Figure 4.

Effect of desflurane on the directionality index. Statistically significant change occurred in layer 5 secondary visual to layer 5 primary visual cortex (V2L5-V1L5) implying a reduction of feedback connectivity at higher desflurane concentration. Anesthetic states 1 to 9 correspond to consecutive desflurane concentrations of 0, 2, 4, 6, 8, 6, 4, 2, 0 percent, respectively. Directionality index is in relative units, plotted as mean and 95% confidence interval. *: statistically significant quadratic trend with consecutive anesthetic states.