Categorical perception (CP) effects manifest as faster or more accurate discrimination between objects that come from different categories compared with objects that come from the same category, controlling for the physical differences between the objects. The most popular explanations of CP effects have relied on perceptual warping causing…

Feedback is highly contingent on behavior if it eventually becomes easy to predict, and weakly contingent on behavior if it remains difficult or impossible to predict even after learning is complete. Many studies have demonstrated that humans and nonhuman animals are highly sensitive to feedback contingency, but no known studies have examined how…

Compared to text, diagrams are superior in their ability to structure and summarize information and to show relations between concepts and ideas. Perceptual cues, like arrows, are expected to improve the retention of diagrams by guiding the learner towards important elements or showing a preferred reading sequence. In our experiment, we analyzed…

The findings of Shepard, Hovland, and Jenkins (1961) on the relative ease of learning 6 elemental types of 2-way classifications have been deeply influential 2 times over: 1st, as a rebuke to pure stimulus generalization accounts, and again as the leading benchmark for evaluating formal models of human category learning. The litmus test for models…

Previous research has demonstrated that visual properties of objects can affect shape-based categorization in a novel-name extension task; however, we still do not know how a relationship between visual properties of objects affects judgments in a novel-name extension task. We examined effects of increased visual similarity among the target and…

Since it was first published 30 years ago, the seminal paper of Chi "et al." on expert and novice categorization of introductory problems led to a plethora of follow-up studies within and outside of the area of physics [Cogn. Sci. 5 121 (1981)]. These studies frequently encompass "card-sorting" exercises whereby the…

Face perception studies investigated how spatial frequencies (SF) are extracted from retinal display while forming a perceptual representation, or their selective use during task-imposed categorization. Here we focused on the order of encoding low-spatial frequencies (LSF) and high-spatial frequencies (HSF) from perceptual representations into…

A recent resurgence in logical-rule theories of categorization has motivated the development of a class of models that predict not only choice probabilities but also categorization response times (RTs; Fific, Little, & Nosofsky, 2010). The new models combine mental-architecture and random-walk approaches within an integrated framework and…

Cantonese shape classifiers encode perceptual information that is characteristic of their associated nouns, although certain nouns are exceptional. For example, the classifier "tiu" occurs primarily with nouns for long-narrow-flexible objects (e.g., scarves, snakes, and ropes) and also occurs with the noun for a (short, rigid) key. In 3…

A contrast category effect on categorization occurs when the decision to apply a category term to an entity not only involves a comparison between the entity and the target category but is also influenced by a comparison of the entity with 1 or more alternative categories from the same domain as the target. Establishing a contrast category effect…

The minimal control principle (Taatgen, 2007) predicts that people strive for problem-solving strategies that require as few internal control states as possible. In an experiment with the Abstract Decision Making task (ADM task; Joslyn & Hunt, 1998) the reward structure was manipulated to make either a low-control strategy or a high-strategy…

In 3 experiments, the role of item strength in the retrieval-induced forgetting paradigm was tested. According to the inhibition theory of forgetting proposed by M. C. Anderson, R. A. Bjork, and E. L. Bjork (1994), retrieval-induced forgetting should be larger for items that are more strongly associated with the category cue. In the present…

This article describes an easy and cheap laboratory exercise for students to discover their own mitochondrial haplogroup. Students use buccal swabs to obtain mucosa cells as noninvasive tissue samples, extract DNA, and with a simple polymerase chain reaction-restriction fragment length polymorphism analysis they can obtain DNA fragments of…

In four experiments, we investigated whether masked stimuli in priming experiments are subjected to early or to late selection. In Experiment 1, participants classified four target-pictures as being small or large. In line with early selection accounts, prime-pictures with a different perceptual appearance as the experienced targets did not elicit…

Humans have an extremely flexible ability to categorize regularities in their environment, in part because of attentional systems that allow them to focus on important perceptual information. In formal theories of categorization, attention is typically modeled with weights that selectively bias the processing of stimulus features. These theories…