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OHEJP Project MATRIX

We aim to examine to which extent top-down predictions in early visual cortex (EVC) can be related to episodic and semantic memory. In order to do so, we will use a visual occluder and fMRI to measure brain activity on a region of EVC which receives no external stimulation, while the rest of the visual field contains external information that can trigger memory retrieval. Our main goal is to find differential activity patterns within V1 and V2 in the occluded region (Smith and Muckli, 2010) that can be attributed to feedback information based on episodic and semantic memory from the hippocampus and ventromedial prefrontal cortex (vmPFC), respectively.

In this report we describe the commonalities and differences in zoonotic and food-borne disease surveillance systems between the Public health, Animal health and Food safety sectors. Analyses are based on data held within the ORION project Surveillance Inventories, available at: https://shiny.fli.de/ife-apps/EJPOrion_WP2Epi/ . These data describe surveillance systems for zoonotic and food-borne diseases from each sector within several European countries.

OHEJP Project ORION - Workpackage 2 - Epi REVISED OH KNOWLEDGE BASE - EPI, INCLUDING LESSONS LEARNED FROM THE OH PILOTS: - TOXOPLASMA GONDII PILOT STUDIES - Towards a One Health surveillance of hepatitis E in the Netherlands - Promoting the implementation of One Health collaborative approaches between disciplines in Belgium with a focus on the elaboration of the future national One Health Antimicrobial report using qualitative research methodologies - WP2EPI: RASCH MODEL

OHEJP Project ORION - Workpackage 4 OHS KNOWLEDGE HUB POPULATED WITH RESOURCES FROM WP1, WP2 AND WP3 - OHS Codex

Human beings are endowed with a wide range of highly developed cognitive abilities. Which factors have led to this level of intellectual capacity in the course of evo- lution? In cross species studies, overall brain size is a reliable predictor of cognitive performance, but more specific information about how the brain���s structural and functional organization may be linked to these enhancements is lacking. The aim of this thesis was to investigate the role of the anatomy and function of the primary visual cortex (V1) in behaviour. V1 is the earliest sensory stage for vision in the cerebral cortex, and is responsible for processing low-level visual features such as spatial orientation, location and frequency. Interestingly, V1 size displays huge variance between individuals; this offers an amazing opportunity to study the behavioural effect of brain enlargement within a human sample while avoiding the various confounds that can distort the results in cross species studies. Previous research has shown that a larger V1 is linked to higher perceptual sensitivity; but to what extent these size differences may also affect higher cognitive functions is unknown. Using a combined approach of behavioural testing and fMRI brain imaging methods, we find that the acuity of two cognitive functions, namely the precision of visual imagery and visual working memory storage, are significantly positively correlated with the surface size of V1: individuals with a larger V1 tended to have more precise imagery and greater visual working memory storage. In contrast, the strength of visual imagery was negatively related to V1 surface size. In addition, we find that other indices of neural function, such as the concentration of the inhibitory neurotransmitter GABA in the medial occipital cortex and V1 spontaneous functional activity levels, covaried significantly with differences in V1 surface size. Our findings support the notion of a positive relationship between brain (areal) size and cognition and show how even very low-level sensory areas are involved in shaping our intellect. As a last point, we discuss the potential limitations of the positive link between brain size and cognitive ability.

In binocular rivalry, presentation of different images to the separate eyes leads to conscious perception alternating between the two possible interpretations every few seconds. During perceptual transitions, a stimulus emerging into dominance can spread in a wave-like manner across the visual field. These traveling waves of rivalry dominance have been successfully related to the cortical magnification properties and functional activity of early visual areas, including the primary visual cortex (V1). Curiously however, these traveling waves undergo a delay when passing from one hemifield to another. In the current study, we used diffusion tensor imaging (DTI) to investigate whether the strength of interhemispheric connections between the left and right visual cortex might be related to the delay of traveling waves across hemifields. We measured the delay in traveling wave times (Delta TWT) in 19 participants and repeated this test 6 weeks later to evaluate there liability of our behavioral measures. We found large interindividual variability but also good test-retest reliability for individual measures of Delta TWT. Using DTI in connection with fiber tractography, we identified parts of the corpus callosum connecting functionally defined visual areas V1-V3. We found that individual differences in Delta TWT was reliably predicted by the diffusion properties of transcallosal fibers connecting left and right V1, but observed no such effect for neighboring transcallosal visual fibers connecting V2 and V3. Our results demonstrate that the anatomical characteristics of topographically specific transcallosal connections predict the individual delay of interhemispheric traveling waves, providing further evidence that V1 is an important site for neural processes underlying binocular rivalry.