This chapter focuses on the expression of voltage-gated and ligand-gated ion channels in the cortical and thalamic circuitry and their modulation with general anesthetics. It draws on the subclass of voltage-gated calcium channels that play a crucial role in neuronal oscillation. The chapter discusses long-term plasticity of the channels in the thalamus that can contribute to the neurotoxic effects of general anesthetics in the developing brain. In contrast to the superfamily of voltage-gated ion channels, the proteins are not sensitive to voltage but are activated upon the binding of specific ligands that are typically released during synaptic activity. Voltage-gated calcium channels, which are heteromeric complexes found in the plasma membrane of virtually all cell types, show a high level of electrophysiological and pharmacological diversity. T-channels are new considerations in anesthesia research, but the part they play in pain transmission and the neuronal sleep pathway make them important targets for further exploration.