Neural discriminability in rat lateral extrastriate cortex and deep but not superficial primary visual cortex correlates with shape discriminability

Recent studies have revealed a surprising degree of functional specialization in rodent visual cortex. It is unknown to what degree this functional organization is related to the well-known hierarchical organization of the visual system in primates. We designed a study in rats that targets one of the hallmarks of the hierarchical object vision pathway in primates: selectivity for behaviorally relevant dimensions. We compared behavioral performance in a visual water maze with neural discriminability in five visual cortical areas. We tested behavioral discrimination in two independent batches of six rats using six pairs of shapes used previously to probe shape selectivity in monkey cortex (Lehky and Sereno, 2007). The relative difficulty (error rate) of shape pairs was strongly correlated between the two batches, indicating that some shape pairs were more difficult to discriminate than others. Then, we recorded in naive rats from five visual areas from primary visual cortex (V1) over areas LM, LI, LL, up to lateral occipito-temporal cortex (TO). Shape selectivity in the upper layers of V1, where the information enters cortex, correlated mostly with physical stimulus dissimilarity and not with behavioral performance. In contrast, neural discriminability in lower layers of all areas was strongly correlated with behavioral performance. These findings, in combination with the results from Vermaercke et al. (2014b), suggest that the functional specialization in rodent lateral visual cortex reflects a processing hierarchy resulting in the emergence of complex selectivity that is related to behaviorally relevant stimulus differences

Falls in older aged adults in 22 European countries : incidence, mortality and burden of disease from 1990 to 2017

Introduction Falls in older aged adults are an important public health problem. Insight into differences in fall-related injury rates between countries can serve as important input for identifying and evaluating prevention strategies. The objectives of this study were to compare Global Burden of Disease (GBD) 2017 estimates on incidence, mortality and disability-adjusted life years (DALYs) due to fall-related injury in older adults across 22 countries in the Western European region and to examine changes over a 28-year period. Methods We performed a secondary database descriptive study using the GBD 2017 results on age-standardised fall-related injury in older adults aged 70 years and older in 22 countries from 1990 to 2017. Results In 2017, in the Western European region, 13 840 per 100 000 (uncertainty interval (UI) 11 837-16 113) older adults sought medical treatment for fall-related injury, ranging from 7594 per 100 000 (UI 6326-9032) in Greece to 19 796 per 100 000 (UI 15 536-24 233) in Norway. Since 1990, fall-related injury DALY rates showed little change for the whole region, but patterns varied widely between countries. Some countries (eg, Belgium and Netherlands) have lost their favourable positions due to an increasing fall-related injury burden of disease since 1990. Conclusions From 1990 to 2017, there was considerable variation in fall-related injury incidence, mortality, DALY rates and its composites in the 22 countries in the Western European region. It may be useful to assess which fall prevention measures have been taken in countries that showed continuous low or decreasing incidence, death and DALY rates despite ageing of the population.Peer reviewe

Verschiedene Kraftsensorprinzipien für flexible Schuheinlagen in der akustischen Ganganalyse (Different force sensor approaches for flexible shoe inlays in acoustic gait analysis)

Acoustic bio-feedback for improving body motion is actually discussed intensively since this kind of feedback is more intuitive than the widely used visual feedback alone, especially for learning new, more healthy motions e.g. after neurologic diseases or sports injuries [1]. For human gait measurement e.g. the sensing of the plantar (= foot describing) pressure distribution as well as measuring and analyzing dynamic parameters like gait line, gait velocity, etc. are necessary. Some of these parameters can be measured by force or pressure sensors below the foot, thus in this paper different sensor approaches for their integration into a sensing shoe inlay are discussed.</p

Neural discriminability in rat lateral extrastriate cortex and deep but not superficial primary visual cortex correlates with shape discriminability

Recent studies have revealed a surprising degree of functional specialization in rodent visual cortex. It is unknown to what degree this functional organization is related to the well-known hierarchical organization of the visual system in primates. We designed a study in rats that targets one of the hallmarks of the hierarchical object vision pathway in primates: selectivity for behaviorally relevant dimensions. We compared behavioral performance in a visual water maze with neural discriminability in five visual cortical areas. We tested behavioral discrimination in two independent batches of six rats using six pairs of shapes used previously to probe shape selectivity in monkey cortex (Lehky and Sereno, 2007). The relative difficulty (error rate) of shape pairs was strongly correlated between the two batches, indicating that some shape pairs were more difficult to discriminate than others. Then, we recorded in naive rats from five visual areas from primary visual cortex (V1) over areas LM, LI, LL, up to lateral occipito-temporal cortex (TO). Shape selectivity in the upper layers of V1, where the information enters cortex, correlated mostly with physical stimulus dissimilarity and not with behavioral performance. In contrast, neural discriminability in lower layers of all areas was strongly correlated with behavioral performance. These findings, in combination with the results from Vermaercke et al. (2014b), suggest that the functional specialization in rodent lateral visual cortex reflects a processing hierarchy resulting in the emergence of complex selectivity that is related to behaviorally relevant stimulus differences.status: publishe

Hierarchical processing of simple shapes and natural movies in rat visual cortex

Recent studies have revealed a surprising degree of functional specialization in rodent visual cortex. However, these studies fall short of establishing a functional hierarchy. We designed a study in rats that targets two hallmarks of the hierarchical object vision pathway in primates: higher tolerance for image transformations and selectivity for behaviorally relevant dimensions. We targeted five visual areas from primary visual cortex (V1) over areas LM, LI, LL, up to lateral occipito-temporal cortex (TO).We examined the responses of single neurons in these regions to six simple shapes used previously to probe monkey anterior infero-temporal cortex. These shapes were slowly jittering around a particular position of the stimulus display during 4s per presentation. After delineating the receptive field (RF) of each neuron, we presented the six shapes around one (Exp. A; N=299 cells) or two (Exp. B; N=258 cells) positions within the RF. First, we quantified the selectivity of populations of neurons in each visual area using all data from Exp. A plus the most responsive position of Exp. B. Overall discrimination performance was highly significant in all visual areas, although it decreased from V1 to higher visual areas. Neighboring areas were correlated with respect to which shape pairs were easiest to discriminate. This correlation suggests that the representation of shape transforms gradually across areas. In addition, we found evidence for an increase in position tolerance along the five areas. In TO, the preference for different shapes at one position was most closely related to the shape preference at another position. Finally, we found strong correlations between TO selectivity and behavioral performance of rats in a discrimination task. These findings demonstrate that the functional specialization in lateral rodent visual cortex reflects a processing hierarchy resulting in the emergence of tolerance and complex selectivity.status: publishe

Functional specialization in rat occipital and temporal visual cortex

Recent studies have revealed a surprising degree of functional specialization in rodent visual cortex. Anatomically, suggestions have been made about the existence of hierarchical pathways with similarities to the ventral and dorsal pathways in primates. Here we aimed to characterize some important functional properties in part of the supposed "ventral" pathway in rats. We investigated the functional properties along a progression of five visual areas in awake rats, from primary visual cortex (V1) over lateromedial (LM), latero-intermediate (LI), and laterolateral (LL) areas up to the newly found lateral occipito-temporal cortex (TO). Response latency increased >20 ms from areas V1/LM/LI to areas LL and TO. Orientation and direction selectivity for the used grating patterns increased gradually from V1 to TO. Overall responsiveness and selectivity to shape stimuli decreased from V1 to TO and was increasingly dependent upon shape motion. Neural similarity for shapes could be accounted for by a simple computational model in V1, but not in the other areas. Across areas, we find a gradual change in which stimulus pairs are most discriminable. Finally, tolerance to position changes increased toward TO. These findings provide unique information about possible commonalities and differences between rodents and primates in hierarchical cortical processing.status: publishe

Transcription and splicing regulation by NLRC5 shape the interferon response in human pancreatic beta-cells

info:eu-repo/semantics/publishe