A restraint system for the psychophysiological study of dogs

The present report describes a system for continuous psychophysiological study of the dog in a relatively flexible restraint harness that maintains the animal in a constant directional orientation, but allows him to assume any of a number of standing, sitting, or lying positions. The system permits the concurrent monitoring of behavioral and physiological processes under both acute and chronic conditions. A harness consisting of a leather collar and two body yokes is suspended from a pivoting metal hanger assembly. The harness is integrated with an isolation hamber equipped with automatic food, ater, stimulus, and response devices. Techniques for installing and maintaining dogs in the harness are described. A system for the continuous monitoring of cardiovascular functions and some experimental uses of the restraint system are suggested.     

A pseudorandom noise generator for use in auditory research

A noise generator that is capable of delivering long-duration samples of reproducible noise is described. The noise is generated as a pseudorandom telegraph waveform but may be filtered so that its amplitude distribution is approximately Gaussian. The design and construction of the generator are detailed and a few possible applications are given.     

A system for computer control of auditory stimuli

A computer system for generation of auditory stimuli is described. The system produces natural-speech or software-generated stimuli for monaural, binaural, or dichotic presentation. Stimuli have been generated for experiments run both on-line and off-line.     

A pointing technique for rapidly collecting localization responses in auditory research

A technique is described for rapidly collecting responses in auditory-localization experiments. Subjects indicate the perceived direction of the sound by pointing at a 20-cm-diam spherical model. In Experiment 1, the subjects judged the direction of a broadband signal, which could originate from any of 239 directions ranging through 360° of azimuth and between ?45° and +90° of elevation. Using this technique, the subjects responded 2–8 times more rapidly than previous subjects who used either a verbal-reporting technique or a head-pointing technique. Localization judgments were as accurate as they had been with verbal reports, but were not as accurate as judgments collected using the head-pointing technique. In Experiment 2, the signal was turned off and the experimenter read the spherical coordinates of the signal location to the subjects. The subjects pointed to these coordinates more accurately than they had judged the direction of the sounds in Experiment 1, suggesting that the response technique had not been the limiting factor in that experiment. Circumstances relevant to the choice of response techniques for auditory-localization experiments are discussed.     

A comparative review of the primate motor system

Primates have evolved separately from other mammals since the late Cretaceous, and during this time the two major extant primate groups, prosimians (lorises, lemurs, and tarsiers) and anthropoids (monkeys, apes, and humans) arose. Concurrently, structures within the central nervous system acquired primate characteristics. Not all of the uniquely primate features have been identified in the brain, but several are well known. The pyramidal system, the best studied motor system, shows a distinct primate pattern in its terminal connections in the spinal cord. Other descending systems are less well known, but primate specializations in the vestibular system and red nucleus have been observed. The primary and secondary motor cortices are topographically separated in primates, suggesting one basis for increased complexity. Given the size of the brain, structures in the basal ganglia are relatively enlarged in primates as compared with other mammals, whereas the cerebellum has the same relative size.     

A sample-to-disk system for psychomusical research

A hardware-and-software system is described that permits musical-bandwidth signal quantization, monophonic or stereophonic, direct to/from hard disk. The system, which uses an IBM AT or compatible, is cost effective and device independent. Software functions allow for automated aural and graphical signal analyses. Perceptual experiments that use contextual, natural-instrument stimuli, and that take advantage of the immediate and random access provided by this system, are described.     

Production and control of auditory signals in attention research using the Apple-Psych system

A technical issue in auditory spatial attention research is how best to provide low-cost, accurate control of the frequency, duration, and location of acoustic signals. Three solutions to the problem are compared: use of the internal oscillator of the Apple lIe, use of a Mountain A/D+D/A card, and use of an external oscillator chip. The unique advantages and drawbacks of each system are discussed. All share some common problems of external speaker interface, timing control, and interface with the software. Hardware and software solutions implemented on the Apple-Psych system are discussed, along with data that demonstrate the precision control achieved with the system.     

An automated system for primate instruction for behavioral neurophysiology

This paper describes a flexible hardware/software system developed for use with a PDP-8I computer for conducting research in behavioral neurophysiology. A real time monitor was designed to facilitate development, debugging, and modification of programs to run experiments. It relieves the programmer of the burden of dealing with hardware dependent functions such as interrupt handling and input/output. In addition, it provides the user with a large library of callable routines to perform functions commonly needed for conducting experiments. The monitor is modular in design and could be expanded or modified for use with many configurations of the PDP-8 family of computers.     

A CRT graphics system for experimental research

A graphics system to create, display, store, and print stimuli in a hardware-enhanced, microcomputer-driven CRT environment is described. This graphics system is compared with other computer-based systems, as well as with systems requiring the use of tachistoscopes.     

A proposal for handling missing data

A method for dealing with the problem of missing observations in multivariate data is developed and evaluated. The method uses a transformation of the principal components of the data to estimate missing entries. The properties of this method and four alternative methods are investigated by means of a Monte Carlo study of 42 computer-generated data matrices. The methods are compared with respect to their ability to predict correlation matrices as well as missing entries. The results indicate that whenever there exists modest intercorrelations among the variables (i.e., average off diagonal correlation above .2) the proposed method is at least as good as the best alternative (a regression method) while being considerably faster and simpler computationally. Models for determining the best alternative based upon easily calculated characteristics of the matrix are given. The generality of these models is demonstrated using the previously published results of Timm.     

Zoroaster: A multiprogramming system for psychological research

The development of a multiprogramming system for psychological research was undertaken on a PDP-9 computer with 8k memory. The needs of the users and the time demands on the computer raised several important questions: (1) Can a practical timesharing system be developed with only 8k memory? (2) Can critical timing functions be maintained? (3) Can easy access be provided (e.g., Fortran) to all experimental devices? (4) Can a system be designed which will take advantage of and be compatible with most of the standard DEC-provided software (e.g., Fortran compiler, loader)? The system was successfully developed by using a rapid within-core swapping technique, standard I/O routines, many general-purpose handlers and subroutines, and fully utilizing available core.     

A model system for psychotherapy research data management

An on-line data management system was developed to provide optimal access to research data. The specific application involved collecting data on four outcome measures from patients receiving brief psychotherapy to ameliorate a stress response syndrome. The on-line data management system also was designed to be transported to other research settings; a variety of other applications of this system are suggested. The need for such a system, the elements that it comprises, its operation, and its availability also are covered.