Social orienting in gaze leading: a mechanism for shared attention

Here, we report a novel social orienting response that occurs after viewing averted gaze. We show, in three experiments, that when a person looks from one location to an object, attention then shifts towards the face of an individual who has subsequently followed the person''s gaze to that same object. That is, contrary to ‘gaze following’, attention instead orients in the opposite direction to observed gaze and towards the gazing face. The magnitude of attentional orienting towards a face that ‘follows’ the participant''s gaze is also associated with self-reported autism-like traits. We propose that this gaze leading phenomenon implies the existence of a mechanism in the human social cognitive system for detecting when one''s gaze has been followed, in order to establish ‘shared attention’ and maintain the ongoing interaction.     

Phonotactic parasitoids and cricket song structure: An evaluation of alternative hypotheses

Summary Calling characteristics of field crickets (Teleogryllus oceanicus) differ between Pacific populations parasitized and unparasitized by a phonotactic fly (Ormia ochracea). Although we inferred that these song differences were due to natural selection by the fly, other environmental differences among sampling localities may also influence the cricket song. To evaluate the contribution of parasitoid pressure to variation in song structure, we analysed calls of crickets from five areas arrayed along a gradient of prevalence of parasitization. A novel use of canonical correlation analysis allowed us to test simultaneously the robustness of alternative hypotheses and their predictions. There is strong inference that selection pressures by phonotactic parasitoid flies have shaped song characteristics of field crickets in the Hawaiian Islands. Not all song components appear to have been equally affected by parasitoid selection and approximately 80–90% of total song variation among individuals is associated with other, unmeasured ecological and environmental attributes.That songs evolve is not disputed, but that they evolved in certain directions or that song structure is due to the action of certain forces, or that differences are due to random evolutionary events, or that they are the result of selection, or that they arise mainly in association with speciation — these are matters for speculation, debate, and analysis.Otte (1992, P. 25)     

Genetically Defined Functional Modules for Spatial Orienting in the Mouse Superior Colliculus

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Spectral position control of dye absorption band maximum in an orienting matrix

The continuous control of the maximum position of the dye absorption band (the zero of the derivative dD ()/d of the cell's optical density D ()) in a nematic matrix is demonstrated experimentally, as a result of changing the angle between the optical axis of a planar-oriented sample and the plane of polarization of absorbed light incident normal to the optical axis. The theory proposed describes quantitatively the experimental dependence (). The rotation of the polarizer with given frequency results in the spectral position modulation of the solute band maximum () within (=0°)–(90°)=700 cm^–1.     

Hindbrain modules differentially transform activity of single collicular neurons to coordinate movements

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