Notes on Abnormal Electroencephalograms in the Telencephalon of the Chicken and Pigeon

Abstract

In a forthcoming paper, the author has previously described the EEG recorded from the Wulst of adult hens during wakefulness and sleep. For the purpose of comparison with normal EEGs, abnormal electrical activities are recorded from the same site (the Wulst) of adult hens under curarized and light anesthetic conditions, respectively. "Spontaneous" paroxysmal discharges, including the spike and wave complexes, are observed on the Wulst during extremely light anesthesia. Strychnine and penicillin spikes were found to occur on the Wulst. Spreading EEG depression can be readily induced by application of mechanical or chemical (25% KC1) stimulus in hens curarized with Fraxidil. Furthermore, a review has been made of abnormal EEGs which were induced by a kind of central nervous disorder with nutritional deficiency, environmental correlations and pharmacologic agents. Papers concerning Leao's spreading depression in the bird's brain are also included. The possibility of eliciting some important patterns of epileptic waves in the bird's telencephalon is emphasized.

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

“…body weight) of strychnine nitrate in both curarized and non-curarized adult hens (Ookawa, 1973c,d). The effect of systemically applied strychnine on behavior and cerebral EEG of the chicken still remains to be determined (Ookawa, 1973a). The present experiment demonstrated that strychnine spikes in the Wulst EEG can be induced by intraperitoneal injection in young and adult chickens.…”

Behavioral and Electroencephalographic Manifestations of Avian Epilepsy: A Review of the Literature

“…8), but they spread sometimes at a much higher rate than SD even to distant points of the hemisphere. The occurrence of paroxysmal discharges increased with repeated waves of SD (see also Ookawa, 1973a). It is interesting to note that Shibata et al (1973) have recently recorded reverberating SD around circular lesions in the pigeon striatum (see also Shibata, 1974), although the incidence of reverberating SD in the pigeon forebrain is considerably lower than in the rat cerebral cortex (Shibata and Bures, 1972).…”

“…In a previous paper (Ookawa, 1973a), the possibility of eliciting some important patterns of epileptic waves in the avian telencephalon was emphasized. The present review is an attempt to obtain further information on the behavioral and electrophysiological manifestations of epilepsy in birds.…”