After haptic habituation to a ring display, infants perceived the rings in two experiments as parts of one connected object. In both haptic and visual modes, infants appeared to perceive object unity by analyzing motion but not by analyzing figural goodness. (RH)

A model for solution of the motion correspondence problem is presented that is capable of maintaining the identities of individuated elements as they move. Many properties of the model are consistent with what is known about physiological mechanisms underlying human motion perception. (SLD)

The 1954 review of visual motion perception by James J. GIbson anticipated future developments in the field, but these developments were achieved without closely following Gibson's ideas. Reasons for the dormancy of his ideas are explored, and contemporary work on motion perception is evaluated from Gibson's perspective. (SLD)

In 4 experiments, the authors investigated spatial updating in a familiar environment. Participants learned locations of objects in a room, walked to the center, and turned to appropriate facing directions before making judgments of relative direction (e.g., "Imagine you are standing at X and facing Y. Point to Z.") or egocentric pointing…

Infants expect objects to be solid and cohesive, and to move on continuous paths through space. In this study, we examine whether infants understand that human beings are material objects, subject to these same principles. We report that 5-month-old infants apply the constraint of continuous motion to inanimate blocks, but not to people. This…

We treat a modified Atwood's machine in which equal masses do not balance because of being in an accelerated frame of reference. Analysis of the problem illuminates the meaning of inertial forces, d'Alembert's principle, the use of free-body diagrams and the selection of appropriate systems for the diagrams. In spite of the range of these…

In this paper, a new dance training system based on the motion capture and virtual reality (VR) technologies is proposed. Our system is inspired by the traditional way to learn new movements-imitating the teacher's movements and listening to the teacher's feedback. A prototype of our proposed system is implemented, in which a student can imitate…

We have recently developed and implemented two experiments in biomolecular NMR for an undergraduate-level biophysical chemistry laboratory with commercially available [superscript 15]N-enriched human ubiquitin. These experiments take advantage of [superscript 15]N direct detection of the NMR signal. The first experiment develops skills in…

While five-month-old infants show orientation-specific sensitivity to changes in the motion and occlusion patterns of human point-light displays, it is not known whether infants are capable of binding a human representation to these displays. Furthermore, it has been suggested that infants do not encode the same physical properties for humans and…

The importance of kinematics in emotion perception from body movement has been widely demonstrated. Evidence also suggests that the perception of biological motion relies to some extent on information about spatial and spatiotemporal form, yet the contribution of such form-related cues to emotion perception remains unclear. This study reports, for…

Our physics students like to watch a ball bouncing underwater. They do this by dropping a weighted plastic ball into a 1000-ml cylinder filled with a linearly stratified salt-water solution at room temperature. The ball oscillates and comes to rest at about mid-depth. Its motion is analogous to the damped vertical oscillations of a mass hanging…

Potato cannon velocity can be measured with a digitized microphone signal. A microphone is attached to the potato cannon muzzle, and a potato is fired at an aluminum target about 10 m away. Flight time can be determined from the acoustic waveform by subtracting the time in the barrel and time for sound to return from the target. The potato…

Turnout is a vital element of many dance techniques. Aesthetically, turnout is used to fulfill artistic goals related to body line and design. Mechanically, it increases the potential range of movement in certain leg gestures and facilitates movements sideways through space. Turnout involves external rotation of the femur along its long axis in…

Standing and walking generate information about friction underfoot. Five experiments examined whether walkers use such perceptual information for prospective control of locomotion. In particular, do walkers integrate information about friction underfoot with visual cues for sloping ground ahead to make adaptive locomotor decisions? Participants…

The purpose was to examine the differences in kinesthetic ability, at the elbow joint, between children with (n = 15) and without (n = 15) spastic hemiplegia. The Kin Com 125 AP isokinetic dynamometer Configuration Chattanooga was used. Results revealed significant (p less than 0.05) interaction between participant groups and side which was a…