A portable four-channel cassette recording system for short-term electroencephalogram in the field

A portable four-channel electroencephalogram (EEG) cassette recording system has been designed which offers good performance, is simple to construct, and moderate in cost. The recorder is compatible with a commercially available, portable, battery-operated power source, and is therefore usable in the field where line power is unavailable. The system incorporates a small, lightweight, portable, battery-powered oscilloscope which provides monitoring and playback capability. While a few experimental portable EEG recorders have been reported in recent years with more channel capacity or perhaps lighter weight, the engineering details of these units are rarely published and, in any event, would require a substantial effort for most electronics support shops to reproduce. The recording system described here, however, should be within the capability of most electronics support groups to assemble in a very short time and provide good performance.     

On-line monitoring of eye-position signals in contingent and noncontingent paradigms

This paper presents a research methodology for the study of human attentional and perceptual processes by means of on-line monitoring of eye-position signals. The first part of the presentation considers techniques by which commercially available apparatus may be interfaced to a minicomputer for purposes of monitoring eye-position signals during psychological experiments. Hardware and software techniques related to automating the calibration, recording, and analysis of eye-position data are discussed. The second part of the paper discusses a more advanced research methodology, one in which visual stimuli are contingent upon momentary eye-position signals. The methodology is appropriate to a variety of studies in which eye movements are considered to be part of an attentional control system. Several experimental applications are described. The implementation of eye-position-stimulus contingencies on a small computer poses additional technical problems, several of which are discussed.     

A motor timing experiment implemented using a musical instrument digital interface (MIDI) approach

The musical instrument digital interface (MIDI) offers a way for perception and behavior researchers to implement high-quality experiments using inexpensive, commercially available hardware and software. We describe the MIDI and illustrate its applicability to research using a replication of the oscillator signature finding reported recently by Collyer, Broadbent, and Church (1992, 1994).     

Observation and analysis of large-scale human motion

Many team sports include complex human movement, which can be observed at different levels of detail. Some aspects of the athlete's motion can be studied in detail using commercially available high-speed, high-accuracy biomechanical measurement systems. However, due to their limitations, these devices are not appropriate for studying large-scale motion during a game (for example, the motion of a player running across the entire playing field). We describe an alternative approach to studying such large-scale motion, and present a video-based, computer-aided system, developed specifically for the purpose of acquiring large-scale motion data. The baseline of our approach consists of sacrificing much of the spatial accuracy and temporal resolution of widely used biomechanical measurement systems, to obtain data on human movement that span large areas and long intervals of time. Data can be obtained for each of the observed athletes with reasonable amount of operator work. The system was developed using the recordings of a handball match. Several field tests were performed to assess measurement error, including comparison to one of the widely available biomechanical measurement systems. With the help of the system presented, we could obtain position data for all 14 handball players on a 40 x 20 m large court with RMS error better than 0.6 m, covering 1 h of action. Several results, obtained during the handball match study are presented, in order to highlight the importance of large-scale motion acquisition.     

Why and how to use virtual reality to study human social interaction: The challenges of exploring a new research landscape

As virtual reality (VR) technology and systems become more commercially available and accessible, more and more psychologists are starting to integrate VR as part of their methods. This approach offers major advantages in experimental control, reproducibility, and ecological validity, but also has limitations and hidden pitfalls which may distract the novice user. This study aimed to guide the psychologist into the novel world of VR, reviewing available instrumentation and mapping the landscape of possible systems. We use examples of state-of-the-art research to describe challenges which research is now solving, including embodiment, uncanny valley, simulation sickness, presence, ethics, and experimental design. Finally, we propose that the biggest challenge for the field would be to build a fully interactive virtual human who can pass a VR Turing test – and that this could only be achieved if psychologists, VR technologists, and AI researchers work together.     

CAI-enhanced exam performance in a research design course

The efficacy of computer-assisted instruction (CAI) for increasing test performance in an experimental design course was tested using two commercially available programs to supplement course material. CAI was used to supplement course content for one of three examinations. Comparisons were also made with performance on the exams from 2 previous years. The results indicate a significant enhancement of performance by CAI.     

A computer-compatible multichannel event counting and digital recording system

An inexpensive multichannel event counting digital recording system has been designed for compatibility with automated data analysis equipment. For as many as 16 channels, events are simultaneously summed over preselected repetitive time intervals and recorded. Each data entry is marked with the time of day and a code identifying each channel’s data. The data is formated to be computer compatible and is logged on inexpensive readily available digital magnetic tape cassettes.     

EthoVision: A versatile video tracking system for automation of behavioral experiments

The need for automating behavioral observations and the evolution of systems developed for that purpose is outlined. Video tracking systems enable researchers to study behavior in a reliable and consistent way and over longer time periods than if they were using manual recording. To overcome limitations of currently available systems, we have designed EthoVision, an integrated system for automatic recording of activity, movement, and interactions of animals. The EthoVision software is presented, highlighting some key features that separate EthoVision from other systems: easy file management, independent variable definition, flexible arena and zone design, several methods of data acquisition allowing identification and tracking of multiple animals in multiple arenas, and tools for visualization of the tracks and calculation of a range of analysis parameters. A review of studies using EthoVision is presented, demonstrating the system’s use in a wide variety of applications. Possible future directions for development are discussed.     

Open courseware and shared knowledge in higher education

Most college and university campuses in the United States and much of the developed world today maintain one, two, or several learning management systems (LMSs), which are courseware products that provide students and faculty with Web-based tools to manage course-related applications. Since the mid-1990s, two predominant models of Web courseware management systems have emerged: commercial and noncommercial. Some of the commercial products available today were created in academia as noncommercial but have since become commercially encumbered. Other products remain noncommercial but are struggling to survive in a world of fierce commercial competition. This article argues for an ethics of pedagogy in higher education that would be based on the guiding assumptions of the non-proprietary, peer-to-peer, open-source software movement.     

A system for providing tactile EMG biofeedback

This report describes a flexible and inexpensive biofeedback system for providing discrete pulses against the skin surface at a frequency proportional to the level of activity from selected muscle groups. The primary components consist of a voltage controlled pulse generator and a tactile transducer. Other system capabilities include the production of digital information for recording devices and the providing of pulsed auditory EMG biofeedback. The system may be particularly applicable for the experimental reduction of psychological and muscle tension.     

PSYCHOL: A computer language for experimentation

Psychologists employing digital computers in the laboratory to control experimental procedure must construct programs. A language is described that incorporates many data representations and manipulations useful in presenting stimuli, collecting responses, and deciding the course of an experiment. PSYCHOL is an extension to a subset of ALGOL, with data types extended to include simple lists, strings of text, historic variables, and responses. Timing mechanisms, stimulus presentation, and data recording instructions expand the operations available within the language.     

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.     

The use of digital video recorders (DVRs) for capturing digital video files for use in both The Observer and Ethovision

Before switching a laboratory from analog to digital, for the recording of video files for use in Noldus software such as Ethovision and The Observer, researchers need to proceed with caution. There are obvious advantages in moving to digital recording for behavioral work, including increased storage capacity; no requirement to purchase video tapes; immediate search by date, time, or event; digital images are of higher quality; ability to view study sites remotely by Internet connection; and “smart” features, such as motion detection. But before you throw away your time-lapse video recorders, time code generators, and video multiplexors, there are some important cautions to take account of. Some research groups have bought digital surveillance systems on the assumption that they work with Ethovision and The Observer, only to be disappointed. The vast majority of systems depend on proprietary compression software that must then be converted to work properly in Ethovision or The Observer.     

UCSD PASCAL with a VAX as a floppy disk

The increasing sophistication of laboratory microcomputers has brought an attendant need for efficient programming systems. One such system, UCSD PASCAL, has been made commercially available as an adaptable package for many popular microcomputers. This paper addresses the implementation of UCSD PASCAL and describes a powerful extension of the package to use a host timesharing system as a virtual floppy-disk facility.     

The Electronically Activated Recorder (EAR): A device for sampling naturalistic daily activities and conversations

A recording device called the Electronically Activated Recorder (EAR) is described. The EAR tape-records for 30 sec once every 12 min for 2–4 days. It is lightweight and portable, and it can be worn comfortably by participants in their natural environment. The acoustic data samples provide a nonobtrusive record of the language used and settings entered by the participant. Preliminary psychometric findings suggest that the EAR data accurately reflect individuals’ natural social, linguistic, and psychological lives. The data presented in this article were collected with a first-generation EAR system based on analog tape recording technology, but a second generation digital EAR is now available.     

Applications of multiprogramming software to real-time experiments in psychology

Multiprogramming operating systems are often advertised as solving the problem of competition among independent tasks operating on the same computer system. In real-time laboratories, multiprogramming systems are much more valuable for their ability to manage the relationships among asynchronous, cooperating tasks that are part of a single experiment. This cooperation allows the programming of paradigms that would otherwise require the use of faster and more expensive hardware. Examples are given from several languages and operating systems, including the small, home-built PSYCLE system and the commercially available VORTEX II system.     

Detecting drivers’ cognitive load from saccadic intrusion

In this paper, we have explored use of Saccadic Intrusion to detect drivers’ cognitive load and instantaneous perception of developing road hazards. Saccadic Intrusion is a type of eye gaze movement which was earlier found to be related to change in cognitive load. We have developed an algorithm to detect saccadic intrusion from a commercially available low-cost eye gaze tracker and conducted four user studies involving a driving simulator and cognitive and hazard perception tests. Our results show that average velocities of saccadic intrusion increases with increase in cognitive load and recording saccadic intrusion and eye blinks for 6 s duration can predict drivers’ instantaneous perception of developing road hazards.     

Using a laboratory computer for identification of nonlinear behavioral and electrophysiological systems

A system for mathematically identifying unknown nonlinear systems based upon Wiener kernels and G-functionals is presented as an example of the sophisticated analyses of electrophysiological and behavioral data made possible by the introduction of powerful digital computers to the laboratory environment. The applicability of these methods to a wide variety of systems is emphasized. By measuring the response of the unknown system to appropriate white noise stimulation, data may be obtained which are sufficient for the characterization of the system under test. The only restrictions upon the unknown system is that it be approximately stationary during the period of measurement and that its output depend upon its input in the finite past. Various pretests to evaluate the applicability of the method are presented. Simple FORTRAN programs that clarify the methods of computation are given for the preprocessing of data, the analysis of lower-order kernels, the synthesis of system response from the computed kernels, and the computation of the proportion of the variance in the systems output which is accounted for by the kernels zero, one, and two. These programs may be implemented on a digital laboratory computer of moderate size. Analysis may be performed either on-line or after data collection, depending upon the temporal characteristics of the system under test. This method represents one of the few analytical techniques presently available for the characterization of both linear and nonlinear systems. For this reason, it constitutes a uniquely powerful tool for many branches of psychology. Successful applications of this method to electrophysiological and behavioral data are mentioned. Limiting factors in the use of Wiener kernel analysis are also discussed.     

Analyzing individual differences in sentence processing performance using multilevel models

The use of multilevel models is increasingly common in the behavioral sciences for analyzing hierarchically structured data, including repeated measures data. These models are flexible and easily implemented via a variety of commercially available statistical software programs. We consider their application in the context of an eye-movement experiment testing readers' responses to a semantic plausibility manipulation in temporarily ambiguous sentences. Multilevel models were used to study the relationship between working memory capacity and the extent to which readers were disrupted by syntactic misanalysis. This represented a cross-level interaction between an individual difference measure and a sentence-level characteristic. We compare a multilevel modeling approach to a standard approach based on ANOVA.