Avian Wakefulness and Sleep on the Basis of Recent Electroencephalographic Observations

Ookawa, Takanori

doi:10.3382/ps.0511565

Cited by 39 publications

(15 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…First, the evidence shows that sleep-like states predominate (Peters et al 1965;Ookawa 1972;Corner et al 1973a;Speciale et al 1976;Bakhuis and van de Nes 1979;Bakhuis and Bour 1980). Second, the short periods of pre-hatching EEG activity described by some as 'wakefulness' (Ookawa 1972;Corner et al 1973a;Bakhuis and van de Nes 1979;Bakhuis and Bour 1980) in fact could not be distinguished from similar EEG patterns that are present during REM sleep. This is because the depressed muscle tone, presence of eye movements and autonomic instability (including irregular heart and breathing rates), which are all integral to REM sleep (Rattenborg et al 2000), were not measured in most studies.…”

Section: Discussionmentioning

confidence: 95%

Birth and hatching: Key events in the onset of awareness in the lamb and chick

Mellor¹,

Diesch²

2007

New Zealand Veterinary Journal

View full text Add to dashboard Cite

The neuroanatomical and neurophysiological development of the embryo and fetus and unique features of the physiological environment of the fetal brain, features which are lost at birth, support recent conclusions that under normal circumstances awareness (or consciousness) is probably not exhibited by the ovine embryo-fetus before birth and that it appears for the first time only after birth. However, there has apparently been no evaluation of whether or not similar mechanisms modulate awareness-related functions in domestic chicks before and after hatching. This comparative review, in seeking to rectify this, arrived at the following conclusions. First, the neural apparatus of both lambs and chicks appears to be too immature to support any states resembling awareness during at least the first half of pregnancy or incubation. Second, electroencephalographic (EEG) activity, which evolves subsequently, shows that states of sleep-like unconsciousness are likely to be continuously present in lambs until after birth, and that such states at least predominate in chicks until after hatching. Third, as in fetal lambs, epochs of so-called 'wakefulness' previously reported in chick embryos do not seem likely to represent short periods of awareness in ovo. Fourth, several neurosuppressive mechanisms, with some unique features, also operate or have the potential to operate in chicks before hatching, but a dearth of published information currently hinders a full comparison with those demonstrated to operate in fetal lambs. Fifth, contradicting the intuitive perception that vocalisation pre-hatching by the chick indicates the presence of awareness, published evidence suggests that vocalisation before and during hatching occurs mostly during EEG states indicating sleep-like unconsciousness. Sixth, as seems to be the case for newborn lambs after birth, it is possible that demonstrable awareness may appear for the first time only after hatching in chicks, presumably through waning neurosuppression and burgeoning neuroactivation, but such awareness seems to take longer to manifest itself. However, additional research in chicks is recommended to further assess this suggestion. Particular attention should be given to the status of vocal interactions between hen and chick which begin several days before hatching, and to the operation of neurosuppressive and neuroactivating mechanisms throughout the last 40% of incubation and during and after hatching.

show abstract

Section: Discussionmentioning

confidence: 95%

Birth and hatching: Key events in the onset of awareness in the lamb and chick

Mellor¹,

Diesch²

2007

New Zealand Veterinary Journal

View full text Add to dashboard Cite

show abstract

“…The influence of strychnine on polygraphic recordings was investigated in the remaining 20 chicks and 4 adult hens under unanethetized, restrained conditions. The EEG recording techniques and the recording site have been described fully in earlier papers (Ookawa, 1972(Ookawa, , 1973c. Before restraint, the trachea was cannulated and the bird fixed with a stereotaxic apparatus.…”

Section: Methodsmentioning

confidence: 99%

Effect of Strychnine on the Wulst EEG of Conscious Young and Adult Chickens

Ookawa

1974

Poultry Science

Self Cite

View full text Add to dashboard Cite

show abstract

“…The surface of the exposed frontal and parietal bones were slightly scraped with a spoonedged spatula, and carefully wiped off. Subsequently, a selected point (Ookawa, 1972), 3mm. from the midline and 4 mm.…”

Section: Methodsmentioning

confidence: 99%

Effect of Intravenously Administered Strychnine on the Wulst EEG of Conscious Adult Chickens

Ookawa

1973

Poultry Science

Self Cite

View full text Add to dashboard Cite

The influence of strychnine on behavior and on the Wulst EGG has been studied in conscious adult hens. Marked changes in behavior were not induced by 0.1 mg./kg. strychnine, but convulsions were produced by 0.5-5 mg./kg. strychnine in the adult hen. This demonstrated that threshold spiking in the EEG was shown with 1 mg./kg. intravenous dose of strychnine, and that strychnine spikes with large amplitude (1-2 mV.) could be induced by 2-5 mg./kg. intravenous doses of strychnine in conscious restrained hens as well as curarized adults. The present experiment indicated that the complete administration of high doses of strychnine into the blood stream is important for eliciting spikes in both conscious and curarized birds, and that artificial respiration is likewise important for the demonstration of strychnine spikes in the EEG of conscious hens.

show abstract

Avian Wakefulness and Sleep on the Basis of Recent Electroencephalographic Observations

Cited by 39 publications

References 42 publications

Birth and hatching: Key events in the onset of awareness in the lamb and chick

Birth and hatching: Key events in the onset of awareness in the lamb and chick

Effect of Strychnine on the Wulst EEG of Conscious Young and Adult Chickens

Effect of Intravenously Administered Strychnine on the Wulst EEG of Conscious Adult Chickens

Contact Info

Product

Resources

About