(1990b) used a version of the radial search task (Foreman et al.
Subjects do seem to recognize intuitively that they use separate strategies in performing a differentially-rewarded radial search task; they will articulate the fact that they have to (a) remember which locations are rewarded, and (b) remember which they have previously visited on that particular trial (Foreman, Foreman, Cummings & Owens, 1990a), though it is, of course, unrealistic to expect intuitive awareness of the degree to which one fuels the other.
One way of examining the relative independence of these two measures or components of memory is to examine, for each separately, the effects of manipulations known to affect overall radial search performance.
We used a group of subjects who had reached an age (six years) at which they are competent on the radial search task in terms of both ATM and WTM (Foreman et al., 1990b).
Choice patterning is seen in the differentially rewarded version of the radial search task (Foreman et al., 1990b), though in this study it was rare to have t remind children more than once to desist from adjacent location response patterns.
(1990a), and emphasizes once again the importance of autonomous spatial choice in the development of radial search performance.
The improvement of radial search performance that occurs between age two and six years (Foreman et al., 1990b) overlaps with a period of rapid development in recognition memory, documented for the two- to three-year period by Daehler & Bukatko (1977) using a selective attention to novelty paradigm.
Moreover, the calculation in Appendix 1 assumes sampling with replacement, although even naive subjects in radial search tasks (both animal and human) tend to choose with certain constraints, for example almost never returning to a location that was visited on the previous choice (Eckerman 1980), an example of sampling with delayed replacement.