Recent reports have suggested that chaos control techniques may be useful for electrically manipulating epileptiform bursting @entity146 . Because the dynamics of spontaneous in vitro bursting had not been well determined previously, analysis of this behavior in the @entity35 hippocampus was performed. Epileptiform bursting was induced in transverse @entity35 hippocampal slices using three experimental methods. Slices were bathed in artificial cerebrospinal fluid containing: (1) elevated @entity972 ([K+]o= 10.5 mM), (2) zero @entity1760 , or (3) the GABAA-receptor antagonists @entity1027 (20 microM) and picrotoxin (250 microM). The existence of chaos and determinism was assessed using two different analytical techniques: unstable periodic orbit (UPO) analysis and a new technique for estimating Lyapunov exponents. Significance of these results was assessed by comparing the calculations for each experiment with corresponding randomized surrogate data. UPOs of multiple periods were highly prevalent in experiments from all three @entity302 models: 73% of all experiments contained at least one statistically significant @entity7702 or period-2 orbit. However, the expansion rate analysis did not provide any evidence of determinism in the data. This suggests that the system may be globally stochastic but contains local pockets of determinism. Thus, manipulation of bursting behavior using chaos control algorithms may yet hold promise for reverting or preventing @entity302 .

Deterministic chaos and noise in three in vitro hippocampal models of XXXX .

@entity7702 :: ('287422(Tax:10116)', 'Gene') :: ['period-1'] @entity146 :: ('MESH:D001523', 'Disease') :: ['behavior in neuronal ensembles'] @entity1027 :: ('MESH:D001640', 'Chemical') :: ['bicuculline'] @entity302 :: ('MESH:D004827', 'Disease') :: ['epileptic seizures', 'epilepsy'] @entity972 :: ('MESH:D011188', 'Chemical') :: ['potassium'] @entity35 :: ('10116', 'Species') :: ['rat'] @entity1760 :: ('MESH:D008274', 'Chemical') :: ['magnesium']
@entity302 :: (MESH:D004827,Disease) :: ['epilepsy']
