Locations nearby in space are typically experienced together in time: Spatial and temporal contiguity are confounded. In these experiments, subjects learned a map under controlled temporal order. In Experiment 1, one condition allowed the natural confound between space and time. Another condition did not; spatially near and far locations were temporally distant. A spatial priming effect was found in the former but not the latter condition. In Experiment 2, two groups learned a map in an unconfounded condition. For one group, temporal proximity in the learning order was held constant and distant, as in Experiment 1. For the other group, temporal proximity was held constant and close. Neither group showed a spatial priming effect. Experiment 3 replicated the unconfounded acquisition of Experiment 1, but tested for temporal priming, which was found. These results are difficult to reconcile with any theory of map representation that has metric properties that emerge independent of the temporal conditions of acquisition.A brief version of Experiment 1 was presented at the 30th annual meeting of the Psychonomic Society, Atlanta, November, 1989. We thank Tim McNamara for his helpful comments throughout the conduct of this research, for giving us access to his map material, and for his comments on earlier drafts. We also thank anonymous reviewers for their comments on an earlier draft, and Jacquelyn Joseph and Stacey Donegan for their help in conducting the research.

Forty groups of subjects were given six lists of 25 nouns each for immediate free written recall. A measure of free recall was thereby obtained for each of 900 nouns in the Paivio, Yuille, and Madigan (1968) norms, each noun's measure based on the recall of 32 subjects. First-order correlations showed recall to be correlated with imagery, concreteness, meaningfulness, Thorndike-Lorge frequency, and Kucera-Francis frequency. Partial correlations showed meaningfulness to be essentially unrelated to recall and concreteness only moderately related. In contrast to previous comparisons, which were based on smaller ranges of frequency and were more susceptible to list-specific effects, imagery and frequency were found to be approximately equal in their influence on free recall.Presented with this report are measures of free recall for 900 of the 925 English nouns in the Paivio, Yuille, and Madigan (1968) norms. Several considerations led us to obtain these measures. The first was the general issue of which particular attributes of words affect free recall. It is well established in the Paivio et al. data that attributes suspected to influence recall are themselves correlated. Thus, if a relationship between a variable and recall performance is observed, it is important to establish that the effect is not due to contamination by other variables. Considerable effort has been spent along these lines and the influence of rated imagery on free recall seems firmly established (Postman, 1975). However, there are some recent complications with this picture (Richardson 1975a(Richardson , 1975b, and the roles of rated meaningfulness and frequency remain ambiguous. A second consideration was the issue of which variable has the greater influence on recall. Since Paivio's (l971) review there has been an increased acceptance of the view that rated imagery is more influential than meaningfulness and frequency. However, in contrast to the weight of evidence implicating the effect of rated imagery on free recall, the claim that imagery is more influential than frequency and meaningfulness is based on very few studies.Two more immediate concerns compelled the collection of these measures. The first was the outcome of an experiment by Warren (1977), who examined the effect of a pursuit-rotor task on recall by subjectsThe authors thank Patti Craig, Rena Dreskin, and Paige Highfield, who not only helped collect data, but also contributed to the research at other stages. We also thank M. Frank Evarts for his help with the unpublished study described in the introduction. Requests for reprints should be sent to Keith Clayton, 134 Wesley Hall, Department of Psychology, Vanderbilt University, Nashville, Tennessee 37240. engaged in recall and tracking concurrently. In two experiments Warren found that the recall-eoncurrent task interfered with picture recall but not word recall. This is consistent with the view that a concurrent tracking task interferes with, or suppresses, imagery during recall. If this is so, and if the superior recall of con...

In four experiments, we explored constraints on priming in spatial memory. In Experiments 1 and 2, subjects who were familiar with the locations of buildings on the Vanderbilt campus participated in a recognition test. The subjects' task was to decide whether or not named buildings were on the campus. Foils in this recognition test were realistic but fictional names of buildings. In principle, the subjects could have performed this task without using spatial knowledge; in fact, they must not have used spatial knowledge, because there was no evidence of priming in recognition as a function of the spatial relations between buildings on the campus. This result differs from those obtained in earlier experiments that have examined memory of spatial layouts learned in laboratory settings. In Experiment 3, the fictional foils were replaced by names of buildings in an area of the campus separated geographically from the main campus. Evidently, this change induced subjects to retrieve spatial knowledge, because the spatial priming effect materialized. A fourth experiment replicated the above findings in a single experiment and demonstrated that spatial priming could be obtained when the configuration of buildings was learned experimentally. These results are explained by appealing to the "decontextualization" that takes place in memory over time.

The observation that natural curves and surfaces are often fractal suggests that people may be sensitive to their statistical properties. The perceptual protocols that underlie discrimination between fractals and between other types of random contour and fractals are examined. Discrimination algorithms that have precisely the same sensitivities as human observers are constructed. These algorithms do not recognize the integrated scale hierarchy intrinsic to fractal form and operate by imposing a metatheory of structure that is based on a signal-noise distinction. The success of the algorithms implies that (a) self-affinity in random fractals is not perceptually recovered and (b) people have a natural disposition to view contour in terms of signal and noise. The authors propose that this disposition be understood as a principle of perceptual organization.

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