The yoked control in operant conditioning 'yokes' one animal to another in terms of stimuli received. In my attempts to establish operant learning in isolated leech ganglia, if one preparation received a given number of anterior stimulation, the yoked prep would receives the exact same number of stimulations at exactly the same time points. This means that the first animal received contingent stimulation, while the second, yoked, animal receives the exact same patternof stimulations, but unrelated to the decisions it made in response to the posterior stimulation. This is the story of what happened today to preparatoion #8.

The prep started out leaning a little on the swimming side with a swimming/crawling ratio of 7-2 (one intermediate pattern) for the first ten trials. Interestingly, counter to my previous hypothesis that anterior stimulations bias the network towards swimming, this non-contingent stimulation did not have such an effect. The S/C ratio during the second ten trials was 3-5 (2 no-response trials). This is getting exciting! Maybe there is something in the contingent stimulations? Too bad that individual experiments really need validation from quite a couple of more experiments. Corroborating the trand of control preps to move towards crawling bias during the experiment, the S/C ratio in the final 10 trials was 5-5.

Tonight I'm flying to Boston for the GAIN meeting until Sunday. I'll try to blog from there...