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As with the visual system, in [[mitral cell|mitral/tufted cells]] in the [[olfactory bulb]] of mice, first-spike latency relative to the start of a sniffing action seemed to encode much of the information about an odor. This strategy of using spike latency allows for rapid identification of and reaction to an odorant. In addition, some mitral/tufted cells have specific firing patterns for given odorants. This type of extra information could help in recognizing a certain odor, but is not completely necessary, as average spike count over the course of the animal's sniffing was also a good identifier.<ref>Wilson, Rachel I. (2008). [http://www.sciencedirect.com/science/article/pii/S0959438808000883 "Neural and behavioral mechanisms of olfactory perception"]. ''Current Opinion in Neurobiology'', 18(4):408–412.</ref> Along the same lines, experiments done with the olfactory system of rabbits showed distinct patterns which correlated with different subsets of odorants, and a similar result was obtained in experiments with the locust olfactory system.<ref name="Theunissen F 1995"/>
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The specificity of temporal coding requires highly refined technology to create informative, reliable, experimental data. Advances made in [[optogenetics]] allow neurologists to control spikes in individual neurons, offering electrical and spatial single-cell resolution. For example, blue light causes the light-gated ion channel [[channelrhodopsin]] to open, depolarizing the cell and producing a spike. When blue light is not sensed by the cell, the channel closes, and the neuron ceases to spike. The pattern of the spikes matches the pattern of the blue light stimuli. By inserting channelrhodopsin gene sequences into mouse DNA, researchers can control spikes and therefore certain behaviors of the mouse (e.g., making the mouse turn left).<ref name="youtube.com">Karl Diesseroth, Lecture. “Personal Growth Series: Karl Diesseroth on Cracking the Neural Code.” Google Tech Talks. November 21, 2008. http://www.youtube.com/watch?v=5SLdSbp6VjM</ref> Researchers, through optogenetics, have the tools to effect different temporal codes in a neuron while maintaining the same mean firing rate, and thereby can test whether or not temporal coding occurs in specific neural circuits.<ref name="Han X 2009">Han X, Qian X, Stern P, Chuong AS, Boyden ES. “Informational lesions: optical perturbations of spike timing and neural synchrony via microbial opsin gene fusions.” Cambridge, MA: MIT Media Lad, 2009. PubMed.</ref>
Optogenetic technology also has the potential to enable the correction of spike abnormalities at the root of several neurological and psychological disorders.<ref name="Han X 2009"/> If neurons do encode information in individual spike timing patterns, key signals could be missed by attempting to crack the code while looking only at mean firing rates.<ref name="Theunissen F 1995"/> Understanding any temporally encoded aspects of the neural code and
==See also==
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