Attracting Dynamics of Frontal Cortex Ensembles during Memory-Guided Decision-Making
Figure 5
Statistical analysis of task-epoch separation in state spaces for the many-animal single-trial data set.
Black solid curves from 8 trials in which animals performed with less than two incorrect arm choices, gray dotted curves from 8 trials where more than four incorrect arm choices were made. A. Task-epoch mean segregation errors (SE) for the good (grey) and bad (black) performance groups averaged across all task-epoch pairs (n = 14, error bars = SEM). Asterisks indicate significant differences for the comparisons indicated. For high-performance animals, a two-tailed non-parametric Wilcoxon rank-sum test was used (n = 14, p<0.04), as data significantly deviated from normality (two-sided Lilliefors test, p<0.03; Chi-square test, p<0.01). For the low-performance group, normality held (Lilliefors test, p>0.44, 0.41), and the comparison between O = 2 and O = 4 conditions is highly significant using either a t-test (p<0.0001) or Wilcoxon ranksum test (p<0.0001). Comparisons between low- and high- performance groups are also significant for O>3 (n = 14; p<0.03, Wilcoxon ranksum test). B. Individual task-epoch-pair comparisons. C. Kullback-Leibler distance between task-epoch distributions averaged across all task-epoch pairs for high- (black) and low- (gray) behavioral performance trials (asterisk and error bars as in A). Task-epoch distributions chart the probabilities of the animal being in a task-epoch C given a population activity vector ν(t), i.e. P(C|Φ(t)). See Materials and Methods for more details.