Dept of Neurophysiology -- Delayed Saccade Task Type Documentation

The Delayed Saccade Task Type (Task Type 3)

The delayed saccade task type is similar to the regular saccade task type (type 2). The difference is that the second stimulus does not start at the end of the first stimulus -- it can start either before or after the first stimulus ends. With "delayed" saccades, the animal is presented with a first stimulus, and is expected to spot or look in its direction as long as it stays on (led1dur), whether or not the second stimulus has already started. Then, if the second stimulus has already been turned on, (the user has set led2strt to be < 0), the animal is expected to look towards the second stimulus before the time period tspotl2 is over, and must continue to look there until the time stay2dur is over. If so, the animal will receive the reward, otherwise it fails the task. If, at the end of the first stimulus, the second stimulus is not on, (the user has set led2strt to be > 0), the program waits for the second stimulus to turn on, and then checks if the animal looks at it before tspotl2 is over, and if it continues to look until stay2dur is over. If so, the animal receives the reward, otherwise it fails the task.

All during this process, the COM program is collecting position data from the cat's eye (and, optionally, ear and head) and also neuronal spike data, as a function of time. After the animal either receives the reward or fails to spot a stimulus properly, the program will continue to collect data for the time period spontim (the spontaneous recording time). At the end of this time period, the trial, or task, is marked as finished, and the program then pauses for a prescribed duration known as the inter-sequence delay. (See the parameters isdrew and isdnorew.) After this, a new trial is begun. The trial process is illustrated in Figures 1a and 1b.

Figure 1a. -- Delayed Saccade Task Type (led2strt < 0)

Figure 1b. -- Delayed Saccade Task Type (led2strt > 0)

Explanation of terms for delayed saccade tasks:

first stimulus Led1 or speaker1, or both. See spk1flg and led1sel parameters to disable one or both. In Figures 1a and 1b, speaker1 is disabled.
second stimulus Led2 or speaker2, or both. See spk2flg and led2sel parameters to disable one or both. In Figures 1a and 1b, both led2 and speaker2 are used.
DSS dur Duration of auditory stimulus (speaker2 above). It depends on the duration of the stimulus waveform, as stored in the DSS. It can be less than stim2dur, but not greater than it. See also stimtyp parameter.
SY Starting point of trial.
L1 Time that led1 and/or speaker1 turns on. See led1strt parameter.
W1 Time that animal spots into window of first stimulus.
L2 Time that led2 and/or speaker2 turns on. See led2strt parameter, which can be positive or negative, and is measured relative to the end of the first stimulus.
W2 Time that animal spots into window of second stimulus.
R Time that animal receives reward.
E End of trial.

In order to execute saccade trials in the COM program, the user must set up the following files:

Fixed Parameter File - This file contains the list of parameters that retain the same values for all trials of a given run of the COM program. There are at least 50 parameters in this list, and they must be specified whenever COM is run. Here is an example of such a fixed parameter set.
Saccade Parameter File - This file contains the list of parameters that define a set of saccade trials. The user may specify one or more of these files, each containing a different saccade parameter set. Here is an example of one such parameter set.
Macro File - This file contains the list of parameter sets to be used for a run of the COM program. It must contain one fixed parameter file, and one or more parameter set files, as described above. Here is an example of one such macro file.

Note that while a given trial is being executed, the user can type one of several available commands. The program will complete the current trial (so as not to disturb the timing of the trial), and will then process the command that has been typed.

Com Program Documentation -- General
Task Types
Saccade Task Type
Glossary of Parameters -- definitions of all parameters used

If you have questions or comments about this documentation, please send email to jane@neurophys.wisc.edu

This page last modified on : June 26, 1996

first stimulus	Led1 or speaker1, or both. See spk1flg and led1sel parameters to disable one or both. In Figures 1a and 1b, speaker1 is disabled.
second stimulus	Led2 or speaker2, or both. See spk2flg and led2sel parameters to disable one or both. In Figures 1a and 1b, both led2 and speaker2 are used.
DSS dur	Duration of auditory stimulus (speaker2 above). It depends on the duration of the stimulus waveform, as stored in the DSS. It can be less than stim2dur, but not greater than it. See also stimtyp parameter.
SY	Starting point of trial.
L1	Time that led1 and/or speaker1 turns on. See led1strt parameter.
W1	Time that animal spots into window of first stimulus.
L2	Time that led2 and/or speaker2 turns on. See led2strt parameter, which can be positive or negative, and is measured relative to the end of the first stimulus.
W2	Time that animal spots into window of second stimulus.
R	Time that animal receives reward.
E	End of trial.