The origins of many of the basic concepts used in the experimental analysis of behavior can be traced to Pavlov's (1927/1960) discussion of unconditional and conditional reflexes in the dog, but often with substantial changes in meaning (e.g., stimulus, response, and reinforcement). Other terms were added by Skinner (1938/1991) to describe his…

Three pigeons discriminated between two sample stimuli (intensities of red light). The difficulty of the discrimination was varied over four levels. At each level, the relative reinforcer magnitude for the two correct responses was varied across conditions, and the reinforcer rates were equal. Within levels, discriminability between the sample…

Two experiments investigated the derived transfer of functions through equivalence relations established using a stimulus pairing observation procedure. In Experiment 1, participants were trained on a simple discrimination (A1+/A2-) and then a stimulus pairing observation procedure was used to establish 4 stimulus pairings (A1-B1, A2-B2, B1-C1,…

Two experiments used a mutual imitation paradigm to assess 9-, 14-, and 18-month-old infants' developing understanding of intentions in others. In the first study, 1 experimenter imitated the infants' actions, and another experimenter performed contingent but different actions on an identical toy. From 9 months of age, infants show discrimination…

The characteristics of scanning patterns between the ages of 6 and 26 weeks were investigated through repeated assessments of 10 infants. Eye movements were recorded using a corneal-reflection system while the infants looked at 2 dynamic stimuli: the naturally moving face of their mother and an abstract stimulus. Results indicated that the way…

A rather consistent finding in studies of perceived (imagined) compared to actual movement in a reaching paradigm is the tendency to overestimate at midline. Explanations of such behavior have focused primarily on perceptions of postural constraints and the notion that individuals calibrate reachability in reference to multiple degrees of freedom,…

People presume that the light source in pictures comes from above, and there is some evidence that this phenomenon also demonstrates lateral biases. When investigators present multiple ambiguous stimuli or visually complex objects, people assume that the source of light is from above, and to the left. However, when single relatively simple stimuli…

Mand functions for two stimuli (A1 and A2) were trained for 3 children with autism and were then incorporated into two related conditional discriminations (A1-B1/A2 -B2 and B1-C1/B2-C2). Tests were conducted to probe for a derived transfer of mand response functions from Al and A2 to C1 and C2, respectively. When 1 participant failed to…

Functional communication training (FCT) is a widely used treatment for individuals with developmental disabilities who exhibit severe behavior problems. One inherent challenge of employing FCT as a treatment in the community is that reinforcement for appropriate communication cannot always be immediate or even possible in some circumstances. Of…

Glickman, Gray, and Morales (this issue) propose a statistical model for measuring the unobserved latency of stimulus-controlled processes. The model accounts for both speed and accuracy and does so by assuming that participants set an internal deadline. If a stimulus-controlled response is not produced by the deadline, the participant then…

Research evidence indicates that self-report imagery ability is psychometrically distinct from objective, spatial test measures. One hypothesis put forward in the literature to explain this finding is that the nature of the stimulus is important. The aim of this article was to examine the relation between spatial abilities and measures of visual…

The present study investigated how anticipation of a target's appearance affects human attention to gaze cues provided by a schematic face. Subjects in a "catch" group received a high number of "catch" trials, in which no target stimulus appeared. Subjects in the control group did not receive any catch trials. As in previous studies, both groups…

Developmental prosopagnosia (DP) is a severe impairment in identifying faces that is present from early in life and that occurs despite no apparent brain damage and intact visual and intellectual function. Here, we investigated what aspects of face processing are impaired/spared in developmental prosopagnosia by examining a relatively large group…

We report an experiment in which subjects named 120 pictures, consisting of series of five pictures drawn from each of 24 semantic categories (and intermixed with 45 fillers). The number of intervening trials (lag) between successive presentations of members of the same category varied from two to eight. Subjects' naming latencies were slowed by…

Humans see whole objects from input fragmented in space and time, yet spatiotemporal object perception is poorly understood. The authors propose the theory of spatiotemporal relatability (STR), which describes the visual information and processes that allow visible fragments revealed at different times and places, due to motion and occlusion, to…