function trial = runChoice(disp_struct, task_struct, trial, TRAINTEST, ioObject, LTP1address)

% Fixation
JIT=Shuffle(.3:.001:.5);
fixation_text = '+';
DrawFormattedText(disp_struct.wPtr,fixation_text,'center','center');
Screen(disp_struct.wPtr, 'Flip');
WaitSecs(JIT(1));

% get the center for the screen
center_x = round(disp_struct.wPtr_rect(3)/2);
center_y = round(disp_struct.wPtr_rect(4)/2);

% define the text font
Screen('TextSize', disp_struct.wPtr, 40);
Screen('TextFont', disp_struct.wPtr, 'Times');
Screen('TextStyle', disp_struct.wPtr, 0);
Screen('TextColor', disp_struct.wPtr, [255 255 255]);
Screen('FillRect', disp_struct.wPtr,[0 0 0]);

% stimuli bounds
sWidth = 300;
sHeight = 300;
sTop = center_y - sHeight/2;
sL_left = center_x - 80 - sWidth;
sR_left = center_x + 80;
sL_rect = [sL_left, sTop, sL_left + sWidth, sTop + sHeight];
sR_rect = [sR_left, sTop, sR_left + sWidth, sTop + sHeight];

% define the left and right stimuli
if trial(task_struct.cIsS1Left)
    respL = trial(task_struct.cS1);
    respR = trial(task_struct.cS2);
    s1Rect = sL_rect;
    s2Rect = sR_rect;
else
    respL = trial(task_struct.cS2);
    respR = trial(task_struct.cS1);
    s1Rect = sR_rect;
    s2Rect = sL_rect;
end

% show the stimuli
Screen('DrawTexture', disp_struct.wPtr, disp_struct.cards(trial(task_struct.cS1)), [], s1Rect);
Screen('DrawTexture', disp_struct.wPtr, disp_struct.cards(trial(task_struct.cS2)), [], s2Rect);
io64(ioObject,LTP1address,3); WaitSecs(.05); io64(ioObject,LTP1address,0);

% see if we need to frame the nc stim
if trial(task_struct.cTrialCond) == task_struct.NC
    if trial(task_struct.cRespAct) == trial(task_struct.cS1)
        ncFrameRect = s1Rect;
    else
        ncFrameRect = s2Rect;
    end
    Screen('FrameRect', disp_struct.wPtr, [0 0 255], ncFrameRect, 5);
end % frame the fc selected stim

% limit input
RestrictKeysForKbCheck([disp_struct.RESP_L, disp_struct.RESP_R]);
KbReleaseWait();

% flip to show the stims
[VBLTimestamp StimulusOnsetTime FlipTimestamp Missed Beampos] = Screen(disp_struct.wPtr, 'Flip', 0, 1);
% %     % wait for response
% %     [secs, keyCode, deltaSecs] = KbWait([], 2, GetSecs()+task_struct.maxRT);
wait_stamp=GetSecs;
while 1
    [a ab] = JoyMEX(0);
    if find(ab) ~= 0
        if ab(1,disp_struct.RESP_L) == 1
            stim_resp = disp_struct.RESP_L;
            io64(ioObject,LTP1address,4); WaitSecs(.05); io64(ioObject,LTP1address,0);
            break;
        elseif ab(1,disp_struct.RESP_R) == 1
            stim_resp = disp_struct.RESP_R;
            io64(ioObject,LTP1address,5); WaitSecs(.05); io64(ioObject,LTP1address,0);
            break;
        end
    elseif(GetSecs-wait_stamp) > task_struct.maxRT,
        stim_resp=999;
        break;
    end
end
% compute the RT
RT = GetSecs - StimulusOnsetTime;

if stim_resp == disp_struct.RESP_L
    % left-most action
    choice = respL;
    % hide the non-selected stim
    Screen('FillRect', disp_struct.wPtr, [0 0 0], sR_rect);
    % hide selection
    Screen(disp_struct.wPtr, 'Flip');
    WaitSecs(0.75);
    
elseif stim_resp == disp_struct.RESP_R
    % right-most action
    choice = respR;
    % hide the non-selected stim
    Screen('FillRect', disp_struct.wPtr, [0 0 0], sL_rect);
    % hide selection
    Screen(disp_struct.wPtr, 'Flip');
    WaitSecs(0.75);
else
    % they didn't respond in time
    choice = disp_struct.RESP_SLOW;
end


% make sure they matched if this was a no-choice trial
if trial(task_struct.cTrialCond) == task_struct.NC && choice == trial(task_struct.cRespAct)
    trial(task_struct.cMatch) = true;
else
    trial(task_struct.cMatch) = false;
end

% do not update the response if they didn't match
if trial(task_struct.cTrialCond) == task_struct.FC || trial(task_struct.cMatch)
    % store response
    trial(task_struct.cRespAct) = choice;
    trial(task_struct.cRT) = RT;
end


% --------------------------------------- FB
if TRAINTEST==1
    % define the text font
    Screen('TextSize', disp_struct.wPtr, 60);
    Screen('TextFont', disp_struct.wPtr, 'Times');
    Screen('TextStyle', disp_struct.wPtr, 0);
    Screen('TextColor', disp_struct.wPtr, [255 255 255]);
    Screen('FillRect', disp_struct.wPtr,[0 0 0]);
    
    % get feedback for the selected stimulus
    if trial(task_struct.cTrialCond) == task_struct.NC && ~trial(task_struct.cMatch)
        fbText = 'You must match the framed symbol';
        respRew = NaN;
        SIMPLEFB=1;
        FBTRIGGER=6;
    elseif trial(task_struct.cRespAct) == trial(task_struct.cS1)
        % they picked stim 1
        respRew = trial(task_struct.cS1Rew);
        fbText = num2str(respRew);
        SIMPLEFB=0;
        FBTRIGGER=10+respRew;
    elseif trial(task_struct.cRespAct) == trial(task_struct.cS2)
        % they picked stim 2
        respRew = trial(task_struct.cS2Rew);
        fbText = num2str(respRew);
        SIMPLEFB=0;
        FBTRIGGER=10+respRew;
    else
        % they responded too slow
        fbText = ['Too Slow!\nYou must respond in under ' num2str(task_struct.maxRT) ' seconds'];
        respRew = NaN;
        SIMPLEFB=1;
        FBTRIGGER=7;
    end
    
    if respRew==0
        Screen('TextSize', disp_struct.wPtr, 100);
        Screen('TextColor', disp_struct.wPtr, [255 0 0]);
    elseif  respRew==1
        Screen('TextSize', disp_struct.wPtr, 100);
        Screen('TextColor', disp_struct.wPtr, [0 255 0]);
    end
    
    
    % show the feedback
    if SIMPLEFB==1
        io64(ioObject,LTP1address,FBTRIGGER); WaitSecs(.05); io64(ioObject,LTP1address,0);
        DrawFormattedText(disp_struct.wPtr, fbText, 'center', 'center');
        Screen(disp_struct.wPtr, 'Flip');
        WaitSecs(0.75);
        Screen(disp_struct.wPtr, 'Flip');
    else
        % FIRST show the selected stim
        Screen('DrawTexture', disp_struct.wPtr, disp_struct.cards(trial(task_struct.cS1)), [], s1Rect);
        Screen('DrawTexture', disp_struct.wPtr, disp_struct.cards(trial(task_struct.cS2)), [], s2Rect);
        % Blank out the alternative
        if trial(task_struct.cRespAct) == respL
            Screen('FillRect', disp_struct.wPtr, [0 0 0], sR_rect);
        elseif trial(task_struct.cRespAct) == respR
            Screen('FillRect', disp_struct.wPtr, [0 0 0], sL_rect);
        end
        % If forced, show the box
        if trial(task_struct.cTrialCond) == task_struct.NC
            if trial(task_struct.cRespAct) == trial(task_struct.cS1)
                ncFrameRect = s1Rect;
            else
                ncFrameRect = s2Rect;
            end
            Screen('FrameRect', disp_struct.wPtr, [0 0 255], ncFrameRect, 5);
        end
        % Next show the FB
        io64(ioObject,LTP1address,FBTRIGGER); WaitSecs(.05); io64(ioObject,LTP1address,0);
        DrawFormattedText(disp_struct.wPtr, fbText, 'center', 'center');
        Screen(disp_struct.wPtr, 'Flip');
        WaitSecs(1.25);
        Screen(disp_struct.wPtr, 'Flip');
    end
    clear FBTRIGGER;
    Screen('TextSize', disp_struct.wPtr, 60);
    Screen('TextColor', disp_struct.wPtr, [255 255 255]);
    
    % store the feedback
    trial(task_struct.cRespRew) = respRew;
end
end % function