Sensory Surfaces Research Articles

Spatially integrated cortico-subcortical tracing data for analyses of rodent brain topographical organization

The cerebral cortex extends axonal projections to several subcortical brain regions, including the striatum, thalamus, superior colliculus, and pontine nuclei. Experimental tract-tracing studies have shown that these subcortical projections are topographically organized, reflecting the spatial organization of sensory surfaces and body parts. Several public collections of mouse- and rat- brain tract-tracing data are available, with the Allen mouse brain connectivity atlas being most prominent. There, a large body of image data can be inspected, but it is difficult to combine data from different experiments and compare spatial distribution patterns. To enable co-visualization and comparison of topographical organization in mouse brain cortico-subcortical projections across experiments, we represent axonal labelling data as point data in a common 3D brain atlas space. We here present a collection of point-cloud data representing spatial distribution of corticostriatal, corticothalamic, corticotectal, and corticopontine projections in mice and exemplify how these spatially integrated point data can be used as references for experimental investigations of topographic organization in transgenic mice, and for cross-species comparison with corticopontine projections in rats.

Palp sensory structures in adult caddisflies of the suborder Annulipalpia (Trichoptera): a scanning electron microscopy study

Sensory structures and their patterns are investigated by scanning electron microscopy in 38 species representing ten families of the suborder Annuli-palpia (Trichoptera). Palp sensilla comprise seven types: long trichoid, chaetoid, campaniform, mushroom-like pseudoplacoid, petaloid, thick basiconic, and thin basiconic sensilla. Comparative analysis suggests the presence of family-specific patterns of the palp sensory surfaces. Palp sensilla and their sensory patterns persist in the instances of partial palp reduction. Considerations on the evolution trends, functionality, and taxonomic importance of palp sensory structures are provided.

Narrative design for dementia care: Arranging the built environment of care homes to aid communication

AbstractBackgroundThe built environment has been shown to have significant potential to improve the quality of life and contribute to the well‐being of persons living with dementia. Persons with dementia in residential care suffer from isolation as it is difficult for staff and family members to find common routes of communication when the disease progresses. Within dementia care there is an urgent need to further facilitate communication especially with people living with late stage dementia. Storytelling has been effectively used in art therapy and art interventions for people affected by dementia to enhance communication, social connectivity and well‐being.This presentation explores the possibilities of incorporating a novel type of environmental design in care homes that would enhance narrative agency in residents with dementia thus allowing residents, caregivers and staff members to communicate through storytelling.MethodsDrawing on interdisciplinary research, the primary focus of the presentation is a case study examining the implementation of storytelling design in residential care settings. The case study reports on the co‐creation of a space focused on offering lived experiences for residents with dementia in a London care home highlighting design elements that trigger storytelling and stimulate imagination. Such elements include sensory wall surfaces, furniture, soft furnishings, configuration of space and inclusion of technology. The presentation explores whether this type of design could provide routes of communication between residents, staff and family members thus improving the quality of life of people living with dementia.ResultsBased on this case study example, the presentation discusses the value and impact of appropriate storytelling design on the wellbeing of people with dementia and their carers, and future avenues for improving the physical environment in care homes based on narrative design possibilities.ConclusionThere is a possibility for a significant impact of narrative design to communication, social connectivity and well‐being of people living with dementia.

Mouthpart palp sensilla of basal Trichoptera families

A comparative SEM study of palp sensory surfaces in 25 caddisfly species representing seven families reveals seven types of sensilla: long trichoid, blunt chaetoid, campaniform, mushroom-like pseudoplacoid, petaloid, thick basiconic and thin basiconic sensilla. Long trichoid and chaetoid sensilla are present on all segments of both pairs of palps. First and second segments of maxillary palps bear groups of long and sclerotised chaetoid sensilla on their medial surface. Other segments of maxillary palps and all segments of labial palps have shorter and thinner chaetoid sensilla mainly on their ventromedial surfaces. Campaniform sensilla usually occur on the first segment of labial palps and second segment of maxillary palps. Mushroom-like pseudoplacoid sensilla may occupy all palp segments or only distal ones. Petaloid sensilla form sensory fields on apical segments of both pairs of palps in most studied species. Thick basiconic sensilla occur only in apical sensory complexes on tips of maxillary and labial palps. A comparison with the Lepidoptera suggests the similarity in palp sensilla and conservative evolution of the palp surface. The reconstructed ground plan for the palp sensory surfaces in Trichoptera and Amphiesmenoptera is provided.

In the back of your mind: Cortical mapping of paraspinal afferent inputs.

Topographic organisation is a hallmark of vertebrate cortex architecture, characterised by ordered projections of the body's sensory surfaces onto brain systems. High‐resolution functional magnetic resonance imaging (fMRI) has proven itself as a valuable tool to investigate the cortical landscape and its (mal‐)adaptive plasticity with respect to various body part representations, in particular extremities such as the hand and fingers. Less is known, however, about the cortical representation of the human back. We therefore validated a novel, MRI‐compatible method of mapping cortical representations of sensory afferents of the back, using vibrotactile stimulation at varying frequencies and paraspinal locations, in conjunction with fMRI. We expected high‐frequency stimulation to be associated with differential neuronal activity in the primary somatosensory cortex (S1) compared with low‐frequency stimulation and that somatosensory representations would differ across the thoracolumbar axis. We found significant differences between neural representations of high‐frequency and low‐frequency stimulation and between representations of thoracic and lumbar paraspinal locations, in several bilateral S1 sub‐regions, and in regions of the primary motor cortex (M1). High‐frequency stimulation preferentially activated Brodmann Area (BA) regions BA3a and BA4p, whereas low‐frequency stimulation was more encoded in BA3b and BA4a. Moreover, we found clear topographic differences in S1 for representations of the upper and lower back during high‐frequency stimulation. We present the first neurobiological validation of a method for establishing detailed cortical maps of the human back, which might serve as a novel tool to evaluate the pathological significance of neuroplastic changes in clinical conditions such as chronic low back pain.

Scientific Observation Is Socio-Materially Augmented Perception: Toward a Participatory Realism

There is an overlooked similarity between three classic accounts of the conditions of object experience from three distinct disciplines. (1) Sociology: the “inversion” that accompanies discovery in the natural sciences, as local causes of effects are reattributed to an observed object. (2) Psychology: the “externalization” that accompanies mastery of a visual–tactile sensory substitution interface, as tactile sensations of the proximal interface are transformed into vision-like experience of a distal object. (3) Biology: the “projection” that brings forth an animal’s Umwelt, as impressions on its body’s sensory surfaces are reconfigured into perception of an external object. This similarity between the effects of scientific practice and interface-use on the one hand, and of sensorimotor interaction on the other, becomes intelligible once we accept that skillful engagement with instruments and interfaces constitutes a socio-material augmentation of our basic perceptual capacity. This enactive interpretation stands in contrast to anti-realism about science associated with constructivist interpretations of these three phenomena, which are motivated by viewing them as the internal mental construction of the experienced object. Instead, it favors a participatory realism: the sensorimotor basis of perceptual experience loops not only through our body, but also through the external world. This allows us to conceive of object experience in relational terms, i.e., as one or more subjects directly engaging with the world. Consequently, we can appreciate scientific observation in its full complexity: it is a socio-materially augmented process of becoming acquainted with the observed object that—like tool-use and perceiving more generally—is irreducibly self, other-, and world-involving.

Interplay of tactile and motor information in constructing spatial self-perception

During active movement, there is normally a tight relation between motor command and sensory representation about the resulting spatial displacement of the body. Indeed, some theories of space perception emphasize the topographic layout of sensory receptor surfaces, while others emphasize implicit spatial information provided by the intensity of motor command signals. To identify which has the primary role in spatial perception, we developed experiments based on everyday self-touch, in which the right hand strokes the left arm. We used a robot-mediated form of self-touch to decouple the spatial extent of active or passive right hand movements from their tactile consequences. Participants made active movements of the right hand between unpredictable, haptically defined start and stop positions, or the hand was passively moved between the same positions. These movements caused a stroking tactile motion by a brush along the left forearm, with minimal delay, but with an unpredictable spatial gain factor. Participants judged the spatial extent of either the right hand's movement, or of the resulting tactile stimulation to their left forearm. Across five experiments, we found that movement extent strongly interfered with tactile extent perception, and vice versa. Crucially, interference in both directions was stronger during active than passive movements. Thus, voluntary motor commands produced stronger integration of multiple sensorimotor signals underpinning the perception of personal space. Our results prompt a reappraisal of classical theories that reduce space perception to motor command information.

The neuroecology of the water-to-land transition and the evolution of the vertebrate brain.

The water-to-land transition in vertebrate evolution offers an unusual opportunity to consider computational affordances of a new ecology for the brain. All sensory modalities are changed, particularly a greatly enlarged visual sensorium owing to air versus water as a medium, and expanded by mobile eyes and neck. The multiplication of limbs, as evolved to exploit aspects of life on land, is a comparable computational challenge. As the total mass of living organisms on land is a hundredfold larger than the mass underwater, computational improvements promise great rewards. In water, the midbrain tectum coordinates approach/avoid decisions, contextualized by water flow and by the animal's body state and learning. On land, the relative motions of sensory surfaces and effectors must be resolved, adding on computational architectures from the dorsal pallium, such as the parietal cortex. For the large-brained and long-living denizens of land, making the right decision when the wrong one means death may be the basis of planning, which allows animals to learn from hypothetical experience before enactment. Integration of value-weighted, memorized panoramas in basal ganglia/frontal cortex circuitry, with allocentric cognitive maps of the hippocampus and its associated cortices becomes a cognitive habit-to-plan transition as substantial as the change in ecology. This article is part of the theme issue 'Systems neuroscience through the lens of evolutionary theory'.

Robert Kentridge

Robert Kentridge

Olfactory flow in the sturgeon is externally driven

Fluid dynamics plays an important part in olfaction. Using the complementary techniques of dye visualisation and computational fluid dynamics (CFD), we investigated the hydrodynamics of the nasal region of the sturgeon Huso dauricus. H. dauricus offers several experimental advantages, including a well-developed, well-supported, radial array (rosette) of visible-by-eye olfactory sensory channels. We represented these features in an anatomically accurate rigid model derived from an X-ray scan of the head of a preserved museum specimen. We validated the results from the CFD simulation by comparing them with data from the dye visualisation experiments. We found that flow through both the nasal chamber and, crucially, the sensory channels could be induced by an external flow (caused by swimming in vivo) at a physiologically relevant Reynolds number. Flow through the nasal chamber arises from the anatomical arrangement of the incurrent and excurrent nostrils, and is assisted by the broad, cartilage-supported, inner wall of the incurrent nostril. Flow through the sensory channels arises when relatively high speed flow passing through the incurrent nostril encounters the circular central support of the olfactory rosette, decelerates, and is dispersed amongst the sensory channels. Vortices within the olfactory flow may assist odorant transport to the sensory surfaces. We conclude that swimming alone is sufficient to drive olfactory flow in H. dauricus, and consider the implications of our results for the three other extant genera of sturgeons (Acipenser, Pseudoscaphirhynchus and Scaphirhynchus), and for other fishes with olfactory rosettes.

„Niezdeterminowanie” granic poznania w znaturalizowanym relatywizmie pojęciowym W.V.O. Quine’a

<p>W artykule opisano znaturalizowany relatywizm pojęciowy W.V.O. Quine’a w perspektywie problematyki granic wiedzy. Quine był jednocześnie relatywistą pojęciowym (mamy do wyboru wiele równoważnych pod względem epistemologicznym systemów pojęciowych) i empirycznym naturalistą (przyjmował naturalistyczną koncepcję treści empirycznej zredukowanej do pobudzeń odbieranych przez nasze powierzchnie sensoryczne w ramach behawioryzmu lingwistycznego). Ponadto bezpośrednio podejmował zagadnienie granic wiedzy, jednak jego główną intencją – jak sam zaznaczył – była przede wszystkim analiza i modyfikacja tytułowego problemu, a nie próba udzielenia na niego odpowiedzi. Krótko mówiąc, zdaniem Quine’a zagadnienie to można zredukować do kontekstu językowego.</p>

Structural organization of the olfactory organ in an amphihaline migratory fish Hilsa, Tenualosa ilisha.

The histological as well as ultramicroscopic structures of olfactory system of an amphihaline migratory fish hilsa Tenualosa ilisha, were studied. The sexually matured riverine fish were collected from a common breeding habitat-the Hooghly, a tributary of river Ganga, West Bengal, India. This study revealed that the riverine hilsa has larger olfactory bulb compared to marine hilsa with the olfactory lobes well exposed through nostrils. The olfactory lamellae (OL) are 40-45 in number and posses three distinct layers of sensory cells across each lamellae, namely, outer receptor cells (RC), middle sensory cells, and inner basal cells (BC). Besides the above arrangement, the sensory part of olfactory epithelium (OE) also bears rich microvillous cells exposed to the surface of the OE. The sensory and non-sensory surfaces on OL are distinguishable, with clear dendritic cells on sensory epithelium and solitary chemosensory cells on non sensory OE. Abundance of both types of cells in the OE is an indication of its chemoattraction ability towards molecules of amino acid origin. The feature of having abundant, dense, and large dendritic knobs on the surface of OE describes resemblance to the typical morphology of the chemosensory septal organs neuron. The expression of four G protein subunits, like Gαs/olf, Gαq, Gαo, and Gαi-3 in OE indicate that its olfaction is a functional attributes of two olfactory systems, namely main olfactory system and Vomaronasal Olfactory System. Expression of ACIII and PLCβ2 in OE further confirms two signaling pathways involved in odorant reception in hilsa. RESEARCH HIGHLIGHTS: The olfactory bulb in the amphihaline migratory fish hilsa is big in size, with 40-45 lamellae. Its sensory areas showed multilayered cellular features with prominent sensory as well as microvillous cells, whereas non-sensory area possesses solitary chemosensory cells. The expression of four G protein subunits, Gαs/olf, Gαq, Gαo, and Gαi-3 in olfactory epithelium indicates that its olfaction is a functional attributes of two olfactory systems, namely main olfactory system and vomaronasal olfactory system.

Lectin histochemical studies on the olfactory gland and two types of gland in vomeronasal organ of the brown bear

Olfaction is mediated by the vomeronasal and main olfactory systems, and the peripheral vomeronasal organ (VNO) processes species-specific chemicals that are associated with various behaviors in mammals. Sensory epithelial surfaces of the olfactory mucosa and VNO are covered by mucosal fluid that contains secretory products derived from associated glands, and glycoconjugates in the mucosal fluid are involved in odorant reception. The VNO of brown bears contains two types of glands; submucosal vomeronasal glands (VNG) and multicellular intraepithelial glands (MIG). The present study determined the labelling profiles of 21 lectins in the olfactory glands (OG), VNG and MIG of young male brown bears. The OG reacted with 12 lectins, and the VNG and MIG were positive for seven and eight lectins, respectively. Six lectins bound only to the OG, while four reacted with both or either of the VNG and MIG, but not the OG. The differences of lectin labelling pattern between the OG and glands in the VNO suggest that glycans in covering mucosal fluids differ between the olfactory mucosa and VNO. In addition, Bandeiraea simplicifolia lectin-I, Sophora japonica agglutinin and Jacalin reacted with the MIG but not the VNG, whereas Datura stramonium lectin and concanavalin A bound to the VNG, but not the MIG. These findings indicate that the properties of secretory substances differ between the two types of glands in the bear VNO, and that the various secretions from these two types of glands may function in the lumen of VNO together.

Generalized movement representation in haptic perception.

The extraction of spatial information by touch often involves exploratory movements, with tactile and kinesthetic signals combined to construct a spatial haptic percept. However, the body has many tactile sensory surfaces that can move independently, giving rise to the source binding problem: when there are multiple tactile signals originating from sensory surfaces with multiple movements, are the tactile and kinesthetic signals bound to one another? We studied haptic signal combination by applying the tactile signal to a stationary fingertip while another body part (the other hand or a foot) or a visual target moves, and using a task that can only be done if the tactile and kinesthetic signals are combined. We found that both direction and speed of movement transfer across limbs, but only direction transfers between visual target motion and the tactile signal. In control experiments, we excluded the role of explicit reasoning or knowledge of motion kinematics in this transfer. These results demonstrate the existence of 2 motion representations in the haptic system-one of direction and another of speed or amplitude-that are both source-free or unbound from their sensory surface of origin. These representations may well underlie our flexibility in haptic perception and sensorimotor control. (PsycINFO Database Record

Memorializing genocide: embodied semiotics in concentration camp memorials

ABSTRACTTheorists have argued that the “attempt to comprehend” the genocidal event represented by Auschwitz has “defeated the intellects of countless men and women”. Memorials at Auschwitz and other concentration camps such as Dachau and Buchenwald, and to a certain extent those outside of Europe, such as Tuol Sleng and Choeung Ek in Cambodia, are attempts to call attention to these atrocities in the hope of preventing the repetition of their like. Yet these projects, like all historical monuments and memorials, face the problem of a certain coldness and indifference caused by historical distance, consumerist culture and the seemingly abstract nature of historical images and documents. Concentration camp memorials are not entirely immune from these problems. However, in their use of an embodied semiotics invoking the visitor’s own body as a direct participant in immersive environments, sensory surfaces and displays, these memorials engage – not unproblematically – in a project to realize this history in visceral and concrete ways. This paper examines the semiotic strategies of the concentration camp as a technique of “embodying” suffering that is intended to counter the dissipation of affect in a media-saturated consumerist era.

Do terrestrial hermit crabs sniff? Air flow and odorant capture by flicking antennules.

Capture of odorant molecules by olfactory organs from the surrounding fluid is the first step of smelling. Sniffing intermittently moves fluid across sensory surfaces, increasing delivery rates of molecules to chemosensory receptors and providing discrete odour samples. Aquatic malacostracan crustaceans sniff by flicking olfactory antennules bearing arrays of chemosensory hairs (aesthetascs), capturing water in the arrays during downstroke and holding the sample during return stroke. Terrestrial malacostracans also flick antennules, but how their flicking affects odour capture from air is not understood. The terrestrial hermit crab, Coenobita rugosus, uses antennules bearing shingle-shaped aesthetascs to capture odours. We used particle image velocimetry to measure fine-scale fluid flow relative to a dynamically scaled physical model of a flicking antennule, and computational simulations to calculate diffusion to aesthetascs by odorant molecules carried in that flow. Air does not flow into the aesthetasc array during flick downstrokes or recovery strokes. Odorants are captured from air flowing around the outside of the array during flick downstrokes, when aesthetascs face upstream and molecule capture rates are 21% higher than for stationary antennules. Bursts of flicking followed by pauses deliver discrete odour samples to olfactory sensors, causing intermittency in odour capture by a different mechanism than aquatic crustaceans use.

Illusory Tactile Motion Perception: An Analog of the Visual Filehne Illusion.

We continually move our body and our eyes when exploring the world, causing our sensory surfaces, the skin and the retina, to move relative to external objects. In order to estimate object motion consistently, an ideal observer would transform estimates of motion acquired from the sensory surface into fixed, world-centered estimates, by taking the motion of the sensor into account. This ability is referred to as spatial constancy. Human vision does not follow this rule strictly and is therefore subject to perceptual illusions during eye movements, where immobile objects can appear to move. Here, we investigated whether one of these, the Filehne illusion, had a counterpart in touch. To this end, observers estimated the movement of a surface from tactile slip, with a moving or with a stationary finger. We found the perceived movement of the surface to be biased if the surface was sensed while moving. This effect exemplifies a failure of spatial constancy that is similar to the Filehne illusion in vision. We quantified this illusion by using a Bayesian model with a prior for stationarity, applied previously in vision. The analogy between vision and touch points to a modality-independent solution to the spatial constancy problem.

Multisensory Integration: Flexible Use of General Operations

Research into the anatomical substrates and "principles" for integrating inputs from separate sensory surfaces has yielded divergent findings. This suggests that multisensory integration is flexible and context dependent and underlines the need for dynamically adaptive neuronal integration mechanisms. We propose that flexible multisensory integration can be explained by a combination of canonical, population-level integrative operations, such as oscillatory phase resetting and divisive normalization. These canonical operations subsume multisensory integration into a fundamental set of principles as to how the brain integrates all sorts of information, and they are being used proactively and adaptively. We illustrate this proposition by unifying recent findings from different research themes such as timing, behavioral goal, and experience-related differences in integration.

Enhancing nanoparticle deposition using actuated synthetic cilia

We use computational modeling to probe the utility of actuated synthetic cilia lining walls of a microfluidic channel for enhancing the deposition of nanoparticles dispersed in a viscous fluid filling the channel. We demonstrate that elastic cilia actuated by a sinusoidal force applied to their free ends generate circulatory secondary flows facilitating nanoparticle transport. We identify optimal operational conditions in which the effect of cilia beating on particle deposition is maximized. Our simulations also reveal that cilia transition to a three-dimensional beating pattern when the actuation force exceeds a critical value. This transition is associated with buckling instability experienced by elastic cilia. Our findings guide the optimal design of ciliated microfluidic systems for uses such as deposition of particulates onto sensory surfaces and microfluidic mixing.

Using Dynamic Field Theory to extend the embodiment stance toward higher cognition

The embodiment stance emphasizes that cognitive processes unfold continuously in time, are constantly linked to the sensory and motor surfaces, and adapt through learning and development. Dynamic Field Theory (DFT) is a neurally based set of concepts that has turned out to be useful for understanding how cognition emerges in an embodied and situated system. We explore how the embodiment stance may be extended beyond those forms of cognition that are closest to sensorimotor processes. The core elements of DFT are dynamic neural fields (DNFs), patterns of activation defined over different kinds of spaces. These may include retinal space and visual feature spaces, spaces spanned by movement parameters such as movement direction and amplitude, or abstract spaces like the ordinal axis along which sequences unfold. Instances of representation that stand for perceptual objects, motor plans, or action intentions are peaks of activation in the DNFs. We show how such peaks may arise from input and are stabilized by intra-field interaction. Given a neural mechanism for instantiation, the neuronal couplings between DNFs implement cognitive operations. We illustrate how these mechanisms can be used to enable architectures of dynamic neural fields to perform cognitive functions such as acquiring and updating scene representations, using grounded spatial language, and generating sequences of actions. Implementing these DFT models in autonomous robots demonstrates how these cognitive functions can be enacted in embodied, situated systems.