Table 1.

Generalized Linear Mixed Effects Models (GLMM) of performance measures on the Cylinder and Barrier tasks. Non-significant interactions (NS) were removed from models prior to determining the test statistic.

modelexplanatory variablesBaseline Worm latencyReward Worm latencyPecks
1(a) Opaque versus transparentX2 = 2.92, p = 0.09X2 = 72.61, p < 0.01X2 = 549.07, p < 0.01
1(b) Task (Cylinder)X2 = −0.06, p = 0.79X2 = −372.56, p < 0.01X2 = −82.91, p < 0.01
1(c) Improvement across trialsX2 = −10.47, p = 0.01X2 = −97.10, p < 0.01X2 = −69.37, p < 0.01
2(a) Experience (yes)X2 = −8.26, p = 0.004X2 = −27.86, p < 0.001X2 = −14.74, p = 0.0001
3(a) PersistenceX2 = −1.33, p = 0.25X2 = 0.65, p = 0.42X2 = 8.58, p = 0.003
3(b) Dietary breadthX2 = −1.50, p = 0.22X2 = 1.27, p = 0.26X2 = 5.62, p = 0.018
3(c) Body ConditionX2 = −0.01, p = 0.92X2 = 0.91, p = 0.34X2 = −0.02, p = 0.90
3(d) Sex (male)X2 = 1.11, p = 0.29X2 = −3.08, p = 0.08X2 = −0.21, p = 0.65
3(e) Sex (male) * Body Conditionn.s.n.s.n.s.