Ruler vs. the Apple II/FIRST system analysis of analog signals in classical conditioning

In our judgment, the Apple II/FIRST system (Scandrett & Gormezano, 1980) is an efficient and versatile system for experimental control and data acquisition in classical conditioning experiments. However, these attributes would be of limited value if the system did not extract measures from our analog signals with a high degree of correspondence with our ruler measurement procedures. Accordingly, we determined the system’s validity in extracting measures of CR occurrence and CR latency in three conditioning experiments. Pearson productmoment correlation coefficients indicated a very satisfactory degree of agreement on measurements made by the Apple II/FIRST system and ruler. Moreover, intraclass correlations and analysis of variance procedures applied to percent CRs and CR latency revealed several small, but divergent, differences between ruler and computer measurement of CR latency across the three experiments. However, subsequent analyses of variance revealed that the number and pattern of significant sources of variation for ruler or computer measurements were virtually identical. Accordingly, we have concluded that our system can successfully replace our traditional method of ruler measurement.     

Input protection for the laboratory computer

Circuit details are given for building protective interfaces between laboratory instruments and a computer’s analog and digital inputs. The protective interfaces will not only protect the computer and its input interfaces from a misconnection, but they will themselves withstand misconnection with no damage.     

Microprocessor control and A/D data acquisition in classical conditioning

An Apple II/FIRST system has been developed to control classical conditioning experiments, collect analog data, and to extract dependent variable measures of conditioning. With our selection of the Apple II microprocessor and an added hardware floating-point processor, we have been able to establish independent computer systems for each of our three conditioning laboratories at a fraction of the cost of our DEC PDP-8/e (which was interfaced to only one of our laboratories). Moreover, our software system, FIRST, an interactive, high-level, dictionary-based language, is a programming and control system whose flexibility and ease of programming far exceeds that experienced with our DEC PDP-8/e system (Millenson, Kehoe, Tait, á Gormezano, 1973; Tait & Gormezano, 1974). In our judgment, the Apple II/FIRST system is of unprecedented efficiency and versatility for the control, data acquisition, and data analysis of analog responses in classical conditioning experiments.     

COMPUTERS

Abstract: I offer an explication of the notion of computer, grounded in the practices of computability theorists and computer scientists. I begin by explaining what distinguishes computers from calculators. Then, I offer a systematic taxonomy of kinds of computer, including hard-wired versus programmable, general-purpose versus special-purpose, analog versus digital, and serial versus parallel, giving explicit criteria for each kind. My account is mechanistic: which class a system belongs in, and which functions are computable by which system, depends on the system's mechanistic properties. Finally, I briefly illustrate how my account sheds light on some issues in the history and philosophy of computing as well as the philosophy of mind.     

Experimental control and data acquisition with BASIC in the Apple computer

Laboratory experiments can be precisely controlled and data can be collected using the BASIC language on an Apple II+ computer with 48-KB RAM, disk drive, and two timer-I/O cards. The Apple BASIC makes machine language output control routines necessary, but quite convenient. By compiling BASIC, 50–100 inputs/sec are handled. Applications range from operant research and analog data collection to use of the Apple color display capability for stimulus presentations and response recording.     

A minicomputer program for control and data acquisition in classical conditioning

A 4K PDP-8/E computer program package has been developed to control classical conditioning procedures, to collect response data, and to extract statistical summeries. In contrast with other existing behavioral control languages geared to digital data typical of discrete operant analyses, this program distinguishes itself by its ability to retrieve and analyze the analog data arising from phasic response systems such as the rabbit’s nictitating membrane. By means of a question-and-answer Teletype conversation with the E, the program establishes trial sequence and trial spacing parameters; CS and US duration, probability, and interstimulus interval; intertrial interval fractionation for recording intertrial response frequencies; and session length. Various versions of the program exist to compute statistical properties of the analog response data, to dump detailed trial-by-trial topographies, and to attach instrumental contingencies to subtle features of the real-time analog responding.     

A general-purpose computer system for behavioral conditioning and neural recording experiments

A computer system designed to control the delivery of stimuli and data acquisition during behavioral conditioning and neural recording experiments is described. This IBM-PC-compatible system is programmed in C++ and is capable of controlling stimulus presentations to four independently operating conditioning chambers while collecting one channel of analog and two channels of digital data from each of the chambers. This system is currently being used in a variety of learning and memory experiments involving rats, rabbits, and humans.     

An inexpensive 1-millisecond experiment control interface for IBM PCs and its user-friendly control language

An inexpensive, professionally manufactured, digital I/O experiment control interface for any PC-compatible computer is described. It plugs into a standard printer port and provides 1-msec accuracy for up to 4 inputs and 22 outputs. It also allows experiment control procedures to be written in an easy-to-learn, easy-to-use Experiment Control language (ECBASIC). In addition to many instructions specifically designed to simplify behavioral research, ECBASIC provides for transparent collection and storage of event logs.     

Digital filtering and signal processing

The design, realization, and some of the many uses of digital filters are reviewed. Computer programs coded in FORTRAN are presented for the design of lumped parameter digital and analog filter systems which are simulated on a digital computer. Explanations of the programs are accompanied by examples of their use. There is a discussion of problems arising from errors of roundoff and approximation.     

Autoranging amplifier expands computer’s A/D sensitivity by two decades

This device accepts an analog signal from 0 to +14 V, automatically changes gain to condition the analog output to the limits of a ±1 V A/D converter, and transmits the gain mode as two digital bits. A computer with a 10-bit A/D converter and two sense lines uses this device to obtain the dynamic range of a 16-bit A/D converter. The relatively simple principle of the circuit may be of interest to expand the voltage sensitivity range of other analog devices for slowly changing signals.     

A study of sequential blanking and overprinting combined

By presenting alphabetic and other types of input characters, in either adjacent spatial locations or in the same spatial location, on the face of a cathode-ray tube (CRT) interfaced to a digital computer and by varying in systematic ways the interstimulus intervals (ISIsj and display orders of the several sequentially presented inputs, there has evolved what we call a “blanking-overprinting” paradigm. The use of such a paradigm has disclosed that the visual system can operate in a very sensitive and highly selective manner, “clearing” the first of two overprinted inputs that are separated in time by as little as 50 usec, while selectively inhibiting the second of these two overprinted inputs, if appropriate blanking inputs are present.     

A digital noise and sine-wave generator

A circuit is described that will digitally generate three kinds of signal useful in auditory research: broad-band pseudorandom noise, low-pass-filtered Gaussian noise, and low-distortion sine waves. This digital circuit has two advantages over its analog counterparts, ease of calibration and adaptation to computer control.     

Enhancing Digital Fluency through a Training Program for Creative Problem Solving Using Computer Programming

The purpose of this paper is to propose a training program for creative problem solving based on computer programming. The proposed program will encourage students to solve real‐life problems through a creative thinking spiral related to cognitive skills with computer programming. With the goal of enhancing digital fluency through this proposed training program, we investigated its effects. Two sets of experiments were performed in which 119 typical students and 30 younger, gifted students participated. Two synthetic creative problem solving tests, which had a high correlation with logical ability, scientific problem solving ability and divergent thinking ability, were developed to measure creative problem solving ability. We provided the treatment group with a paper‐based booklet with relevant problems developed specifically for that group. ANCOVA statistical procedures were used to analyze the pre‐ and post‐synthetic creative problem solving tests. The findings of our study are as follows: with typical students, the originality of the treatment group outperformed the control group, a result that was compatible with previous research. With gifted students, the fluency of the treatment group outperformed the control group, and overall creative problem solving ability was enhanced. Remarkably, fluency increased significantly, a notable difference from the results of prior studies. In conclusion, we inferred that, given the definition of digital fluency, if creative problem solving ability is enhanced by a training program for creative problem solving based on computer programming, digital fluency will ultimately be improved. In this paper, we discuss the result of fluency enhancement that contradicts prior research. We suggest that this training program could be a new learning environment for the students who have grown up with digital media.     

EyeRIS: A general-purpose system for eye-movement-contingent display control

In experimental studies of visual performance, the need often emerges to modify the stimulus according to the eye movements performed by the subject. The eye-movement-contingent display (EMCD) methodology enables accurate control of the position and motion of the stimulus on the retina. EMCD procedures have been used successfully in many areas of vision science, including studies of visual attention or eye movements and physiological characterization of neuronal response properties. Unfortunately, the difficulty of real-time programming and the unavailability of flexible and economical systems that can be easily adapted to the diversity of experimental needs and laboratory setups have prevented the widespread use of EMCD control. This article describes EyeRIS, a general-purpose system for performing EMCD experiments on a Windows computer. Based on a digital signal processor with analog and digital interfaces, this integrated hardware and software system is responsible for sampling and processing oculomotor signals and subject responses and for modifying the stimulus displayed on a CRT according to a gaze-contingent procedure specified by the experimenter. EyeRIS is designed to update the stimulus with a delay of only 10 msec. To thoroughly evaluate EyeRIS's performance, this study was designed to (1) examine the response of the system in a number of EMCD procedures and computational benchmarking tests; (2) compare the accuracy of implementation of one particular EMCD procedure, retinal stabilization, with that produced by a standard tool used for this task; and (3) examine EyeRIS's performance in one of the many EMCD procedures that cannot be executed by means of any other currently available device.     

Generating complex waveforms

A wide variety of complex waveforms can be generated by approximating the desired analog waveform from an array of digital values. Some basic properties of these digital approximations are discussed in terms of pulse amplitude modulation and sampling theory. The waveforms are generated by transferring the digital values to a digital-to-analog converter followed by a low-pass filter. This usually requires the dedicated use of a computer. We have built a device, incorporating solid state memory, that can store, time, and transfer previously computed digital values, so that a computer is no longer necessary to generate the waveforms. Specifications of the digital-to-analog converter and appropriate settings of the filter are discussed, along with a simplified procedure for calculating waveforms that have line spectra. An adaptation of this procedure enables the device to be used as a high-speed programmable pure-tone source.     

Use of on-line computers in experimental psychology: Hardware considerations

A series of modules provide students with the basic skills to set up and use a computer to run psychological experiments. The modules include basic knowledge of AC/DC power supplies, relay switching, analog/digital conversion, integrated circuit board design and soldering, and elementary programming (FORTH and BASIC). These skills are then utilized to build an interface board and to design and run actual on-line experiments. The hardware orientation is combined with computer skills and experimental methodology to allow students to experience all stages of modem psychological experimentation.     

A virtual reality scenario for all seasons: the virtual classroom

Treatment and rehabilitation of the cognitive, psychological, and motor sequelae of central nervous system dysfunction often relies on assessment instruments to inform diagnosis and to track changes in clinical status. Typically, these assessments employ paper-and-pencil psychometrics, hands-on analog/computer tests, and rating of behavior within the context of real-world functional environments. Virtual reality offers the option to produce and distribute identical "standard" simulation environments in which performance can be measured and rehabilitated. Within such digital scenarios, normative data can be accumulated for performance comparisons needed for assessment/diagnosis and for treatment/rehabilitation purposes. In this manner, reusable archetypic virtual environments constructed for one purpose can also be applied for applications addressing other clinical targets. This article will provide a review of such a retooling approach using a virtual classroom simulation that was originally developed as a controlled stimulus environment in which attention processes could be systematically assessed in children with attention-deficit/hyperactivity disorder. This system is now being applied to other clinical targets including the development of tests that address other cognitive functions, eye movement under distraction conditions, social anxiety disorder, and the creation of an earthquake safety training application for children with developmental and learning disabilities.     

Analog and digital,continuous and discrete

Representation is central to contemporary theories regarding the mind/brain. But the nature of representation—both in the mind/brain and more generally—is a source of ongoing controversy. One way of categorizing representational types is to distinguish between the analog and the digital: the received view is that analog representations vary smoothly, while digital representations vary in a step-wise manner. In other words, ‘digital’ is synonymous with ‘discrete’, while ‘analog’ is synonymous with ‘continuous’. I argue that this characterization is inadequate to account for the ways in which representation is (and should be) used in cognitive science; in its place, I suggest an alternative taxonomy. I will defend and extend David Lewis’s account of analog and digital representation, distinguishing analog from continuous representation, as well as digital from discrete representation. I will argue that the distinctions available in this fourfold account better accord with representational features of interest in cognitive science than the received analog/digital dichotomy.     

A 6809 single-board computer system for the control of behavioral experiments

A computer system consisting of a 6809 single-board computer in conjunction with an IBM-compatible Personal Computer (PC) is described for the control of behavioral experiments. The single-board computer uses the C programming language to program experimental events. Each component of the system (the single-board computer, a digital interface, the PC, and the software) is outlined with its capabilities and drawbacks noted.     

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.