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At least 469 records · Page 26Linked to original sources

An adaptable microcomputer program for recording behavior durations.

A versatile and easy to use program is described for monitoring and recording behavior durations on IBM-compatible microcomputers. The program also records frequencies and provides latency information. Among its more prominent attributes are its ability to accommodate a broad range of behavioral assays and the facility with which its operation can be mastered. It requires no specialized hardware and is capable of being used in conjunction with a number of commercially available software packages for statistical analysis.

Animals↗

An adaptable microcomputer program for monitoring behavior.

We describe an improvement of a flexible and easy to use program for monitoring and recording behavior durations with IBM-compatible microcomputers and a companion program that provides additional versatility for handling data. Up to 35 behaviors or events can be monitored, and processing speed is fast enough to measure even very rapidly performed behaviors. No specialized hardware is required, and the data files that are created are compatible with commercially available software packages for statistical analysis.

Animals↗

A microcomputer-controlled demand feeder for the study of feeding behavior in fish.

This paper describes an easy-to-make, low-cost demand feeder. The electromechanical design ensures a single-pellet delivery for each demand. The feeder, activated by a fish pressing a bar, is driven by a solenoid. A variety of pellet shapes and sizes can be used, offering broad experimental versatility. The feeder is also suitable for microcomputer control.

Animals↗

Accurate control of contrast on microcomputer displays.

Off-the-shelf microcomputers can now display arbitrary 8-bit images, but accurate control of these images requires dealing with several undesirable properties of real digital to analog converters (DACs) and analog video monitors. The limitations of DACs and video monitors are presented in the form of a model for their calibration and use in vision experiments. Low contrasts can be accurately rendered by summing a small accurate a.c. signal and a large less-accurate d.c. signal (Watson et al., 1986; Behavior Research, Method, Instrument and Computers, 18, 587-594). Exploiting that idea, this note presents an easy-to-build passive resistor network, a video attenuator, that combines the outputs of three 8-bit DACs to render low contrasts with 12-bit accuracy at the display. Measurements confirm the 12-bit accuracy.

Analog-Digital Conversion↗

A microcomputer method for behavioral data acquisition and subsequent analysis.

Using a microcomputer (TRS80, Model III), a modular procedure is described which allows rapid manual encoding of visually-observed behavioural units (module 1); processing of the data (e.g., calculation of frequency, duration, latency, sequence analysis) (module 2) and statistical analysis (module 3). This method can be used in several behavioural tasks and provides the possibility of various subsequent analysis without re-encoding or transcribing the initial data.

Animals↗

Microcomputer adaptation of the wheel-shaped activity monitor: effects of lindane.

The development of microcomputers with increased power and memory capacity may allow for the spreading of the techniques of microanalysis of animal behavior in neurotoxicology. The present work describes the adaptation of the wheel-shaped activity monitor to a personal computer system (IBM-PC/XT/AT-compatible). The system has been used to study the effects elicited by a single 30 mg/kg dose of the organochlorine insecticide gamma-hexachlorocyclohexane (lindane) on the spontaneous behavior of rats. Lindane induced complex changes in behavior, the most prominent being a disruption of the temporal pattern of activity and changes in the local activity/locomotor activity ratios and in place preferences in the monitor. Effects on body weight and number of fecal boluses were also observed.

Animals↗

Adaptive microcomputer control of an artificial knee in level walking.

An experimental microcomputer controlled prosthesis is discussed, where knee damping is governed by kinematic signals, picked up from both legs. The control algorithm is based on division of the walking cycle into ten stages; each stage characterized by an appropriate damping level which governs the restraining moment at the knee, as functionally required. Stage identification is carried out by the kinematic inputs. The experimental prosthesis was tested on one amputee, the first author of this paper. The control system was found to be more advantageous than a conventional valve system in significantly reducing hip muscular effort on the prosthetic side. Gait symmetry is also improved.

Computers↗

A microcomputer-based binaural measurement system.

A microcomputer is used to control a dual-channel, sine-wave generator as the excitation to both the left and right ears in experimental subjects, and for on-line measurement of the neuronal spike counts. The effects of varying the walking pattern and phase angle between the two channels can be investigated. After normalisation of spike counts, the result can be displayed as a 3-D plot on a CRT or an x-y plotter. The system is useful for general steady state and transient binaural measurement.

Biomedical Engineering↗

Analysis of saccadic eye movements with a microcomputer.

This analysis of saccadic eye movements has found use in clinical diagnosis. Saccades are induced by a microcomputer-controlled TV stimulator and are recorded by electro-oculography. The analysis algorithm detects saccades by the velocity profile of eye position and then computes the principal saccadic parameters, peak velocity and amplitude. In addition, the saccades are presented on the VDU screen, together with the computed results of the analysis; they may be edited if necessary. The programs have been implemented in Pascal and Assembler languages.

Computers↗

Measurement of the temporal and spatial parameters of gait using a microcomputer based system.

This paper describes a system for measuring the temporal and spatial parameters of gait. The basis of the system is a resistive grid walkway which is controlled by a microcomputer which also collects, processes and stores the data from the walkway. The data obtained from the system, including the temporal and spatial parameters of gait such as step and stride lengths, the durations of swing and support phases of the gait cycle and walking speed, are presented in both numerical and graphical forms. Accuracy to within 1 cm has been verified by analysing videotapes of foot placement during a walk. Special emphasis has been placed on making the system software user-friendly. The presentation of date uses several types of display, from a simple graphical summary of the walk statistics to a more complete report showing all the data from each stride. In the year during which the walkway system has been operational, it has been found easy to use by both subjects and operators, and it produces very useful data.

Biomedical Engineering↗

Dimensional measurements on images from a video camera or cassette recorder using a BBC microcomputer.

We have developed a system that enables a BBC microcomputer to make dimensional measurements on images from a video camera or cassette recorder without a framestore. The RGB output of the computer is synchronized to the output of the camera or recorder and the two displayed simultaneously on the same monitor. Measurements can be made directly from the displayed image using points indicated by the computer graphics cursor via its keyboard. Distances can be measured with a precision of about 0.4%. The system is very versatile but is especially useful for measuring the freeze-frame output from a Philips standard videotape.

Computers↗

A microcomputer-based video vector system for clinical gait analysis.

A microcomputer-based video vector system has been developed to display the resultant ground reaction force vector on a television image of the subject in real-time. For each television field the force platform signals are acquired and processed and the resultant force vector superimposed on the video image of the walking subject. The force platform results are stored on disc and the composite video signals recorded on video tape for further analysis. The system is easy to set up and use and the results can be readily interpreted. The external moments produced at the joint centers by the ground reaction forces can be observed visually and, if required, quantification of the external moments can be achieved following data collection. The spatial resolution of the system is 0.342% vertically and 0.156% horizontally. The force vector visualization technique has routine applications in orthotics and prosthetics. It is also a useful technique for the teaching of biomechanics.

Calibration↗

A microcomputer-based drop counter.

A microcomputer-based drop counter is described that allows the accurate measurement of fluid flows up to about 5 ml/min. Detailed construction information is included. Unlike most previously described drop counters, it displays flow directly in ml/min and calculates a confidence limit for the measurement.

Blood Flow Velocity↗

A simple microcomputer-controlled device for automated measurement of refractory period of excitable tissue.

A computer-controlled tissue stimulator interface will be described. This device can generate a basic train at a predetermined rate. An extra pulse is introduced after a selected number of pulses. The initial latency of this extra pulse is shorter than the tissue refractory period. The latency is increased, automatically, until the tissue produces a conducted response. This is made possible by the computer checking the tissue response. The device is inexpensive and can be readily controlled by any 8 bit microcomputer, such as the Commodore PET or VIC-20. The use of a signal conditioner has been discussed. Such a circuit facilitates detection of the often slowly occurring action potential of the premature beat riding on the repolarization phase of the normal action potential.

Electronics↗

Microcomputer acquisition and analysis system for the isolated working heart preparation.

An automated data acquisition and analysis system based on a microcomputer (Apple II Plus) is described. The system was developed and used to collect and analyze data from rat working heart preparations. The system eases both data acquisition and calculation of derived parameters. Certain sources of error in these calculations are eliminated. The methods and formulae used to obtain various parameters of cardiac function are detailed. In addition, sample data are shown for the effect of thyroid hormone pretreatment on rate of left ventricular pressure development in the rat working heart.

Animals↗

Data acquisition and analysis of hemodynamic signals using a standard microcomputer.

Hemodynamic drug-effect studies require repetitive measurements and time-consuming calculations, particularly for the indices of left ventricular (LV) contractility and relaxation. To save time, we have created a system of acquisition, calculation, storage, and report of hemodynamic data processing E.K.G, peripheral arterial pressure, and LV pressure signals using a standard microcomputer (Apple II+) and simple accessory devices. The master program is written in BASIC Applesoft, with Mem/Dos as the disk operating system. A suite of utility routines, written in machine language, are used to program the A/D converter and to perform the vectorial calculations on the data. The software, written to process single-dose drug-effect studies, performs 1) data acquisition and storage as vectorial arrays accessible using BASIC, 2) monitor display, 3) calculations of the peripheral pressure and of the LV contractility and relaxation indices, 4) storage of the calculated indices, and 5) print-out of a report (curves and tables) at the end of each experiment and cumulated results of all the animals included in a protocol. The drawback of such a low-cost system is essentially the lack of available memory and the relatively slow speed of the microprocessor, which hinders simultaneous processing of indices needing nonlinear curve fitting and adequate print-out of protocols that are not single dose.

Animals↗

The use of a compact protable microcomputer system (EPSON HX 20) to measure on-line the contractile activity of the digestive tract from eight channels. Application to pharmacological tests.

The chronically prepared gut with strain-gauge transducers is a useful model to evaluate the effects of drugs affecting the digestive motility in fed and fasted animals. This paper describes a rapid and reproducible on-line microcomputerized technique to evaluate continuously, 23 hr per day, the level of gut motility using a portable compact microcomputer (EPSON HX 20). The gastric, intestinal, and colonic motility indexes were automatically determined from the surface of the contractile waves from eight different sites over periods of time varying from 1 to 120 min. This system has been successfully used to investigate the motor effects of spasmolytic or antidiarrheal drugs inravenously (N-butyl-hyoscine, trospium, secoverine, and prifinium) or orally (trimebutine, loperamide) administered in conscious, fed dogs.

Animals↗