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How to make a target appear and then disappear

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Hello, I am new to MatLab and working on an experiment where a participant will be moving their eyes from one dot to another. I have created a rudimentary figure with associated code which contains the basic design that our team wants. I would like to make the dot on the right appear for 0.3 seconds and then disappear but am stuck trying to figure that out. I would greatly appreciate any help. Feel free to reach out via email at djcvan@uw.edu if that would be easier.

Answers (2)

Geoff Hayes
Geoff Hayes on 2 Jun 2022
@Dax Cvancara - try using a timer to delete the graphics object (of the right dot) after 0.3 seconds. Nest your code into a main function like this
function plotv1
gazeFigure = figure('color','black','KeyPressFcn',@keyboardFunction); % Create background
gazeAxes = axes('color','black','XLim',[0 2.0],'YLim',[0 2.0]); % define the axis
gazeFixation = line(1,1,'marker','.','markersize',50,'color',[1 1 0]); %Central fixation point
gazeTarget = line(1.5,1,'marker','.','markersize',50,'color',[1 1 0]); %Target point
timerObj = timer('TimerFcn', @timerCallback, 'StartDelay', 0.3, 'ExecutionMode', 'singleShot');
start(timerObj);
function timerCallback(~, ~)
delete(gazeTarget);
end
end

Walter Roberson
Walter Roberson on 2 Jun 2022
For work such as this, I recommend that you use the third-party Psychtoolbox, which is designed to be able to create precise timing of stimulus.
  1 Comment
Dax Cvancara
Dax Cvancara on 6 Jun 2022
@Walter Roberson I am attempting to download it now but it has been a challenge as I am using a old computer (windows 32-bit) without access to the internet. Will hopefully have it downloaded by the end of the day.

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