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Kosuke Sawa

Publications and source records attributed to Kosuke Sawa.

3 recordsLinked to original sources

Causal reasoning in rats.

Empirical research with nonhuman primates appears to support the view that causal reasoning is a key cognitive faculty that divides humans from animals. The claim is that animals approximate causal learning using associative processes. The present results cast doubt on that conclusion. Rats made causal inferences in a basic task that taps into core features of causal reasoning without requiring complex physical knowledge. They derived predictions of the outcomes of interventions after passive observational learning of different kinds of causal models. These competencies cannot be explained by current associative theories but are consistent with causal Bayes net theories.

Animals↗

Sensory preconditioning in spatial learning using a touch screen task in pigeons.

The authors used a touch screen-based visual-search task to investigate spatial integration in pigeons. First, pigeons were presented with a consistent spatial relationship between compound visual landmarks (LMs) A-X and B-Y, separately. Next, pigeons learned to find a hidden goal on the monitor in the presence of LMs A and B. The goal bore a consistent spatial relationship to LM A, but not to LM B. On nonreinforced probe tests, the peak and distribution of responses to LM X suggest that pigeons computed a novel X-goal spatial relationship on the basis of X-A and A-goal spatial vectors. Responses to LM Y, however, revealed no evidence of spatial integration. These results replicate and extend those of A. P. Blaisdell and R. G. Cook (2005) using an open-field task.

Animals↗

Acquired equivalence of flavour cues with a common antecedent in rats.

Equivalence of flavour cues, each of which had been paired with a common antecedent, was demonstrated with rats in a three-stage design. In the first stage, a group of thirsty rats were given each of two target flavour cues after a common antecedent flavour (Xright arrowA and Xright arrowB), while a second group of rats were given A and B after differential antecedent flavours (Xright arrowA and Yright arrowB). Another group of rats was allowed to drink A and B after familiar tap water. In the second stage, aversion to A was established by a lithium chloride injection after drinking A. The acquired equivalence effect was verified in the third stage by strong aversion to B in the group trained with the common antecedent compared with the remaining two groups. The representation-mediation, rather than response-mediation, hypothesis seems to fit the backward acquired equivalence effect obtained here.

Journal Article↗