Habituation of Responses Recorded in the Reticular Formation: The Possible Involvement of Opiates
The amplitude of a response can decrease or even disappear upon repeated stimulation. This change is known as habituation and is a form of learning. Cells in the reticular formation of an intact frog tend to habituate to repeated peripheral stimuli. In decerebrate frogs this is not the case. Electrical stimuli of 0.2 msec. duration were applied every 5 sec. to the skin surface at intensity 1.25 × threshold. Potentials evoked were recorded using monopolar glass capillary microelectrodes of low resistance and filled with 4M NaCl. The recordings were made in the reticular formation of the medulla oblongata, 0.5mm lateral to the midline, 1.5mm rostral to the obex.