The spots were presented either alone or time-locked with the rapid movement of a large, high contrast peripheral pattern, referred to as shift. In experiments with human observers the task was to indicate, by a keypress, whichof two otherwise identical temporal intervals contained the spot. The shift also reduces the sensitivity of human observers to the same target. This suggests that the LGN is a potential locus for the modulation of visual responses that leads to saccadic suppression. Effects of Volatile Anaesthetics on the Membrane Potential and Ion Channels of Cultured Neocortical Astrocytes.
Volatile anaesthetics cause changes in the resting membrane potential of central neurons.
This effect probably arises from actions on neuronal ion channels, but may also involve alterations in the ion composition of the extracellular space. Since glial cells play a key role in regulating the extracellular ion composition in the brains of mammals, we analyzed the effects of halothane, isoflurane, and enflurane on the membrane conductances and ion channels of cultured cortical astrocytes. We further studied the effects of halothane and enflurane on single ion channels in excised membrane patches. At higher concentrations, effects of enflurane and halothane, but not of isoflurane, were statistically significant. Single-channel recordings revealed that halothane and enflurane activated a high conductance anion channel, which possibly mediated the effects observed during whole cell recordings.