The script
<ep> <cr> <fd 1> <d 119> <t 1500> <id keyboard>
<dbc 210210210> <dfs
36> <dwc 0 ><vm
1024,768,768,16,60> <nfb><rcot> <eop>
! This is a very simple
demo of a lexical decision task;
! last
edited on
! Item number AB;
! A=condition (1=word,
2=non-word);
! B=Trial number;
0 ”Press SPACEBAR to start”;
+11 * “RABIES”<% 30>/;
-22 * “BRANTLY” <%
30>/;
-23 * “SKELVE” <%
30>/;
+14 * “JUMP” <%
30>/;
0 ”The END! Thank you for your participation”;
The output file
Subjects incorporated to
date: 001
Data file started on
machine EVO
**********************************************************************
Subject 1, 11/07/2005
19:32:08 on EVO, refresh 16.66ms, ID JJC
Item
RT COT
11
1394.86 0.00
22
1059.54 2499.18
23
-782.41 4998.36
14
607.46 7497.53
Explanation
As you can see from the COTs, each trial takes approximately 2499ms (i.e., the
difference between COTs in each trial is
2499ms). From the top of the output
file, you can determine that refresh interval is 16.66ms. From this, we know that each trial (including
the delay at the end) is 2499 / 16.66 = 150 ticks. From the header, the default delay is 119
ticks and the default frame duration is 1 tick.
Of course, we can see that this default frame duration will never be
used because we override it by specifying the timing of each frame in the
script.
Lets account for all ticks in a trial:
Rabies is presented for 30
ticks
It is erased for 1 tick
There is a delay for 119
ticks
30 + 1 + 119 = 150
ticks.