Path: utzoo!attcan!uunet!lll-winken!lll-tis!helios.ee.lbl.gov!pasteur!ucbvax!HNYKUN53.BITNET!VDPLAATS
From: VDPLAATS@HNYKUN53.BITNET
Newsgroups: comp.sys.atari.st
Subject: (none)
Message-ID: <8806101635.AA23858@ucbvax.Berkeley.EDU>
Date: 10 Jun 88 11:15:00 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 98

From: VDPLAATS@HNYKUN53.BITNET (Ruud van der Plaats)
To  : info-atari16@score.stanford.edu
Subj: ST for Psychological Experiments

> Does anyone of you use or know how to use the Atari ST for experiments in
> which a visual stimulus is presented on the screen and reaction time is
> measured by the same machine. A friend of mine wants to know if he could
> use the ST for this. He would like to measure time with millisecond accuracy!
>                            Henk van der Griendt.
>                            Institute for Perception Research IPO
>                            Eindhoven, The Netherlands
>                            E-Mail: VDGRIENDT@HEIIPO5   (EARN/BITNET)

 Nice Subject! We use twelve ST's as jack of all trades in our department.

 Noud van Kruysbergen has developed a fast timer interrupt routine in
 assembler which can easily be used in C. Adaption to GFA Basic is in
 progress. The ST is equipped with 4 timers of which the A-timer is free.
 The interrupt is executed 10.000 times per second which yields an accuracy
 of 0.1 msec. Higher frequencies(=accuracy) can be achieved, but this will
 suppress other tasks during timing.
 An external timer button can not be connected to the mouse or joystick ports
 but has to be linked to a port of which the status is directly readable.
 Examples are the printerbusy signal of the parallel printer port or the CTS,
 DCD, RI (with the RTS) signals of the serial (RS-232) port. So you need to
 adapt, e.g., the RS232 port to use such a routine. The timer can start,
 reset and/or read by means of manipulating global variables.

 Here are some applications for the ST we use in psychological experiments
 and testing in our department.

 - Timed presentation of digitized sound samples and tones of variable
   duration, volume and frequency:

  We use very nice low cost 8 bits AD/DA cartridge hardware and STRACK
  software, both distributed in Holland by Atari Club Nederland (ACN)
  Haarlem (price app. $ 75). Part of the STRACK software has been patched
  in cooperation with the author to provide high quality D/A output via the
  cartridge from within GFA Basic. A homebrew Gfa program loads a set of
  digitized sounds and a control file containing time, duration and frequency
  parameters of tones and sounds. The tones are generated by the internal
  sound chip of the ST.
  There are two ways to present the sound to subjects. A low quality
  presentation is possible via the internal sound chip and speaker (no
  cartridge needed during replay). A high quality sound reproduction is
  possible via the D/A of the cartridge. We use the cartridge route to
  present auditive stimuli. The tones of the sound chip are used as the 'go'
  signal for the subject and can serve as trigger for other computers
  (like the PDP) to start some recording.
  The system has been used succesfully to create long audio tapes with
  a fairly complex sequence of sounds and beeps. For questions mail to
  Lambert Schomaker (SCHOMAKE@HNYKUN53).

 - Teaching speech to deaf children.

  In this project an Atari ST was used as a visual display to interact with
  the teacher/pupil. A pull-down menu controlled the mode of operation and
  selected the graphic display. Visual dimensions like form, size, color,
  texture, movement and location were used to visualize all aspects relevant
  for speech training. Programming was done in GFA-Basic, which proves itself
  as a fast development tool. Nico Arends (POVEL@HNYKUN52) knows all about
  this.

 - Computerized psychological testing.

  The General Aptitude Test Battery (GATB) has been implemented on the ST
  in Pascal. The first seven tests can be used with full GEM and mouse support.
  The visual displays are coded in a very economical way. Frans Maarse
  (MAARSE@HNYKUN53) is responsible for technical support and can answer
  questions on this subject.

  A computerized version of Kelly's Repgrid Personality Test (CAGE) has been
  developed in Gfa Basic and Turbo Pascal (IBM PC). The test works with GEM
  and is mouse driven. A principal component analysis and varimax rotation
  is done on the matrix scores. Results are presented by a graph. Frits van
  Heekesen (U212997@HNYKUN11) can give more information.

  Other applications are an ST in combination with a digital scope program
  (Digitalis 4+, Computertechnik Zaporowski) which is used to monitor the
  input level of EMG and speech signals and some drawing programs in C used
  to record the time handicapped children need to draw segments. Frits also
  wrote a program which can present auditive and visual stimuli on the ST.

 The ST has one problem in serving psychological experiments: the beast has
 no slots. On the other hand, its great graphics, compact size, large working
 memory and low price are attractive compared to the average IBM PC (-clone).

 We would like to get in contact with other experimental psychologists
 that use ST's on their work. Maybe we can exchange some dedicated software.
 Or is the use of the ST in this respect confined to The Netherlands ?

 (I hope I didn't bore all you non-psychologists to death with this)

                                          greetings,
 Bitnet: vdplaats@hnykun53                Ruud van der Plaats
 or: vdplaats@hnykun53.BITNET             Department of Experimental Psychology
                                          NICI
 vdplaats%hnykun53.BITNET@RELAY.CS.NET    University of Nijmegen
 ...mcvax!vdplaats%hnykun53.BITNET        The Netherlands.