Learn More
Four pigeons discriminated whether a target spot appeared on a colored figural shape or on a differently colored background by first pecking the target and then reporting its location: on the figure or the background. We recorded three dependent variables: target detection time, choice response time, and choice accuracy. The birds were faster to detect the(More)
It is said that "absence makes the heart grow fonder." But, when and why does an absent event become salient to the heart or to the brain? An absent event may become salient when its nonoccurrence is surprising. Van Hamme and Wasserman (1994) found that a nonpresented but expected stimulus can actually change its associative status-and in the opposite(More)
Recent research has shown that the acquisition of a second cue–outcome association can interfere with responding appropriate to a previously acquired association between another cue and the same outcome, even if the two cues had never received compound training (Matute & Pineño, 1998a). This is similar to other results in the paired-associate literature but(More)
For many decades, developmental and comparative psychologists have used a variety of string tasks to assess the perceptual and cognitive capabilities of human children of different ages and different species of nonhuman animals. The most important and widely used of these problems are patterned-string tasks, in which the organism is shown two or more(More)
Prior research suggests that variability discrimination is basic to same-different conceptualization (Young and Wasserman, 2001). In that research, people were trained with 16-item arrays; this training might have encouraged people to use perceptual variability to solve the task. Here, two groups of participants were trained with either 2- or 16-item Same(More)
In Tribolium castaneum (CS) and T. confusum (CF), intra- and interspecific rates of homosexual mounting have been measured. The intraspecific results are compatible with the hypothesis of both species being sexually indiscriminate. However, the CF intraspecific rates were very high (35%-53% of mountings were homosexual), suggesting a lower sexual(More)
Previous studies showed that the anterior cingulate cortex (ACC) plays a role in selective visual attention. The current study further examined the role of the ACC in attention using a visual cuing task with task-relevant and task-irrelevant stimuli. On every trial, 2 stimuli were presented on the touchscreen; 1 was task-relevant and the other was(More)
We explored college students' discrimination of complex visual stimuli that involvedmultiple-item displays. The items in each of the displays could be all the same, all different, or diverse mixtures of some same and some different items. The participants had to learn which of two arbitrary responses was correct for each of the displays without being told(More)
Because of the importance of the sense of sameness for psychological science and because of the tenuous support for this notion in pigeons’ matching-to-sample behavior, we experimentally explored the possibly special status of sameness for pigeons. Using photographs from three different natural categories (dogs, fish, and flowers) in a three-alternative(More)