Automatic control of stimulation

How can I automatically set a repeating stimulus to stop when a defined response is detected?

I'm trying to repeat the experiments of Shahaf and Marom (2001). To do this I need to stimulate (e.g. with 1 Hz pulses) a cortical culture and monitor the rate of response in a selected electrode(within 50ms of the stimulation) so that when the frequency of response increases (e.g. from less than one response in ten stimuli to 2 or more responses in 10 stimuli) the stimulation is stopped, rested for five minutes and started again.
Specifically, I don't know how to stop the stimulus when the frequency threshold is reached.

I'm using STG 1008 with MCstimulus to control the stimulation.

Many thanks

Rob

Dear Rob,

you can connect the Sync Out output of the STG to the digital input of the MC_Card. Insert a trigger detector into your rack and select the digital channel as input channel (for details refer to 'Using the digital data stream for triggering' of the MC_Rack online help). Now you can insert an analyzer into your rack and trigger the analyzer with the Sync Out output of the STG. This means that you can determine the time during which data is analyzed with the Synch Out signal and the ROI settings of the analyzer (see the chapter 'Analyzing Data' of the MC_Rack online help). If the analyzer delivers for example spike rates as output you can insert a second trigger detector which produces a trigger event when the spike rate exceeds a certain value (see 'Using a raw data or a parameter stream for triggering'). Insert the Digital Out instrument into your rack and select this last trigger as input (see the chapter 'Digital Output' of the MC_Rack online help). You will get a pulse at the digital output port of MC_Card each time the spike rate exceeds the chosen value. Note that there is a typical internal delay between the trigger event and the TTL pulse of about 300 ms.
You can connect this bit of the digital output port of MC_Card with the Trig In input of the STG. The Trig In input starts or stops the STG (see 'Triggering Stimulation' of MC_Stimulus online help). Note that you need a DigOut connector for your computer and the MC_Card driver version 2.5 or higher.

best regards
Gerald