Neuronal cell bodies in the mammalian CNS typically have more than a dozen distinct voltage-dependent conductances. The greater number of conductances compared to the squid axon is associated with much more complex firing patterns than can be produced by the squid axon. Action potential shapes and...
However, on average, neurons recorded in the cortex show a typically higher firing rate to novel stimuli67,77, which is not explained by our model. This discrepancy could be due to inherent sampling bias in electrophysiological recordings towards the most active cells78. It also may suggest the...
The latencies of the differential responses of the neurons were typically in the range 140–260 ms. The responses of these neurons reflected whether a visual stimulus had been seen recently, in that the neurons responded differently to novel and familiar presentations of a stimulus when a median ...
(2) neurons whose activity is correlated with the position of the gill and typically have a tonic output during gill withdrawal; (3) neurons whose activity is correlated with the velocity of the movement and typically fire in a phasic manner; and (4) neurons whose activity is correlated with...
However, because networkstypically have a large number of neurons, analysis of individual neurons is often ad-hoc and it’stypically not clear which ones to investigate. Moreover, a neruon’s relevance to the overall functionof network or its interactions with all other neurons is not ...
Typically, 50–100 neurons innervated a region of vasculature 1 mm in diameter. We conclude that sympathetic vasoconstrictor neurons branch widely before converging on to their target blood vessels. Progressive recruitment of vasoconstrictor neurons with increasing field size would provide an efficient ...
Although stochastic gradient descent can be considered as an approximation of gradient descent, it typically reaches convergence much faster because of the more frequent weight updates. Since each gradient is calculated based on a single training example, the error surface is noisier than in gradient ...
We also argue that results with over-complete sparse coding typically focus on the linear selectivity, but the hyper-selectivity changes in important and systematic ways as the network becomes more overcomplete. We show that the receptive fields of neurons, when measured with spots or gratings, ...
Cell viability was assessed with trypan blue at the end of transplantation and typically over 90% of the cells excluded the dye. One microliter cell suspension or vehicle (NB medium plus the cocktail of neurotrophic factors described above) was slowly injected into the right musculocutaneous nerve...
The brain is typically depicted as a complex web of neurons sending and receiving messages. But neurons only make up half of the human brain. The other half—roughly 85 billion cells—are non-neuronal cells called glia.