Using a logistic regression, it is possible to examine the weight of influence of the outcome of previous trials on the choice made on the present trial (Bayer and Glimcher, 2005; Lau and Glimcher, 2005). Figure 8 presents just this type of analysis, plotting the regression coefficients for the current trial (i) against each of the eight trials into the past (i-1, i-2, …, up to i-8). While the influence of reward history waned with increasing separation between the current and previous trials, control animals still appear to take into account what happened up to four trials earlier. As predicted, however, post-operatively the ACCs-group's choices were guided only by the outcome of the immediately preceding trial and none further in the past (Figure 8b).
