Tonic and burst firing: dual modes of thalamocortical relay. Trends Neurosci

Department of Neurobiology, State University of New York, Stony Brook, New York, NY 11794-5230, USA.
Trends in Neurosciences (Impact Factor: 12.9). 03/2001; 24(2):122-6. DOI: 10.1016/S0166-2236(00)01714-8
Source: PubMed

ABSTRACT All thalamic relay cells exhibit two distinct response modes--tonic and burst--that reflect the status of a voltage-dependent, intrinsic membrane conductance. Both response modes efficiently relay information to the cortex in behaving animals, but have markedly different consequences for information processing. The lateral geniculate nucleus, which is the thalamic relay of retinal information to cortex, provides a reasonable model for all of thalamus. Compared with burst mode, geniculate relay cells that are firing in tonic mode exhibit better linear summation, but have poorer detectability for visual stimuli. The switch between the response modes can be controlled by nonretinal, modulatory afferents to these cells, such as the feedback pathway from cortex. This allows the thalamus to provide a dynamic relay that affects the nature and format of information that reaches the cortex.

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    • ", 2002 ) . When coding for comparable signals , bursts , in comparison with single spikes , have been shown to improve the SNR ratio ( Sherman , 2001 ) and are suggested to improve information transfer between neurons ( Lisman , 1997 ) . "
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    Frontiers in Physiology 07/2015; 6(208). DOI:10.3389/fphys.2015.00208 · 3.50 Impact Factor
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    • "However, combined application of Ino with muscimol, bicuculline and theophylline (Fig. 4B, D, F) suggests that absence epileptic activity increasing effect of Ino results mainly from the increase of inhibitory tone via thalamic GABA A receptors and/or by thalamic A 2A receptors evoked increase in GABAergic functions in WAG/Rij rats. In relation to Ino-evoked effects on absence epileptic activity, it is interesting to note that the excitatory tone increasing GABAergic antagonists and Ado receptor antagonists decreased absence epileptic activity (Peeters et al., 1989; Ates et al., 2004) whereas absence epileptic activity aggravated by increasing the inhibitory tone by Ado, GABAergic agonists and GABA reuptake blockers (Peeters et al., 1989; Coenen et al., 1995; Ilbay et al., 2001) probably because membrane hyperpolarization in thalamic relay neurons is necessary to evoke SWDs via burst firing mode (Sherman, 2001; Cope et al., 2009; Crunelli et al., 2012). In addition, augmented thalamic (relay nuclei) GABA A receptor subunit (a 4 and d) expression evoked increase in tonic inhibition of thalamic neurons may be in relation to the exacerbation of absence epileptic seizures in symptomatic WAG/Rij rats (Pisu et al., 2008). "
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    Neuroscience 05/2015; 300. DOI:10.1016/j.neuroscience.2015.05.054 · 3.33 Impact Factor
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    • "The investigated range of thalamocortical sensory input firing rates was between 100 and 12,000 spikes/s. This translates into firing rates of thalamocortical cells in the range of 1–120 spikes/s, which is in agreement with the reported firing rates of thalamocortical cells in the tonic firing mode (McCormick and Feeser 1990; Sherman 2001). In simulations of tactile stimulation, we took into account the rapidly adapting and slowly adapting responses of peripheral receptors. "
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    Journal of Neurophysiology 09/2014; DOI:10.1152/jn.00844.2013 · 3.04 Impact Factor
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