Differential 2-deoxyglucose uptake into chick brain structures during passive avoidance training.

The pattern of [14C]2-deoxyglucose(-6-phosphate) accumulation in the brains of 14 chicks, 24 h post hatch was investigated. Isotope was injected 1 min prior to birds pecking either a water-coated or a methylanthranilate-coated bead (passive avoidance training). Birds were killed following testing for pecking or avoidance of a similar but dry bead 30 min later. Autoradiograms of coronal and parasaggital brain sections were scanned densitometrically and uptake into 12 identified and relatively heavily labelled structures measured. Three of the structures, hyperstriatum ventrale (posterior), palaeostriatum augmentatum and lobus parolfactorius showed significantly enhanced labelling (by 10, 13 and 11%; p less than 0.001, less than 0.05 and less than 0.05 respectively) in the birds which had been trained on the methylanthranilate bead by comparison with those which had pecked at the water-coated bead. The results are discussed in relationship to other observed biochemical changes consequent on passive avoidance training.