A microcomputer-based cardiotachometer with video display

A KIM-1 single board microcomputer implementation of a cardiotachometer that provides a low-cost versatile heart-rate data acquisition system is described. Unique features include telemetry, a composite video output signal of a video frame displaying elapsed time and heart-rate, and a TV camera signal of the behavior. Data is videotape- and/or audiotape-recorded for further analysis with a larger computer.     

A computer-controlled vapor-dilution olfactometer

A computer-controlled olfactometer with several innovations leading to closer control over the stimulus parameters and minimization of nonolfactory cues is presented. A microcomputer is used to control the stimulus duration and interstimulus interval. Electronic mass flow con-trollers are employed to maintain close control over the flow in the pure air line and the stimulus-bearing line. Both humidity and temperature are closely regulated. Using a nasal catheter, this stimulus delivery system coupled with velopharyngeal closure and oral breathing permits accurate specification of the quantity of stimulus material actually entering a subject’s nares. The design is such that the computer programming, patch panel interface, and threaded tubing allow versatility in the type of olfactometric study that can be conducted. This system is amenable for threshold, electrophysiological, and sensory adaptation studies of olfaction.     

A flexible computer-controlled perception laboratory

Research in perception is often guided or limited by the capabilities of the laboratory. A computer-controlled perception laboratory is described that was designed to be extremely flexible at a modest cost. The laboratory permits control of onset time, offset time, and intensity of visual, auditory, and tactile stimuli. The visual stimuli include single points, text, stereoscopic displays, and two-dimensional representations of three-dimensional objects moving in space. The design of the hardware and software and the criteria that guided our choice of this design are discussed. Finally, potential applications of this laboratory are considered.     

A two-dimensional computer-controlled visual stimulator

A computer-controlled instrument that creates complex two-dimensional patterns on a CRT monitor is described. These patterns are used to elicit visual evoked responses. Patterns are produced on a raster that is rotatable about its center. It is possible to assign to arbitrary regions in the raster any of four independent one-dimensional spatial-temporal functions. For each spatial-temporal function, the experimenter can select an arbitrary spatial profile, the spatial frequency of the profile, the starting phase of the profile, the temporal function, and the depth of modulation.     

A simple inexpensive computer-controlled tone generator

A simple circuit for a keyed tone generator is described. The total construction cost is less than $5. Various adaptations and modifications of the circuit are discussed.     

A computer-controlled system for training and testing primates

The hardware and software for a computer-controlled training and testing system for primates are described. The computer (DDP-116 in the Computer-Controlled Psychology Laboratory at Carnegie-Mellon University) controls all stimulus presentation, reinforcement, and records data in a form ready for analysis on a larger computer.     

FOCLAB: A language for computer-controlled psychology research

The FOCLAB system, a dialect of FOCAL, provides complete real-time experiment control and data acquisition capabilities in the area of experimental psychology. The language provides digital and analog input/output, graphics (including alphanumerics) on a refresh CRT, and a powerful set of time measurement operations. With these facilities FOCAL may be used in cognitive and operant, as well as psychophysiological research. FOCLAB will operate with either PDP-8 or PDP-12 systems, and can control most of the currently existing lab interface options for these computers. The system will operate on 8K core-only machines, as well as under OS/8.     

A computer-controlled laboratory for studying infant event perception

An integrated software package for testing infants in a habituation procedure is described. The software is written for an Apple II computer with a minimum of 64K of memory. Additional interface cards are required for timing responses and displaying dynamic stimuli. The software is divided into four independent modules: (1) Configure Experiment allows the experimenter to design a specific experiment. (2) Run Experiment controls the running of a previously configured habituation experiment. (3) Calculate Reliability allows a second observer to score the subject for the purpose of computing reliability. (4) Data Summary and Formatting provides a summary of the results and allows the user to flexibly format the data for reading by various statistical packages.     

Painless computer-controlled experimentation

More Es might employ computers to control psychological experiments if computer languages suitable for experimental control were easier to learn. In fact, course author languages intended for writing instructional sequences offer many facilities desirable for experimental control. A particular language, CAN-4, is examined for its suitability, and its use in a concept learning experiment is illustrated.     

A computer-controlled administration of the matching familiar figures test

The Kagan Matching Familiar Figures Test of Impulsivity/Reflectivity was modified to allow computer control of stimulus presentation and data acquisition via IBM-compatible systems. The comparability of computer administration and traditional hand administration was examined in a split-half study with a sample of 58 students (ages, 18–39 years). Analyses of variance revealed no significant differences between the administration techniques for latency and a small but significant difference for accuracy. Correlations between the two administration techniques were .61 for latency and .40 for error scores. Internal consistency coefficients for computer administration exceeded those for hand administration on both latency and accuracy. These data compare favorably with results reported by others and suggest that computer administration offers a viable alternative to traditional hand administration of the MFFT in research applications.     

APCOL: A programming system for computer-controlled psychology laboratories

The development of on-line computer systems can be facilitated by higher-level programming languages that are more powerful and easier to learn than machine-level Assembly languages. In general, it is not possible to speak ofa programming language without also describing the operating system and functional problem domain of the small computer system for which it is intended. This is because of the great variety in the architecture and configuration of small computers. However, it is possible to state more general requirements and design criteria for on-line computer languages in psychology. APCOL is an example of an integrated programming system. One of the important distinguishing features of the system is that it is implemented both on the small-scale laboratory computer and on a large general-purpose computer linked to the smaller machine via a high-speed communications network. This arrangement permits firsthand access to interactive program construction with immediate test of program function by using the on-line implementation as well as access to the text-editing and mass storage facilities of the large-scale machine.     

A computer-controlled electrogustometer for the estimation of evoked taste thresholds

Reliable taste detection thresholds in humans are difficult to obtain for either research or clinical purposes because ordinary taste stimuli cannot be generated and presented by means of a computer. However, in investigations of taste dysfunction, electrical taste stimulation (electrogustometry) is sometimes employed. Minute anodal direct currents are applied manually to the tongue, giving rise to an acid taste experience through the liberation of protons into the saliva. This experience accords with recent findings on the mechanisms underlying sour taste perception. The device described here is a safe and accurate constant-current device, operating under computer control at very low amperages, making it possible to apply modern psychophysical procedures to the measurement of evoked taste thresholds.     

A computer-controlled olfactometer for fMRI and electrophysiological studies of olfaction

A design for an inexpensive and reliable olfactometer is presented. The design has several advantages for fMRI and electrophysiology investigators. These advantages include relatively rapid odorant rise times, computer control, multiple odor administration, and no ferrous materials near the subjects. In addition, the device is contamination resistant, and, because the air is neither warmed nor humidified, it is unlikely to become an incubator for bacteria. The olfactometer is constructed of off-the-shelf chromatography parts that require little modification.     

An eight-channel computer-controlled scanning electromyograph

A measurement system is described for the computerized detection, digitizing, and storage of electromyographic (EMG) signals from up to eight muscle groups. The use of a channel scanning technique allows almost simultaneous multichannel recording with minimal circuit redundancy. Specifically, the scanning electromyograph allows several EMG preamplifiers to share expensive isolation, signal-conditioning, and interface circuitry. The design incorporates monolithic integrated circuit preamplifiers and includes optical isolation of the preamplifier circuitry for protection of the subject. Hybrid active filter modules allow convenient selection of system bandpass characteristics. Key measurement parameters are software programmable. The scanning electromyograph is inexpensively constructed from readily available componentry. Specifications for all functional blocks within the instrument are comparable to those of commercial instrumentation.     

A low-cost computer-controlled function generator suitable for generating visual grating displays

This paper reports a simple low-cost computer peripheral for generation of gratings. Its advantages are minimal CPU operations, reliability, and variety of programmable output functions.     

High-speed point plotting with computer-controlled displays

A method is described for the high-speed plotting of many independently generated elements in a computer-controlled display.     

On timing events in computer-controlled experiments

This paper considers the problem of timing events in computer-controlled experiments. A digital clock is defined as a time-mark generator or “ticker” and a counter. A discussion of time-mark generators commonly used in computers is followed by a consideration of several ways in which computer clocks are implemented and used. A framework for the latter discussion is provided by a classification of clocks in terms of whether the ticker or the counter (either or both) is internal or external to the computer.     

A modular,computer-controlled system for olfactory stimulation in the MRI environment

Although the cerebral networks involved in sensory perception are of general interest in neuroscience, registration of the effects of olfactory stimulation, especially in a magnetic resonance imaging (MRI) environment, presents particular problems and constraints. This article presents details of a reliable and portable system for olfactory stimulation that is modular in design and based on microcontroller technology. It has the following characteristics: (1)?It is under software control; (2)?the presentation of olfactory stimulation can be synchronized with respiration; (3)?it can be manually controlled; and (4)?it is fully compatible with an MRI environment. The principle underlying this system is to direct an odor to the subject’s nostrils by switching airflow to different odor diffusers. The characteristics of this system were established using (1)?ultraviolet (UV) spectroscopy, to measure its response time, and (2)?gas chromatography, to measure the repeatability of odor presentation in terms of gas concentration. A response time of 200?± 25 ms was obtained for the system, and the standard deviations of the gas concentration delivered during stimulation ranged from 1.5% to 22%, depending on the odor, the airflow, and the dilution of the odor used. Since it is portable, controlled by software, and reliable, on the basis of the results we obtained, this system will lend itself to a wide range of applications in olfactory neuroscience.     

Seven types of data from computer-controlled experiments

Seven types of data often need to be accessed from a computer-controlled experiment. Some of them involve only a single word and must be available within a fraction of a second; others may involve hundreds of thousands of words, but need not be available until a few hours after an experimental session. A time-sharing program for on-line control of psychological experiments should have the facilities for dealing with all seven types of data.