COGNITO - Inserm

1. REACTION TIME The test measures simple reaction time using the dominant hand. When a
stimulus (a clown) appears on the screen, the subject must press the space
bar. The time recorded appears on the screen.
After reading the instructions to
the subject press the Start button
to begin the 5 Practice trials.
The subject should have his finger
just above the space bar in
preparation for each stimulus. The
practice trial may be repeated as
often as necessary if the subject
has difficulty in understanding the
instructions or begins to touch the
bar before the stimulus has
appeared.
Trials are given with random inter-trial intervals.
The reaction time is recorded to one hundredth of a second. A correct
response will be between 100 and 500 milliseconds.
If the subject responds before 100 milliseconds it is counted as an
Anticipation error. If the subject responds between 500 and 2000
milliseconds it is considered a time Lapse problem (an very slow response -
subject has probably been distracted from a correct response leading to a
possible outlier score). If the subject does not respond at all after 2 seconds it
is considered a failure (Over Time error).
The test is terminated when the subject has recorded 12 valid responses. A
maximum of 36 trials may be given.
The interviewer should only start
the real test when the instructions
are understood
In the Results file the following are recorded:
- Validity of response for each trial
- The mean of the 12 valid responses
- Total number of trials by the subject
- The number of Anticipation errors
- The number of time Lapses
- The number of Over Time errors
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