Dept of Neurophysiology -- Fixation Task Type Documentation

The Fixation Task Type (Task Type 1)

In the fixation task type, the animal is presented with a stimulus, and expected to spot or look in it's direction as long as it stays on. The stimulus consists of a led/speaker pair, with either the led, the speaker, or both being turned on. If the animal succeeds in looking in the direction of the stimulus for the required duration, it receives a reward. If the animal takes longer than the time period tspotl1 to look toward the simulus, or if it looks away from it before the time period led1dur is over, then it fails the task and is not rewarded.

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 Figure 1a.

Figure 1a. -- Fixation Task Type

Explanation of terms for fixation tasks:

first stimulus Led1 or speaker1, or both. See spk1flg and led1sel parameters to disable one or both. In Figure 1a., both led1 and speaker1 are enabled.
DSS dur Duration of auditory stimulus (speaker1 above). It depends on the duration of the stimulus waveform, as stored in the DSS. It can be less than led1dur, 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.
R Time that animal receives reward.
E End of trial.

In order to execute fixation 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.
Fixation Parameter File - This file contains the list of parameters that define a set of fixation trials. The user may specify one or more of these files, each containing a different fixation 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
Glossary of Parameters -- definitions of all parameters used
Available Commands

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 Figure 1a., both led1 and speaker1 are enabled.
DSS dur	Duration of auditory stimulus (speaker1 above). It depends on the duration of the stimulus waveform, as stored in the DSS. It can be less than led1dur, 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.
R	Time that animal receives reward.
E	End of trial.