This paper describes how an adult zebrafish can be immobilized, intubated, and used for in vivo electrophysiological experiments to allow recordings and manipulation of neural activity in an intact animal.
Johnston, L., Ball, R. E., Acuff, S., Gaudet, J., Sornborger, A., Lauderdale, J. D. Electrophysiological Recording in the Brain of Intact Adult Zebrafish. J. Vis. Exp. (81), e51065, doi:10.3791/51065 (2013).