RESUMEN
In Experiment 1 the behaviour of black-capped chickadees timing intervals of 12.5 or 37.5 s was studied using the peak procedure. Average rate of responding peaked near the trained FI on test trials, while the spread of the response distribution was larger for the longer FI. On individual trials, chickadees showed a break-run-break pattern of abrupt changes in rate of responding. These results, plus the pattern of means, standard deviations, and correlations found in start times, stop times, and durations of runs, were similar to those found in pigeons and rats. This suggests that birds and rodents use similar timing mechanisms. In Experiment 2, chickadees were tested with an interrupted FI signal. On such 'gap' trials, the chickadees, like pigeons but unlike rats tested under similar parameters, ignored the signal time elapsed prior to the FI interruption and reset the interval clock.
RESUMEN
It has been suggested that the system behind implicit memory in humans is evolutionarily old and that animals should readily show priming. In Experiment 1, a picture fragment completion test was used to test priming in pigeons. After pecking a warning stimulus, pigeons were shown 2 partially obscured pictures from different categories and were always reinforced for choosing a picture from one of the categories. On control trials, the warning stimulus was a picture of some object (not from the S+ or S- category), on study trials the warning stimulus was a picture to be categorized on the next trial, and on test trials the warning stimulus was a randomly chosen picture and the S+ picture was the warning stimulus seen on the previous trial. Categorization was better on study and test trials than on control trials. Experiment 2 ruled out the possibility that the priming effect was caused by the pigeons' responding to familiarity by using warning stimuli from both S+ and S- categories. Experiment 3 investigated the time course of the priming effect.
Asunto(s)
Atención , Concienciación , Recuerdo Mental , Reconocimiento Visual de Modelos , Enmascaramiento Perceptual , Animales , Columbidae , Solución de ProblemasRESUMEN
Differences in neuroanatomy, optics, and function indicate the operation of 2 visual systems in pigeons, a frontal field system and a lateral field system. Communication between these systems was examined with a delayed matching-to-sample task in which sample stimuli could be presented in either the frontal or lateral fields. In Experiment 1, matching acquired with the lateral field transferred to the frontal field but did not transfer from the frontal field to the lateral field. When different samples were presented simultaneously to the frontal and lateral fields in Experiment 2, pigeons preferred to match the sample in the frontal field, but lateral field information interfered to some extent with frontal field matching. The 3rd experiment showed left lateral field dominance when the left and right fields were simultaneously presented with different sample stimuli; left field dominance was not complete, as pigeons sometimes matched the right-field sample.