Tonotopic bands produced by tones commenced long after 2-deoxyglucose injection.

Presentation of two different tones at two different time periods each under two different types (14C or 3H) of 2-deoxyglucose (2-DG) produced two bands of labelling in the inferior colliculus (IC) of a guinea pig. Filtering tests revealed that both bands were produced by only one of the labels (14C). Four guinea pigs were given one injection of 2-DG and then stimulated with two tones, each presented at different time periods. Two bands of labelling were produced in IC, with one band being produced by tones given 55-90 min after injection. The implications of this long lasting effect of 2-DG are discussed for the general 2-DG model and for sequential double labelling experiments.