Supralinear and Supramodal Integration of Visual and Tactile Signals in Rats: Psychophysics and Neuronal Mechanisms

To better understand how object recognition can be triggered independently of the sensory channel through which information is acquired, we devised a task in which rats judged the orientation of a raised, black and white grating. They learned to recognize two categories of orientation: 0° ± 45° ("horizontal") and 90° ± 45° ("vertical"). Each trial required a visual (V), a tactile (T), or a visual-tactile (VT) discrimination; VT performance was better than that predicted by optimal linear combination of V and T signals, indicating synergy between sensory channels. We examined posterior parietal cortex (PPC) and uncovered key neuronal correlates of the behavioral findings: PPC carried both graded information about object orientation and categorical information about the rat's upcoming choice; single neurons exhibited identical responses under the three modality conditions. Finally, a linear classifier of neuronal population firing replicated the behavioral findings. Taken together, these findings suggest that PPC is involved in the supramodal processing of shape. Knowledge about objects can be accessed through multiple sensory pathways. Nikbakht et al. find that rats judge object orientation by synergistically combining signals from vision and touch; posterior parietal cortex seems to be involved in the supramodal knowledge of orientation

PIONEER Big Data Platform for Prostate Cancer : Lessons for Advancing Future Real-World Evidence Research

This manuscript has been made open access under a Creative Commons Attribution (CC BY) licence under the terms of the University of Aberdeen Research Publications Policy. https://creativecommons.org/licenses/by/4.0/Peer reviewe

Visual Cortex Limits Pop-Out in the Superior Colliculus of Awake Mice

We detect objects more readily if they differ from their surroundings in motion, color, or texture. This increased saliency is thought to be related to increased responses in the visual cortex. The superior colliculus is another brain area involved in vision and especially in directing gaze and attention. In this study, we show that differences in texture orientation also increase responses in the superficial layers of the superior colliculus that receive retinal and cortical input. We found that gratings evoke more neural response when surrounded by orthogonal gratings than when surrounded by parallel gratings, particularly in the awake mouse. This pop-out is not originating from the visual cortex, and silencing visual cortex increased the relative difference in response. A model shows that this can result from retinotopically matched excitation from visual cortex to the superior colliculus. We suggest that the perceptual saliency of a stimulus differing from its surround in a low-level feature like grating orientation could depend on visual processing in the superior colliculus

Visual stimulus-specific habituation of innate defensive behaviour in mice

Innate defensive responses such as freezing or escape are essential for animal survival. Mice show defensive behaviour to stimuli sweeping overhead, like a bird cruising the sky. Here, we tested this in young male mice and found that mice reduced their defensive freezing after sessions with a stimulus passing overhead repeatedly. This habituation is stimulus-specific, as mice freeze again to a novel shape. We found no evidence for head-centred stimulus location-specific habituation. The mice generalized over a range of sizes and shapes, but distinguished objects when they differed in both size and shape. Innate visual defensive responses are thus strongly influenced by previous experience as mice learn to ignore specific stimuli

Survivorship Data in Prostate Cancer: Where Are We and Where Do We Need To Be?

Cancer survivorship was recently identified as a prostate cancer (PCa) research priority by PIONEER, a European network of excellence for big data in PCa. Despite being a research priority, cancer survivorship lacks a clear and agreed definition, and there is a distinct paucity of patient-reported outcome (PRO) data available on the subject. Data collection on cancer survivorship depends on the availability and implementation of (validated) routinely collected patient-reported outcome measures (PROMs). There have been recent advances in the availability of such PROMs. For instance, the European Organisation for Research and Treatment of Cancer Quality of Life Group (EORTC QLG) is developing survivorship questionnaires. This provides an excellent first step in improving the data available on cancer survivorship. However, we propose that an agreed, standardised definition of (prostate) cancer survivorship must first be established. Only then can real-world data on survivorship be collected to strengthen our knowledge base. With more men than ever surviving PCa, this type of research is imperative to ensure that the quality of life of these men is considered as much as their quantity of life. Patient summary: As there are more prostate cancer survivors than ever before, research into cancer survivorship is crucial. We highlight the importance of such research and provide recommendations on how to carry it out. The first step should be establishing agreement on a standardised definition of survivorship. From this, patient-reported outcome measures can then be used to collect important survivorship data