A recent experiment showed that neurons in the primary auditory cortex of the monkey do not change their mean firing rate during an ongoing tone stimulus. The only change was an enhanced correlation among the individual spike trains during the tone. We show that there is an easy way to extract this coherence information in the cortical cell population by projecting the spike trains through depr...

Stimulus properties, attention, and behavioral context influence correlations between the spike times produced by a pair of neurons. However, the biophysical mechanisms that modulate these correlations are poorly understood. With a combined theoretical and experimental approach, we show that the rate of balanced excitatory and inhibitory synaptic input modulates the magnitude and timescale of p...

Neural coding through inhibitory projection pathways remains poorly understood. We analyze the transmission properties of the Purkinje cell (PC) to cerebellar nucleus (CN) pathway in a modeling study using a data set recorded in awake mice containing respiratory rate modulation. We find that inhibitory transmission from tonically active PCs can transmit a behavioral rate code with high fidelity...

Bath application of the GABAB receptor agonist baclofen produced a concentration-dependent long-lasting potentiation (LLP) of the evoked population spike in the dentate gyrus of rat hippocampal slices. A high concentration of baclofen (5 microM) also produced a loss of inhibition that was manifested as the appearance of epileptiform, multiple evoked population spikes and a decrease in paired-pu...

In the rat hippocampal formation, degeneration of CA4-derived afferent fibers provokes the growth of mossy fiber collaterals into the fascia dentata. These aberrant fibers subsequently form granule cell-granule cell synapses. The hippocampal slice preparation was employed to determine whether these recurrent connections are electrophysiologically functional. Hippocampal slices were prepared 12 ...

Cortical neurons in the waking brain fire highly irregular spike trains that have more in common with the ticking of a Geiger counter than of a clock. What is the source of this irregular firing? Softky and Koch1 noted a theoretical conundrum posed by the irregularity of cortical neurons firing at a constant average rate in vivo. If each cortical neuron were providing independent input to the o...

The timing of action potentials in spiking neurons depends on the temporal dynamics of their inputs and contains information about temporal fluctuations in the stimulus. Leaky integrate-and-fire neurons constitute a popular class of encoding models, in which spike times depend directly on the temporal structure of the inputs. However, optimal decoding rules for these models have only been studi...

Abstract 17 18 We explored the manner in which spatial information is encoded by retinal ganglion cell 19 populations. We flashed a set of 36 shape stimuli onto the tiger salamander retina and 20 used different decoding algorithms to read out information from a population of 162 21 ganglion cells. We compared the discrimination performance of linear decoders, which 22 ignore correlation induced...

In vivo studies have shown that neurons in the neocortex can generate action potentials at high temporal precision. The mechanisms controlling timing and reliability of action potential generation in neocortical neurons, however, are still poorly understood. Here we investigated the temporal precision and reliability of spike firing in cortical layer V pyramidal cells at near-threshold membrane...

Computational analyses have revealed that precisely timed spikes emitted by somatosensory cortical neuronal populations encode basic stimulus features in the rat's whisker sensory system. Efficient spike time based decoding schemes both for the spatial location of a stimulus and for the kinetic features of complex whisker movements have been defined. To date, these decoding schemes have been ba...