New bands in the sleep stages of spider monkeys (Ateles geoffroyi): Electroencephalographic correlations and spatial distribution.

The study of electroencephalographic (EEG) signals in nonhuman primates has led to important discoveries in neurophysiology and sleep behavior. Several studies have analyzed digital EEG data from primate species with prehensile tails, like the spider monkey, and principal component analysis has led to the identification of new EEG bands and their spatial distribution during sleep and wakefulness in these monkeys. However, the spatial location of the EEG correlations of these new bands during the sleep-wake cycle in the spider monkey has not yet been explored. Thus, the objective of this study was to determine the spatial distribution of EEG correlations in the new bands during wakefulness, rapid eye movement (REM) sleep, and non-REM sleep in this species. EEG signals were obtained from the scalp of six monkeys housed in experimental conditions in a laboratory setting. Regarding the 1-21 Hz band, a significant correlation between left frontal and central regions was recorded during non-REM 2 sleep. In the REM sleep, a significant correlation between these cortical areas was seen in two bands: 1-3 and 3-13 Hz. This reflects a modification of the degree of coupling between the cortical areas studied, associated with the distinct stages of sleep. The intrahemispheric EEG correlation found between left perceptual and motor regions during sleep in the spider monkey could indicate activation of a neural circuit for the processing of environmental information that plays a critical role in monitoring the danger of nocturnal predation.

Emotional facial expressions during REM sleep dreams.

Although motor activity is actively inhibited during rapid eye movement (REM) sleep, specific activations of the facial mimetic musculature have been observed during this stage, which may be associated with greater emotional dream mentation. Nevertheless, no specific biomarker of emotional valence or arousal related to dream content has been identified to date. In order to explore the electromyographic (EMG) activity (voltage, number, density and duration) of the corrugator and zygomaticus major muscles during REM sleep and its association with emotional dream mentation, this study performed a series of experimental awakenings after observing EMG facial activations during REM sleep. The study was performed with 12 healthy female participants using an 8-hr nighttime sleep recording. Emotional tone was evaluated by five blinded judges and final valence and intensity scores were obtained. Emotions were mentioned in 80.4% of dream reports. The voltage, number, density and duration of facial muscle contractions were greater for the corrugator muscle than for the zygomaticus muscle, whereas high positive emotions predicted the number (R2 0.601, p = 0.0001) and voltage (R2 0.332, p = 0.005) of the zygomaticus. Our findings suggest that zygomaticus events were predictive of the experience of positive affect during REM sleep in healthy women.

Efecto de las crisis epilépticas parciales y generalizadas sobre la arquitectura del sueño en ratas / Effect of partial and generalised epileptic seizures on sleep architecture in rats

Introducción. La alteración del sueño producido por las crisis epilépticas se conoce; sin embargo, aún se tiene poca información de la alteración en el sueño por el tipo de crisis epiléptica. Materiales y métodos. Se evaluó la arquitectura del sueño de ratas en registros polisomnográficos de 36 horas tras inducirles crisis epilépticas parciales y generalizadas. Para la inducción de las crisis epilépticas se aplicaron in situ 50-100 UI de penicilina G sódica en la amígdala del lóbulo temporal. Resultados. Las crisis parciales y generalizadas provocaron el aumento en la latencia del sueño de ondas lentas (SOL) y sueño de movimiento oculares rápidos (MOR). El número de episodios de las fases de vigilia, SOL y sueño MOR disminuyó y la duración media de los episodios de la vigilia y del SOL aumentó, mientras que la del sueño MOR disminuyó. El porcentaje total del sueño MOR disminuyó significativamente. Durante el primer período de luz, las crisis parciales y generalizadas provocaron el incremento de la vigilia y la reducción de las fases del SOL y sueño MOR. En el período de oscuridad, aumentó el SOL, disminuyó la vigilia y no hubo cambios en el sueño MOR. En el segundo período de luz los porcentajes de las fases de vigilia y SOL regresaron a los valores control y el porcentaje del sueño MOR continuó disminuido. Conclusión. Los cambios en la organización del sueño dependen del tipo de crisis epiléptica que se presenta. Las crisis epilépticas generalizadas provocaron mayor deterioro en el sueño MOR (AU)

Introduction. It is a well-known fact that epileptic seizures disrupt sleep, yet little information is available about sleep disorders according to the type of epileptic seizures. Materials and methods. The sleep architecture of rats was evaluated in polysomnography recordings 36 hours after inducing partial and generalised epileptic seizures in them. The epileptic seizures were induced by applying 50-100 IU of sodium G penicillin in the amygdala of the temporal lobe. Results. Partial and generalised seizures triggered an increase in the latency of slow wave sleep (SWS) and rapid eye movement (REM) sleep. The number of episodes of the phases of wakefulness, SWS and REM sleep was reduced and the mean duration of the episodes of wakefulness and SWS increased, while that of REM sleep diminished. The total percentage of REM sleep diminished signifi cantly. During the first period of light the partial and generalised seizures triggered an increase in wakefulness and a reduction in the phases of SWS and REM sleep. In the period of darkness, the SWS increased and wakefulness decreased, while there were no changes in REM sleep. In the second period of light, the percentages of the phases of wakefulness and SWS returned to control values and the percentage of REM sleep continued to be reduced. Conclusions. Changes in the structuring of sleep depend on the type of epileptic seizure that presents. Generalised epileptic seizures caused greater deterioration in REM sleep (AU)

[Effect of partial and generalised epileptic seizures on sleep architecture in rats]. / Efecto de las crisis epilépticas parciales y generalizadas sobre la arquitectura del sueño en ratas.

INTRODUCTION: It is a well-known fact that epileptic seizures disrupt sleep, yet little information is available about sleep disorders according to the type of epileptic seizures. MATERIALS AND METHODS: The sleep architecture of rats was evaluated in polysomnography recordings 36 hours after inducing partial and generalised epileptic seizures in them. The epileptic seizures were induced by applying 50-100 IU of sodium G penicillin in the amygdala of the temporal lobe. RESULTS: Partial and generalised seizures triggered an increase in the latency of slow wave sleep (SWS) and rapid eye movement (REM) sleep. The number of episodes of the phases of wakefulness, SWS and REM sleep was reduced and the mean duration of the episodes of wakefulness and SWS increased, while that of REM sleep diminished. The total percentage of REM sleep diminished significantly. During the first period of light the partial and generalised seizures triggered an increase in wakefulness and a reduction in the phases of SWS and REM sleep. In the period of darkness, the SWS increased and wakefulness decreased, while there were no changes in REM sleep. In the second period of light, the percentages of the phases of wakefulness and SWS returned to control values and the percentage of REM sleep continued to be reduced. CONCLUSIONS: Changes in the structuring of sleep depend on the type of epileptic seizure that presents. Generalised epileptic seizures caused greater deterioration in REM sleep.

TITLE: Efecto de las crisis epilepticas parciales y generalizadas sobre la arquitectura del sueño en ratas.Introduccion. La alteracion del sueño producido por las crisis epilepticas se conoce; sin embargo, aun se tiene poca informacion de la alteracion en el sueño por el tipo de crisis epileptica. Materiales y metodos. Se evaluo la arquitectura del sueño de ratas en registros polisomnograficos de 36 horas tras inducirles crisis epilepticas parciales y generalizadas. Para la induccion de las crisis epilepticas se aplicaron in situ 50-100 UI de penicilina G sodica en la amigdala del lobulo temporal. Resultados. Las crisis parciales y generalizadas provocaron el aumento en la latencia del sueño de ondas lentas (SOL) y sueño de movimiento oculares rapidos (MOR). El numero de episodios de las fases de vigilia, SOL y sueño MOR disminuyo y la duracion media de los episodios de la vigilia y del SOL aumento, mientras que la del sueño MOR disminuyo. El porcentaje total del sueño MOR disminuyo significativamente. Durante el primer periodo de luz, las crisis parciales y generalizadas provocaron el incremento de la vigilia y la reduccion de las fases del SOL y sueño MOR. En el periodo de oscuridad, aumento el SOL, disminuyo la vigilia y no hubo cambios en el sueño MOR. En el segundo periodo de luz los porcentajes de las fases de vigilia y SOL regresaron a los valores control y el porcentaje del sueño MOR continuo disminuido. Conclusion. Los cambios en la organizacion del sueño dependen del tipo de crisis epileptica que se presenta. Las crisis epilepticas generalizadas provocaron mayor deterioro en el sueño MOR.