When the road is wet (there is a water layer on the road surface), the road marks become blurred and drivers are distracted. We discuss the contributing processes and identify which processes are dominant to the occurrence of this phenomenon. Modelling and a simple experiment demonstrate that the dominant processes are: (a) refraction of light by…

A fundamental issue in the design and the interpretation of experimental studies of perception relates to the question of whether the participants in these experiments could perform the perceptual task assigned to them using another feature, or cue, than that intended by the experimenter. An approach frequently used by auditory- and…

Historically, the bodily senses have often been regarded as impeccable sources of spatial information and as being the teacher of vision. Here, the authors report that the haptic perception of slope by means of the foot is greatly exaggerated. The exaggeration is present in verbal as well as proprioceptive judgments. It is shown that this…

A simple low cost demonstration experiment is performed using common apparatus in order to show various flexural patterns and to give a dynamical measure of Young's modulus. (Contains 4 figures.)

Some models of object recognition propose that items from structurally crowded categories (e.g., living things) permit faster access to superordinate semantic information than structurally dissimilar categories (e.g., nonliving things), but slower access to individual object information when naming items. We present four experiments that utilize…

Previous reports have demonstrated that the comprehension of sentences describing motion in a particular direction (toward, away, up, or down) is affected by concurrently viewing a stimulus that depicts motion in the same or opposite direction. We report 3 experiments that extend our understanding of the relation between perception and language…

Describes a perceptual illusion, the Janus mask, for use in introductory psychology demonstrations. Suggests using a motor or videotaped image to rotate the mask, giving the impression that the mask is following a moving observer or oscillating. Recommends the illusion to show that perception is usefully conceptualized as hypothesis testing. (DK)

This article examines how the human visual system represents the shapes of 3-dimensional (3D) objects. One long-standing hypothesis is that object shapes are represented in terms of volumetric component parts and their spatial configuration. This hypothesis is examined in 3 experiments using a whole-part matching paradigm in which participants…

Four experiments are reported exploring whether distractor pictures activate their phonological properties in the course of speech production. In Experiment 1, participants were presented with two pictures and were asked to name one while ignoring the other. Distractor pictures were phonologically related, semantically related or unrelated to the…

We report four experiments designed to determine whether visual information affects judgments of acoustically-specified nonspeech events as well as speech events (the "McGurk effect"). Previous findings have shown only weak McGurk effects for nonspeech stimuli, whereas strong effects are found for consonants. We used click sounds that…