Fast nicotinic transmission might play a greater role in cholinergic signaling than previously assumed. We provide a model for the examination of synaptic properties of basal forebrain cholinergic innervation in the brain. “
“Nigral dopamine (DA) neurons in vivo exhibit complex firing patterns consisting of tonic single-spikes and phasic bursts that encode information for certain types of reward-related learning and behavior. Non-linear dynamical analysis has previously demonstrated the presence of a non-linear deterministic structure in complex selleck chemicals llc firing patterns of DA neurons, yet the origin of this non-linear determinism remains unknown. In this study, we hypothesized
that bursting activity is the primary source of non-linear determinism in the firing patterns of DA neurons. To test this hypothesis, we investigated the dimension complexity of inter-spike interval data
recorded in vivo Sotrastaurin cell line from bursting and non-bursting DA neurons in the chloral hydrate-anesthetized rat substantia nigra. We found that bursting DA neurons exhibited non-linear determinism in their firing patterns, whereas non-bursting DA neurons showed truly stochastic firing patterns. Determinism was also detected in the isolated burst and inter-burst interval data extracted from firing patterns of bursting neurons. Moreover, less bursting DA neurons in halothane-anesthetized rats exhibited higher dimensional spiking dynamics than do more bursting DA neurons in chloral hydrate-anesthetized rats. These results strongly indicate that bursting activity is the main source of low-dimensional, non-linear determinism in the firing patterns of DA neurons. This finding furthermore suggests that bursts are the likely carriers of meaningful information in the firing activities of DA neurons. “
“Increasing evidence shows that sensory experience is not necessary for initial patterning of neural circuitry but is essential for maintenance and plasticity. We have Proteases inhibitor investigated the role of visual experience in development and plasticity
of inhibitory synapses in the retinocollicular pathway of an altricial rodent, the Syrian hamster. We reported previously that visual receptive field (RF) refinement in superior colliculus (SC) occurs with the same time course in long-term dark-reared (LTDR) as in normally-reared hamsters, but RFs in LTDR animals become unrefined in adulthood. Here we provide support for the hypothesis that this failure to maintain refined RFs into adulthood results from inhibitory plasticity at both pre- and postsynaptic levels. Iontophoretic application of gabazine, a GABAA receptor antagonist, or muscimol, a GABAA receptor agonist, had less of an effect on RF size and excitability of adult LTDR animals than in short-term DR animals or normal animals.