While it is clear that schizophrenic patients often exhibit disordered thinking, the specific nature of the deficit and its role, either as a basis of abnormal behavior or as a symptom of malfunction in some underlying control process, remain to be clarified by research and by theory. Describes two experiments on the performance of conceptual…

These experiments consider the effects of aging on response times to stimuli of increasing complexity in serial choice RT tasks, whether age differences were reduced or abolished on such tasks, and examines repetition effects of a particular coding rule. (Author/RK)

A two-process theory of the spacing (lag) effect in free recall is presented and tested. (Editor/RK)

Smaller amounts of materials are used in organic chemistry experiments as a means of improving air quality in the laboratory. Outlines benefits from this approach and describes two representative experiments in detail. These experiments are the Cannizzaro reaction and preparation of an aromatic nitrile. (JN)

Two demonstrations are described. The first (useful as an introduction to kinetics) shows how the rate of a reaction is fast at first and then gradually decreases to zero when one reactant has been used up. The second is a gas density demonstration using 1,1,2-trichloro-1,2,2-trifluoro ethane. (JN)

Shows how a standard slide projector can be adapted for use as an effective spectroscope. Also describes three experiments using the modified slide projector. (JN)

The moving pattern that appears on an oscilloscope screen is used to illustrate two kinds of wave motion and the relationship between them. Suggestions are presented for measuring wavelength, frequency, phase shift, and phase velocity in this college-level laboratory exercise. (DH)

Presented is a method of demonstrating the optical activity of glucose using an overhead projector and easily obtainable materials. Explores the difference between reflected and transmitted light (Tyndall Effect) using sodium thiosulfate, hydrochloric acid, and an overhead projector. (ML)

Describes the nine modules of the SAVI/SELPH program, a hands-on, multisensory science program developed for grade 4-7 visually impaired, orthopedically disabled, learning disabled, deaf, and multihandicapped students. Modules consist of measurement, structures of life, scientific reasoning, communication, magnetism and electricity, mixtures and…

Presents experiments using wild birds as predators and pastry as prey and colored stones as background to demonstrate natural selection. Describes the exercise as an exercise in simulating natural selection. (Author/CW)

Outlines a laboratory exercise that makes use of Beer's Law plots of cysteine constructed at several pH values over a broad range of wavelengths to estimate the tautomeric ratio (R) of two singly charged ionic forms, calculate the microscopic constants, and construct ultraviolet spectra for both light absorbing species. (CW)

Described is a Monte-Carlo method for modeling physical systems with a computer. Also discussed are ways to incorporate Monte-Carlo simulation techniques for introductory science and mathematics teaching and also for enriching computer and simulation courses. (RH)

Discusses the possibilities of toxins present in medicinal herbs. Describes an experiment in which toxic constituents can be selectively detected by thin-layer chromatography and NMR spectroscopy. (TW)

Discusses the uses of thermistors in teaching electronics and semiconductors. Describes how to experimentally measure and graph the characteristics of a thermistor. Suggests one possible approach to understand the shapes of the characteristics. (CW)

Explains the use of an accelerometer in investigations confirming Newton's second law. Provides diagrams and descriptions of the apparatus. (ML)