Figure 7. Differences in mean absolute activity are found in mutants with defects in exploration or habituation.

The 〈|ΔD|〉 of four genotypes: Canton-S, norpA⁷, rut²⁰⁸⁰ and krz¹, along the boundary of a circular arena of radius 4.2 cm are shown. For all the four genotypes, 〈|ΔD|〉 are plotted as a function of time and arena coverage in panels A and B, respectively. For visualization purposes, 21 time points are shown. The interval between any two consecutive time points in the plots is 30 seconds. norpA⁷, rut²⁰⁸⁰ and krz¹, which are known to have exploratory or habituation defects, display different patterns of mean absolute activity from Canton-S flies. Coverage had the least effect in the decay of 〈|ΔD|〉 in the blind norpA⁷ flies, consistent with a role of visual learning in habituation. The krz¹ flies show a low initial ambulation which decreases rapidly to a stable state before habituation could occur, consistent with a reduced motivation to respond to novelty. The decay in rut²⁰⁸⁰ lies between non-habituating blind norpA⁷ and wild type Canton-S flies.