Presents a laboratory experiment that examines the aggressive behavior of male paradise fish. Students design the experiment, collect data, and analyze and interpret the results. This activity is appropriate for biology, ecology, and animal behavior classes and allows students to be involved in the entire scientific process. (Author/NB)

Interviews university students in modern physics about their understanding of three fundamental experiments. Explores their development of models of microscopic processes. Uses interactive demonstrations to probe student understanding of modern physics experiments in two high school physics classes. Analyzes the nature of students' models and the…

Start at the end; that's the way to improve children's plans for investigations. Strange as it may seem, there are times when beginning at the beginning of an investigation is not the best way to start things off. To give children the opportunity to ask questions and plan what to do, sometimes it is best to get them first to consider others' data…

During one school year, data were collected for vocational education students while they worked collaboratively on open-ended mathematics problems. In collaboration with participating teachers, instructional activities were designed with a twofold goal of modelling the process of problem solving and improving collaboration. Instructional…

An important unanswered question in the empirical literature on trust is whether trusting begets trustworthiness. In two experimental games, with Japanese and American participants, respectively, we compared trust and trustworthiness to provide an answer to this question. The trustee in the standard Trust Game knows that he or she is trusted,…

Models of speech production disagree on whether or not homonyms have a shared word-form representation. To investigate this issue, a picture-naming experiment was carried out using Dutch homonyms of which both meanings could be presented as a picture. Naming latencies for the low-frequency meanings of homonyms were slower than for those of the…

We examined the contribution of semantic similarity to morphological priming effects, using the immediate (Exp. 1 and 3) and the delayed variant (Exp. 2) of picture-word interference. Distractor words were either compounds morphologically related to the picture name, but differing with respect to their semantic transparency (hummingbird, jailbird…

This study examined infants' enumeration of puppet jumping tasks. In Experiment 1, 5-7-month-old infants were familiarized to a puppet jumping two or three times, and tested with both numbers of jumps. Infants looked significantly longer at the new number, replicating Wynn [Psychol. Sci. 7 (1996) 164]. To probe further the stability of infants'…

Visual speech cues presented in synchrony with discrepant auditory speech cues are usually combined to a surprisingly clear unitary percept that corresponds with neither of the two sensory inputs (the McGurk illusion). This audiovisual integration process is commonly believed to be highly autonomous and robust to cognitive intervention, unlike the…

Violins, earthquakes, and the "singing rod" demonstration all have something in common--stick-slip frictional motion. The application of stick-slip friction can be extended to a ringing wineglass, exotic percussion instruments, car racing, and the latest research on the interplay between surfaces at the atomic level. These examples all involve two…

Switching between tasks produces decreases in performance as compared to repeating the same task. Asymmetrical switch costs occur when switching between two tasks of unequal difficulty. This asymmetry occurs because the cost is greater when switching to the less difficult task than when switching to the more difficult task. Various theories about…

This article focuses on a small experiment initiated by two three-year-old preschool children without the instruction or supervision of a teacher, while playing in the yard. During their playtime, they began to color the blacktop with chalk. They thought of a brilliant idea of pouring water over the chalk drawings and after the water dries up,…

Do locomotor after effects depend specifically on visual feedback? In 7 experiments, 116 college students were tested, with closed eyes, at stationary running or at walking to a previewed target after adaptation, with closed eyes, to treadmill locomotion. Subjects showed faster inadvertent drift during stationary running and increased distance…

Hierarchical graphs represent relationships between objects (like computer file systems, family trees etc.). Graph nodes represent the objects and interconnecting lines represent the relationships. In two experiments we investigated what concepts are necessary for understanding hierarchical graphs, what misconceptions evolve when some of the…

Cinemicrography--the capture of moving cellular sequences through the microscope--has been influential in revealing the dynamic nature of cellular behavior. One of the more dramatic cellular events is mitosis, the division of sister chromatids into two daughter cells. Mitosis has been extensively studied in a variety of organisms, both…