Detection of subthreshold pulses in neurons with channel noise.
Neurons are subject to various kinds of noise. In addition to synaptic noise, the stochastic opening and closing of ion channels represents an intrinsic source of noise that affects the signal-processing properties of the neuron. We study the response of a stochastic Hodgkin-Huxley neuron to transient input subthreshold pulses. It is found that the average response time decreases but variance increases as the amplitude of channel noise increases. In the case of single-pulse detection, we show that channel noise enables one neuron to detect the subthreshold signals and an optimal membrane area (or channel noise intensity) exists for a single neuron to achieve optimal performance. However, the detection ability of a single neuron is limited by large errors. Here, we test a simple neuronal network that can enhance the pulse-detecting abilities of neurons and find that dozens of neurons can perfectly detect subthreshold pulses. The phenomenon of intrinsic stochastic resonance is also found at both the level of single neurons and the level of networks. At the network level, the detection ability of networks can be optimized for the number of neurons comprising the network.
Chen
Yong
Y
Institute of Theoretical Physics, Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, Lanzhou 730000, China. ychen.ch@gmail.com
Yu
Lianchun
L
Qin
Shao-Meng
SM
D000818:Animals; D007473:Ion Channels / Q000502:physiology*; D008564:Membrane Potentials / Q000502:physiology; D008959:Models, Neurological; D009415:Nerve Net / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D009482:Neurophysiology / Q000379:methods; D009622:Noise; D015221:Potassium Channels / Q000502:physiology; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012684:Sensory Thresholds; D015222:Sodium Channels / Q000502:physiology; D013269:Stochastic Processes
D007473:Ion Channels; D015221:Potassium Channels; D015222:Sodium Channels