Fig. 5.

Experiment 1B. Postlesion CTA acquisition is shown, with the CS being 0.3 M alanine. A: controls (n = 8) and all LHx, n = 18. B: performance by lesions subgroups: double (dLHx; n = 6), aLHx (n = 6), pLHx (n = 6), and Con. After the initial pairing with LiCl, the Con intake dropped to near zero (trial 2) and remained there in subsequent trials. On trial 2, the combined LHx intake (A) also dropped significantly but only by about a third (63%). In the remaining two 1B trials (trials 3 and 4), the LHx rats maintained their intake above 40% of their initial CS consumption with the pLHx subgroup highest and the aLHx group lowest (B) Even in trial 5, when they had a choice between the CS and water, the LHx animals ingested 39% as much CS as on trial 1. CS, conditioned stimulus, 0.3 M alanine; P, CS intake paired with LiCl; NP, no LiCl administered.