Sleep in the moles, Scalopus aquaticus and Condylura cristata

doi:10.1016/0014-4886(70)90117-2

Experimental Neurology

Volume 27, Issue 3, June 1970, Pages 564-578

https://doi.org/10.1016/0014-4886(70)90117-2 Get rights and content

Abstract

Polygraphic manifestations of waking and sleep were studied in six Eastern moles (Scalopus aquaticus) and one star-nosed mole (Condylura cristata). Recordings were made, over periods of 24 or 72 hr, from electrodes chronically implanted in neocortex, hippocampus, neck muscles, and chest wall. Small thermistor beads recorded brain temperature. Five EEG states were distinguished; waking, drowsy, spindle sleep, slow wave sleep, and paradoxical sleep (PS). Sleep accounted for 35.2% of total recording time; PS occupied 25.0% of total sleep time. During sleep PS recurred at an interval of 10.4 min. With a few exceptions possibly related to the mole's underground life, the physiological characteristics of both phases of sleep are typically mammalian. The PS was characterized by neocortical desynchronization, prominent hippocampal theta activity, irregular respiration, brain temperature increase, and myoclonic jerking on a background of neck muscle atonia. The normal appearance and large amounts of PS in this blind or nearly-blind mammal suggest there is no fundamental relationship between PS and visual system functioning.

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AYALA-GUERRERO, F., L. VARGAS-REYNA, J. L. RAMOS AND G. MEXICANO. Sleep patterns of the volcano mouse (Neotomodon alstoni alstoni). PHYSIOL BEHAV 64(4) 577–580, 1998.—Sleep-waking patterns of the volcano mouse were studied under laboratory conditions. This rodent exhibits four states of vigilance: active wakefulness (Aw), quiet wakefulness (Qw), slow-wave sleep (SWS), and paradoxical (PS), or rapid-eye movement (REM) sleep. These states present, in general, the classic mammalian electrophysiological patterns. Although sleep periods were distributed at any time of the nychthemeral cycle, they showed the tendency to concentrate between 0800 and 2000 hours. The volcano mouse may be considered as a “good” sleeper, because it shows a relatively high percentage of sleep from the total recording time (TRT). Slow-wave sleep occupied 64.54 ± 8.84% (mean ± SD) of the total recording time, while 7.56 ± 1.31% corresponded to rapid-eye movement sleep. The average duration of the rapid-eye movement sleep phase was 126.48 ± 17.79 s, exhibiting an average recurrence of 49 ± 9.28 phases throughout the nychthemeral cycle. Mean duration of the sleep cycle was 9.23 ± 2.36 min. Quantitative data of the volcano mouse sleep may be considered adequate for its body size and characteristic of an animal which sleeps in secure places under free-living conditions.

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¹: Supported by USPHS Grant MH-05286 and by the Veterans Administration. We thank P. Van Twyver, W. R. Goff, D. Cicchetti, T. Fusco, and R. Poindexter for advice and assistance. A preliminary account of this study has been given (2). Dr. Van Twyver is a Veterans Administration Research Associate in Psychology.

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Sleep in the moles, Scalopus aquaticus and Condylura cristata

Abstract

Exp. Neurol.

Life Sci. PI

Electroencephalogr. Clin. Neurophysiol.

Exp. Neurol.

Electroencephalogr. Clin. Neurophysiol.

Exp. Neurol.

Brain Res.

Electroencephalogr. Clin. Neurophysiol.

Sleep in a primitive mammal, the spiny anteater

Psychophysiology

Notes from Underground: Sleep in the Moles, Scalopus aquaticus and Condylura cristata

Étude des structures cytoarchitectoniques du diencéphale de Talpa europaea (Insectivora talpidae)

Acta Anat.

Oculomotor control: A possible function of REM sleep

Psychol. Rev.

L'electroencephalogramme du sommeil chez les cercopithecinae: Erythrocebus patas et Cercopithecus aethiops sabaeus

Folia Primat.

Morfologia degli organi della vista negli insecttivori

Arch. Ital. Anat. Embriol.

Behaviour of the mole (Scalopus) and the shrew (Blarina)

J. Mammal.

The influence of the laboratory situation on the dreams of the experimental subject

J. Nerv. Ment. Dis.

Rapid eye movement sleep and cortical homeostasis

Psychol. Rev.

Vergleichend-anatomische Studien über das Gehirn des Maulwurfs

Morphol. Jahrb.

A comparative study of the osteology and myology of the cranial and cervical regions of the shrew, Blarina brevicauda, and the mole, Scalopus aquaticus

Misc. Pub. Mus. Zool. Univ. Mich.