on-line processing of psychophysiological data from patients receiving biofeedback. A data acquisition .... There are basically three modes of data retrieval:.
Behavior Research Methods & Instrumentation 1976, Vol. 8 (2), 235·237
Automated psychophysiology laboratory PETER G. STENN. H. DOMINIC COVVEY. CARLYLE SCASE, GILBERT F. D. HESELTINE University Hospital; London, Ontario. CanadaN6G 2K3 A laboratory has recently been established in University Hospital based on a PDP-llI40 processor running a real-time Executive (RSX-ll/D) which has storage and data acquisition peripherals to handle on-line processing of psychophysiological data from patients receiving biofeedback. A data acquisition program has been written which permits the sampling of eight simultaneous channels of data coming from a Hewlett-Packard 7700 electrophysiological recorder system. Input from the patient includes switch closures and variable resistors, thermistors, GSR, electrocardiogram, respiration rate, and a variety of ethers. Feedback to the patient includes a variety of types of lights. a cathode ray tube storage screen, a character-oriented CRT monitor, and a variety of audio signals. Developers are presently involved in writing the biofeedback section of the programs and an on-line decision-making dependent upon patient response. Simultaneously with laboratory operation, a number of other users are served. These include the Admitting Department and Respiratory Function Laboratory. A rat laboratory will be served also by this facility in the near future via a front-end microprocessor. University Hospital, a newly constructed medical and various types of auditory stimuli, various types of visual treatment center is part of the University of Western stimuli, such as flashing lights, and instructions or Ontario. The Department of Psychiatry has developed patterns on display screens. A large number of patients have been processed one laboratory and is in the process of developing a second, both of which will be devoted to research in through this laboratory. Types of research include the various problems of mental illness. One of our primary study of orientating response in schizophrenic and nonareas of interest is in the ability to perform psycho- schizophrenic subjects, the assessment of psychophysiophysiological assessments and in the ability to use bio- logical arousal, the control of muscle headaches, the control of Parkinson's type tremors, the treatment of feedback as a treatment procedure. The psychophysiological laboratory is built around a narcoleptic patients, and many others. A second laboratory IS in development to analyze the Hewlett-Packard 7700 electrophysiological recorder. This eight-channel recorder is used to acquire and record behavior of rats. Facilities associated with the rat laboraa variety of physiological signals: electrocardiograms, tory will enable us to implant electrodes and chemoheart rate, electroencephalograms, galvanic skin trodes, and to conduct research on the brain. We are resistance, skin temperature, lung pressure and volume primarily interested in studying the effect of certain psychanges, respiration rate, and electrooculograms. This chornimetic drugs such as dimethyl tryptamine (DMT), system was designed to be very flexible and is inter- 5-methoxy-dimethyl tryptamine (5-MEO DMT), and 5hydroxy-dimethyl tryptamine. It is expected that the faced to a computer in an adjoining room. The computer which records and analyzes data behavioral laboratory will be operational in 1976. It is generated by the polygraph is a Digital Equipment envisioned that a microprocessor will be interfaced to Corporation PDP-I 1/40 running the real-time Executive the PDP-II to handle the running of the different boxes. RSX-Il/D. HARDWARE This combination of electrophysiological recorder and computer enables researchers to make rapid Equipment has been assembled at University measurements of many parameters simultaneously and includes the capability for real-time analysis and Hospital, which is presently utilized by the Department decision making. There also exists the ability to provide of Psychiatry and shared by a number of other departvarious types of stimuli back to the patient. This ments. The equipment includes a PDP-I 1/40 computer stimulus presentation can be made contingent on a with 12K words of 16-bit core memory (900-nsec rather complex series of physiological events. The types cycle time). This computer has the following of stimulation that can be delivered include: turning a peripherals: (1) two cartridge disk drives (2.4 megabytes tape recorder off or on, slide projection, providing each), (2) an analog-to-digital subsystem (LPS.II), (3) a programmable real-time clock, (4) an extended instrucThis project is supported by the Richard and Jean Ivey Fund. tion set and hardware floating point arithmetic proWe wish to thank Sharon Colwill, Department of Computer cessor, (5) a 30-eharacter/sec hard-eopy printer, (6) two Applications, University Hospital, for her help. Address requests cathode ray tube terminals, (7) a mark-sense card or for reprints to H. D. Covvey, University Hospital, 339 Windermere Road, London, Ontario, Canada N6G 2K3. punched card reader (300 cards/min), (8) an optical
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236
STENN, COVVEY, seASE, AND HESELTINE
reduced room
8
Chan.
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•
•
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up to 8 channels
-tr I
I I
One way .Mirror
HIP 7700
Signal Pre-process
Tr LPS
AID
LPS
DI
LPS
DO
LPS DISPLAY
Figure 1. Psychophysiology Data Acquisition Laboratory.
mark document reader for reading mark-sense forms (OPSCAN/17), (9) the necessary multibaud rate communications interfaces, (10) facilities for synchronous communication including a 2400 BPS communications controller with a hardware error checking facility, (11) memory management, (I 2) various hardware added for real-time applications, (13) a remote terminal in the Admitting Department, (14) a remote terminal in the Respiratory Function Laboratory. SOFTWARE The software system is the RSX-ll/D Version 6. The primary applications language is FORTRAN IV. Realtime programming and special language additions are written in the MACRO ASSEMBLER. This facility is connected to an IBM 370/168 at the London Life Insurance Company via a synchronous communications system 2780 emulator. The 370 is used to do electrocardiographic analysis under a project funded by an Ontario Heart Foundation grant to the Division of Cardiology at University Hospital (G. Manning). Time on the 370 is donated by London Life. In addition, we are connected via a low-speed asynchronous communications link to the PDP-l 0 at the University of Western Ontario. We utilize this facility heavily for program development, forms development,
and statistical data processing. Via our synchronous communications handler, we have access to a number of other processors on the campus, but these connections are only in the planning stages.
DESCRIPTION OF HARDWARE SYSTEM The psychophysiology laboratory area is diagrammed in Figure 1. The patient is seated in a "relaxation chair" and signals are obtained in the standard way. A therapist may be present with the patient for the purpose, for example, of relaxation therapy. Both the therapist and the patient can be viewed through a one-way mirror by a psycho technician in the adjoining processing area. All signals have the option of being preprocessed. Either the raw or processed signals are recorded on a HewlettPackard Model 7700 thermal paper recorder and passed on, if desired, to the PDP-l 1/40 computer system. Table 1 gives a rough outline of the types of signals that can be obtained from the patient, preprocessed and recorded, and (presently) used for computer input. The various signals are digitized by the Laboratory Peripheral System (LPS) at a rate of usually less than 10 samples! sec. Up to eight channels passed on by the technician can be digitized using the LPS. In addition, switch closures, buttonpresses, or their equivalent can be input directly via the Laboratory Peripheral System digital
AUTOMATED PSYCHOPHYSIOLOGY LAB Table I Signals, Preprocessing, Input Preprocess and Paper Record
Computer Input
Integrate Raw Heart Rate Raw Respiration Rate Raw Raw
Integrated EMG Heart Rate Raw Respiration Rate Raw Skin Temp Raw GSR
Patient 1. EMG
2. ECG 3. RESP
4. Skin Temp 5. GSR
Filter Output
6. EEG
7. Switch or Equiv, Closures 8. Variable Pots
Any Channel
Computer Input
Theta Detect Delta Integrate/Unit Time Alpha Integrate Beta
Detected Band Integrate/Time Band Int egrated Band
Raw
Raw
Raw
Raw
237
DESCRIPTION OF SOFTWARE SYSTEM There are basically three sections to the psychophysiology laboratory software system: (I) experimental design, (2) data collection, (3) data retrieval.
Experimental Design (RTINIT) Using the experimental design section, the psychotechnician can define the following control parameters: (1) the channels to be sampled, (2) the sampling rate (presently the same for each channel), (3) the experiment length, (4) the averaging interval, (5) channels to be displayed back on the storage oscilloscope, (6) calibration parameters for each channel, and (7) information concerning the subject. The controller portion saves the experimental design in a data file and starts and stops the data sampling task. In addition, this routine has the responsibility of saving the raw data and providing averaging of groups of points if this is desired. The controller queues requests to the data display task and controls the length of data collection. Calculations can be performed by the controller if these are desired by the operator, and, hence, this acts as the processing portion of the program during the experiment.
inputs. Up to 16 channels of digital input can be processed this way. Data are recorded on disk by the data acquisition program and later processed. Feedback is provided to the patient directly by analog and digital subsystems off-line. Any of the above mentioned signals can be subjected to zonal processing. Up to four channels can be gated simultaneously to proData Collection vide a multipararneter zone. The system has the capability of producing Virtually The data collection section samples the appropriate any audio feedback over a high-fidelity audio intercom channels at each interval specified in the experimental system. An audio mixer allows signals, voice, and music design. When the sampling is done on the specified to be mixed and turned on or off contingent on signals. channels, it sets the sampling-done flag for the Visual feedback is provided with the usual devices. controller. This task then waits for the next sampling We are planning to provide feedback through the time. computer system, which at this point is used for assessThe data display portion displays data and zones on ment and recording purposes only. Feedback will be the oscilloscope at each request of the controller given using existing hardware attached to the digital out- routine. put portion of the Laboratory Peripheral System. The Laboratory Peripheral System uses the Tektronix 613 storage oscilloscope to provide displays to the patient. Data Retrieval The objective of our work to date has been to There are basically three modes of data retrieval: establish extremely flexible input and output facilities (1) The operator can retrieve and display data segments with the option of completely off-line handling of the on the oscilloscope. (2) A disk storage section provides patient. The system thus allows for the simpler types of for off-line calculation or processing. (3) Data segments biofeedback to be accomplished without any involve- may be dumped onto the printer as raw values or caliment of the computer system. brated for voltage.
