How can I push simultaneously two toggle buttons without stopping the execution of one button in Matlab GUI

Hello,

I'm quite new in using Matlab Guide and I've a question. I'm trying to create a simple interface of data encoding. The goal of the interface is to fill in a matrix with 0 and 1 when an activity is done or not in a video file. Obviously, when we push a button, then the value 1 appears in the storage matrix. So in Guide, I defined a zero matrix, I create toggle buttons for activities, so for each activity (i.e. each button), I put this code:

% --- Executes on button press in Grazing_start.
function Activity1_start_Callback(hObject, eventdata, handles)
% hObject    handle to Activity1_start (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

%Hint: get(hObject,'Value') returns toggle state of the togglebutton
time = handles.time; %time in seconds, initially time = 1%
be=handles.be; % be is a zero matrix initially
a=get(hObject,'Value');
while a==true
    be(time,2)=1;%If I'm pushing the Activity1 button, then put 1 in the 'be' matrix
    time=time+1;
    handles.time=time;
    handles.be=be;
    guidata(hObject,handles);
    pause(1) %stop every 1 second for the timer
   if ~get(hObject,'Value')
        break
    end
end
guidata(hObject,handles);

While 'be' is the zero matrix I initialized at the beginning of the GUI. So I want to store the executed activities, marked by the value 1, in the matrix 'be'. My problem is that: when I push two buttons simultaneously, as two activities could occur at the same time, nothing is working. What should I change? Or how is the best way to fill this matrix relative to time?

Thanks to all.