Spike–Wave Discharges: Absence or Not, a Common Finding in Common Laboratory Rats

Prominent 7to 12-Hz oscillations in the primary somatosensory cortex (S1) of awake but immobile rats might represent a seizure-like state (1) in which neuronal burst firing renders animals unresponsive to incoming tactile stimuli; others have proposed (2–4) that these oscillations are analogous to human μ rhythm (5–7). To test whether rats can respond to tactile stimuli during 7to 12-Hz oscillatory activity, we trained head-immobilized awake animals to indicate whether they could detect the occurrence of transient whisker deflections while we recorded local field potentials (LFPs) from microelectrode arrays implanted bilaterally in the S1 whisker representation area. They responded rapidly and reliably, suggesting that this brain rhythm represents normal physiologic activity that does not preclude perception.

[1]  A. Coenen,et al.  Two types of electrocortical paroxysms in an inbred strain of rats , 1986, Neuroscience Letters.

[2]  G. Micheletti,et al.  Spontaneous paroxysmal electroclinical patterns in rat: A model of generalized non-convulsive epilepsy , 1982, Neuroscience Letters.

[3]  Information Processing during Spike–Wave Discharges , 2004, Epilepsy currents.

[4]  J O Willoughby,et al.  Nonconvulsive electrocorticographic paroxysms (absence epilepsy) in rat strains. , 1992, Laboratory animal science.

[5]  Barry R. Komisaruk,et al.  Synchrony among rhythmical facial tremor, neocortical ‘ALPHA’ waves, and thalamic non-sensory neuronal bursts in intact awake rats , 1980, Brain Research.

[6]  A. Coenen,et al.  Ictal stimulus processing during spike-wave discharges in genetic epileptic rats , 2003, Behavioural Brain Research.

[7]  A. Coenen,et al.  Genetic models of absence epilepsy, with emphasis on the WAG/Rij strain of rats , 1992, Epilepsy Research.

[8]  G. Buzsáki,et al.  Spike-and-wave neocortical patterns in rats: Genetic and aminergic control , 1990, Neuroscience.

[9]  K. Kelly,et al.  Electrobehavioral characteristics of epileptic rats following photothrombotic brain infarction , 2003, Epilepsy Research.

[10]  B. Kaplan The epileptic nature of rodent electrocortical polyspiking is still unproven , 1985, Experimental Neurology.

[11]  J. Kapur,et al.  Photothrombotic brain infarction results in seizure activity in aging Fischer 344 and Sprague Dawley rats , 2001, Epilepsy Research.

[12]  D. Gauguier,et al.  Polygenic Control of Idiopathic Generalized Epilepsy Phenotypes in the Genetic Absence Rats from Strasbourg (GAERS) , 2004, Epilepsia.