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A right‐hemispheric superiority in spatial encoding based on geometric cues has been largely documented in a variety of species, together with a left‐hemispheric specialization for encoding based on landmarks. In humans, hemispheric asymmetries for spatial encoding have been little explored. In this study, we compared a patient with a complete callosal resection (D.D.C.) and a patient with a wide callosal resection saving the splenium (A.P.), with healthy participants. In two 2D versions of the ‘reorientation task’, participants were asked to find the target corner of a rectangle‐shaped environment, by exploiting either geometric information alone or the combination of geometric and landmark information. In Experiment 1, the landmark consisted of a coloured side of the rectangle; in Experiment 2, this cue was replaced by a coloured disc located inside the rectangle. In both experiments, the rectangular shape ensured the geometric cue. D.D.C. was always unable to recall the target, whereas A.P. correctly solved the task when only the geometric information was available, without difference with respect to the controls. Importantly, the performance of A.P. did not differ from controls’ when the right hemisphere was tested with the landmark cues (the task being carried out using the left hand), whereas when the left hemisphere was tested (right‐hand session) his performance was worse than controls’ with the coloured side of the space, but it was better than controls’ with the coloured disc. The results are discussed comparing them with data collected on other species, and with theories of spatial processing. [ABSTRACT FROM AUTHOR]

BACKGROUND Table olives have been a component of the Mediterranean diet for centuries, with the trend for their consumption currently increasing worldwide. They are rich in bioactive molecules with nutritional, antioxidant, anti-inflammatory or hormone-like properties. In the present study, the concentrations of phenolics, triterpenic acids, carotenoids and vitamins, as well as fatty acid profiles and antioxidant activity, were analyzed in the edible portion of black table olives ( Olea europea L.) from Italian (Cellina di Nardò and Leccino) and Greek (Kalamàta and Conservolea) cultivars fermented with selected autochthonous starters and in the corresponding monovarietal olive oils. RESULTS On a fresh weight basis, Cellina di Nardò and Leccino table olives showed the highest total phenolic content. No significant differences were found with respect to the levels of total triterpenic (maslinic and oleanolic) acids and vitamin E among cultivars. All table olives were characterized by high amounts of oleic, linoleic and palmitic acids. Oils were richer in lipophilic antioxidants (carotenoids and tocochromanols) than table olives, which, instead, showed a higher content of polyphenols and triterpenic acids than oils. CONCLUSION The present study demonstrates that fermented table olives are an excellent natural source of unsaturated fatty acids, as well as being nutritionally important health-promoting bioactive compounds. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The 'silhouette illusion', representing the silhouette of a female dancer pirouetting about her vertical axis, is a bistable stimulus created by Japanese web designer Nobuyuki Kayahara. Although the dancer can be perceived as spinning either clockwise or counterclockwise, the clockwise rotation is usually preferred. Troje and McAdam ( i-Perception, 2010, 1, 143) showed that this clockwise bias can be attributed to the tendency to assume a viewpoint from above rather than from below, given that the dancer is portrayed from a vantage point that is not perpendicular to the axis of rotation. Here, we tested whether another possible factor contributing to the observers' interpretation of this bistable stimulus might be the tendency to perceive movements of the right rather than the left foot. We confirmed both the viewing-from-above bias and our hypothesis. The bias to perceive movements of the right leg might be a generalization to lower limbs of a perceptual frequency effect already observed for upper limbs. Such a perceptual and attentional bias towards the right hand/foot could account for the greater ability to predict the outcome of sport actions when observing right- rather than left-limbed movements, and thus the left-handers' and left-footers' advantage observed in a variety of interactive sports. [ABSTRACT FROM AUTHOR]

In a high-resolution electroencephalographic study, participants evaluated the friendliness level of upright and inverted 'hybrid faces', i.e. facial photos containing a subliminal emotional core in the low spatial frequencies (< 6 cycles/image), superimposed on a neutral expression in the rest of the spatial frequencies. Upright happy and angry faces were judged as more friendly or less friendly than neutral faces, respectively. We observed the time course of cerebral correlates of these stimuli with event-related potentials (ERPs), confirming that hybrid faces elicited the posterior emotion-related and face-related components (P1, N170 and P2), previously shown to be engaged by non-subliminal emotional stimuli. In addition, these components were stronger in the right hemisphere and were both enhanced and delayed by face inversion. A frontal positivity (210-300 ms) was stronger for emotional than for neutral faces, and for upright than for inverted faces. Hence, hybrid faces represent an original approach in the study of subliminal emotions, which appears promising for investigating their electrophysiological correlates. [ABSTRACT FROM AUTHOR]

We investigated how the brain's hemispheres process explicit and implicit facial expressions in two 'split-brain' patients (one with a complete and one with a partial anterior resection). Photographs of faces expressing positive, negative or neutral emotions were shown either centrally or bilaterally. The task consisted in judging the friendliness of each person in the photographs. Half of the photograph stimuli were 'hybrid faces', that is an amalgamation of filtered images which contained emotional information only in the low range of spatial frequency, blended to a neutral expression of the same individual in the rest of the spatial frequencies. The other half of the images contained unfiltered faces. With the hybrid faces the patients and a matched control group were more influenced in their social judgements by the emotional expression of the face shown in the left visual field (LVF). When the expressions were shown explicitly, that is without filtering, the control group and the partially callosotomized patient based their judgement on the face shown in the LVF, whereas the complete split-brain patient based his ratings mainly on the face presented in the right visual field. We conclude that the processing of implicit emotions does not require the integrity of callosal fibres and can take place within subcortical routes lateralized in the right hemisphere. [ABSTRACT FROM AUTHOR]

In this overview, focusing on memory and higher cognitive processes, we cover some of the most relevant results that emerged from research on spatial cognition in animals and in humans in the last 3 decades. In particular, we discuss how representations of distance and direction are used to localize oneself with respect to the external world, to determine the position of objects with respect to each other, and to compute the position of invisible goals. The role of landmarks and environmental geometry as cues for extracting spatial information in such abilities is compared, and the reliance upon self-centered and external frames of reference is discussed. Moreover, the contribution of working memory and processing strategies in forming representations of spatial relations in humans is presented. Finally, implications for some neighboring fields of the cognitive sciences will be outlined. WIREs Cogn Sci 2012. doi: 10.1002/wcs.1198 For further resources related to this article, please visit the WIREs website. [ABSTRACT FROM AUTHOR]

Miraculin, the extract of miracle fruit (Richadella dulcifica or Synsepalum dulcificum), is a taste‐modifying protein, its effect consisting in a temporary and almost complete replacement of sour taste with sweet taste. Despite psychophysical investigations were carried out in the past, very little is known about the effect of this molecule on taste interactions. We investigated the changes induced by miraculin on the gustatory sensations evoked by isolated tastants (citric acid, caffeine, NaCl and sucrose) and by binary and trinary mixtures that included a sour tastant (citric acid). We confirmed the effects of miraculin on citric acid, both as a single tastant and in mixtures. In mixtures including a salty tastant, the "illusory sweetness" induced by miraculin significantly reduced saltiness. Variable effects were shown on the perception of bitterness, although mostly in the direction of bitterness suppression. Finally, contrary to previous results, miraculin added sweetness in mixtures that included a sweet tastant. PRATICAL APPLICATIONS: The taste‐modifying protein miraculin has been known since long time due to its surprising property of transforming sourness into sweetness. Here, we put at test the properties of miraculin in mixtures, proving that its sweetness‐inducing effect has an impact also on saltiness and bitterness, provided that the mixture includes a sour tastant (citric acid). In all mixtures containing NaCl (sour‐salty, sour‐salty‐bitter and sour‐salty‐sweet), saltiness was significantly reduced, suggesting a suppressive interaction between miraculin‐induced sweetness and NaCl. Similarly, although less strongly, the bitterness (of caffeine) was suppressed in two mixtures out of three (sour‐bitter and sour‐bitter‐sweet). [ABSTRACT FROM AUTHOR]

Abstract Domestic chicks bilaterally or unilaterally lesioned to the hippocampus were trained to search for food hidden beneath sawdust by ground-scratching in the centre of a large enclosure, the correct position of food being indicated by a local landmark in the absence of any extra-enclosure visual cues. At test, the landmark was removed or displaced at a distance from its original position. Results showed that sham-operated chicks and chicks with a lesion of the left hippocampus searched in the centre, relying on large-scale geometric information provided by the enclosure, whereas chicks with a lesion of either the right hippocampus or both hippocampi were completely disoriented (landmark removed) or searched close to the landmark shifted from the centre (landmark displaced). These results indicate that encoding of geometric features of an enclosure occurs in the right hippocampus even when local information provided by a landmark would suffice to localize the goal; encoding based on local information, in contrast, seems to occur outside the hippocampus. These findings provide evidence that the left and right avian hippocampi play different roles in spatial cognition, a phenomenon which had been documented previously only for the human hippocampus. [ABSTRACT FROM AUTHOR]