A microcomputer-controlled laboratory: Software

The software used in a microcomputer-controlled laboratory is described. Primary emphasis is placed upon describing the capabilities of a powerful, easy-to-use programming language appropriate for controlling research in a wide variety of applications. It is particularly appropriate for physiological and operant laboratories. Design of the language and accompanying operating system follow a rigorous modular, structured approach, with most coding done in high-level languages. As a result, the code is easy to maintain and expand. In addition, it is not difficult to adapt the programs to other microprocessors to take advantage of a rapidly improving technology.     

A strategy for microcomputer-controlled measurement of responses in the behavioral laboratory

Problems associated with microcomputer measurement of responses in operant conditioning experiments are discussed. A general strategy that addresses these problems is presented. Although implementation of the strategy requires assembly language programming, the procedures can be used in conjunction with most high-level programming languages. The method ensures that all responses are detected, prevents detection of multiple responses during switch contact bounce, and indicates when responses are being processed at excessive intervals following their occurrences.     

A microprocessor-based psychopathology laboratory: III. Hardware

The hardware configuration of a psychopathology research and clinical laboratory is described. Design prerequisites that guided hardware selection include: flexibility in experimental control, ease of data handling, system mobility, operational simplicity, and a method of providing clinical feedback. The microcomputer, mass storage, digital input/output, timers, and the auditory and visual modes of interacting with subjects/patients are described. Component costs are illustrated.     

A microcomputer-controlled solid-state dark adaptometer

A low-cost microprocessor-controlled light-emitting diode (LED) dark adaptometer is described. The apparent intensities of red and green stimuli are controlled by changing the duty cycles of LED display elements which are operated at constant pulse repetition rates. The psychophysical method of limits is used to obtain threshold data. Stimulus parameters and test procedures are under software control. The design utilizes programmable integrated circuitry that may be used with a variety of microprocessors.     

A microcomputer-controlled complex reaction time instrument

An inexpensive microcomputer system that measures complex reaction time to a visual stimulus is described. This system can determine the rate of gain of information by utilizing a two-, four-, or eight-choice reaction time task encompassed within the same unit. The system turns on randomly chosen lights and monitors the time required for the subject to depress a corresponding switch. Information describing the stimulus and the subject’s response are printed on a Teletype after each response.     

A Winchester hard-disk integrated computer-assisted instructional laboratory: Hardware and data management considerations

The hardware configuration at the University of Kentucky is discussed with emphasis on a Winchester technology hard disk as the integrating feature. Advantages and disadvantages of this configuration are discussed in light of the issues of software transportability, ease of use for students, and system maintenance. The Winchester disk is compared to floppy drives as a means of program and data storage. The importance of proper, clear, and organized documentation is stressed. The conclusion is that each system can complement the other in a functional computer learning laboratory.     

A microcomputer-controlled system for measuring reactivity in small animals

A microcomputer-controlled system has been designed for measuring reactivity in small laboratory animals. This system uses a microcomputer to trigger an acoustic signal, which is fed to a loudspeaker through an audio power amplifier. An animal’s acoustic startle response is recorded using a moving-coil loudspeaker as a movement transducer. The transducer output is coupled to a peak-hold circuit that records the maximum voltage generated by the animal’s response. After conversion to digital form, the data for each stimulus presentation are stored and then printed when all trials have been completed.     

Measurement of activity in small animals using a microcomputer-controlled system

A computer-controlled system that detects spontaneous activity (locomotion and rearing) and diurnal activity rhythms in small animals is described. Automatic recording of subtotals during test periods provides data about habituation (nonassociative learning). The system is relatively inexpensive to construct. Fabricated from highly reliable circuit components, it provides replicable measures that enable comparisons between different experimental treatments to be made using parametric statistics.     

A microcomputer-based laboratory: Real-world experience

This paper discusses current hardware and software in use at the Center for Automated Systems in Education, a project of the department of psychology at Southwest Texas State University. The hardware ranges from inexpensive microcomputers to sophisticated color graphic display systems. The advantages and disadvantages of various systems are considered. Current projects of interest to educators and psychologists are mentioned.     

The measurement of differential thresholds for lifted weights by microcomputer-controlled apparatus

The measurement of differential thresholds (DLs) for lifted weights normally involves lengthy test sessions. This is due partly to the statistical techniques for measuring the threshold and partly to the methods adopted to present the stimuli. Attempts to speed up test procedures tend to produce unreliable DL estimates, or to measure the sense of force or effort rather than weight perception. To facilitate the measurement of DLs for lifted weights, an Apple microcomputer was programmed to generate Wetherill tracking procedures and was interfaced with two stimulus bearing turntables. Various lifting methods are easily implemented, and DLs are reliably and quickly measured. The adaptation of the apparatus for general use in investigating the haptic sense modality is discussed.     

Symposium: Hardware innovation and utilization

A tutorially structured symposium is being presented by professionals in various fields of computer technology. The symposium develops the theme of effective utilization of computer-related hardware in papers describing (a) elementary hardware logic design, (b) microcomputer and microcontroller design and applications, and (c) microprogramming techniques and applications.     

A mobile research laboratory

A .75-ton van was modified to make a mobile research laboratory suitable for visual psychophysical testing under well controlled conditions. The laboratory can be adapted easily to other types of psychological research in which environmental control and/or special-purpose equipment is required.     

A microprocessor-based real-time BASIC laboratory: A pulse motor-controlled visual stimulator

Using the Commodore PET as a random pulse generator, an inexpensive visual stimulator for psychophysical experiments can easily be made at low cost. The PIA interface that connects the external experimental devices is easily accessed by PEEKing and POKEing its registers with BASIC. Using pulse motors, two independent stimulator wheels, having 24 different color filters and a 2.4 log (.1 log unit steps) unit range light attenuator, are controlled by a randomized string of pulses via a PIA port, and the responses of the observer as well as the stimulus parameters are automatically written onto the cassette memory for further data analysis.     

Traditional minicomputers: A continuing role in the laboratory

The traditional laboratory minicomputer was programmed in assembler, in a home-built language, or in a fast, compiled language with access to assembler-coded subroutines. This software strategy remains useful on inexpensive, microcomputer-based hardware for many applications in which the computer must respond to external events within a few milliseconds. The benefits of rapid response and sometimes lower hardware expense may require the cost of increased software development complexity and time.     

A microprocessor-based psychopathology laboratory: IV. Software design

Software designed for the microprocessor-based psychopathology laboratory provides a powerful data collection and maintenance package. A library of prepackaged well-documented program modules has been developed to aid in developing and maintaining programs to administer experiments, to store, retrieve, and interpret data. A simple, but powerful, data base system allows new experiments to be incorporated easily, and obsolete experiments to be deleted. The data collection programs are independent of the general data base, permitting them to be moved to dedicated remote systems as necessary. The data are stored in raw form to permit the researcher to try novel approaches in interpreting existing data.