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The brain enhances its perceptual and behavioral decisions by integrating information from its multiple senses in what are believed to be optimal ways. This phenomenon of "multisensory integration" appears to be pre‐conscious, effortless, and highly efficient. The present experiments examined whether experience could modify this seemingly automatic process. Cats were trained in a localization task in which congruent pairs of auditory‐visual stimuli are normally integrated to enhance detection and orientation/approach performance. Consistent with the results of previous studies, animals more reliably detected and approached cross‐modal pairs than their modality‐specific component stimuli, regardless of whether the pairings were novel or familiar. However, when provided evidence that one of the modality‐specific component stimuli had no value (it was not rewarded) animals ceased integrating it with other cues, and it lost its previous ability to enhance approach behaviors. Cross‐modal pairings involving that stimulus failed to elicit enhanced responses even when the paired stimuli were congruent and mutually informative. However, the stimulus regained its ability to enhance responses when it was associated with reward. This suggests that experience can selectively block access of stimuli (i.e., filter inputs) to the multisensory computation. Because this filtering process results in the loss of useful information, its operation and behavioral consequences are not optimal. Nevertheless, the process can be of substantial value in natural environments, rich in dynamic stimuli, by using experience to minimize the impact of stimuli unlikely to be of biological significance, and reducing the complexity of the problem of matching signals across the senses. [ABSTRACT FROM AUTHOR]

The operation of our multiple and distinct sensory systems has long captured the interest of researchers from multiple disciplines. When the Society was founded 50 years ago to bring neuroscience research under a common banner, sensory research was largely divided along modalityspecific lines. At the time, there were only a few physiological and anatomical observations of the multisensory interactions that powerfully influence our everyday perception. Since then, the neuroscientific study of multisensory integration has increased exponentially in both volume and diversity. From initial studies identifying the overlapping receptive fields of multisensory neurons, to subsequent studies of the spatial and temporal principles that govern the integration of multiple sensory cues, our understanding of this phenomenon at the single-neuron level has expanded to include a variety of dimensions. We now can appreciate how multisensory integration can alter patterns of neural activity in time, and even coordinate activity among populations of neurons across different brain areas. There is now a growing battery of sophisticated empirical and computational techniques that are being used to study this process in a number of models. These advancements have not only enhanced our understanding of this remarkable process in the normal adult brain, but also its underlying circuitry, requirements for development, susceptibility to malfunction, and how its principles may be used to mitigate malfunction. [ABSTRACT FROM AUTHOR]

The ability to integrate information across multiple senses enhances the brain’s ability to detect, localize, and identify external events. This process has been well documented in single neurons in the superior colliculus (SC), which synthesize concordant combinations of visual, auditory, and/or somatosensory signals to enhance the vigor of their responses. This increases the physiological salience of crossmodal events and, in turn, the speed and accuracy of SC-mediated behavioral responses to them. However, this capability is not an innate feature of the circuit and only develops postnatally alter the animal acquires sufficient experience with covariant crossmodal events to form links between their modality-specific components. Of critical importance in this process are tectopetal influences from association cortex. Recent findings suggest that, despite its intuitive appeal, a simple generic associative rule cannot explain how this circuit develops its ability to integrate those crossmodal inputs to produce enhanced multisensory responses. The present neurocomputational model explains how this development can be understood as a transition from a default state in which crossmodal SC inputs interact competitively to one in which they interact cooperatively. Crucial to this transition is the operation of a learning rule requiring coactivation among tectopetal afferents for engagement. The model successfully replicates findings of multisensory development in normal cats and cats of either sex reared with special experience. In doing so, it explains how the cortico-SC projections can use crossmodal experience to craft the multisensory integration capabilities of the SC and adapt them to the environment in which they will be used. [ABSTRACT FROM AUTHOR]

The ability to use cues from multiple senses in concert is a fundamental aspect of brain function. It maximizes the brain’s use of the information available to it at any given moment and enhances the physiological salience of external events. Because each sense conveys a unique perspective of the external world, synthesizing information across senses affords computational benefits that cannot otherwise be achieved. Multisensory integration not only has substantial survival value but can also create unique experiences that emerge when signals from different sensory channels are bound together. However, neurons in a newborn’s brain are not capable of multisensory integration, and studies in the midbrain have shown that the development of this process is not predetermined. Rather, its emergence and maturation critically depend on cross-modal experiences that alter the underlying neural circuit in such a way that optimizes multisensory integrative capabilities for the environment in which the animal will function. [ABSTRACT FROM AUTHOR]

The ability to use cues from multiple senses in concert is a fundamental aspect of brain function. It maximizes the brain's use of the information available to it at any given moment and enhances the physiological salience of external events. Because each sense conveys a unique perspective of the external world, synthesizing information across senses affords computational benefits that cannot otherwise be achieved. Multisensory integration not only has substantial survival value but can also create unique experiences that emerge when signals from different sensory channels are bound together. However, neurons in a newborn's brain are not capable of multisensory integration, and studies in the midbrain have shown that the development of this process is not predetermined. Rather, its emergence and maturation critically depend on cross-modal experiences that alter the underlying neural circuit in such a way that optimizes multisensory integrative capabilities for the environment in which the animal will function. [ABSTRACT FROM AUTHOR]

Highlights: [•] Multisensory responses begin, rise, and peak earlier than unisensory responses. [•] Different computations are evident in different portions of the response. [•] Essential empirical findings are captured by a minimalist neural network model. [•] This model is easily inserted into broader artificial implementations. [Copyright &y& Elsevier]

Here we report the functionalization of monodisperseiron oxidenanoparticles (NPs) with commercially available functional acids containingmultiple double bonds such as linolenic (LLA) and linoleic (LEA) acidsor pyridine moieties such as 6-methylpyridine-2-carboxylic acid, isonicotinicacid, 3-hydroxypicolinic acid, and 6-(1-piperidinyl)pyridine-3-carboxlicacid (PPCA). Both double bonds and pyridine groups can be reactedwith noble metal compounds to form catalytically active species inthe exterior of magnetic NPs, thus making them promising magneticallyrecoverable catalysts. We determined that both LLA and LEA stabilizemagnetic iron oxide NPs, allowing the formation of π-complexeswith bis(acetonitrile)dichloropalladium(II) in the NP shells. In bothcases, this leads to the formation of NP aggregates because of interparticlecomplexation. In the case of pyridine-containing ligands, only PPCAwith two N-containing rings is able to provide NP stabilization andfunctionalization whereas other pyridine-containing acids did nowallow sufficient steric stabilization. The interaction of PPCA-basedparticles with Pd acetate also leads to aggregation because of interparticleinteractions, but the aggregates that are formed are much smaller.Nevertheless, the catalytic properties in the selective hydrogenationof dimethylethynylcarbinol (DMEC) to dimethylvinylcarbinol were thebest for the catalyst based on LLA, demonstrating that the NP aggregatesin all cases are penetrable for DMEC. Easy magnetic separation ofthis catalyst from the reaction solution makes it promising as a magneticallyrecoverable catalyst. [ABSTRACT FROM AUTHOR]

Non-technical summary The superior colliculus (SC) is a subcortical brain structure critically involved in the production of eye and head movements to novel or salient visual cues. But to accomplish its function, an input from visual cortex also is required. Because visual cortex projects directly to the SC, this route is typically viewed as the predominant way by which cortex exerts higher-level control over SC-mediated behaviours. However, anatomical studies suggest that other multi-neuronal circuits through the basal ganglia, a collection of interconnected structures involved in decision making, might provide an alternative way for cortex to influence the SC. The present study provides physiological evidence for such an alternative route and affords additional insights into how the brain initiates and controls movements in response to visual cues. Such knowledge could be important for developing therapies to lessen the effects of visual deficits in patients experiencing loss of function following head trauma or stroke. [ABSTRACT FROM AUTHOR]

Multisensory neurons in cat SC exhibit significant postnatal maturation. The first multisensory neurons to appear have large receptive fields (RFs) and cannot integrate information across sensory modalities. During the first several months of postnatal life RFs contract, responses become more robust and neurons develop the capacity for multisensory integration. Recent data suggest that these changes depend on both sensory experience and active inputs from association cortex. Here, we extend a computational model we developed (Cuppini et al. in Front Integr Neurosci 22: 4-6, ) using a limited set of biologically realistic assumptions to describe how this maturational process might take place. The model assumes that during early life, cortical-SC synapses are present but not active and that responses are driven by non-cortical inputs with very large RFs. Sensory experience is modeled by a 'training phase' in which the network is repeatedly exposed to modality-specific and cross-modal stimuli at different locations. Cortical-SC synaptic weights are modified during this period as a result of Hebbian rules of potentiation and depression. The result is that RFs are reduced in size and neurons become capable of responding in adult-like fashion to modality-specific and cross-modal stimuli. Supported by NIH grants NS036916 and EY016716. [ABSTRACT FROM AUTHOR]

The article discusses the development of the Critical Thinking Assessment Test (CAT), a faculty-driven tool used to assess the critical thinking skills of students, by faculty from various institutions and disciplines in the U.S. The faculty established a core set of skills that were considered as important components of critical thinking across disciplines and formulated questions to evaluate those skills. Among the institutions involved in development and implementation of the CAT are the Tennessee Technological University (TTU), the University of Texas at Austin and the University of Washington at Seattle.

There is now a good deal of data from neurophysiological studies in animals and behavioral studies in human infants regarding the development of multisensory processing capabilities. Although the conclusions drawn from these different datasets sometimes appear to conflict, many of the differences are due to the use of different terms to mean the same thing and, more problematic, the use of similar terms to mean different things. Semantic issues are pervasive in the field and complicate communication among groups using different methods to study similar issues. Achieving clarity of communication among different investigative groups is essential for each to make full use of the findings of others, and an important step in this direction is to identify areas of semantic confusion. In this way investigators can be encouraged to use terms whose meaning and underlying assumptions are unambiguous because they are commonly accepted. Although this issue is of obvious importance to the large and very rapidly growing number of researchers working on multisensory processes, it is perhaps even more important to the non-cognoscenti. Those who wish to benefit from the scholarship in this field but are unfamiliar with the issues identified here are most likely to be confused by semantic inconsistencies. The current discussion attempts to document some of the more problematic of these, begin a discussion about the nature of the confusion and suggest some possible solutions. [ABSTRACT FROM AUTHOR]

Multisensory neurons in the superior colliculus (SC) have the capability to integrate signals that belong to the same event, despite being conveyed by different senses. They develop this capability during early life as experience is gained with the statistics of cross-modal events. These adaptations prepare the SC to deal with the cross-modal events that are likely to be encountered throughout life. Here, we found that neurons in the adult SC can also adapt to experience with sequentially ordered cross-modal (visual-auditory or auditoryvisual) cues, and that they do so over short periods of time (minutes), as if adapting to a particular stimulus configuration. This short-term plasticity was evident as a rapid increase in the magnitude and duration of responses to the first stimulus, and a shortening of the latency and increase in magnitude of the responses to the second stimulus when they are presented in sequence. The result was that the two responses appeared to merge. These changes were stable in the absence of experience with competing stimulus configurations, outlasted the exposure period, and could not be induced by equivalent experience with sequential within-modal (visual-visual or auditory-auditory) stimuli. A parsimonious interpretation is that the additional SC activity provided by the second stimulus became associated with, and increased the potency of, the afferents responding to the preceding stimulus. This interpretation is consistent with the principle of spike-timing-dependent plasticity, which may provide the basic mechanism for short term or long term plasticity and be operative in both the adult and neonatal SC. [ABSTRACT FROM AUTHOR]

Abstract: Multisensory integration describes a process by which information from different sensory systems is combined to influence perception, decisions, and overt behavior. Despite a widespread appreciation of its utility in the adult, its developmental antecedents have received relatively little attention. Here we review what is known about the development of multisensory integration, with a focus on the circuitry and experiential antecedents of its development in the model system of the multisensory (i.e., deep) layers of the superior colliculus. Of particular interest here are two sets of experimental observations: (1) cortical influences appear essential for multisensory integration in the SC, and (2) postnatal experience guides its maturation. The current belief is that the experience normally gained during early life is instantiated in the cortico-SC projection, and that this is the primary route by which ecological pressures adapt SC multisensory integration to the particular environment in which it will be used. [Copyright &y& Elsevier]

Single-neuron studies provide a foundation for understanding many facets of multisensory integration. These studies have used a variety of criteria for identifying and quantifying multisensory integration. While a number of techniques have been used, an explicit discussion of the assumptions, criteria, and analytical methods traditionally used to define the principles of multisensory integration is lacking. This was not problematic when the field was small, but with rapid growth a number of alternative techniques and models have been introduced, each with its own criteria and sets of implicit assumptions to define and characterize what is thought to be the same phenomenon. The potential for misconception prompted this reexamination of traditional approaches in order to clarify their underlying assumptions and analytic techniques. The objective here is to review and discuss traditional quantitative methods advanced in the study of single-neuron physiology in order to appreciate the process of multisensory integration and its impact. [ABSTRACT FROM AUTHOR]

Large unilateral visual cortex lesions produce enduring contralesional visual orientation deficits. To examine whether glutamate excitotoxicity is involved in establishing these deficits, cats were pretreated with the NMDA receptor antagonist dizocilpine (MK-801) 30 min before unilateral visual cortex ablation. Pretreated MK-801 animals were trained first in an orientation task in which they were required to fixate directly ahead and then orient to stimuli introduced at various eccentricities throughout the visual field. They did not display the characteristic ipsilesional head and neck asymmetries and/or spontaneous ipsiversive rotational behaviors or show the profound contralesional visual neglect seen postoperatively in nonpretreated control animals. Rather, pretreated animals were able to orient to visual stimuli in the contralesional hemifield immediately following surgical recovery. Postmortem histology revealed severe retrograde degeneration of the ipsilesional lateral geniculate nucleus in both experimental groups, suggesting that postlesion visuomotor behavioral competencies in pretreated animals are attributable to preserved function in nongeniculocortical visual pathways. These observations are consistent with the hypothesis that visual cortex lesions normally induce secondary alterations via NMDA-mediated excitotoxicity in these other pathways that prevents them from supporting visuomotor behaviors. The similar behavioral competencies of MK-801- pretreated animals and those whose lesion-induced deficits are ameliorated by removing basal ganglia afferents to the ipsilesional superior colliculus are consistent with this hypothesis and highlight the normal functional capabilities of this circuit. It is likely that MK-801 pretreatment acts, at least in part, by preserving the normal interhemispheric control dynamics with which the basal ganglia influence superior colliculus-mediated orientation behaviors. [ABSTRACT FROM AUTHOR]

For thousands of years science philosophers have been impressed by how effectively the senses work together to enhance the salience of biologically meaningful events. However, they really had no idea how this was accomplished. Recent insights into the underlying physiological mechanisms reveal that, in at least one circuit, this ability depends on an intimate dialogue among neurons at multiple levels of the neuraxis; this dialogue cannot take place until long after birth and might require a specific kind of experience. Understanding the acquisition and usage of multisensory integration in the midbrain and cerebral cortex of mammals has been aided by a multiplicity of approaches. Here we examine some of the fundamental advances that have been made and some of the challenging questions that remain. [ABSTRACT FROM AUTHOR]

A Coxiella-type microbe occurs at 100% frequency in all Amblyomma americanum ticks thus far tested. Using laboratory-reared ticks free of other microbes, we identified the Amblyomma-associated Coxiella microbe in several types of tissue and at various stages of the life cycle of A. americanum by 16S rRNA gene sequencing and diagnostic PCR. We visualized Amblyomma-associated Coxiella through the use of a diagnostic fluorescence in situ hybridization (FISH) assay supplemented with PCR-based detection, nucleic acid fluorescent staining, wide-field epifluorescence and confocal microscopy, and transmission electron microscopy (TEM). Specific fluorescent foci were observed in several tick tissues, including the midgut and the Malpighian tubules, but particularly bright signals were observed in the granular acini of salivary gland clusters and in both small and large oocytes. TEM confirmed intracellular bacterial structures in the same tissues. The presence of Amblyomma-associated Coxiella within oocytes is consistent with the vertical transmission of these endosymbionts. Further, the presence of the Amblyomma-associated Coxiella symbiont in other tissues such as salivary glands could potentially lead to interactions with horizontally acquired pathogens. [ABSTRACT FROM AUTHOR]

The superior colliculus (SC) plays an important role in integrating visual, auditory and somatosensory information, and in guiding the orientation of the eyes, ears and head. Previously we have shown that cats with unilateral SC lesions showed a preferential loss of multisensory orientation behaviors for stimuli contralateral to the lesion. Surprisingly, this behavioral loss was seen even under circumstances where the SC lesion was far from complete. To assess the physiological changes induced by these lesions, we employed single unit electrophysiological methods to record from individual neurons in both the intact and damaged SC following behavioral testing in two animals. In the damaged SC of these animals, multisensory neurons were preferentially reduced in incidence, comprising less than 25% of the sensory-responsive population (as compared with 49% on the control side). In those multisensory neurons that remained following the lesion, receptive fields were nearly twofold larger, and less than 25% showed normal patterns of multisensory integration, with those that did being found in areas outside of the lesion. These results strongly suggest that the multisensory behavioral deficits seen following SC lesions are the combined result of a loss of multisensory neurons and a loss of multisensory integration in those neurons that remain. [ABSTRACT FROM AUTHOR]

Multisensory integration refers to the process by which the brain synthesizes information from different senses to enhance sensitivity to external events. In the present experiments, animals were reared in an altered sensory environment in which visual and auditory stimuli were temporally coupled but originated from different locations. Neurons in the superior colliculus developed a seemingly anomalous form of multisensory integration in which spatially disparate visual-auditory stimuli were integrated in the same way that neurons in normally reared animals integrated visual-auditory stimuli from the same location. The data suggest that the principles governing multisensory integration are highly plastic and that there is no a priori spatial relationship between stimuli from different senses that is required for their integration. Rather, these principles appear to be established early in life based on the specific features of an animal’s environment to best adapt it to deal with that environment later in life. [ABSTRACT FROM AUTHOR]

The anterior ectosylvian (AES) and rostral lateral suprasylvian (rLS) sulci send critical signals to multisensory superior colliculus (SC) neurons that enable them to integrate information from different senses. When either of these areas is temporarily deactivated in adult animals, the ability of SC neurons to integrate multisensory information and, thereby, enhance their responses to cross-modal stimuli is temporarily compromised. As a consequence, the ability to use cross-modal stimuli to enhance SC-mediated behavioral performance is also compromised. In contrast, removal of either one of these areas during early life has little effect on the development of multisensory processes in the SC or on SC-mediated multisensory behaviors and these animals seem very similar to normal controls. These observations suggest that there is considerable plasticity in these cortico-collicular systems during early life, with each area able to compensate for the early loss of the other. However, when both AES and rLS are removed early in life, there appears to be no compensation. The SC neurons now deal with sensory stimuli, even those embedded in multisensory complexes, as if they were there alone, precluding any SC-mediated behavioral benefit to cross-modal stimuli. [ABSTRACT FROM AUTHOR]

Multisensory depression is a fundamental index of multisensory integration in superior colliculus (SC) neurons. It is initiated when one sensory stimulus (auditory) located outside its modality-specific receptive field degrades or eliminates the neuron's responses to another sensory stimulus (visual) presented within its modality-specific receptive field. The present experiments demonstrate that the capacity of SC neurons to engage in multisensory depression is strongly dependent on influences from two cortical areas (the anterior ectosylvian and rostral lateral suprasylvian sulci). When these cortices are deactivated, the ability of SC neurons to synthesize visual-auditory inputs in this way is compromised; multisensory responses are disinhibited, becoming more vigorous and in some cases indistinguishable from responses to the visual stimulus alone. Although obtaining a more robust multisensory SC response when cortex is nonfunctional than when it is functional may seem paradoxical, these data may help explain previous observations that the loss of these cortical influences permits visual orientation behavior in the presence of a normally disruptive auditory stimulus. [ABSTRACT FROM AUTHOR]

Physiological and behavioral studies in animal models have revealed that information from the different senses can be used synergistically to enhance the detection of objects and events. Although a great deal of evidence exists which demonstrates the synergistic use of multisensory cues in human behavior and perception, there is conflicting evidence about whether such interactions can be used to aid in stimulus detection. To examine this issue, we had volunteers indicate the presence or absence of a brief, low-intensity sound that was either presented alone or paired with a simultaneous light in a one-interval signal detection task. In the first experiment, the task-irrelevant light was found to enhance the detectability of the sound, but also to increase the subject’s willingness to report the presence of a sound (i.e., response bias). In the second experiment, designed to eliminate this response bias, we found an improvement in stimulus detectability in the absence of any change in bias. These findings demonstrate the presence of a significant multisensory-mediated gain in stimulus detection in human subjects. [Copyright &y& Elsevier]

The manner in which the nervous system allocates limited motor resources when confronted with conflicting behavioural demands is a crucial issue in understanding how sensory information is transformed into adaptive motor responses. Understanding this selection process is of particular concern in current models of functions of the basal ganglia[SUP1]. Here we report that the basal ganglia use simultaneous enhancing and suppressing processes synergistically to modulate sensory activity in the superior colliculi, which are bilaterally paired midbrain structures involved in the control of visual orientation behaviours[SUP2]. These complementary processes presumably ensure accurate gaze shifts mediated by the superior colliculi despite the presence of potential distractors. [ABSTRACT FROM AUTHOR]

Neurons in the superior colliculus (SC), a prominent midbrain structure, are able to synthesize information from different senses. This synthesis plays an important role in determining whether SC-mediated orientation behaviors will be initiated. In some circumstances, multisensory integration in the SC is evident as a response that is significantly enhanced above that evoked by the most effective single-modality stimulus. It can sometimes even exceed the arithmetic sum of the single-modality responses. In other circumstances, multisensory integration is evident as response depression, an effect sometimes powerful enough to eliminate even robust single-modality responses. The conditions that produce multisensory enhancement also increase the probability of orientation responses, and those that produce multisensory response depression decrease the probability of orientation responses. Although one might posit that the capability to integrate cross-modal cues (and, in this case, alter overt behavior) would be evident in all neurons capable of responding to stimuli from two or more sensory modalities, this turns out to be incorrect. When descending influences from the cortex are temporarily inactivated, SC neurons are rendered unable to synthesize their multiple sensory inputs, and animals no longer show enhanced orientation responses. Nevertheless, the ability to respond to cues from multiple sensory modalities is retained at both the single neuron and behavioral levels. Two cortical areas have been implicated in controlling these midbrain processes: the anterior ectosylvian sulcus and the rostral lateral suprasylvian sulcus. [ABSTRACT FROM AUTHOR]

Describes the etiology and clinical course of acute colitis occurring after flexible endoscopy. Relation of presenting symptoms to glutaraldehyde exposure; Response to therapy and the need for further therapy; Characterization of the disease condition; Prevention.

By pooling and integrating signals from different sensory channels, specialized populations of “multisensory” neurons not only help to maximize the brain's ability to detect and identify external events, but also help to initiate reactions to them. Although multisensory neurons are found in many areas of the brain, those in the midbrain (i.e., superior colliculus, SC) have been studied most extensively and have served as a model for understanding some of the neural operating principles of multisensory integration, as well as the impact of these processes on overt attentive and orientation behaviors. However, this capability is not hard-wired at birth. Very young SC neurons are responsive only to unimodal inputs; it is not until many days later that some of them begin to respond to inputs from more than a single sensory modality, and even then they are not yet capable of integrating these inputs to produce the synthesized multisensory signals that characterize the normal adult. The most significant occurrence to precede this maturational change is the appearance of influences from association regions of the neocortex. These influences appear abruptly on any given individual neuron, but because different neurons are targeted at different times during development, it takes many weeks before the mature complement of such neurons is achieved. It is likely that the maturational timing of the interplay between the cortex and SC determines not only the kinds of multisensory information that can be integrated in SC neurons, but the kinds of multisensory behaviors that SC neurons are able to mediate at different stages of development. MRDD Research Reviews 1999;5:72–85. © 1999 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Lignin is hypothesized to be a factor in the ability of cucurbits to resist fungal infection. To determine if lignin was present around sites of infection, susceptible cucumber plants and cucumber plants with systemic induced resistance were inoculated with Colletotnchum lagenanum, and the ultrastructure of plant and pathogen was examined 24 to 72 hours later. Conidia produced germ tubes with appressoria within 24 hours of inoculation on both control and induced plants. Penetration of plant epidermal cell walls occurred by 48 hours, and papillae formed at the site of penetration. Both elemental bromine and potassium permanganate were used to histochemically stain for lignin. Potassium permanganate, used together with energy dispersive X-ray microanalysis (EDS), indicated the presence of lignin in papillae and in electron-dense areas of plant cell walls directly beneath the appressoria. Using EDS, silicon was shown to be localized in the electron-dense areas of cucumber leaf cells. This is the first report of silicon in induced cucumber plants. There were no qualitative differences between the resistance reactions of induced and control plants. [ABSTRACT FROM AUTHOR]

Examines the possibility that auditory stimuli might alter the judgment of visual intensity in a manner consistent with what is known about the neural principles of multisensory integration. Dependence of the judgments of the stimulus' intensity on the level of central nervous system activity it generates; Convergence and integration of multiple sensory inputs.

Bacillus mycoides Ko01 strain grows rapidly and forms extensive rhizoidal colonies on hard agar despite limited surface water availability. The agar concentrations affect the handedness of the colonies as well as other colony architectures. In this study, we found that the local curvature of cell chains in the developing colonies did not vary based on the agar concentration, while concentration does affect the handedness of chirality at the macroscale. This result suggests independence between the microscale filament curvature and macroscale colony chirality. In addition, we discovered a novel microscopic property of cells that has not been observed before: T-shaped budding under extremely low surface water availability conditions. We propose that this feature gives rise to chaotic colony morphology. Together with bundling of chains, cells form a unique set of spatial arrangements under different surface water availability. These properties appear to impact the structural features of thick tendrils, and thereby the overall morphology of colonies. Our study provides additional insights as to how bacteria proliferate, spread, and develop macroscale colony architecture under water-limited conditions. [ABSTRACT FROM AUTHOR]

The diversity of our senses conveys many advantages; it enables them to compensate for one another when needed, and the information they provide about a common event can be integrated to facilitate its processing and, ultimately, adaptive responses. These cooperative interactions are produced by multisensory neurons. A well-studied model in this context is the multisensory neuron in the output layers of the superior colliculus (SC). These neurons integrate and amplify their cross-modal (e.g., visual-auditory) inputs, thereby enhancing the physiological salience of the initiating event and the probability that it will elicit SC-mediated detection, localization, and orientation behavior. Repeated experience with the same visual-auditory stimulus can also increase the neuron's sensitivity to these individual inputs. This observation raised the possibility that such plasticity could be engaged to restore visual responsiveness when compromised. For example, unilateral lesions of visual cortex compromise the visual responsiveness of neurons in the multisensory output layers of the ipsilesional SC and produces profound contralesional blindness (hemianopia). The possibility that multisensory plasticity could restore the visual responses of these neurons, and reverse blindness, was tested in the cat model of hemianopia. Hemianopic subjects were repeatedly presented with spatiotemporally congruent visual-auditory stimulus pairs in the blinded hemifield on a daily or weekly basis. After several weeks of this multisensory exposure paradigm, visual responsiveness was restored in SC neurons and behavioral responses were elicited by visual stimuli in the previously blind hemifield. The constraints on the effectiveness of this procedure proved to be the same as those constraining SC multisensory plasticity: whereas repetitions of a congruent visual-auditory stimulus was highly effective, neither exposure to its individual component stimuli, nor to these stimuli in non-congruent configurations was effective. The restored visual responsiveness proved to be robust, highly competitive with that in the intact hemifield, and sufficient to support visual discrimination. • Unilateral blindness can be rehabilitated by multisensory training. • Training stimuli must be arranged in spatiotemporally congruent assemblies. • The training protocol is effective in human and non-human animals. • The midbrain superior colliculus is believed to support recovered vision. [ABSTRACT FROM AUTHOR]

Despite ongoing screening efforts, colorectal cancer (CRC) remains a leading cause of death in Canada. The aim of this study was to better understand the experiences of Canadian CRC patients with their family practitioners (FPs) during and after their CRC diagnosis. Patient-reported data were collected through an online questionnaire to understand their CRC diagnosis experiences and identify potential gaps in care. Various factors contributing to challenges throughout a patient's CRC diagnosis (e.g., delayed CRC diagnosis) were determined using descriptive, qualitative, and inferential analyses. These factors could be targeted to optimize CRC care. This study found that 40.6% of the 175 respondents were unaware of at least one of the following aspects of CRC prior to their diagnosis: early-age onset (EAO), symptoms, and screening procedures. While 84.6% had access to a family physician (FP) before their diagnosis, only 17.7% were diagnosed by FPs. Higher proportions of younger individuals experienced misdiagnoses and felt dismissed compared to older individuals. Only half felt fully informed about their diagnosis when it was explained to them by their FP, while 53.1% had their diagnosis explained in plain language. Transitioning towards patient-centred care would promote pre-diagnosis CRC awareness, address differences in management of CRC care (e.g., dismissal and support), and accommodate for age and health-literacy-related disparities, thereby improving CRC care pathways for patients. Future research should investigate FPs experiences in detecting CRC cases to develop educational resources and recommendations, enhancing early detection and improving patient outcomes (1). [ABSTRACT FROM AUTHOR]

The incidence of early onset colorectal cancer (EOCRC) in Canada has increased. To address the growing incidence of EOCRC, Colorectal Cancer Canada (CCC) developed the Never Too Young (N2Y) program to identify gaps in care and evaluate patient and caregiver experiences with CRC. The survey was available online using SurveyMonkey across Canada between 12 December 2022 and 1 May 2023. The patient and caregiver survey consisted of 113 and 94 questions, respectively. A total of 108 EOCRC patients and 20 caregivers completed the survey. Many respondents were unaware of EOCRC (41.6%) and the disease symptoms (45.2%) before diagnosis. Patient age at diagnosis was between 45 and 50 years in 31.7%, and 72.8% of them were diagnosed at stage III or IV. A perception of an initial misdiagnosis was common (67.4%) for EOCRC patients, and 51.2% felt dismissed due to their age. Patients and caregivers reported impacts of EOCRC on their mental health, with 70.9% of patients expressing a need for support with depression and 93.3% of caregivers experiencing a constant fear of recurrence of their loved one's cancer. Improving the Canadian population's awareness of EOCRC (e.g., CRC symptoms) is important for ensuring timely diagnoses. Similarly, it is critical to ensure that healthcare providers are aware of the increase in EOCRC cases and the unique needs of these patients. Re-evaluation of the CRC screening age should be undertaken in Canada to determine whether lowering the start age to 45 years will improve outcomes in this demographic. [ABSTRACT FROM AUTHOR]

The superior colliculus (SC) is richly endowed with neurons that integrate cues from different senses to enhance their physiological responses and the overt behaviors they mediate. However, in the absence of experience with cross‐modal combinations (e.g., visual–auditory), they fail to develop this characteristic multisensory capability: Their multisensory responses are no greater than their most effective unisensory responses. Presumably, this impairment in neural development would be reflected as corresponding impairments in SC‐mediated behavioral capabilities such as detection and localization performance. Here, we tested that assumption directly in cats raised to adulthood in darkness. They, along with a normally reared cohort, were trained to approach brief visual or auditory stimuli. The animals were then tested with these stimuli individually and in combination under ambient light conditions consistent with their rearing conditions and home environment as well as under the opposite lighting condition. As expected, normally reared animals detected and localized the cross‐modal combinations significantly better than their individual component stimuli. However, dark‐reared animals showed significant defects in multisensory detection and localization performance. The results indicate that a physiological impairment in single multisensory SC neurons is predictive of an impairment in overt multisensory behaviors. [ABSTRACT FROM AUTHOR]

Here, flexible nanocomposites based on reduced graphene oxide (RGO) and commercial elastomers such as poly (acrylonitrile-ran-butadiene) (PANB) and poly (styrene-block-isoprene-block-styrene) (SIS) have been developed with enhanced electrical and mechanical properties due to the RGO fine dispersion. The RGO incorporation via stepwise addition resulted in well-dispersed RGO platelets in all polymer matrices. This allowed us to attain a comparatively low percolation threshold concentration (4.2 wt.% for all nanocomposites), at which the conductivity and current flow through the nanocomposites appreciably increased. The nanocomposite conductivity further increased with the increase of the RGO loading independently of the polymer type (PANB or SIS) or PANB molecular weight and acrylonitrile content. The highest conductivities obtained in this work are in the range 7.5–8.0 × 10–5 S/cm. Mechanical properties measured for SIS and PANB nanocomposites showed that tensile strength increases (in the case of SIS, by a factor of three) with the increase of the RGO content most likely due to physical crosslinking of the polymer with RGO. Improved electrical and mechanical properties of these nanocomposites make them promising as microwave absorbers or antistatic coatings. [ABSTRACT FROM AUTHOR]

Background: Low patient activation (PA) is associated with worse postoperative outcomes, however, its impact on the effectiveness of digital health interventions is unknown. We sought to determine the impact of PA on the effectiveness of digital health application for remote post-discharge follow-up for patients undergoing elective colectomy. Methods: Data analysis included a control cohort (CC) of patients undergoing elective colorectal surgery from 10/2017 to 04/2018 without the digital health intervention and a digital application cohort (DAC) that received a smart phone application for remote post-discharge follow-up from 03/2021 to 08/2022, including a subset of same-day discharge (SDD) patients. PA was measured using the Patient Activation Measure (PAM; score 0–100) and categorized into low (< 55.1) and high (≥ 55.1). The PAM was administered 4–6 weeks before surgery in the DAC group and on postoperative day (POD) 1 in the CC group. The main outcome measure was 30-day emergency department (ED) visits. Results: A total of 164 patients were included (89DAC with 50 SDD, 75CC), with no differences in patient characteristics other than more stoma closures in the DAC group. Overall, 77% of patients had high PA level, with no difference between CC and DAC (77% vs. 81%, p = 0.25). There was no difference in ED visits between CC and DAC (19% vs. 18%, p = 0.90). Overall, low PA was associated more ED visits (29% vs 14%, p = 0.04). In the SDD subgroup, low PA patients had more ED visits (38% vs. 7%, p = 0.015). PA level did not affect app usage metrics. On multiple regression, only low PA remained independently associated with ED visits (OR 3.42, 95%CI 1.27, 9.24). Conclusion: Low PA remains an important predictor of surgical outcomes after elective colorectal surgery regardless of the use of a digital health application for remote post-discharge follow-up. This suggests that improving PA levels may improve postoperative outcomes. [ABSTRACT FROM AUTHOR]

Canada has one of the most complex and rigorous drug approval and public reimbursement processes and is, unfortunately, one of the countries with the longest delays in drug access. To assess the overall impact of systemic delays in access to cancer therapy, a targeted literature review (TLR) was performed to identify studies associated with the clinical, economic, and quality of life impacts of delayed access to oncology drugs. Using MEDLINE/PubMed databases and snowballing, four unique records met the eligibility criteria. Results revealed that clinical outcomes were the most impacted by systemic delays in access to oncology drugs (e.g., life years lost, overall survival, and progression-free survival). The four articles retrieved by the TLR specifically illustrated that a substantial number of life years could potentially be saved by increasing systemic efficiency regarding the development, approval, and reimbursement processes of new drugs for advanced malignancies. It is imperative that initiatives are put in place to improve the performance and speed of Canadian drug regulatory and health technology assessment (HTA) processes, especially for new cancer therapeutics. The proposed solutions in this paper include better coordination between HTA and Canadian payers to harmonize coverage decisions, international collaborations, information sharing, and national standards for timeliness in oncology drug access. [ABSTRACT FROM AUTHOR]

Sleep difficulties are a common symptom in cancer patients at different stages of treatment trajectory and may lead to numerous negative consequences for which management is required. This pilot Randomized Controlled Trial (RCT) aims to assess the potential effectiveness of home-based prehabilitation intervention (prehab) on sleep quality and parameters compared to standard care (SOC) in colorectal cancer patients during the preoperative period and up to 8 weeks after the surgery. One hundred two participants (48.3% female, mean age 65 years) scheduled for elective resection of colorectal cancer were randomized to the prehab (n = 50) or the SOC (n = 52) groups. Recruitment and retention rates were 54% and 72%, respectively. Measures were completed at the baseline and preoperative, 4- and 8-week after-surgery follow-ups. Our mixed models' analyses revealed no significant differences between groups observed over time for all subjective and objective sleep parameters. A small positive change was observed in the perceived sleep quality only at the preoperative time point for the prehabilitation group compared to the SOC group, with an effect size d = 0.11 and a confidence interval (CI) between − 2.1 and − 0.1, p =.048. Prehab group patients with high anxiety showed a significant improvement in the rate of change of sleep duration over time compared to the SOC group, with a difference of 110 min between baseline and 8 weeks after surgery (d = 0.51, 95% CI: 92.3 to 127.7, p =.02). Multimodal prehabilitation intervention is feasible in colorectal cancer patients and may improve sleep duration for patients with high anxiety symptoms. Future large-scale RCTs are needed to confirm our results. [ABSTRACT FROM AUTHOR]

Abstract: Bilateral testis tumors are rare and the majority of cases are classic seminoma presenting metachronously. We present the only reported case of synchronous bilateral spermatocytic seminoma. [Copyright &y& Elsevier]

Presents updates on the Florida Bar Association's Lawyer Referral Service Committee. Duties and responsibilities; Meetings and seminars; Initiatives to promote the service.

The author discusses the use of personalized medicine in management of patients with colorectal cancer in Canada. The author states that personalized medicine helps form basis of a holistic, individualized approach to the management of the disease. The author notes that reimbursement process is the greatest threat to precision therapies. The author mentions that the full potential of personalized medicine can be reached if healthcare professionals bring about changes in health care delivery.

The COVID-19 pandemic caused disruptions in colorectal cancer (CRC) care by interrupting CRC screening across Canada, posing problems for program participants, patients, and physicians and no clear understanding of how provincial healthcare systems would adapt in the face of another pandemic or shock to the system. A nationwide online survey targeted to members of the National Colorectal Cancer Screening Network (NCCSN) using the SurveyMonkey platform was conducted to gain insight into the impact of the pandemic on CRC screening from March 2020 to March 2022 across all thirteen Canadian jurisdictions. The survey included 25 multiple-choice and free-text questions. Both quantitative and qualitative methods were used to analyze the data using Microsoft Excel and NVivo software. Twenty-one provincial and territorial representatives participated in the survey conducted between 13 May 2022 and 27 October 2022. All jurisdictions (100%) reported decreased screenings, including fecal immunochemical testing (FIT) or Fecal Occult Blood testing (FOBT) procedures, and subsequent diagnostic colonoscopies. The average wait time for colonoscopies due to a positive FIT/FOBT was 76 days. To mitigate the backlog and initiate an effective intervention plan, representatives highlighted some key points, including the importance of prioritizing high-risk patients. Survey results concluded that the COVID-19 pandemic impacted CRC screening across Canada. This landscape assessment can help inform intervention measures and policy-related solutions to create greater resilience for CRC screening in provincial and territorial healthcare systems. [ABSTRACT FROM AUTHOR]

Introduction: Guidelines recommend incorporation of more than 20 perioperative interventions within an enhanced recovery program (ERP). However, the impact of overall adherence to the pathway and the relative contribution of each intervention are unclear. The aim of this study was to estimate the extent to which adherence to ERP elements is associated with outcomes and identify key ERP elements predicting successful recovery following bowel resection.Methods: Prospectively collected data entered in a registry specifically designed for ERPs were reviewed. Patients undergoing elective bowel resection between 2012 and 2014 were treated within an ERP comprising 23 care elements. Primary outcome was successful recovery defined as the absence of complications, discharge by postoperative day 4 and no readmission. Secondary outcomes were length of hospital stay (LOS), 30-day morbidity, and severity (Comprehensive complication index, CCI, 0-100). Regression analyses were adjusted for potential confounders.Results: A total of 347 patients were included in the study. Median primary LOS was 4 days (IQR 3-7). Patients were adherent to median 18 (IQR 16-20) elements. A total of 156 (45 %) patients had successful recovery. Morbidity occurred in 175 (50 %) patients with median CCI 8.6 (IQR 0-22.6). There was a positive association between adherence and successful recovery (OR 1.39 for every additional element, p < 0.001), LOS (11 % reduction for every additional element, p < 0.001), 30-day postoperative morbidity (OR 0.78, p < 0.001), and the CCI (17 % reduction, p < 0.001). Laparoscopy (OR 4.32, p < 0.001), early mobilization out of bed (OR 2.25, p = 0.021), and early termination of IV fluid infusion (OR 2.00, p = 0.013) significantly predicted successful recovery. These factors were also associated with reduced morbidity and complication severity.Conclusions: Increased adherence to ERP interventions was associated with successful early recovery and a reduction in postoperative morbidity and complication severity. In an established ERP where overall adherence was high, laparoscopic approach, perioperative fluid management, and patient mobilization remain key elements associated with improved outcomes. [ABSTRACT FROM AUTHOR]

The multisensory integration capabilities of superior colliculus (SC) neurons are normally acquired during early postnatal life and adapted to the environment in which they will be used. Recent evidence shows that they can even be acquired in adulthood, and require neither consciousness nor any of the reinforcement contingencies generally associated with learning. This process is believed to be based on Hebbian mechanisms, whereby the temporal coupling of multiple sensory inputs initiates development of a means of integrating their information. This predicts that co-activation of those input channels is sufficient to induce multisensory integration capabilities regardless of the specific spatiotemporal properties of the initiating stimuli. However, one might expect that the stimuli to be integrated should be consonant with the functional role of the neurons involved. For the SC, this would involve stimuli that can be localized. Experience with a non-localizable cue in one modality (e.g., ambient sound) and a discrete stimulus in another (e.g., a light flash) should not be sufficient for this purpose. Indeed, experiments with cats reared in omnidirectional sound (effectively masking discrete auditory events) reveal that the simple co-activation of two sensory input channels is not sufficient for this purpose. The data suggest that experience with the kinds of cross-modal events that facilitate the role of the SC in detecting, locating, and orienting to localized external events is a guiding factor in this maturational process. Supported by NIH grants NS 036916 and EY016716. [ABSTRACT FROM AUTHOR]

In this article, the author discusses the study which examines subsequent auditory localization judgments using the after-effects of adaptations to visual-auditory stimuli. It states that the study revealed visual effects in patients whose conscious awareness of visual stimuli was compromised by unilateral lesions of straite cortex or parieto-temporal cortex. The author said that the present finding is a welcome contribution to the effort to the study of auditory localization.

A correction to the article "Multisensory integration: current issues from the perspective of the single neuron" that was published in the previous issue is presented.

Intravesical Bacillus Calmette-Guerin (BCG) is usually a well-tolerated treatment strategy for transitional cell cancer of the bladder. We report a patient with penile and bladder mucosal lesions with inguinal adenopathy after six instillations of intravesical BCG. Pathology demonstrated inflammation with granulomatous changes. The lesions and adenopathy resolved with antituberculous drug treatment. We describe the patient’s clinical presentation and review the complications of intravesical BCG treatment. [Copyright &y& Elsevier]

Background: There is increasing evidence to support discharge prior to gastrointestinal recovery following colorectal surgery. Furthermore, many patients are discharged early despite being excluded from an ambulatory colectomy pathway. The objective of this study was to determine the outcomes of patients discharged early following laparoscopic colectomy in an enhanced recovery pathway (ERP). Methods: A retrospective review of all adult patients undergoing elective laparoscopic colectomy at a single university-affiliated colorectal referral center (08/2017–06/2021) was performed. Patients were included if they had undergone elective laparoscopic colectomy or ileostomy closure and excluded if they had been enrolled in an ambulatory colectomy pathway. Patients were then divided into three groups: LOS =1 day, LOS 2–3 days, and LOS 4+ days. The main outcomes were 30-day emergency room (ER) visits and readmissions. Reasons for inpatient stay per post-operative day (POD) were also recorded. Results: A total of 497 patients were included [LOS1 n = 63 (13%), LOS2–3 n = 284 (57%), and LOS4+ n = 150 (30%)]. There were no differences in patient characteristics, diagnosis, or procedure between the groups. Patients were discharged with gastrointestinal recovery (GI-3) in 54% LOS1 vs. 98% LOS2–3 vs. 100% LOS4+ (p<0.001). Shorter procedure duration, transversus abdominus plane block, and lower opioid requirements were associated with shorter LOS (p<0.001). The absence of flatus was the most common reason to keep patients hospitalized: 61% on POD1, 21% on POD2, and 8% on POD3 (p<0.001). There were no differences in 30-day emergency visits, or readmission between the groups. In the LOS1 group, there were no differences in outcomes between patients with full return of bowel function at discharge compared to those without. Conclusion: Discharge on POD1 was not associated with increased emergency department use, complications, or readmissions. Importantly, full return of bowel function at discharge did not affect outcomes. There may be potential to expand eligibility criteria for ambulatory colectomy protocol. [ABSTRACT FROM AUTHOR]

Hemianopia (unilateral blindness), a common consequence of stroke and trauma to visual cortex, is a debilitating disorder for which there are few treatments. Research in an animal model has suggested that visual-auditory stimulation therapy, which exploits the multisensory architecture of the brain, may be effective in restoring visual sensitivity in hemianopia. It was tested in two male human patients who were hemianopic for at least 8 months following a stroke. The patients were repeatedly exposed to congruent visual-auditory stimuli within their blinded hemifield during 2 h sessions over several weeks. The results were dramatic. Both recovered the ability to detect and describe visual stimuli throughout their formerly blind field within a few weeks. They could also localize these stimuli, identify some of their features, and perceive multiple visual stimuli simultaneously in both fields. These results indicate that the multisensory therapy is a rapid and effective method for restoring visual function in hemianopia. [ABSTRACT FROM AUTHOR]

Introduction: A high proportion of colorectal surgery patients within an enhanced recovery pathway (ERP) do not experience complications but remain hospitalized mainly waiting for gastrointestinal (GI) recovery. Accurate identification of these patients may allow discharge prior to the return of GI function. Therefore, the objective of this study is to determine if tolerating clear fluid (CF) on postoperative day (POD) 0 was associated with uncomplicated return of GI function after laparoscopic colorectal surgery. Methods: Pooled data from three prospective studies from a single specialist colorectal referral center were analyzed (2013–2019). The present study included adult patients that underwent elective laparoscopic colectomy without stoma. Postoperative GI symptoms were collected daily in all three datasets. The main exposure variable, whether CF diet was tolerated on POD0, was defined as patients drinking at least 300 mL of CF without any nausea, anti-emetics, or vomiting (CF+ vs CF−). The main outcome measure was time to GI-3 (tolerating solid diet and passage of gas or stools). Results: A total of 221 patients were included in this study, including 69% CF+ and 31% CF−. The groups were similar in age, gender, and comorbidities, but the CF− patients were more likely to have surgery for inflammatory bowel disease. CF+ patients had faster time to GI-3 (mean 1.6d (SD 0.7) vs. 2.3d (SD 1.5), p < 0.001). The CF+ group also experienced fewer complications (19% vs. 35%, p = 0.009), shorter mean LOS (mean 3.6d (SD 2.9) vs. 6.2d (SD 9.4), p = 0.002), and were more likely to be discharged by the target LOS (66% vs. 50%, p = 0.024). Conclusion: Toleration of CF on POD0 was associated with faster return of GI function, fewer complications, and shorter LOS. This may be used as a criteria for potential discharge prior to full return of GI function after laparoscopic colectomy within an ERP. [ABSTRACT FROM AUTHOR]

Understanding the principles by which the brain combines information from different senses provides us with insight into the computational strategies used to maximize their utility. Prior studies of the superior colliculus (SC) neuron as a model suggest that the relative timing with which sensory cues appear is an important factor in this context. Cross-modal cues that are near-simultaneous are likely to be derived from the same event, and the neural inputs they generate are integrated more strongly than those from cues that are temporally displaced from one another. However, the present results from studies of cat SC neurons show that this "temporal principle" of multisensory integration is more nuanced than previously thought and reveal that the integration of temporally displaced sensory responses is also highly dependent on the relative efficacies with which they drive their common target neuron. Larger multisensory responses were achieved when stronger responses were advanced in time relative to weaker responses. This new temporal principle of integration suggests an inhibitory mechanism that better accounts for the sensitivity of the multisensory product to differences in the timing of cross-modal cues than do earlier mechanistic hypotheses based on response onset alignment or response overlap. [ABSTRACT FROM AUTHOR]