REM sleep burst neurons, PGO waves, and eye movement information

Abstract

Pontogeniculooccipital (PGO) waves appeared almost simultaneously in both lateral geniculate nuclei (LGB), but in each case on had a larger amplitude and preceded the other by a few milliseconds. The larger, earlier wave is called the primary wave. Primary waves were found to appear with equal frequency in each LGB. During rapid eye movement sleep (REM sleep), LGB primary waves were ipsilateral to the direction of rapid eye movements. During REM sleep a group of cat midbrain neurons, which we call PGO burst cells, fired in stereotyped bursts at fixed latencies before ipsilateral primary waves, but they almost never fired bursts when the primary waves were contralateral. PGO burst neuron discharge also correlated with the direction of rapid eye movements during REM sleep. In wakefulness, PGO burst cells fired single spikes, not bursts, which had some correlation with LGB waves when averaged by computer. The results suggest that PGO burst cells are output elements in the PGO wave-generation system ad that PGO waves convey eye movement information to the sensory visual system in REM sleep. They also may have a role in the production of saccade-related waves in the visual system during wakefulness.

Electrophysiological characterization of neurons in the dorsolateral pontine rapid-eye-movement sleep induction zone of the rat: Intrinsic membrane properties and responses to carbachol and orexins

“…Their inhibition by acetylcholine during REM sleep will de-inactivate their low-threshold calcium current and allow them to fire single spikes or a burst of action potentials when receiving excitatory input, which may originate from long-lead PGO related neurons in the dorsal mPRF (McCarley and Ito, 1983;Pare et al, 1990) and/or the caudoventral pontine tegmentum (Vanni-Mercier and Debilly, 1998). In the cat, PGO burst neurons with a short lead time (< 100 ms) prior to P-waves have been recorded in the parabrachial region which borders and overlaps with the subcoeruleus area recorded in this study in the rat (McCarley et al, 1978;Sakai and Jouvet, 1980;Nelson et al, 1983;Steriade et al, 1990;Datta and Hobson, 1994). Although neurons with these properties have also been recorded in other areas of the brainstem reticular formation, they seem to be particularly concentrated in the SubC area, which is consistent with this area being the best site to record P-waves Farber et al, 1980;Kaufman and Morrison, 1981) and the most sensitive site for carbachol to cause an enhancement of P-wave frequency (Datta et al, 1998).…”

From synapse to gene product: prolonged expression of c-fos induced by a single microinjection of carbachol in the pontomesencephalic tegmentum

“…PGO pontine pathways project through the tegmentum and communicate with the L/MVN, providing evidence, as do our results, of involvement of the vestibular system in the generation of PGO waves [58]. Additionally, there is agreement from physiological, pharmacological, and lesion studies that PGO-on neurons in the pontine tegmentum are considered to be the final transferring output components of the PGO generator network [15,60,85]. This is a relevant point, since even dramatic conditions such as labyrinthectomy, that significantly changes the spontaneous firing rate of L/MVN neurons, do not modify c-fos expression in the L/MVN [12], whereas we find that LTPE does.…”

Human brain activity time-locked to rapid eye movements during REM sleep

“…Furthermore, the temporal relation of PGO waves to REMs across species is also not clear yet. That is, whereas REMs are highly correlated with PGO-waves in the cat (Nelson et al 1983;Datta and Hobson 1994), PGO-waves in humans are incompletely associated with REMs (Lim et al 2007). The present study emphasizes that further research will be needed to more fully understand the functional neuroanatomy of PGO waves and REMs across species.…”