Reticular potentials evoked by electrical stimulation of individual semicircular canals.

Responses of pontine reticular formation neurons following single shock electrical stimulation of single semicircular canals were recorded with tungsten microelectrodes in 40 curarized guinea-pigs. The field and unitary potentials obtained from 62 reticular sites, exhibited latency values ranging from 0.3 to 2.5 msec. The early latencies (0.3-0.5 msec) have been interpreted as responses mediated by primary vestibular fibres projecting directly to the reticular substance.     

Electroencephalogram potentials evoked by hemi-retinal stimulation

Zusammenfassung Als Reaktion auf Reizung der lateralen Gesichtsfeldhälfte wurden evozierte Potentiale der Hirnrinde des Menschen registriert. Reizung der einen Gesichtshälfte erzeugte frühzeitig ein Maximum der Potentiale der gegenseitigen Hemisphäre sowie Phasenumkehr der Potentiale der gleichseitigen Hemisphäre.     

Nystagmus evoked in the rabbit by electrical stimulation of the lateral geniculate body

Résumé La stimulation électrique du corps géniculé latéral et de la radiation optique provoque des mouvements nystagmiques contraversifs. Cette réponse est inhibée fortement par l'illumination de l'il ipsilatéral.     

Post-tetanic changes of bilateral dorsal root potentials evoked by stimulation of the cutaneous afferents

Summary In spinal cats following tetanic stimulation of the cutaneous nerve bilateral dorsal root potentials in the lumbar spinal cord are depressed. Because of differences between ipsi- and contralateral potentials, this depression can usually be evoked only on one side of the cord.     

Reflex motility of the stomach evoked by electrical stimulation of the hepatic vagus nerve

Summary Electrical stimulation of the cranial end of the cut hepatic branch of the vagus nerve produced an increase in the motility of the empty stomach in the rat, whereas systemic injection of insulin produced a gradual increase in the motility.Acknowledgment. The authors are indebted to Dr K. Yamaguchi and Prof. A. Niijima for their encouragement of the project.     

Post-tetanic changes of bilateral dorsal root potentials evoked by stimulation of the cutaneous afferents.

In spinal cats following tetanic stimulation of the cutaneous nerve bilateral dorsal root potentials in the lumbar spinal cord are depressed. Because of differences between ipsi- and contralateral potentials, this depression can usually be evoked only on one side of the cord.     

Extraprimary cortical evoked potentials in freely moving cat following photic stimulation

Zusammenfassung Die extraprimären optischen Potentiale, die in der somatosensorischen, akustischen und Assoziationsrinde der wachen Katzen mittels chronischer epiduraler Elektroden registriert wurden, zeigen fast dieselbe Latenz wie die primären Potentiale, unterscheiden sich aber von ihnen durch ihre Form.     

Nystagmus evoked by intermittent photic stimulation of the rabbit's eye

Zusammenfassung Monokuläre Reizung des Kaninchens durch Lichtblitze ruft einen Nystagmus hervor, dessen Richtung identisch ist mit der Richtung der Augenbewegungen, die durch elektrische Stimulierung des ipsilateralen Nervus opticus verursacht werden. Die anhaltende Beleuchtung des kontralateralen Auges hemmt die Nystagmusreaktion.

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The authors wish to thank the Joseph Porton Trust for their generous support of this work. They are indobted to Mr.R. Knafo for preparation of the drawings.     

Oculomotor reflex evoked by vibrassae stimulation in the cat]

The oculomotor effects of vibrissae stimulation have been studied in the "encéphale isolé" non-anaesthetized Cat. Intracellular recording of lateral rectus motoneurones showed an excitatory projection via the ipsilateral infraorbital nerve to these motoneurones. The afferent fibers are type A alpha, recuited with a low threshold (0.2-0.5 mA) and convey information about vibrissae displacement.     

Modulation during sleep of the spino-cerebellar evoked potentials

Riassunto Nel sonno desincronizzato si osserva una depressione fasica delle risposte cerebellari evocate dalla stimolazione di nervi dell'arto posteriore. Questa depressione ipnica della risposta spinale cerebellare è completa durante i REM, ma si manifesta, sia pure parzialmente, durante i movimenti oculari isolati che compaiono negli Intervalli tra i tipici REM.

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This investigation was supported by PHS research grant No. NB-02990-05 from the National Institute of Neurological Diseases and Blindness, N.I.H., Public Health Service (USA).     

Responses evoked by stimulation of the acoustic pathway during the sleep-wakefulness cycle

Riassunto Lo studio delle risposte evocate nelle radiazioni acustiche e nelle arec acustiche primarie da stimolazione delle vie uditive centrali dimostra che: (a) la trasmissione degli impulsi ascendenti a livello del corpo genicolato mediale è facilitata sia durante il sonno profondo che al risveglio mentre, (b) l'eccitabilità corticale è maggiore durante il sonno leggero.

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Part of these results has been presented at a meeting of the Società italiana di Biologia sperimentale, held in Genova on July 30, 1964.     

Foraging behaviour patterns of herring gulls elicited by electrical forebrain stimulation

Zusammenfassung Zwei artspezitische Verhaltensabläufe, die Silbermöwen (Larus argentatus) bei der Futtersuche und Futteraufnahme zeigen, wurden durch elektrische Reizung begrenzter Bezirke des rostralen Vorderhirns experimentell hervorgerufen. Diese Befunde stützen vergleichend-anatomische Schlussfolgerungen über die funktionelle Rolle des rostralen Vorderhirns bei Vögeln.

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The work was supported by grants from the United States Air Force, the Science Research Council and the Royal Society to ProfessorN. Tinbergen and myself. It was partially carried out at the Department of Zoology, Oxford. The assistance of Dr.G. Thompson and Mr.A. Jackson is gratefully acknowledged.