RESUMEN
Psychophysical methods allow us to measure the relationship between stimuli and sensory perception. Of these, Detection Threshold (DT) allows us to know the minimum concentration to produce taste identification. Given this, we wonder whether, for example, wine tasting experts are more capable of perceiving their sensory properties than other people, or whether they can distinguish them because they are better able to "describe" them. To verify this, this study analyses the influence of having prior knowledge of the name astringency and, failing that, to detect it and distinguish it between the four basic tastes. One-hundred-and-sixty-two university students with an average age of 19.43 (SD = 2.55) years were assigned to three experimental conditions: an experimental group (G.2) without previous knowledge of the name astringency and with alimentary satiety, and two control groups, both with previous knowledge of the name, these being G.1, with satiety, and G.3, with hunger. DT was collected for the four basic tastes and astringencies. Results showed significant differences in the identification of astringency, being the least identified experimental group with respect to the control groups. It is striking that G.2, without prior knowledge of the name, identified astringency as a bitter taste in most cases. This supports our hypothesis of the importance of attending to linguistic cognitive processes when psychophysically estimating taste in humans.
RESUMEN
The Iowa gambling task (IGT) is an instrument for the neuropsychological evaluation of cognitive and emotional decision making (DM) processes that was created to test the somatic marker hypothesis (SMH) described by Damasio in 1994. It was initially applied to patients with frontal lobe lesions due to its association with executive functions but was subsequently used on patients with a variety of disorders. Although the DM process is inherently perceptual, few studies have applied the IGT to examine DM processes in patients with eating disorders (EDs), and even fewer have associated the IGT to the perceptual distortion of body image (PDBI) in this population. People diagnosed with ED exhibit heightened control over their somatic responses-for example, they can delay digestion for hours-and DM may be affected in this condition. This study compares the performance of two samples of adolescent women-hospitalized patients with ED, and healthy controls with similar demographic characteristics-on the IGT using body image as a possible factor in the SMH. Seventy-four women with a mean age of 14.97 years (SD = 2.347) participated. To analyze their body self-image, we used the figure-rating scale and compared the results with their body mass index (BMI). Correlations between indices of the IGT and distortion in body image were then explored. The results revealed significant differences between the groups in terms of evolving performance on the partial IGT. Patients with ED performed worse than their healthy counterparts in the last 40 trials and exhibited greater distortions in their body image, especially in terms of overestimation. Indices of these distortions were negatively correlated with the total IGT. These results are compatible with the SMH because they suggest that patients with ED evinced blindness with regard to the future, as described by their authors. In addition, a negative correlation was found between the IGT and PDBI, showing that a more distorted body image was associated with lower IGT, that is, more disadvantageous or riskier decisions were made by the subjects with more distortion.
RESUMEN
INTRODUCTION: in sensory perception of taste, it is difficult to learn the concepts of absolute threshold (AT), the psychophysical methods to estimate it and the influence exerted by prior knowledge on their perception and recognition, because they have little awareness. OBJECTIVE: to assess absolute thresholds of four basic flavors in a sample of healthy young people, in conditions of food restriction/without restriction, and to analyze the influence of prior knowledge of astringency in its detection-identification. METHODS: one hundred and fourteen participants with an average of 20.03 years old (SD = 5.45), 75.4% of them women, were put in direct contact with chemical substances of basic flavors and astringency through a theoretical-practical tasting. An inverted treatment design was applied with experimental conditions on food restriction and knowledge of astringency. RESULTS: all identified their AT for basic flavors. The group with restriction was significantly more sensitive (Tb = -3.305, p = 0.001) to sweet (AU = 2 g/l) than the group without restriction (AU = 5 g/l). The detection-identification of astringency was significantly higher (t = -13.323, p = 0.000) with previous information of the name (79.31%) than without this information (19.64%), confusing or describing it as bitter taste (80.36). CONCLUSION: taste learning is facilitated with the performance of psychophysical measurements of chemical senses, together with training of certain theoretical concepts about taste perception and flavor denomination, because it facilitates the cognitive process for detection-identification. In addition, the process for the previous internal homeostasis of participants must be considered as their AU results vary according to the hunger/satiety conditions prior to the psychophysical estimation.
INTRODUCCIÓN: en la percepción sensorial del gusto, los conceptos de umbral absoluto (UA), los métodos psicofísicos para estimarlo y la influencia que ejerce el conocimiento previo sobre su percepción y reconocimiento son de difícil aprendizaje por su escaso estado de conciencia. OBJETIVO: evaluar los umbrales de detección de los cuatros sabores básicos en una muestra de jóvenes sanos, en condiciones de restricción de alimentos/no-restricción, y analizar la influencia del conocimiento previo de la astringencia para su detección-identificación. MÉTODO: se puso en contacto directo con las sustancias químicas de los sabores y de astringencia a 114 participantes con media de 20,03 años (DT = 5.45), el 75,4% mujeres, mediante una degustación teórica-práctica. Se aplicó un diseño de tratamiento invertido con las condiciones experimentales sobre restricción de alimentos y conocimiento de astringencia. RESULTADOS: todos identificaron sus UA para los cuatro sabores básicos. El grupo con restricción fue significativamente más sensible (Tb = -3,305; p = 0,001) al dulce (UA = 2 g/l) que el grupo sin restricción (UA = 5 g/l). La detección-identificación de la astringencia resultó significativamente mayor (t = -13,323; p = 0,000) con información previa del nombre (79,31%) que sin esta información (19,64%), confundiéndola, o describiéndola, como sabor amargo (80,36%). CONCLUSIONES: el aprendizaje del sabor se favorece cuando se realiza la medición psicofísica de los sentidos químicos junto a la formación de determinados conceptos teóricos sobre la percepción gustativa y denominación de sabores, al facilitar su proceso cognitivo posterior detección- identificación. También debe atenderse al proceso de homeostasis interna previa de los participantes por la variabilidad en los resultados de sus UA según las condiciones de hambre/saciedad anteriores a su estimación psicofísica.