Y-maze behavior after an analog of ACTH 4--9, evidence for an attentional alteration.

Adult, male, Swiss-Webster mice were injected with either control solution or various doses of a long-acting analog of ACTH 4--9. The drug produced significant alterations in performance in an equiangular Y-maze. In comparison with control performance, both 25 and 50 micrograms/kg of drug produced a significant increase in repeated two-arm entries. This response pattern is consistent with the hypothesis that the drug produced a focusing of attention.