A variety of converging operations demonstrate key differences between separable dimensions, which can be analyzed independently, and integral dimensions, which are processed in a non-analytic fashion. A recent investigation of response time distributions, applying a set of logical rule-based models, demonstrated that integral dimensions are pooled into a single coactive processing channel, in contrast to separable dimensions, which are processed in multiple, independent processing channels. This paper examines the claim that arbitrary dimensions created by factorially morphing four faces are processed in an integral manner. In two experiments, 16 participants completed a categorization task in which either upright or inverted morph stimuli were classified in a speeded fashion. Analyses focused on contrasting different assumptions about the psychological representation of the stimuli, perceptual and decisional separability, and the processing architecture. We report consistent individual differences which demonstrate a mixture of some observers who demonstrate coactive processing with other observers who process the dimensions in a parallel self-terminating manner.

SUMMARYVisual perception is a primary modality for interacting with complex environments. Recent work has shown that the brain and visual system of the honeybee is able, in some cases, to learn complex spatial relationships, while in other cases, bee vision is relatively rudimentary and based upon simple elemental-type visual processing. In the present study, we test the ability of honeybees to learn 4-bar asymmetric patterns in a Y-maze with aversive-appetitive differential conditioning. In Experiment 1, a group of bees were trained at a small visual angle of 50deg by constraining individuals to the decision chamber within the Ymaze. Bees learned this task, and were able to solve the task even in the presence of background noise. However, these bees failed to solve the task when the stimuli were presented at a novel visual angle of 100deg. In Experiment 2, a separate group of bees were trained to sets of 4-bar asymmetric patterns that excluded retinotopic matching and, in this case, bees learned the configural rule describing stimuli at a visual angle of approximately 50deg, and this allowed the bees to solve the task when the stimuli were presented at a novel vision angle of 100deg. This shows that the bee brain contains multiple mechanisms for pattern recognition, and what a bee sees is very dependent upon the specific experience that it receives. These multiple mechanisms would allow bees to interact with complex environments to solve tasks like recognising landmarks at variable distances or quickly discriminating between rewarding/non-rewarding flowers at reasonable constant visual angles. Supplementary material available online at

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urally exists in forage and range problems was abundantly exhibited in the meetings and by the attitude of the members toward forage problems as they came before them. The programme itself exhibited this interest in no mistakable terms, for there were three places allotted 9 10 FOEAGE CONDITIONS ON NORTHERN BORDER OF GREAT BASIN. to addresses on the various phases of grass and forage problems and range reclamation by as many persons. The problems of greatest interest to the meeting appeared to be those relating to the most promising arid land species of forage plants, forage plants for alkali soils, and methods of range management having for their object the greatest permanent efficiency of the native pastures. After the conclusion of the meeting at Douglas the party proceeded directly to Winnemucca, Nev. , and began its work along the Humboldt River bottoms. The lines of investigation covered every phase of forage plant and range questions in the region, and necessitated work along about six lines, namely, studying the native ranges, securing information from the ranchers in the region relative to former conditions, collecting specimens, gathering seed of promising native species of forage plants, digging soil samples, and taking photographs illustrating the various features of the work. 12 FORAGE CONDITIONS ON NORTHERN" BORDER OF GREAT BASIN. Wall barley. 53. Water foxtail. 49. Western couch grass, 49. needle grass. 55. wheat grass, 49. Wild barley, 34. oats. 40, 50. parsnip. 42.

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