Artículos de revistas: "Sensory input"

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Bui, Tuan V. y Robert M. Brownstone. "Sensory-evoked perturbations of locomotor activity by sparse sensory input: a computational study". Journal of Neurophysiology 113, n.º 7 (abril de 2015): 2824–39. http://dx.doi.org/10.1152/jn.00866.2014.

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Sensory inputs from muscle, cutaneous, and joint afferents project to the spinal cord, where they are able to affect ongoing locomotor activity. Activation of sensory input can initiate or prolong bouts of locomotor activity depending on the identity of the sensory afferent activated and the timing of the activation within the locomotor cycle. However, the mechanisms by which afferent activity modifies locomotor rhythm and the distribution of sensory afferents to the spinal locomotor networks have not been determined. Considering the many sources of sensory inputs to the spinal cord, determining this distribution would provide insights into how sensory inputs are integrated to adjust ongoing locomotor activity. We asked whether a sparsely distributed set of sensory inputs could modify ongoing locomotor activity. To address this question, several computational models of locomotor central pattern generators (CPGs) that were mechanistically diverse and generated locomotor-like rhythmic activity were developed. We show that sensory inputs restricted to a small subset of the network neurons can perturb locomotor activity in the same manner as seen experimentally. Furthermore, we show that an architecture with sparse sensory input improves the capacity to gate sensory information by selectively modulating sensory channels. These data demonstrate that sensory input to rhythm-generating networks need not be extensively distributed.

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Santos, Bruno A., Rogerio M. Gomes, Xabier E. Barandiaran y Phil Husbands. "Active Role of Self-Sustained Neural Activity on Sensory Input Processing: A Minimal Theoretical Model". Neural Computation 34, n.º 3 (17 de febrero de 2022): 686–715. http://dx.doi.org/10.1162/neco_a_01471.

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Abstract A growing body of work has demonstrated the importance of ongoing oscillatory neural activity in sensory processing and the generation of sensorimotor behaviors. It has been shown, for several different brain areas, that sensory-evoked neural oscillations are generated from the modulation by sensory inputs of inherent self-sustained neural activity (SSA). This letter contributes to that strand of research by introducing a methodology to investigate how much of the sensory-evoked oscillatory activity is generated by SSA and how much is generated by sensory inputs within the context of sensorimotor behavior in a computational model. We develop an abstract model consisting of a network of three Kuramoto oscillators controlling the behavior of a simulated agent performing a categorical perception task. The effects of sensory inputs and SSAs on sensory-evoked oscillations are quantified by the cross product of velocity vectors in the phase space of the network under different conditions (disconnected without input, connected without input, and connected with input). We found that while the agent is carrying out the task, sensory-evoked activity is predominantly generated by SSA (93.10%) with much less influence from sensory inputs (6.90%). Furthermore, the influence of sensory inputs can be reduced by 10.4% (from 6.90% to 6.18%) with a decay in the agent's performance of only 2%. A dynamical analysis shows how sensory-evoked oscillations are generated from a dynamic coupling between the level of sensitivity of the network and the intensity of the input signals. This work may suggest interesting directions for neurophysiological experiments investigating how self-sustained neural activity influences sensory input processing, and ultimately affects behavior.

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Fadli, Muhammad, Wahyuni Wahyuni y Farid Rahman. "Penatalaksanaan Fisioterapi pada Pasien Diabetic Peripheral Neuropaty dengan Metode Sensorimotor Exercise". Ahmar Metastasis Health Journal 1, n.º 3 (31 de diciembre de 2021): 92–100. http://dx.doi.org/10.53770/amhj.v1i3.53.

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ABSTRACK Introduction:Diabetic peripheral neuropathy causes sensory disturbances such as the reduced sensation of vibration, pressure, pain, and joint position, this will result in reduced ability to balance and coordinate a person's gait. Sensory-motor exercise is used to correct muscle imbalances through sensory input. This study aims to determine the effect of exercise therapy on sensory improvement, balance, and functional ability using the sensory-motor exercise method in patients with diabetic peripheral neuropathy. The research method used in this study is an experiment with the case report method, and the sample is taken using an incidental technique. Results: After being given exercise therapy using the sensory-motor exercise method, the results were an increase in sensory input sensitivity, an increase in static balance, an increase in dynamic balance, and an increase in the patient's functional ability in the form of a better walking pattern. Conclusion: exercise therapy using the sensory-motor exercise method effectively improves balance and improves walking patterns in patients with diabetic peripheral neuropathy. Suggestion: exercise to increase the movement ability of sensory and functional functions can be combined with sensory training in patients with diabetic peripheral neuropathy. ABSTRAK Pendahuluan: Diabetic peripheral neuropati mengakibatkan gangguan sensorik seperti berkurangnya sensasi getaran, tekanan, nyeri dan posisi sendi, hal ini akan mengakibatkan berkurangnya kemampuan keseimbangan dan koordinasi gaya berjalan seseorang, sensory motor exercise merupakan metode latihan yang digunakan untuk memperbaiki ketidakseimbangan otot melalui input sensorik. Penelitian ini bertujuan untuk mengetahui efek terapi latihan terhadap perbaikan sensoris, keseimbangan dan kemampuan fungsional dengan menggunakan metode sensori motor exercise pada pasien dengan diabetic peripheral neuropaty. Metode penelitian yang digunakan pada studi ini merupakan eksperimen dengan metode case report, dan sampel di ambil dengan teknik insindental. Hasil: setelah diberikan terapi latihan dengan metode sensory motor exercise didapatkan hasil berupa peningkatan sensitifitas input sensorik, peningkatan keseimbangan statis dan peningkatan keseimbangan dinamis serta peningkatan dari kemampuan fungsional pasien berupa pola berjalan yang lebih baik. Kesimpulan: terapi latihan dengan metode sensory motor exercise efektif untuk meningkatkan keseimbangan dan memperbaiki pola berjalan pada pasien dengan diabetic peripheral neuropaty. Saran: latihan peningkatan kemampuan gerak fungsi sensoris dan fungsional dapat dikombinasikan dengan latihan sensomotori pada penderita diabetic peripheral neuropaty.

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Ugawa, Yoshikazu. "Sensory input and basal ganglia". Rinsho Shinkeigaku 52, n.º 11 (2012): 862–65. http://dx.doi.org/10.5692/clinicalneurol.52.862.

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Mao, Yu-Ting, Tian-Miao Hua y Sarah L. Pallas. "Competition and convergence between auditory and cross-modal visual inputs to primary auditory cortical areas". Journal of Neurophysiology 105, n.º 4 (abril de 2011): 1558–73. http://dx.doi.org/10.1152/jn.00407.2010.

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Sensory neocortex is capable of considerable plasticity after sensory deprivation or damage to input pathways, especially early in development. Although plasticity can often be restorative, sometimes novel, ectopic inputs invade the affected cortical area. Invading inputs from other sensory modalities may compromise the original function or even take over, imposing a new function and preventing recovery. Using ferrets whose retinal axons were rerouted into auditory thalamus at birth, we were able to examine the effect of varying the degree of ectopic, cross-modal input on reorganization of developing auditory cortex. In particular, we assayed whether the invading visual inputs and the existing auditory inputs competed for or shared postsynaptic targets and whether the convergence of input modalities would induce multisensory processing. We demonstrate that although the cross-modal inputs create new visual neurons in auditory cortex, some auditory processing remains. The degree of damage to auditory input to the medial geniculate nucleus was directly related to the proportion of visual neurons in auditory cortex, suggesting that the visual and residual auditory inputs compete for cortical territory. Visual neurons were not segregated from auditory neurons but shared target space even on individual target cells, substantially increasing the proportion of multisensory neurons. Thus spatial convergence of visual and auditory input modalities may be sufficient to expand multisensory representations. Together these findings argue that early, patterned visual activity does not drive segregation of visual and auditory afferents and suggest that auditory function might be compromised by converging visual inputs. These results indicate possible ways in which multisensory cortical areas may form during development and evolution. They also suggest that rehabilitative strategies designed to promote recovery of function after sensory deprivation or damage need to take into account that sensory cortex may become substantially more multisensory after alteration of its input during development.

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Henn, V. "Sensory Input Modifying Central Motor Actions". Stereotactic and Functional Neurosurgery 49, n.º 5 (1986): 251–55. http://dx.doi.org/10.1159/000100183.

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Franosch, Jan-Moritz P., Sebastian Urban y J. Leo van Hemmen. "Supervised Spike-Timing-Dependent Plasticity: A Spatiotemporal Neuronal Learning Rule for Function Approximation and Decisions". Neural Computation 25, n.º 12 (diciembre de 2013): 3113–30. http://dx.doi.org/10.1162/neco_a_00520.

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How can an animal learn from experience? How can it train sensors, such as the auditory or tactile system, based on other sensory input such as the visual system? Supervised spike-timing-dependent plasticity (supervised STDP) is a possible answer. Supervised STDP trains one modality using input from another one as “supervisor.” Quite complex time-dependent relationships between the senses can be learned. Here we prove that under very general conditions, supervised STDP converges to a stable configuration of synaptic weights leading to a reconstruction of primary sensory input.

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Etesami, Jalal y Philipp Geiger. "Causal Transfer for Imitation Learning and Decision Making under Sensor-Shift". Proceedings of the AAAI Conference on Artificial Intelligence 34, n.º 06 (3 de abril de 2020): 10118–25. http://dx.doi.org/10.1609/aaai.v34i06.6571.

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Learning from demonstrations (LfD) is an efficient paradigm to train AI agents. But major issues arise when there are differences between (a) the demonstrator's own sensory input, (b) our sensors that observe the demonstrator and (c) the sensory input of the agent we train.In this paper, we propose a causal model-based framework for transfer learning under such “sensor-shifts”, for two common LfD tasks: (1) inferring the effect of the demonstrator's actions and (2) imitation learning. First we rigorously analyze, on the population-level, to what extent the relevant underlying mechanisms (the action effects and the demonstrator policy) can be identified and transferred from the available observations together with prior knowledge of sensor characteristics. And we device an algorithm to infer these mechanisms. Then we introduce several proxy methods which are easier to calculate, estimate from finite data and interpret than the exact solutions, alongside theoretical bounds on their closeness to the exact ones. We validate our two main methods on simulated and semi-real world data.

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Havrylovych, Mariia y Valeriy Danylov. "Research of autoencoder-based user biometric verification with motion patterns". System research and information technologies, n.º 2 (30 de agosto de 2022): 128–36. http://dx.doi.org/10.20535/srit.2308-8893.2022.2.10.

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In the current research, we continue our previous study regarding motion-based user biometric verification, which consumes sensory data. Sensory-based verification systems empower the continuous authentication narrative – as physiological biometric methods mainly based on photo or video input meet a lot of difficulties in implementation. The research aims to analyze how various components of sensor data from an accelerometer affect and contribute to defining the process of unique person motion patterns and understanding how it may express the human behavioral patterns with different activity types. The study used the recurrent long-short-term-memory autoencoder as a baseline model. The choice of model was based on our previous research. The research results have shown that various data components contribute differently to the verification process depending on the type of activity. However, we conclude that a single sensor data source may not be enough for a robust authentication system. The multimodal authentication system should be proposed to utilize and aggregate the input streams from multiple sensors as further research.

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Stolz, Thomas, Max Diesner, Susanne Neupert, Martin E. Hess, Estefania Delgado-Betancourt, Hans-Joachim Pflüger y Joachim Schmidt. "Descending octopaminergic neurons modulate sensory-evoked activity of thoracic motor neurons in stick insects". Journal of Neurophysiology 122, n.º 6 (1 de diciembre de 2019): 2388–413. http://dx.doi.org/10.1152/jn.00196.2019.

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Neuromodulatory neurons located in the brain can influence activity in locomotor networks residing in the spinal cord or ventral nerve cords of invertebrates. How inputs to and outputs of neuromodulatory descending neurons affect walking activity is largely unknown. With the use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and immunohistochemistry, we show that a population of dorsal unpaired median (DUM) neurons descending from the gnathal ganglion to thoracic ganglia of the stick insect Carausius morosus contains the neuromodulatory amine octopamine. These neurons receive excitatory input coupled to the legs’ stance phases during treadmill walking. Inputs did not result from connections with thoracic central pattern-generating networks, but, instead, most are derived from leg load sensors. In excitatory and inhibitory retractor coxae motor neurons, spike activity in the descending DUM (desDUM) neurons increased depolarizing reflexlike responses to stimulation of leg load sensors. In these motor neurons, descending octopaminergic neurons apparently functioned as components of a positive feedback network mainly driven by load-detecting sense organs. Reflexlike responses in excitatory extensor tibiae motor neurons evoked by stimulations of a femur-tibia movement sensor either are increased or decreased or were not affected by the activity of the descending neurons, indicating different functions of desDUM neurons. The increase in motor neuron activity is often accompanied by a reflex reversal, which is characteristic for actively moving animals. Our findings indicate that some descending octopaminergic neurons can facilitate motor activity during walking and support a sensory-motor state necessary for active leg movements. NEW & NOTEWORTHY We investigated the role of descending octopaminergic neurons in the gnathal ganglion of stick insects. The neurons become active during walking, mainly triggered by input from load sensors in the legs rather than pattern-generating networks. This report provides novel evidence that octopamine released by descending neurons on stimulation of leg sense organs contributes to the modulation of leg sensory-evoked activity in a leg motor control system.

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Bell, C. C., V. Z. Han, Y. Sugawara y K. Grant. "Synaptic plasticity in the mormyrid electrosensory lobe". Journal of Experimental Biology 202, n.º 10 (15 de mayo de 1999): 1339–47. http://dx.doi.org/10.1242/jeb.202.10.1339.

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The mormyrid electrosensory lateral line lobe (ELL) is one of several different sensory structures in fish that behave as adaptive sensory processors. These structures generate negative images of predictable features in the sensory inflow which are added to the actual inflow to minimize the effects of predictable sensory features. The negative images are generated through a process of association between centrally originating predictive signals and sensory inputs from the periphery. In vitro studies in the mormyrid ELL show that pairing of parallel fiber input with Na+ spikes in postsynaptic cells results in synaptic depression at the parallel fiber synapses. The synaptic plasticity observed at the cellular level and the associative process of generating negative images of predicted sensory input at the systems level share a number of properties. Both are rapidly established, anti-Hebbian, reversible, input-specific and tightly restricted in time. These common properties argue strongly that associative depression at the parallel fiber synapse contributes to the adaptive generation of negative images in the mormyrid ELL.

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Ozdemir, Recep A. y Monica A. Perez. "Afferent input and sensory function after human spinal cord injury". Journal of Neurophysiology 119, n.º 1 (1 de enero de 2018): 134–44. http://dx.doi.org/10.1152/jn.00354.2017.

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Spinal cord injury (SCI) often disrupts the integrity of afferent (sensory) axons projecting through the spinal cord dorsal columns to the brain. Examinations of ascending sensory tracts, therefore, are critical for monitoring the extent of SCI and recovery processes. In this review, we discuss the most common electrophysiological techniques used to assess transmission of afferent inputs to the primary motor cortex (i.e., afferent input-induced facilitation and inhibition) and the somatosensory cortex [i.e., somatosensory evoked potentials (SSEPs), dermatomal SSEPs, and electrical perceptual thresholds] following human SCI. We discuss how afferent input modulates corticospinal excitability by involving cortical and spinal mechanisms depending on the timing of the effects, which need to be considered separately for upper and lower limb muscles. We argue that the time of arrival of afferent input onto the sensory and motor cortex is critical to consider in plasticity-induced protocols in humans with SCI. We also discuss how current sensory exams have been used to detect differences between control and SCI participants but might be less optimal to characterize the level and severity of injury. There is a need to conduct some of these electrophysiological examinations during functionally relevant behaviors to understand the contribution of impaired afferent inputs to the control, or lack of control, of movement. Thus the effects of transmission of afferent inputs to the brain need to be considered on multiple functions following human SCI.

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Raffi, Milena, Aurelio Trofè, Monica Perazzolo, Andrea Meoni y Alessandro Piras. "Sensory Input Modulates Microsaccades during Heading Perception". International Journal of Environmental Research and Public Health 18, n.º 6 (11 de marzo de 2021): 2865. http://dx.doi.org/10.3390/ijerph18062865.

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Microsaccades are small eye movements produced during attempted fixation. During locomotion, the eyes scan the environment; the gaze is not always directed to the focus of expansion of the optic flow field. We sought to investigate whether the microsaccadic activity was modulated by eye position during the view of radial optic flow stimuli, and if the presence or lack of a proprioceptive input signal may influence the microsaccade characteristics during self-motion perception. We recorded the oculomotor activity when subjects were either standing or sitting in front of a screen during the view of optic flow stimuli that simulated specific heading directions with different gaze positions. We recorded five trials of each stimulus. Results showed that microsaccade duration, peak velocity, and rate were significantly modulated by optic flow stimuli and trial sequence. We found that the microsaccade rate increased in each condition from trial 1 to trial 5. Microsaccade peak velocity and duration were significantly different across trials. The analysis of the microsaccade directions showed that the different combinations of optic flow and eye position evoked non-uniform directions of microsaccades in standing condition with mean vectors in the upper-left quadrant of the visual field, uncorrelated with optic flow directions and eye positions. In sitting conditions, all stimuli evoked uniform directions of microsaccades. Present results indicate that the proprioceptive signals when the subjects stand up creates a different input that could alter the eye-movement characteristics during heading perceptions.

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Louis, Matthieu, Thomas Huber, Richard Benton, Thomas P. Sakmar y Leslie B. Vosshall. "Bilateral olfactory sensory input enhances chemotaxis behavior". Nature Neuroscience 11, n.º 2 (23 de diciembre de 2007): 187–99. http://dx.doi.org/10.1038/nn2031.

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Fox, C. R., M. D. Lintal, S. S. Modesto y A. Owens. "Sensory input for real-world, controlled braking". Journal of Vision 3, n.º 9 (16 de marzo de 2010): 381. http://dx.doi.org/10.1167/3.9.381.

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SHERMAN, CARL. "Early Sensory Input Shapes Brain's Neural Structure". Clinical Psychiatry News 33, n.º 5 (mayo de 2005): 34. http://dx.doi.org/10.1016/s0270-6644(05)70350-7.

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Bastian, J. "Plasticity in an electrosensory system. I. General features of a dynamic sensory filter". Journal of Neurophysiology 76, n.º 4 (1 de octubre de 1996): 2483–96. http://dx.doi.org/10.1152/jn.1996.76.4.2483.

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1. In this study we describe changes in neuronal responses within the primary electrosensory processing nucleus of a weakly electric fish that occur when the fish are exposed to repetitive patterns of electrosensory stimuli. Extracellular single-unit recordings show that pyramidal cells within the electrosensory lateral line lobe develop, over a time course of several minutes, an insensitivity to repetitive stimuli applied to a cell's receptive field (local stimulus). The pyramidal cell response cancellation only develops if the local stimulus is applied simultaneously with a diffuse pattern of electrosensory stimulation that affects the entire fish, or with proprioceptive stimuli. 2. The mechanism by which responses to repetitive afferent inputs are canceled relies on the central generation of "negative image inputs" that provide increased inhibitory input to a cell's apical dendrites at times when excitatory afferent input is increased. The negative image input becomes excitatory when afferent excitation is reduced or when input from inhibitory interneurons is predominant. The integration of a specific pattern of receptor afferent input with the complementary negative image input results in strong attenuation of pyramidal cell responses. The negative image inputs are plastic, so that a single pyramidal cell can learn to reject a variety of afferent input patterns. 3. These electric fish commonly experience repetitive electrosensory signals as a result of changes in posture. Because the electric organ is located in the trunk and tail, cyclical movements associated with exploratory behaviors result in amplitude modulations (AMs) of the electric field, and these AMs alter electroreceptor afferent firing frequency but not the firing frequency of second-order pyramidal cells. The adaptive cancellation mechanism described in this study can account for the insensitivity of pyramidal cells to reafferent electrosensory stimulation caused by tail movements and other postural changes. 4. The tail movements generate proprioceptive as well as electrosensory inputs, and either of these signals alone provides sufficient information for the generation of negative image inputs. The size of the negative image is larger, however, if both inputs are active. 5. The synaptic plasticity underlying the development of negative image inputs has a long-term component; under appropriate conditions changes in synaptic efficacy persist for > 30 min. 6. Normally functioning glutamatergic synapses are necessary for the expression of the synaptic plasticity associated with this cancellation mechanism. The development of negative image responses is blocked by micropressure ejection of the glutamate antagonist 6,7-dinitroquinoxaline-2,3-dione into the neighborhood of the pyramidal cell apical dendrites. 7. The adaptive cancellation of repetitive inputs is based on anti-Hebbian mechanisms; that is, correlated pre- and postsynaptic activity lead to a reduction in the excitatory input provided by the plastic synapses. As has been shown for several other systems, the cancellation mechanism reduces the cells responses to reafferent patterns of sensory input. In addition, the results of this study indicate that the mechanism may be more general, enabling the system to also cancel patterns of input resulting from exogenous stimuli.

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Cattaneo, D. y J. Jonsdottir. "Sensory impairments in quiet standing in subjects with multiple sclerosis". Multiple Sclerosis Journal 15, n.º 1 (enero de 2009): 59–67. http://dx.doi.org/10.1177/1352458508096874.

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Balance disorders and falls are frequently observed in subjects with multiple sclerosis (MS). Along with motor impairment, sensory disorders and integration deficits of sensory inputs lead to inadequate motor responses. The assessment of these sensory disorders in an every day tasks, such as upright stance, increases our knowledge of postural control in this pathology, thus promoting more effective treatments. The aim of the study was to describe sensory impairments and sensory strategies in different sensory conditions. A stabilometric assessment was carried out in a consecutive convenience sample of 53 subjects. The age of the sample was 52.7 (21.1) years; the onset of pathology was 27.20 (14.5) years before the assessment. Balance was assessed in six sensory conditions. The impact of pathology on balance control was shown by the high percentage of abnormal scores: 75% of subjects with MS showed abnormal scores even in the eyes open condition. The alteration of a single sensory input led to an increase of abnormal scores in up to 82% of subjects. Almost all subjects showed abnormal scores in the vestibular conditions where 22% of them fell. The pattern of the subjects’ performance in the six sensory conditions suggests that balance control may be more correlated to the number of reliable sensory inputs than the nature of the sensory input itself.

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Marken, Richard S. y Brittany Horth. "When Causality Does Not Imply Correlation: More Spadework at the Foundations of Scientific Psychology". Psychological Reports 108, n.º 3 (junio de 2011): 943–54. http://dx.doi.org/10.2466/03.pr0.108.3.943-954.

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Experimental research in psychology is based on an open-loop causal model which assumes that sensory input causes behavioral output. This model was tested in a tracking experiment where participants were asked to control a cursor, keeping it aligned with a target by moving a mouse to compensate for disturbances of differing difficulty. Since cursor movements (inputs) are the only observable cause of mouse movements (outputs), the open-loop model predicts that there will be a correlation between input and output that increases as tracking performance improves. In fact, the correlation between sensory input and motor output is very low regardless of the quality of tracking performance; causality, in terms of the effect of input on output, does not seem to imply correlation in this situation. This surprising result can be explained by a closed-loop model which assumes that input is causing output while output is causing input.

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Yu, Yinghua, Laurentius Huber, Jiajia Yang, David C. Jangraw, Daniel A. Handwerker, Peter J. Molfese, Gang Chen, Yoshimichi Ejima, Jinglong Wu y Peter A. Bandettini. "Layer-specific activation of sensory input and predictive feedback in the human primary somatosensory cortex". Science Advances 5, n.º 5 (mayo de 2019): eaav9053. http://dx.doi.org/10.1126/sciadv.aav9053.

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When humans perceive a sensation, their brains integrate inputs from sensory receptors and process them based on their expectations. The mechanisms of this predictive coding in the human somatosensory system are not fully understood. We fill a basic gap in our understanding of the predictive processing of somatosensation by examining the layer-specific activity in sensory input and predictive feedback in the human primary somatosensory cortex (S1). We acquired submillimeter functional magnetic resonance imaging data at 7T (n = 10) during a task of perceived, predictable, and unpredictable touching sequences. We demonstrate that the sensory input from thalamic projects preferentially activates the middle layer, while the superficial and deep layers in S1 are more engaged for cortico-cortical predictive feedback input. These findings are pivotal to understanding the mechanisms of tactile prediction processing in the human somatosensory cortex.

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SUN, HAO, HANNAH E. SMITHSON, QASIM ZAIDI y BARRY B. LEE. "Do magnocellular and parvocellular ganglion cells avoid short-wavelength cone input?" Visual Neuroscience 23, n.º 3-4 (mayo de 2006): 441–46. http://dx.doi.org/10.1017/s0952523806233042.

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We recently developed a new technique to measure cone inputs to visual neurons and used this technique to seek short-wavelength-sensitive (S) cone inputs to parasol, magnocellular (MC) and midget, parvocellular (PC) ganglion cells. Here, we compare our physiological measurements of S-cone weights to those predicted by a random wiring model that assumes cells' receptive fields receive input from mixed cone types. The random wiring model predicts the average weights of S-cone input to be similar to the total percentage of S-cones but with considerable scatter, and the S-cone input polarity to be consistent with that of PC cells' surround and of MC cells' center. This is not consistent with our physiological measurements. We suggest that the ganglion cells' receptive fields may have a mechanism to avoid S-cone inputs, as is the case in the H1 horizontal cells. Previous reports of S-cone inputs, in particular substantial input to MC cells, are likely to reflect variation in prereceptoral filtering and/or the failure to correct for variation in macular pigment.

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Appelbaum, Lawrence G., David V. Smith, Carsten N. Boehler, Wen D. Chen y Marty G. Woldorff. "Rapid Modulation of Sensory Processing Induced by Stimulus Conflict". Journal of Cognitive Neuroscience 23, n.º 9 (septiembre de 2011): 2620–28. http://dx.doi.org/10.1162/jocn.2010.21575.

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Humans are constantly confronted with environmental stimuli that conflict with task goals and can interfere with successful behavior. Prevailing theories propose the existence of cognitive control mechanisms that can suppress the processing of conflicting input and enhance that of the relevant input. However, the temporal cascade of brain processes invoked in response to conflicting stimuli remains poorly understood. By examining evoked electrical brain responses in a novel, hemifield-specific, visual-flanker task, we demonstrate that task-irrelevant conflicting stimulus input is quickly detected in higher level executive regions while simultaneously inducing rapid, recurrent modulation of sensory processing in the visual cortex. Importantly, however, both of these effects are larger for individuals with greater incongruency-related RT slowing. The combination of neural activation patterns and behavioral interference effects suggest that this initial sensory modulation induced by conflicting stimulus inputs reflects performance-degrading attentional distraction because of their incompatibility rather than any rapid task-enhancing cognitive control mechanisms. The present findings thus provide neural evidence for a model in which attentional distraction is the key initial trigger for the temporal cascade of processes by which the human brain responds to conflicting stimulus input in the environment.

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TURKEWITZ, GERALD y PATRICIA A. KENNY. "The Role of Developmental Limitations of Sensory Input on Sensory/Perceptual Organization". Journal of Developmental & Behavioral Pediatrics 6, n.º 5 (octubre de 1985): 302???306. http://dx.doi.org/10.1097/00004703-198510000-00014.

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Creutzig, Felix y Henning Sprekeler. "Predictive Coding and the Slowness Principle: An Information-Theoretic Approach". Neural Computation 20, n.º 4 (abril de 2008): 1026–41. http://dx.doi.org/10.1162/neco.2008.01-07-455.

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Understanding the guiding principles of sensory coding strategies is a main goal in computational neuroscience. Among others, the principles of predictive coding and slowness appear to capture aspects of sensory processing. Predictive coding postulates that sensory systems are adapted to the structure of their input signals such that information about future inputs is encoded. Slow feature analysis (SFA) is a method for extracting slowly varying components from quickly varying input signals, thereby learning temporally invariant features. Here, we use the information bottleneck method to state an information-theoretic objective function for temporally local predictive coding. We then show that the linear case of SFA can be interpreted as a variant of predictive coding that maximizes the mutual information between the current output of the system and the input signal in the next time step. This demonstrates that the slowness principle and predictive coding are intimately related.

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Ishak, Shaziela, Andrea Bubka y Frederick Bonato. "Visual Occlusion Decreases Motion Sickness in a Flight Simulator". Perception 47, n.º 5 (28 de febrero de 2018): 521–30. http://dx.doi.org/10.1177/0301006618761336.

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Sensory conflict theories of motion sickness (MS) assert that symptoms may result when incoming sensory inputs (e.g., visual and vestibular) contradict each other. Logic suggests that attenuating input from one sense may reduce conflict and hence lessen MS symptoms. In the current study, it was hypothesized that attenuating visual input by blocking light entering the eye would reduce MS symptoms in a motion provocative environment. Participants sat inside an aircraft cockpit mounted onto a motion platform that simultaneously pitched, rolled, and heaved in two conditions. In the occluded condition, participants wore “blackout” goggles and closed their eyes to block light. In the control condition, participants opened their eyes and had full view of the cockpit’s interior. Participants completed separate Simulator Sickness Questionnaires before and after each condition. The posttreatment total Simulator Sickness Questionnaires and subscores for nausea, oculomotor, and disorientation in the control condition were significantly higher than those in the occluded condition. These results suggest that under some conditions attenuating visual input may delay the onset of MS or weaken the severity of symptoms. Eliminating visual input may reduce visual/nonvisual sensory conflict by weakening the influence of the visual channel, which is consistent with the sensory conflict theory of MS.

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26

Javanmard-Gh., A., D. Iwaszczuk y S. Roth. "DEEPLIO: DEEP LIDAR INERTIAL SENSOR FUSION FOR ODOMETRY ESTIMATION". ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences V-1-2021 (17 de junio de 2021): 47–54. http://dx.doi.org/10.5194/isprs-annals-v-1-2021-47-2021.

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Abstract. Having a good estimate of the position and orientation of a mobile agent is essential for many application domains such as robotics, autonomous driving, and virtual and augmented reality. In particular, when using LiDAR and IMU sensors as the inputs, most existing methods still use classical filter-based fusion methods to achieve this task. In this work, we propose DeepLIO, a modular, end-to-end learning-based fusion framework for odometry estimation using LiDAR and IMU sensors. For this task, our network learns an appropriate fusion function by considering different modalities of its input latent feature vectors. We also formulate a loss function, where we combine both global and local pose information over an input sequence to improve the accuracy of the network predictions. Furthermore, we design three sub-networks with different modules and architectures derived from DeepLIO to analyze the effect of each sensory input on the task of odometry estimation. Experiments on the benchmark dataset demonstrate that DeepLIO outperforms existing learning-based and model-based methods regarding orientation estimation and shows a marginal position accuracy difference.

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27

Bastian, Joseph. "Modulation of Calcium-Dependent Postsynaptic Depression Contributes to an Adaptive Sensory Filter". Journal of Neurophysiology 80, n.º 6 (1 de diciembre de 1998): 3352–55. http://dx.doi.org/10.1152/jn.1998.80.6.3352.

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Bastian, Joseph. Modulation of calcium-dependent postsynaptic depression contributes to an adaptive sensory filter. J. Neurophysiol. 80: 3352–3355, 1998. The ability of organisms to ignore unimportant patterns of sensory input may be as critical as the ability to attend to those that are behaviorally relevant. Mechanisms used to reject irrelevant inputs range from peripheral filters, which allow only restricted portions of the spectrum of possible inputs to pass, to higher-level processes, which actively select stimuli to be “attended to.” Recent studies of several lower vertebrates demonstrate the presence of adaptive sensory filters, which “learn,” with a time course of a few minutes, to cancel predictable patterns of sensory input without compromising responses to novel stimuli. Predictable stimuli include “reafferent” stimuli, which occur as a result of an animal's own activity, as well as stimuli that are simply repetitive. The adaptive characteristic of these filters depends on an anti-Hebbian form of synaptic plasticity that modulates the strength of multisensory dendritic inputs resulting in the genesis of “negative image” signals, which cancel the predicted pattern of sensory afference. This report provides evidence that the mechanism underlying the anti-Hebbian plasticity involves the modulation of a calcium-dependent form of postsynaptic depression.

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Freeman, Oliver J., Mathew H. Evans, Garth J. S. Cooper, Rasmus S. Petersen y Natalie J. Gardiner. "Thalamic amplification of sensory input in experimental diabetes". European Journal of Neuroscience 44, n.º 1 (30 de mayo de 2016): 1779–86. http://dx.doi.org/10.1111/ejn.13267.

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Luczak, A., P. Bartho y K. D. Harris. "Gating of Sensory Input by Spontaneous Cortical Activity". Journal of Neuroscience 33, n.º 4 (23 de enero de 2013): 1684–95. http://dx.doi.org/10.1523/jneurosci.2928-12.2013.

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30

Cottereau, B., J. Ales y A. Norcia. "Decoding the mismatch between expectation and sensory input". Journal of Vision 11, n.º 11 (23 de septiembre de 2011): 267. http://dx.doi.org/10.1167/11.11.267.

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HÉliot, R. y B. Espiau. "Multisensor Input for CPG-Based Sensory---Motor Coordination". IEEE Transactions on Robotics 24, n.º 1 (febrero de 2008): 191–95. http://dx.doi.org/10.1109/tro.2008.915433.

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32

Capobianco, Robyn A., Awad M. Almuklass y Roger M. Enoka. "Manipulation of sensory input can improve stretching outcomes". European Journal of Sport Science 18, n.º 1 (4 de noviembre de 2017): 83–91. http://dx.doi.org/10.1080/17461391.2017.1394370.

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Taub, Aryeh H. y Matti Mintz. "Amygdala conditioning modulates sensory input to the cerebellum". Neurobiology of Learning and Memory 94, n.º 4 (noviembre de 2010): 521–29. http://dx.doi.org/10.1016/j.nlm.2010.09.004.

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Rogers, Mark W., Daniel L. Wardman, Stephen R. Lord y Richard C. Fitzpatrick. "Passive tactile sensory input improves stability during standing". Experimental Brain Research 136, n.º 4 (19 de febrero de 2001): 514–22. http://dx.doi.org/10.1007/s002210000615.

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35

Livneh, Y., N. Feinstein, M. Klein y A. Mizrahi. "Sensory Input Enhances Synaptogenesis of Adult-Born Neurons". Journal of Neuroscience 29, n.º 1 (7 de enero de 2009): 86–97. http://dx.doi.org/10.1523/jneurosci.4105-08.2009.

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36

Cole, Jonathan. "On the Relation Between Sensory Input and Action". Journal of Motor Behavior 36, n.º 3 (septiembre de 2004): 243–44. http://dx.doi.org/10.3200/jmbr.36.3.243-244.

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37

Kilgard, Michael P., Pritesh K. Pandya, Navzer D. Engineer y Raluca Moucha. "Cortical network reorganization guided by sensory input features". Biological Cybernetics 87, n.º 5-6 (1 de diciembre de 2002): 333–43. http://dx.doi.org/10.1007/s00422-002-0352-z.

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38

Chen, H., BM Nigg, M. Hulliger y J. de Koning. "Influence of sensory input on plantar pressure distribution". Clinical Biomechanics 10, n.º 5 (julio de 1995): 271–74. http://dx.doi.org/10.1016/0268-0033(95)99806-d.

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ZANA, Y., D. F. VENTURA, J. M. de SOUZA y R. D. DeVOE. "Tetrachromatic input to turtle horizontal cells". Visual Neuroscience 18, n.º 5 (septiembre de 2001): 759–65. http://dx.doi.org/10.1017/s0952523801185093.

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Recent physiological experiments support behavioral and morphological evidence for a fourth type of cone in the turtle retina, maximally sensitive in the ultraviolet (UV). This cone type has not yet been included in the models proposed for connectivity between cones and horizontal cells. In this study, we examined the inputs of UV, S, M, and L cones to horizontal cells. We used the high-resolution Dynamic Constant Response Method to measure the spectral sensitivity of horizontal cells without background light and after adaptation to UV, blue (B), green (G), and red (R) light. We concluded the following: (1) Tetrachromatic input to a Y/B horizontal cell was identified. The spectral-sensitivity curves of the cell in three of the adaptation conditions were well represented by L-, M-, and S-cone functions. Adaptation to blue light revealed a peak at 372 nm, the same wavelength location as that determined behaviorally in the turtle. A porphyropsin template could be closely fitted to the sensitivity band in that region, strong evidence for input from a UV cone. (2) The spectral-sensitivity functions of R/G horizontal cells were well represented by the L- and M-cone functions. There was no indication of UV- or S-cone inputs into these cells. (3) The spectral sensitivities of the monophasic horizontal cells were dominated by the L cone. However, the shape of the spectral-sensitivity function depended on the background wavelength, indicating secondary M-cone input. Connectivity models of the outer retina that predict input from all cone types are supported by the finding of tetrachromatic input into Y/B horizontal cells. In contrast, we did not find tetrachromatic input to R/G and monophasic horizontal cells. Chromatic adaptation revealed the spectral-sensitivity function of the turtle UV cone peaking at 372 nm.

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Ludueña, Guillermo A. y Claudius Gros. "A Self-Organized Neural Comparator". Neural Computation 25, n.º 4 (abril de 2013): 1006–28. http://dx.doi.org/10.1162/neco_a_00424.

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Learning algorithms need generally the ability to compare several streams of information. Neural learning architectures hence need a unit, a comparator, able to compare several inputs encoding either internal or external information, for instance, predictions and sensory readings. Without the possibility of comparing the values of predictions to actual sensory inputs, reward evaluation and supervised learning would not be possible. Comparators are usually not implemented explicitly. Necessary comparisons are commonly performed by directly comparing the respective activities one-to-one. This implies that the characteristics of the two input streams (like size and encoding) must be provided at the time of designing the system. It is, however, plausible that biological comparators emerge from self-organizing, genetically encoded principles, which allow the system to adapt to the changes in the input and the organism. We propose an unsupervised neural circuitry, where the function of input comparison emerges via self-organization only from the interaction of the system with the respective inputs, without external influence or supervision. The proposed neural comparator adapts in an unsupervised form according to the correlations present in the input streams. The system consists of a multilayer feedforward neural network, which follows a local output minimization (anti-Hebbian) rule for adaptation of the synaptic weights. The local output minimization allows the circuit to autonomously acquire the capability of comparing the neural activities received from different neural populations, which may differ in population size and the neural encoding used. The comparator is able to compare objects never encountered before in the sensory input streams and evaluate a measure of their similarity even when differently encoded.

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Berberian, Nareg, Matt Ross y Sylvain Chartier. "Embodied working memory during ongoing input streams". PLOS ONE 16, n.º 1 (5 de enero de 2021): e0244822. http://dx.doi.org/10.1371/journal.pone.0244822.

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Sensory stimuli endow animals with the ability to generate an internal representation. This representation can be maintained for a certain duration in the absence of previously elicited inputs. The reliance on an internal representation rather than purely on the basis of external stimuli is a hallmark feature of higher-order functions such as working memory. Patterns of neural activity produced in response to sensory inputs can continue long after the disappearance of previous inputs. Experimental and theoretical studies have largely invested in understanding how animals faithfully maintain sensory representations during ongoing reverberations of neural activity. However, these studies have focused on preassigned protocols of stimulus presentation, leaving out by default the possibility of exploring how the content of working memory interacts with ongoing input streams. Here, we study working memory using a network of spiking neurons with dynamic synapses subject to short-term and long-term synaptic plasticity. The formal model is embodied in a physical robot as a companion approach under which neuronal activity is directly linked to motor output. The artificial agent is used as a methodological tool for studying the formation of working memory capacity. To this end, we devise a keyboard listening framework to delineate the context under which working memory content is (1) refined, (2) overwritten or (3) resisted by ongoing new input streams. Ultimately, this study takes a neurorobotic perspective to resurface the long-standing implication of working memory in flexible cognition.

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42

Suranthiran, Sugathevan y Suhada Jayasuriya. "Signal Conditioning With Memory-Less Nonlinear Sensors". Journal of Dynamic Systems, Measurement, and Control 126, n.º 2 (1 de junio de 2004): 284–93. http://dx.doi.org/10.1115/1.1766030.

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Proposed in this paper is an off-line signal conditioning scheme for memoryless nonlinear sensors. In most sensor designs, a linear input-output response is desired. However, nonlinearity is present in one form or another in almost all real sensors and therefore it is very difficult if not impossible to achieve a truly linear relationship. Often sensor nonlinearity is considered a disadvantage in sensory systems because it introduces distortion into the system. Due to the lack of efficient techniques to deal with the issues of sensor nonlinearity, primarily nonlinear sensors tend to be ignored. In this paper, it is shown that there are certain advantages of using nonlinear sensors and nonlinear distortion caused by sensor nonlinearity may be effectively compensated. A recursive algorithm utilizing certain characteristics of nonlinear sensor functions is proposed for the compensation of nonlinear distortion and sensor noise removal. A signal recovery algorithm that implements this idea is developed. Not having an accurate sensor model will result in errors and it is shown that the error can be minimized with a proper choice of a convergence accelerator whereby stability of the developed algorithm is established.

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43

Adetunla, Adedotun O., Olanrewaju Kolade, Adeyinka M. Adeoye y Saheed Akande. "Development of a Prototype Sensory Device as a Substitute for Single Sided Deaf People in Developing Nations". Journal Européen des Systèmes Automatisés 55, n.º 6 (31 de diciembre de 2022): 765–69. http://dx.doi.org/10.18280/jesa.550608.

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Hearing loss is the inability to hear sounds ranging from 20 decibels or more in one or both ears. It can affect one or both ears and leads to difficulty in hearing speech or sounds in general. Single-sided deafness or unilateral hearing loss is a very widespread disability. However, most people only see hearing loss as being a binary problem assuming that you either have perfect hearing in both ears or are completely deaf in both ears, and dismiss the other types of hearing loss. Sensory substitution involves remapping the information gathered by one sensory receptor to another. Sensory receptors regardless of the signals they receive or capture, all encode the gathered information as electrochemical signals. This biological property of sensory receptors, coupled with the human brain’s neuroplasticity allows sensory receptors to be substituted, giving rise to new methods of sensory perception. This study aims to develop a sensory device known as a localizer. The localizer detects sound using numerous sound sensors, and feeds the input to the microcontrollers which then use the input to control the eccentric mass motor by implementing various motor drivers. The results gotten from this prototype device shows great improvement in the ability of a single-sided deaf person to localize sound.

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44

Porr, Bernd y Paul Miller. "Forward propagation closed loop learning". Adaptive Behavior 28, n.º 3 (31 de mayo de 2019): 181–94. http://dx.doi.org/10.1177/1059712319851070.

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For an autonomous agent, the inputs are the sensory data that inform the agent of the state of the world, and the outputs are their actions, which act on the world and consequently produce new sensory inputs. The agent only knows of its own actions via their effect on future inputs; therefore desired states, and error signals, are most naturally defined in terms of the inputs. Most machine learning algorithms, however, operate in terms of desired outputs. For example, backpropagation takes target output values and propagates the corresponding error backwards through the network in order to change the weights. In closed loop settings, it is far more obvious how to define desired sensory inputs than desired actions, however. To train a deep network using errors defined in the input space would call for an algorithm that can propagate those errors forwards through the network, from input layer to output layer, in much the same way that activations are propagated. In this article, we present a novel learning algorithm which performs such ‘forward-propagation’ of errors. We demonstrate its performance, first in a simple line follower and then in a 1st person shooter game.

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45

Fitzgerald, Maria. "Patrick David Wall. 5 April 1925—8 August 2001". Biographical Memoirs of Fellows of the Royal Society 72 (diciembre de 2021): 371–88. http://dx.doi.org/10.1098/rsbm.2021.0014.

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Patrick (Pat) Wall was a neurophysiologist and true pioneer in the science of pain. He discovered that the sensory information arising from receptors in our body, such as those for touch and heat, could be modified, or ‘gated’, in the spinal cord by other sensory inputs and also by information descending from the brain; this meant, as is now well recognized, that the final sensory experience is not necessarily predictable from the original pain-eliciting sensory input. He used this to explain the poor relationship between injury and pain, and to illustrate the fallacy of judging what someone ‘should’ be feeling from the sensory input alone. In 1969, together with his colleague, Ron Melzack, Pat proposed the ‘gate control theory of pain’ and the circuit diagram that summarized how central spinal cord circuits can modulate sensory inputs. Later on, he began to regret that ‘goddamned diagram’, which had come to dominate his life and work, but, like all great models, it paved the way for the future. Now, over 50 years after it was first published, molecular genetic dissection of dorsal horn neuronal circuitry has indisputably confirmed that sensory inputs are indeed ‘gated’ in the spinal cord dorsal horn. Through a career that started with a medical degree in Oxford, followed by almost 20 years at Yale and MIT in the USA, and continued at University College London, Pat Wall was a highly influential, critical, creative and original thinker who revolutionized our understanding of the relationship between injury and pain, and who also became a champion for all who suffered from chronic pain.

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46

Ghose, Geoffrey M. "Attentional Modulation of Visual Responses by Flexible Input Gain". Journal of Neurophysiology 101, n.º 4 (abril de 2009): 2089–106. http://dx.doi.org/10.1152/jn.90654.2008.

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Although it is clear that sensory responses in the cortex can be strongly modulated by stimuli outside of classical receptive fields as well as by extraretinal signals such as attention and anticipation, the exact rules governing the neuronal integration of sensory and behavioral signals remain unclear. For example, most experiments studying sensory interactions have not explored attention, while most studies of attention have relied on the responses to relatively limited sets of stimuli. However, a recent study of V4 responses, in which location, orientation, and spatial attention were systematically varied, suggests that attention can both facilitate and suppress specific sensory inputs to a neuron according to behavioral relevance. To explore the implications of such input gain, we modeled the effects of a center-surround organization of attentional modulation using existing receptive field models of sensory integration. The model is consistent with behavioral measurements of a suppressive effect that surrounds the facilitatory locus of spatial attention. When this center-surround modulation is incorporated into realistic models of sensory integration, it is able to explain seemingly disparate observations of attentional effects in the neurophysiological literature, including spatial shifts in receptive field position and the preferential modulation of low contrast stimuli. The model is also consistent with recent formulations of attention to features in which gain is variably applied among cells with different receptive field properties. Consistent with functional imaging results, the model predicts that spatial attention effects will vary between different visual areas and suggests that attention may act through a common mechanism of selective and flexible gain throughout the visual system.

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47

Sparks, Daniel W. y C. Andrew Chapman. "Heterosynaptic modulation of evoked synaptic potentials in layer II of the entorhinal cortex by activation of the parasubiculum". Journal of Neurophysiology 116, n.º 2 (1 de agosto de 2016): 658–70. http://dx.doi.org/10.1152/jn.00095.2016.

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The superficial layers of the entorhinal cortex receive sensory and associational cortical inputs and provide the hippocampus with the majority of its cortical sensory input. The parasubiculum, which receives input from multiple hippocampal subfields, sends its single major output projection to layer II of the entorhinal cortex, suggesting that it may modulate processing of synaptic inputs to the entorhinal cortex. Indeed, stimulation of the parasubiculum can enhance entorhinal responses to synaptic input from the piriform cortex in vivo. Theta EEG activity contributes to spatial and mnemonic processes in this region, and the current study assessed how stimulation of the parasubiculum with either single pulses or short, five-pulse, theta-frequency trains may modulate synaptic responses in layer II entorhinal stellate neurons evoked by stimulation of layer I afferents in vitro. Parasubicular stimulation pulses or trains suppressed responses to layer I stimulation at intervals of 5 ms, and parasubicular stimulation trains facilitated layer I responses at a train-pulse interval of 25 ms. This suggests that firing of parasubicular neurons during theta activity may heterosynaptically enhance incoming sensory inputs to the entorhinal cortex. Bath application of the hyperpolarization-activated cation current (Ih) blocker ZD7288 enhanced the facilitation effect, suggesting that cholinergic inhibition of Ih may contribute. In addition, repetitive pairing of parasubicular trains and layer I stimulation induced a lasting depression of entorhinal responses to layer I stimulation. These findings provide evidence that theta activity in the parasubiculum may promote heterosynaptic modulation effects that may alter sensory processing in the entorhinal cortex.

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48

Dreher, B., A. Michalski, B. G. Cleland y W. Burke. "Effects of selective pressure block of Y-type optic nerve fibers on the receptive-field properties of neurons in area 18 of the visual cortex of the cat". Visual Neuroscience 9, n.º 1 (julio de 1992): 65–78. http://dx.doi.org/10.1017/s0952523800006374.

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AbstractRecordings were made from single neurons in area 18 of anesthetized cats (N2O/O2 mixture supplemented by continuous intravenous infusion of barbiturate) in which one optic nerve had been pressure blocked to selectively block conduction in the largest (Y-type) fibers. Cortical neurons were stimulated visually via the normal eye or via the eye with the pressure-blocked optic nerve (“Y-blocked eye”). Several properties of the receptive fields such as their spatial organization (S or C cells), orientation tuning, and the presence and strength of end-zone inhibition appear to be unaffected by removal of the Y input. By contrast, the removal of the Y input resulted in a small but significant reduction in the size of the discharge field and in the direction-selectivity index. In three respects, peak response discharge rate, eye dominance, and velocity sensitivity, removal of the Y input had strong and highly significant effects. Thus, the mean peak discharge frequency of responses evoked by the stimulation of binocular neurons via the Y-blocked eye was significantly lower than that of responses evoked by the stimulation via the normal eye. Accordingly, the eye-dominance histogram was shifted markedly towards the normal eye (more so than in the homologous experiment conducted on area 17 — Burke et al., 1992). Finally, the mean preferred velocity of responses of cells activated via the normal eye was in the vicinity of 145 deg/s, whereas for cells activated via the Y-blocked eye the value was about 35 deg/s. Overall, the results of the present study imply that (1) apart from Y-type excitatory input there are significant excitatory non-Y-inputs to area 18; these inputs at least partially consist of indirect X-type input relayed via area 17; (2) in neurons of area 18 that receive both Y-type and non-Y-type excitatory inputs, the Y-type input has a major influence on strength of the response and velocity sensitivity and a lesser influence on the direction selectivity and size of the discharge fields; and (3) area 18 contains mechanisms determining such receptive-field properties as S- or C-type organization, orientation tuning, and direction selectivity which can be accessed either by the Y input or by non-Y input.

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Antón-Bolaños, Noelia, Alejandro Sempere-Ferràndez, Teresa Guillamón-Vivancos, Francisco J. Martini, Leticia Pérez-Saiz, Henrik Gezelius, Anton Filipchuk, Miguel Valdeolmillos y Guillermina López-Bendito. "Prenatal activity from thalamic neurons governs the emergence of functional cortical maps in mice". Science 364, n.º 6444 (2 de mayo de 2019): 987–90. http://dx.doi.org/10.1126/science.aav7617.

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The mammalian brain’s somatosensory cortex is a topographic map of the body’s sensory experience. In mice, cortical barrels reflect whisker input. We asked whether these cortical structures require sensory input to develop or are driven by intrinsic activity. Thalamocortical columns, connecting the thalamus to the cortex, emerge before sensory input and concur with calcium waves in the embryonic thalamus. We show that the columnar organization of the thalamocortical somatotopic map exists in the mouse embryo before sensory input, thus linking spontaneous embryonic thalamic activity to somatosensory map formation. Without thalamic calcium waves, cortical circuits become hyperexcitable, columnar and barrel organization does not emerge, and the somatosensory map lacks anatomical and functional structure. Thus, a self-organized protomap in the embryonic thalamus drives the functional assembly of murine thalamocortical sensory circuits.

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Raz, C., D. Piper, R. Haller, H. Nicod, N. Dusart y A. Giboreau. "From sensory marketing to sensory design: How to drive formulation using consumers’ input?" Food Quality and Preference 19, n.º 8 (diciembre de 2008): 719–26. http://dx.doi.org/10.1016/j.foodqual.2008.04.003.

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