Functional activity and pH of the cerebral cortex

Abstract

SEVEN FIGUBESI n a previous paper by Brody aiid Dusser de Rarenne ( ' 3 2 ) it was established that tlie motor respoiise to electrical stimulation of tlie cortex of tlie cat mas markedly enhanced during hyperventilation of the animal. Following electrical stimulation of the cortex Dusser de Bareiine and l\lcCulloch ( '34, '37) found a few years ago a temporary inactivation of the cortex, extinction, which under special types of stimulation, lasts for several minutes. It was considered highly probable that among the factors underlying these changes in excitability were changes in the pH of tlie cortex. In a recent preliminary paper (Dusser de Rsreiine et al., '37) a method has heen briefly described, showing that it is possible to measure the pH of the cerebral cortex. I n this paper we wish to report more fully on the relations of the pH of the cortex to its activity and excitability under various experiniental coiiditioiis including electrical stimulation. METHODSThe method used gives a continuous record of the pH of the cortex, its D.C. potentials, the respiration of the animal (natural or artificial), time a n d signals. This is done by photographing upon moving paper a screen ( fig. 1, S)

Roles of anoxia and noise-induced hearing loss in the postictal refractory period for audiogenic seizures in mice.

“…One must also consider the possible influence of acid-base imbalance, which may be associated with anoxia during seizures, since this could affect neuronal excitability (cf. Dusser de Barenne, McCullock, & Nims, 1937;Jasper & Erickson, 1941).…”

Roles of anoxia and noise-induced hearing loss in the postictal refractory period for audiogenic seizures in mice.

“…One must also consider the possible influence of acid-base imbalance, which may be associated with anoxia during seizures, since this could affect neuronal excitability (cf. Dusser de Barenne, McCullock, & Nims, 1937;Jasper & Erickson, 1941).…”

Level of autonomic activity and electroencephalogram.

“…If this ip per sec, autonomic rhythm is supplied along with the sympathetic impulses to the cerebral blood vessels, it unquestionably could contribute to the alpha rhythm. This would provide an important additional mechanism contributing to the association of alpha potential with cerebral vasoconstrictor tone (30)(31)(32)(33)(34)(35)(36)(37)(38).…”

Roles of anoxia and noise-induced hearing loss in the postictal refractory period for audiogenic seizures in mice.

“…One must also consider the possible influence of acid-base imbalance, which may be associated with anoxia during seizures, since this could affect neuronal excitability (cf. Dusser de Barenne, McCullock, & Nims, 1937;Jasper & Erickson, 1941).…”

Level of autonomic activity and electroencephalogram.

“…If this ip per sec, autonomic rhythm is supplied along with the sympathetic impulses to the cerebral blood vessels, it unquestionably could contribute to the alpha rhythm. This would provide an important additional mechanism contributing to the association of alpha potential with cerebral vasoconstrictor tone (30)(31)(32)(33)(34)(35)(36)(37)(38).…”

Roles of anoxia and noise-induced hearing loss in the postictal refractory period for audiogenic seizures in mice.

“…One must also consider the possible influence of acid-base imbalance, which may be associated with anoxia during seizures, since this could affect neuronal excitability (cf. Dusser de Barenne, McCullock, & Nims, 1937;Jasper & Erickson, 1941).…”

Level of autonomic activity and electroencephalogram.

“…If this ip per sec, autonomic rhythm is supplied along with the sympathetic impulses to the cerebral blood vessels, it unquestionably could contribute to the alpha rhythm. This would provide an important additional mechanism contributing to the association of alpha potential with cerebral vasoconstrictor tone (30)(31)(32)(33)(34)(35)(36)(37)(38).…”