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directionselectivityNcelldemo_thresh

  DIRECTIONSELECTIVITY4CELLDEMO_thresh - Demo of a N*R input, single layer direction-selective output cell with rising threshold

   [MODELEL, DI, R_UP, R_DOWN] = DIRECTIONSELECTIVITYNCELLDEMO_thresh

   Enter "TYPE DIRECTIONSELECTIVITYNCELLDEMO_THRESH" to see the code.

   One can modify the default parameters by passing name/value pairs to the function like this

   Default parameters are as follows:
   ----------------------------------------------------------------------
   dt (1e-4)                      |  Step size of model
   latency (0.200)                |  Latency of between rows
   lag (0.200)                    |  Lag of stimulus arrival at different positions
   N (2)                          |  Number of different positions
   R (2)                          |  Number of different latencies
   randomness (0)                 |  Coefficient of gaussian random noise that is added to lag, latency
                                  |    Note that the random value, once chosen, is used consistently each time
                                  |    a visual stimulus is presented.
   Syn_Gmax_initial (1xN*R, 4e-9) |  Initial synaptic weight (about 75% of threshold)
   plasticity_params ([])         |  Synapse plasticity params for LGN to E ctx connections
   plasticity_method ('')         |  Synapse plasticity method for LGN to E ctx connections
   isi (0.75)                     |  Inter-stimulus-interval (seconds)
   plotit (1)                     |  0/1 should we plot the behavior in a new figure?
   simit (1)                      |  0/1 Actually do simulation (1) or just build model(0)?
   simup (1)                      |  0/1 Actually simulate upward direction (1)?
   simdown (1)                    |  0/1 Actually simulate downward direction (1)?
   intfireparams                  |  {'name1','value1'} parameter list to pass to intfireleakyel_init
   synapseparams                  |  {'name1','value1'} parameter list to pass to synapset1t2el_init
 %  synapseparams_ffI              |  {'name1','value1'} parameter list to pass to synapset1t2el_init for feedforward connections to I cell
                                  |    default value {'V_rev',-0.080}
   V_threshold (-0.055)           |  Threshold value (volts)
   slow (0)                       |  Show stimulus at half speed?
   mask (1)                       |  Mask out any input cells?
   phase ([1:N])                  |  Order in which to move bar to different positions (default 1, 2, 3, etc)


   Outputs:
   MODELEL is the model produced by the function.  
   DI is (R_UP-R_DOWN) / (R_UP+R_DOWN), note this is -1 to 1
   R_UP is response to upward direction
   R_DOWN is response to downward direction

   Examples:
      % a totally non-direction-selective model
      [mel,di,rup,rdown]=directionselectivityNcelldemo_thresh;

      % a direction-selective model
      [mel,di,rup,rdown]=directionselectivityNcelldemo_thresh('Syn_Gmax_initial',[0 5 5 0]*1e-9);

      % a 3 by 3 cell model
      [mod,di,r_up,r_down] = directionselectivityNcelldemo_thresh('N',3,'R',3,'isi',1);

      % a 10 position by 3 latency cell model:
      [mod,di,r_up,r_down] = directionselectivityNcelldemo_thresh('N',10,'R',3,'isi',3);

   See also: INTFIRELEAKY_SYNAPSEDEMO