accepted view associating adolescence with reduced neophobia, adolescent rats exhibited taste neophobia which even increased when sour tastes were encountered. Keywords: Adolescence Attenuation of neophobia Flavor Recognition memory Rat Antecedentes: La adolescencia esta marcada por busqueda de la novedad y acentuada sensibilidad a las propiedades estresantes de los estimulos novedosos. A pesar de la necesidad de probar nuevos alimentos potencialmente toxicos durante el periodo de crecimiento adolescente, la neofobia gustativa y su atenuacion durante este periodo apenas ha sido estudiada. Metodo: Se evaluaron la neofobia gustativa y los procesos de memoria relacionados en ratas Wistar macho y hembra adolescentes (PND28) y adultas (PND70). En los Experimentos 1 y 2 Se exploro la atenuacion de la neofobia gustativa a soluciones de vinagre de sidra (3%) y sacarina sodica (0,1%), respectivamente. En los experimentos 3 y 4, se evaluo tambien la inhibicion latente de aversiones gustativas y la memoria de reconocimiento de objetos. Resultados: Adolescentes y adultos mostraron neofobia gustativa a la sacarina, pero las ratas adolescentes requirieron mas exposiciones a la solucion de vinagre para reconocerla como segura. No hubo diferencias entre los grupos en los Experimentos 3 and 4. No se hallaron efectos significativos del sexo. Conclusiones: A pesar de la ampliamente aceptada asociacion entre adolescencia y reducida neofobia, las ratas adolescentes muestran neofobia al sabor que resulta incluso incrementada cuando se trata de sabores acidos. Palabras clave: Adolescencia Atenuacion de la neofobia Sabor Memoria de reconocimiento Rata
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Gut microbiota has been linked to infant neurodevelopment. Here, an association between infant composite cognition and gut microbiota composition is established as soon as 6 months. Higher diversity ...and evenness characterize microbial communities of infants with composite cognition above (Inf-aboveCC) versus below (Inf-belowCC) median values. Metaproteomic and metabolomic analyses establish an association between microbial histidine ammonia lyase and infant histidine metabolome with cognition. Fecal transplantation from Inf-aboveCC versus Inf-belowCC donors into germ-free mice shows that memory, assessed by a novel object recognition test, is a transmissible trait. Furthermore, Inf-aboveCC mice are enriched in species belonging to Phocaeicola, as well as Bacteroides and Bifidobacterium, previously linked to cognition. Finally, Inf-aboveCC mice show lower fecal histidine and urocanate:histidine and urocanate:glutamate ratios in the perirhinal cortex compared to Inf-belowCC mice. Overall, these findings reveal a causative role of gut microbiota on infant cognition, pointing at the modulation of histidine metabolite levels as a potential underlying mechanism.
Hypercalcemia is a common complication in cancer patients Mainly caused by Parathyroid hormone-related protein (PTHrP) secretion and metastasis. Calcitriol secretion is a rare source of hypercalcemia ...in solid tumors, especially in gastrointestinal stromal tumors (GIST). We present a case report of a female patient with a 23 cm gastric GIST that expressed somatostatin-receptors and presented with severe hypercalcemia due to calcitriol secretion. Calcium control was achieved with medical treatment before the use of targeted-directed therapies. Surgery was performed and allowed complete tumor resection. Two years later, patient remains free of disease. Molecular analysis revealed the mRNA expression of 25-hydroxyvitamin D
-1-hydroxylase (1αOHase) and vitamin-D receptors in the tumor cells, confirming the calcitriol-mediated mechanism. Furthermore, the expression of the endotoxin recognition factors CD14 and TLR4 suggests an inflammatory mediated mechanism. Finally, the expression of somatostatin-receptors, especially
might have been related with clinical evolution and prognosis in this patient.
Hypercalcemia is a common complication in cancer patients Mainly caused by Parathyroid hormone-related protein (PTHrP) secretion and metastasis. Calcitriol secretion is a rare source of hypercalcemia ...in solid tumors, especially in gastrointestinal stromal tumors (GIST). We present a case report of a female patient with a 23 cm gastric GIST that expressed somatostatin-receptors and presented with severe hypercalcemia due to calcitriol secretion. Calcium control was achieved with medical treatment before the use of targeted-directed therapies. Surgery was performed and allowed complete tumor resection. Two years later, patient remains free of disease. Molecular analysis revealed the mRNA expression of 25-hydroxyvitamin D
3
-1-hydroxylase (1αOHase) and vitamin-D receptors in the tumor cells, confirming the calcitriol-mediated mechanism. Furthermore, the expression of the endotoxin recognition factors CD14 and TLR4 suggests an inflammatory mediated mechanism. Finally, the expression of somatostatin-receptors, especially
SST2
might have been related with clinical evolution and prognosis in this patient.
Readers have to track the knowledge of every character in a story. Sometimes errors occur and readers attribute their own privileged knowledge to a character.
Keysar (1994) studied this phenomenon in ...a communicative context. The task included stories in which one character writes an ambiguous message to another. Participants seemed to attribute the knowledge owned only by the writer character to the addressee of the message. One possible explanation for this phenomenon was based on the assumption that readers believe characters will strive to be cooperative: the message is ambiguous only for the external reader, while for the addressee it is informative enough, given their common knowledge. This explanation is tested in two experiments by introducing additional characters to the story: a third participant who had the privileged information but did not participate in the relevant communicative act and an accidental reader who interpreted the message. The illusory transparency in the intention to communicate persists but with important restrictions. The results are discussed following the alternative explanations given in the literature of perspective-taking.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
PDF
