Biomedical subjects

Joshua S Beckmann

Publications and source records attributed to Joshua S Beckmann.

3 recordsLinked to original sources

PubMed2007

The feature positive effect in the face of variability: novelty as a feature.

Past literature has shown, across various methods and species, that feature positive (FP) tasks (AB-/B+) are learned more easily than are feature negative (FN) tasks (AB-/B+), giving rise to what is known as the feature positive effect (FPE). Experiment 1 was intended to assess the role of expected absence in the FPE through manipulation of the context (constant vs. varied common elements) that was paired with the feature. The results indicate that novel contextual elements (varied common elements) may be salient enough to eliminate the FPE, creating a feature negative effect (FNE). Experiment 2 replicated the FNE. The addition of a testing phase confirmed that participants in the FN task judged novel stimuli to be strong positive predictors whereas participants in the FP task did not, thus producing a novelty FPE. These results are problematic for contemporary associative learning models.

Adult↗

PubMed2006

Pigeons' discrimination of Michotte's launching effect.

We trained four pigeons to discriminate a Michotte launching animation from three other animations using a go/no-go task. The pigeons received food for pecking at one of the animations, but not for pecking at the others. The four animations featured two types of interactions among objects: causal (direct launching) and noncausal (delayed, distal, and distal & delayed). Two pigeons were reinforced for pecking at the causal interaction, but not at the noncausal interactions; two other pigeons were reinforced for pecking at the distal & delayed interaction, but not at the other interactions. Both discriminations proved difficult for the pigeons to master; later tests suggested that the pigeons often learned the discriminations by attending to subtle stimulus properties other than the intended ones.

Animals↗

PubMed2005

Causal impressions: predicting when, not just whether.

In 1739, David Hume established the so-called cues to causality--environmental cues that are important to the inference of causality. Although this descriptive account has been corroborated experimentally, it has not been established why these cues are useful, except that they may reflect statistical regularities in the environment. One of the cues to causality, covariation, helps predict whether an effect will occur, but not its time of occurrence. In the present study, evidence is provided that spatial and temporal contiguity improve an observer's ability to predict when an effect will occur, thus complementing the utility of covariation as a predictor of whether an effect will occur. While observing Michotte's (1946/1963) launching effect, participants showed greater accuracy and precision in their predictions of the onset of movement by the launched object when there was spatial and temporal contiguity. Furthermore, when auditory cues that bridged a delayed launch were included, causal ratings and predictability were similarly affected. These results suggest that the everyday inference of causality relies on our ability to predict whether and when an effect will occur.

Cognition↗