Los resultados encontrados en situaciones de elección entre animales humanos y no humanos son en algunos casos contradictorios. Se han propuesto dos posibles explicaciones: (1) los procesos de elección son diferentes en animales humanos y no humanos o (2) los procedimientos utilizados para el estudio de la elección en unos y otros no son comparables. Particularmente, en humanos se observan mayores tiempos de respuesta a medida que se incrementa el número de alternativas que constituyen el contexto de elección. Esto ha sido interpretado como evidencia a favor de un proceso de comparación entre las alternativas presentadas. Sin embargo, estudios recientes con estorninos han encontrado resultados opuestos. Para dar razón de estos resultados se ha propuesto el Modelo de Elección Secuencial, que no asume la existencia de un proceso de comparación y permite realizar predicciones concretas en situaciones de elección momento a momento. Se diseñó una tarea equivalente a las empleadas con animales no humanos para su presentación en humanos. Los resultados apoyaron parcialmente las predicciones del Modelo de Elección Secuencial si bien no permiten descartar la existencia de un mecanismo de comparación en humanos.

Several studies in pigeons and rats have reported a predictable relation between latencies during no-choice trials and the ulterior preference in choice trials. The Sequential Choice Model (SCM) was proposed in 2008 to account for these results, and more importantly to make precise predictions about the correlation between latency and preference. Eight male Wistar rats were exposed to 48 sessions in a risk-sensitive procedure, each session was composed by 10 blocks of trials (2 no-choice and 4 choice trials). We analyzed data taking latencies of response and testing the SCM’s predictions. Our data support partially the SCM’s predictions, but a monotonic decrease to a floor effect in all latencies of response does not allow confirming all predictions. The results are discussed regarding a decrease in the valuation cost as a result of extended exposure, and arguing that diminishing latencies in this particular procedure contributed to increase the whole rate of reinforcement.

The preferences of organisms faced with changing conditions in food delivery situations have been studied under the rubric of risk-sensitivity. Optimal foraging theory often applies the energy budget model to explain the preferences shown by organisms, but in this paper we suggest a different approach, one based on the study of individual differences. A sample of rats was classified as high and low novelty-seeking. Afterwards, they were maintained at 75% or 90% of their body weight and exposed to a risk-sensitivity procedure. The results show that the novelty-seeking model is associated with different patterns of preference under a risk-sensitivity procedure, but that these patterns do not correlate with the level of food deprivation employed. Furthermore, we found that the spontaneous alternation between options in a choice situation correlates with the organism’s preference during a risk procedure. Considering recent findings in the area of animal and human decision-making, our results are explained in terms of altered behavioral processes.