A common feature of temporal lobe epilepsy and of animal models of epilepsy is the growth of hippocampal mossy fibers into the dentate molecular layer, where at least some of them innervate granule cells. Because the mossy fibers are axons of granule cells, the recurrent mossy fiber pathway provides monosynaptic excitatory feedback to these neurons that could facilitate seizure discharge. We us...

Definitive evidence is presented that the conditioned stimulus (CS) in classical conditioning reaches the cerebellum via the mossy fiber system. Decerebrate ferrets received paired forelimb and periocular stimulation until they responded with blinks to the forelimb stimulus. When direct mossy fiber stimulation was then given, the animals responded with conditioned blinks immediately, that is, w...

The synapse made by hippocampal mossy fibers onto pyramidal neurons of hippocampal area CA3 displays a form of long-term potentiation (LTP) that is independent of the activation of NMDA receptors. Considerable controversy exists as to whether the induction of mossy fiber LTP requires postsynaptic activation and, thus, whether mossy fiber LTP is Hebbian or non-Hebbian. Here we report the inducti...

Precise representation of the timing of sensory stimuli is essential for rapid motor coordination, a core function of the cerebellum. Feedforward inhibition has been implicated in precise temporal signaling in several regions of the brain, but little is known about this type of inhibitory circuit within the input layer of the cerebellar cortex. We investigated the synaptic properties of feedfor...

Three main types of pathological change are recognized in the hippocampus in children with epilepsy: neuronal loss and gliosis, mossy ®bre sprouting and dentate dispersion. In mesial temporal sclerosis (MTS) there is increasing evidence that cell loss in speci®c sub®elds of the hippocampus may be related to age at precipitating injury. The relationship of febrile or complicated seizures to MTS ...

Treatment with pilocarpine (PILO) induces variable degrees of loss of mossy cells (MCs) and mossy fibre (MF) sprouting in rodents, the relationships of which have not been examined in individual animals. Our aim was to test whether the loss of MCs and MF sprouting are coupled processes in PILO-treated rodents. Animals which exhibited intense PILO-induced convulsions for at least 30 min were use...

occurring mouse mutants with defects in cerebellar differentiation , the cerebellum has been a favored system New York, New York 10016 for studying neural development. GC precursors begin to migrate from the external to internal granular layer approximately 1 week after birth in the mouse. Mossy Following neurogenesis and the initial steps of axon fiber axons, waiting in the internal granular l...