Integrated Peripherals Support All Forms of Subject Response
(No Keyboard or Mouse Entry by Subjects)
Integrated peripherals offer comprehensive electronic data capture for a range
of complex behavioral responses, such as verbal report, bilateral reaction time,
direct voice capture, and digital graphic entry (pen). These capabilities
significantly extend the range of assessments that can be effectively
administered to impaired subjects on a computer platform.
Precise Reaction Time
Measurements
Microsoft Windows® and Vista®
are indeterminate operating systems. The time between the point of programmatic
stimulus presentation command and actual presentation cannot be measured
accurately or precisely. The optimal solution is to control stimulus
presentation and measure reaction time in the electronic domain, “outside of the
OS”. To achieve this requirement, CMINDS® features a custom hardware
solution for Zero-Phase Error reaction time measurement.
Visual Stimuli
Zero-phase error reaction time for video stimulus
events is implemented by direct monitoring of the analog video input from the
host PC. A video switch connected to a dedicated microprocessor, records the
start of screen draw using a hardware clock at well under 1 microsecond accuracy
and precision. The subject's button presses close a reed-type switch with a maximum
"bounce" under 0.3 msec. Switch closure is detected by the microprocessor with
microsecond accuracy and precision.
Audio Stimuli
Zero-phase error reaction time for audio stimulus
events is implemented by direct monitoring of the analog audio output from the final
stage audio amplifier. Sound onset is directly detected by the dedicated
microprocessor's hardware clock at well under 1 microsecond accuracy and
precision. The subject's button presses close a reed-type switch with a maximum
"bounce" under 0.3 msec. Switch closure is detected by the microprocessor with
microsecond accuracy and precision.
