Статті в журналах: "Activation pattern"

1

Ravari, Reihaneh, and Hamid Reza Kobravi. "Identifying the Dynamics of Leg Muscle Activation During Human Gait Using Neural Oscillator and Fuzzy Compensator." International Clinical Neuroscience Journal 5, no. 3 (September 30, 2018): 106–12. http://dx.doi.org/10.15171/icnj.2018.21.

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Background: The goal of this study is to design a model in order to predict the muscle activation pattern because the muscle activation patterns contain valuable information about the muscle dynamics and movement patterns. Therefore, the goal of the presentation of this neural model is to identify the desired muscle activation patterns by Hopf chaotic oscillator during walking. Since the knee muscles activation has a significant effect on the movement pattern during walking, the main concentration of this study is to identify the knee muscles activation dynamics using a modeling technique. Methods: The electromyography (EMG) recording obtained from 5 healthy subjects that electrodes positioned on the tibialis-anterior (TA) and rectus femoris muscles on every 2 feet. In the proposed model, along with the chaotic oscillator, a fuzzy compensator was designed to face the unmolded dynamics. In fact, on the condition, the observed difference between the desired and actual activation patterns violate some specific quantitative ranges, the fuzzy compensator based on predefined rules modify the activity pattern produced by the Hopf oscillator. Results: Some quantitative measures used to evaluate the results. According to the achieved results, the proposed model could generate the trajectories, dynamics of which are similar to the muscle activation dynamics of the studied muscles. In this model, the generated activity pattern by the proposed model cannot follow the desired activity of the TA muscle as well as rectus femoris muscle. Conclusion: The similarity between the generated activity pattern by the model and the activation dynamics of Rectus- Femoris muscle was more in comparison with the similarity observed between activation pattern of Tibialis- Anterior and the pattern generated by the model. In other words, based on the recorded human data, the activation pattern of the Rectus- Femoris is more similar to a rhythmic pattern.

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2

Wohlert, Amy B., and Lisa Goffman. "Human Perioral Muscle Activation Patterns." Journal of Speech, Language, and Hearing Research 37, no. 5 (October 1994): 1032–40. http://dx.doi.org/10.1044/jshr.3705.1032.

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Task-dependent human motor organization in the perioral region was examined in eight normal adults who performed oral tasks including lip protrusion, chewing, and speech. Zero phase-lag correlations among EMG signals recorded from quadrants surrounding the lips were calculated in order to determine patterns of motor coupling. Results indicated that the perioral musculature is flexible in output organization. Activv in all quadrants was highly positively correlated during the protrusion task. During the chewing task, correlations were moderate, with a stronger pattern bilaterally across the upper and lower lips. The speech tasks showed lower levels of correlation among the quadrants, but again the pattern was more highly correlated bilaterally than ipsilaterally. Results are compared to studies of oral muscle innervation in humans and animals and also are related to hypotheses of cortical control patterns for oral movement.

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3

de Sá Pereira, Roberto Horácio. "Meaning Representationalism: between Representationalism and Qualia Realism." Grazer Philosophische Studien 93, no. 4 (November 7, 2016): 548–70. http://dx.doi.org/10.1163/18756735-09302005.

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The purpose of this article is to offer a new view of the key relation between the content and the conscious character of visual experience. The author aims to support the following claims. First, the author rejects the qualia realist claim that conscious character is an intrinsic, nonrepresentational property of visual experience, for example, a pattern of activation of neurons. However, the author also rejects the rival widespread representationalist claim that the conscious character of visual experience is identical to, or supervenes on, any specific property represented by visual experience. The positive proposal is the following. Conscious character is identical with those patterns of activation of neurons that are referentially or representationally alive. Conscious redness, for example, is a pattern of activations of neurons that is created normally only when brains of physical duplicates come in visual contact with some distal property and this pattern of activation is recruited by natural selection to represent that property. This is called meaning representationalism.

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4

Dibona, Gerald F., and Linda L. Sawin. "Functional significance of the pattern of renal sympathetic nerve activation." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 277, no. 2 (August 1, 1999): R346—R353. http://dx.doi.org/10.1152/ajpregu.1999.277.2.r346.

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To assess the renal functional significance of the pattern of renal sympathetic nerve activation, computer-generated stimulus patterns (delivered at constant integrated voltage) were applied to the decentralized renal sympathetic nerve bundle and renal hemodynamic and excretory responses determined in anesthetized rats. When delivered at the same integrated voltage, stimulus patterns resembling those observed in in vivo multifiber recordings of renal sympathetic nerve activity (diamond-wave patterns) produced greater renal vasoconstrictor responses than conventional square-wave patterns. Within diamond-wave patterns, increasing integrated voltage by increasing amplitude produced twofold greater renal vasoconstrictor responses than by increasing duration. With similar integrated voltages that were subthreshold for renal vasoconstriction, neither diamond- nor square-wave pattern altered glomerular filtration rate, whereas diamond- but not square-wave pattern reversibly decreased urinary sodium excretion by 25 ± 3%. At the same number of pulses per second, intermittent stimulation produced faster and greater renal vasoconstriction than continuous stimulation. At the same number of pulses per second, increases in rest period during intermittent stimulation proportionally augmented the renal vasoconstrictor response compared with that observed with continuous stimulation; the maximum augmentation of 55% occurred at a rest period of 500 ms. These results indicate that the pattern of renal sympathetic nerve stimulation (activity) significantly influences the rapidity, magnitude, and selectivity of the renal vascular and tubular responses.

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5

Lin, Jian-Zhi, Wen-Yu Chiu, Wei-Hsun Tai, Yu-Xiang Hong, and Chung-Yu Chen. "Ankle Muscle Activations during Different Foot-Strike Patterns in Running." Sensors 21, no. 10 (May 14, 2021): 3422. http://dx.doi.org/10.3390/s21103422.

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This study analysed the landing performance and muscle activity of athletes in forefoot strike (FFS) and rearfoot strike (RFS) patterns. Ten male college participants were asked to perform two foot strikes patterns, each at a running speed of 6 km/h. Three inertial sensors and five EMG sensors as well as one 24 G accelerometer were synchronised to acquire joint kinematics parameters as well as muscle activation, respectively. In both the FFS and RFS patterns, according to the intraclass correlation coefficient, excellent reliability was found for landing performance and muscle activation. Paired t tests indicated significantly higher ankle plantar flexion in the FFS pattern. Moreover, biceps femoris (BF) and gastrocnemius medialis (GM) activation increased in the pre-stance phase of the FFS compared with that of RFS. The FFS pattern had significantly decreased tibialis anterior (TA) muscle activity compared with the RFS pattern during the pre-stance phase. The results demonstrated that the ankle strategy focused on controlling the foot strike pattern. The influence of the FFS pattern on muscle activity likely indicates that an athlete can increase both BF and GM muscles activity. Altered landing strategy in cases of FFS pattern may contribute both to the running efficiency and muscle activation of the lower extremity. Therefore, neuromuscular training and education are required to enable activation in dynamic running tasks.

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6

Mitrushina, Maura, and John Stamm. "Task-induced differential cortical activation pattern." International Journal of Psychophysiology 17, no. 1 (June 1994): 15–23. http://dx.doi.org/10.1016/0167-8760(94)90051-5.

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7

Sharma, Meena, Shilpi Modi, Subash Khushu, and Manas K. Mandal. "Neural activation pattern in self-deceivers." Psychological Studies 55, no. 1 (March 2010): 71–76. http://dx.doi.org/10.1007/s12646-010-0008-3.

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8

Fernandes, Orlando, Liana Catrina Lima Portugal, Rita de Cássia S. Alves, Tiago Arruda-Sanchez, Eliane Volchan, Mirtes Garcia Pereira, Janaina Mourão-Miranda, and Letícia Oliveira. "How do you perceive threat? It’s all in your pattern of brain activity." Brain Imaging and Behavior 14, no. 6 (August 24, 2019): 2251–66. http://dx.doi.org/10.1007/s11682-019-00177-6.

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Abstract Whether subtle differences in the emotional context during threat perception can be detected by multi-voxel pattern analysis (MVPA) remains a topic of debate. To investigate this question, we compared the ability of pattern recognition analysis to discriminate between patterns of brain activity to a threatening versus a physically paired neutral stimulus in two different emotional contexts (the stimulus being directed towards or away from the viewer). The directionality of the stimuli is known to be an important factor in activating different defensive responses. Using multiple kernel learning (MKL) classification models, we accurately discriminated patterns of brain activation to threat versus neutral stimuli in the directed towards context but not during the directed away context. Furthermore, we investigated whether it was possible to decode an individual’s subjective threat perception from patterns of whole-brain activity to threatening stimuli in the different emotional contexts using MKL regression models. Interestingly, we were able to accurately predict the subjective threat perception index from the pattern of brain activation to threat only during the directed away context. These results show that subtle differences in the emotional context during threat perception can be detected by MVPA. In the directed towards context, the threat perception was more intense, potentially producing more homogeneous patterns of brain activation across individuals. In the directed away context, the threat perception was relatively less intense and more variable across individuals, enabling the regression model to successfully capture the individual differences and predict the subjective threat perception.

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9

Hicks, Robert A., Tonja Green, and Jerayr Haleblian. "The Thayer Scale Response Patterns of Type a and Type b College Students." Psychological Reports 65, no. 3_suppl2 (December 1989): 1167–70. http://dx.doi.org/10.2466/pr0.1989.65.3f.1167.

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Using Thayer's Activation-Deactivation Adjective Check List, the activation patterns of 95 Type A and 105 Type B college students were measured. The pattern of the group means suggests that Type A students are higher than Type B students on both energy and tension activation. When the responses of individuals were examined, the Type A students were 2.5 times more likely to exhibit this high activation pattern than was the case for the Type B students.

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10

Dai, Chenyun, and Xiaogang Hu. "Extracting and Classifying Spatial Muscle Activation Patterns in Forearm Flexor Muscles Using High-Density Electromyogram Recordings." International Journal of Neural Systems 29, no. 01 (January 10, 2019): 1850025. http://dx.doi.org/10.1142/s0129065718500259.

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The human hand is capable of producing versatile yet precise movements largely owing to the complex neuromuscular systems that control our finger movement. This study seeks to quantify the spatial activation patterns of the forearm flexor muscles during individualized finger flexions. High-density (HD) surface electromyogram (sEMG) signals of forearm flexor muscles were obtained, and individual motor units were decomposed from the sEMG. Both macro-level spatial patterns of EMG activity and micro-level motor unit distributions were used to systematically characterize the forearm flexor activation patterns. Different features capturing the spatial patterns were extracted, and the unique patterns of forearm flexor activation were then quantified using pattern recognition approaches. We found that the forearm flexor spatial activation during the ring finger flexion was mostly distinct from other fingers, whereas the activation patterns of the middle finger were least distinguishable. However, all the different activation patterns can still be classified in high accuracy (94–100%) using pattern recognition. Our findings indicate that the partial overlapping of neural activation can limit accurate identification of specific finger movement based on limited recordings and sEMG features, and that HD sEMG recordings capturing detailed spatial activation patterns at both macro- and micro-levels are needed.

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11

Timmer, Anjuli M., та Victor Nizet. "IKKβ/NF-κB and the miscreant macrophage". Journal of Experimental Medicine 205, № 6 (2 червня 2008): 1255–59. http://dx.doi.org/10.1084/jem.20081056.

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Macrophage activation relies on complex intracellular signaling processes that integrate the need for rapid inflammatory responses to pathogens with the need to resolve inflammation without permanent harm to normal tissues. Patterns of aberrant macrophage activation characterize and sustain disorders of chronic inflammation, infection, and cancer. New studies now show a role for the NF-κB activator IKKβ in promoting an alternative, immunosuppressive pattern of macrophage activation, which limits the cell's tumoricidal and bactericidal capacities. As cancers and pathogens may have evolved multiple mechanisms to manipulate macrophages for their own survival, is there anything we can do about it?

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12

Nugent, Marilee M., and Theodore E. Milner. "Segmental specificity in belly dance mimics primal trunk locomotor patterns." Journal of Neurophysiology 117, no. 3 (March 1, 2017): 1100–1111. http://dx.doi.org/10.1152/jn.00693.2016.

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Belly dance was used to investigate control of rhythmic undulating trunk movements in humans. Activation patterns in lumbar erector spinae muscles were recorded using surface electromyography at four segmental levels spanning T10 to L4. Muscle activation patterns for movement tempos of 2 Hz, 3 Hz, and as fast as possible (up to 6 Hz) were compared to test the hypothesis that frequency modulates muscle timing, causing pattern changes analogous to gait transitions. Groups of trained and untrained female subjects were compared to test the hypothesis that experience modifies muscle coordination patterns and the capacity for selective motion of spinal segments. Three distinct coordination patterns were observed. An ipsilateral simultaneous pattern (S) and a diagonal synergy (D) dominated at lower frequencies. The S pattern was selected most often by novices and resembled the standing wave of activation underlying the alternating lateral trunk bending in salamander trotting. At 2 Hz, most trained subjects selected the D pattern, suggesting a greater capacity for segmental specificity compared with untrained subjects. At 3–4 Hz, there emerged an asynchronous pattern (A) analogous to the rostral-caudal traveling wave in salamander and lamprey swimming. The neural networks and mechanisms identified in primitive vertebrates, such as chains of coupled oscillators and segmental crossed inhibitory connections, could explain the patterns observed in this study in humans. Training allows modification of these patterns, possibly through improved capacity for selectively exciting or inhibiting segmental pattern generators. NEW & NOTEWORTHY Belly dance provides a novel approach for studying spinal cord neural circuits. New evidence suggests that primitive locomotor circuits may be conserved in humans. Erector spinae activation patterns during the hip shimmy at different tempos are similar to those observed in salamander walking and swimming. As movement frequency increases, a sequential pattern similar to lamprey swimming emerges, suggesting that primal involuntary control mechanisms dominate in fast lateral rhythmic spine undulations even in humans.

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13

Horn, D., and M. Usher. "Parallel Activation of Memories in an Oscillatory Neural Network." Neural Computation 3, no. 1 (February 1991): 31–43. http://dx.doi.org/10.1162/neco.1991.3.1.31.

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We describe a feedback neural network whose elements possess dynamic thresholds. This network has an oscillatory mode that we investigate by measuring the activities of memory patterns as functions of time. We observe spontaneous and induced transitions between the different oscillating memories. Moreover, the network exhibits pattern segmentation, by oscillating between different memories that are included as a mixture in a constant input. The efficiency of pattern segmentation decreases strongly as the number of the input memories is increased. Using oscillatory inputs we observe resonance behavior.

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14

Leake, Isobel. "Specific pattern of microglial activation in PD." Nature Reviews Neurology 17, no. 1 (December 2, 2020): 2. http://dx.doi.org/10.1038/s41582-020-00443-y.

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15

Weder, B., and R. J. Seitz. "Deficient cerebral activation pattern in stroke recovery." NeuroReport 5, no. 4 (January 1994): 457–60. http://dx.doi.org/10.1097/00001756-199401120-00022.

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16

Berg, D. "Cerebral activation pattern in primary writing tremor." Journal of Neurology, Neurosurgery & Psychiatry 69, no. 6 (December 1, 2000): 780–86. http://dx.doi.org/10.1136/jnnp.69.6.780.

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17

Paasch, Uwe, Sonja Grunewald, Ashok Agarwal, and Hans-Jürgen Glandera. "Activation pattern of caspases in human spermatozoa." Fertility and Sterility 81 (March 2004): 802–9. http://dx.doi.org/10.1016/j.fertnstert.2003.09.030.

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18

Law, I., C. Svarer, and O. B. Paulson. "W72 The activation pattern during eye movements." Electroencephalography and Clinical Neurophysiology 99, no. 4 (October 1996): 394. http://dx.doi.org/10.1016/0013-4694(96)88688-3.

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19

Parmar, Harshit, Fred Davis, and Eric Walden. "Understanding the neurodynamic process of decision-making for mobile application downloading." PLOS ONE 17, no. 12 (December 7, 2022): e0278753. http://dx.doi.org/10.1371/journal.pone.0278753.

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In this article, we try to explore and understand the neurodynamics of the decision-making process for mobile application downloading. We begin the model development in a rather unorthodox fashion. Patterns of brain activation regions are identified, across participants, at different time instance of the decision-making process. Region-wise activation knowledge from previous studies is used to put together the entire process model like a cognitive jigsaw puzzle. We find that there are indeed a common dynamic set of activation patterns that are consistent across people and apps. That is to say that not only are there consistent patterns of activation there is a consistent change from one pattern to another across time as people make the app adoption decision. Moreover, this pattern is clearly different for decisions that end in adoption than for decisions that end with no adoption.

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20

Anguelov, Roumen, and Stephanus Marnus Stoltz. "Modelling of activator-inhibitor dynamics via nonlocal integral operators." Texts in Biomathematics 1 (December 28, 2017): 57. http://dx.doi.org/10.11145/texts.2017.12.233.

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This paper proposes application of nonlocal operators to represent the biological pattern formation mechanism of self-activation and lateral inhibition. The blue-green algae Anabaena is discussed as a model example. The patterns are determined by the kernels of the integrals representing the nonlocal operators. The emergence of patters when varying the size of the support of the kernels is numerically investigated.

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21

Powers, Randall K., Sherif M. ElBasiouny, W. Zev Rymer, and C. J. Heckman. "Contribution of intrinsic properties and synaptic inputs to motoneuron discharge patterns: a simulation study." Journal of Neurophysiology 107, no. 3 (February 2012): 808–23. http://dx.doi.org/10.1152/jn.00510.2011.

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Motoneuron discharge patterns reflect the interaction of synaptic inputs with intrinsic conductances. Recent work has focused on the contribution of conductances mediating persistent inward currents (PICs), which amplify and prolong the effects of synaptic inputs on motoneuron discharge. Certain features of human motor unit discharge are thought to reflect a relatively stereotyped activation of PICs by excitatory synaptic inputs; these features include rate saturation and de-recruitment at a lower level of net excitation than that required for recruitment. However, PIC activation is also influenced by the pattern and spatial distribution of inhibitory inputs that are activated concurrently with excitatory inputs. To estimate the potential contributions of PIC activation and synaptic input patterns to motor unit discharge patterns, we examined the responses of a set of cable motoneuron models to different patterns of excitatory and inhibitory inputs. The models were first tuned to approximate the current- and voltage-clamp responses of low- and medium-threshold spinal motoneurons studied in decerebrate cats and then driven with different patterns of excitatory and inhibitory inputs. The responses of the models to excitatory inputs reproduced a number of features of human motor unit discharge. However, the pattern of rate modulation was strongly influenced by the temporal and spatial pattern of concurrent inhibitory inputs. Thus, even though PIC activation is likely to exert a strong influence on firing rate modulation, PIC activation in combination with different patterns of excitatory and inhibitory synaptic inputs can produce a wide variety of motor unit discharge patterns.

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22

Valledor, Annabel F., Luís Arpa, Ester Sánchez-Tilló, Mònica Comalada, Cristina Casals, Jordi Xaus, Carme Caelles, Jorge Lloberas та Antonio Celada. "IFN-γ–mediated inhibition of MAPK phosphatase expression results in prolonged MAPK activity in response to M-CSF and inhibition of proliferation". Blood 112, № 8 (15 жовтня 2008): 3274–82. http://dx.doi.org/10.1182/blood-2007-11-123604.

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Abstract Macrophages have the capacity to proliferate in response to specific growth factors, such as macrophage-colony stimulating factor (M-CSF). In the presence of several cytokines and activating factors, macrophages undergo growth arrest, become activated, and participate in the development of an immune response. We have previously observed that activation of extracellularly regulated kinase 1/2 (ERK-1/2) is required for macrophage proliferation in response to growth factors. A short and early pattern of ERK activity correlated with the proliferative response. In contrast, slightly prolonged patterns of activity of these kinases were induced by signals that lead to macrophage activation and growth arrest. IFN-γ is the main endogenous Th1-type macrophage activator. Here we report that stimulation with IFN-γ prolongs the pattern of ERK activity induced by M-CSF in macrophages. These effects correlate with IFN-γ–mediated inhibition of the expression of several members of the MAPK phosphatase family, namely MKP-1, -2, and -4. Moreover, inhibition of MKP-1 expression using siRNA technology or synthetic inhibitors also led to elongated ERK activity and significant blockage of M-CSF–dependent proliferation. These data suggest that subtle changes in the time course of activity of members of the MAPK family contribute to the antiproliferative effects of IFN-γ in macrophages.

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23

Li, Li, Qi Jin, Derek J. Dosdall, Jian Huang, Steven M. Pogwizd, and Raymond E. Ideker. "Activation becomes highly organized during long-duration ventricular fibrillation in canine hearts." American Journal of Physiology-Heart and Circulatory Physiology 298, no. 6 (June 2010): H2046—H2053. http://dx.doi.org/10.1152/ajpheart.01196.2009.

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Little is known about the three-dimensional (3-D) intramural activation sequences during long-duration ventricular fibrillation (VF), including the role of the subendocardium and its Purkinje fibers (PFs) in long-duration VF maintenance. Our aim was to explore the mechanism of long-duration VF maintenance with 3-D electrical mapping. We recorded 10 min of electrically induced VF in the left ventricular anterior free wall of six 10-kg, open-chest dogs using a 3-D transmural unipolar electrode matrix (9 × 9 × 6, 2-mm spacing) that allowed us to map intramural activation sequences. At 2.5 ± 1.8 min of VF, although the body surface ECG continued to exhibit a disorganized VF pattern, intramurally a more organized, synchronous activation pattern was first observed [locally synchronized VF (LSVF)]. This pattern occurred one or more times in all dogs and was present 33.4 ± 31.4% of the time during 5–10 min of VF. As opposed to the preceding changing complex activation sequences of VF, during LSVF, wavefronts were large and highly repeatable near the endocardium, first exciting the endocardium almost simultaneously and then rapidly spreading toward the epicardium with different levels of conduction block en route. During LSVF, PF activations always preceded working myocardium activations near the endocardium. In conclusion, long-duration VF in dogs frequently becomes highly organized in the subendocardium, with activation fronts arising in this region and passing intramurally toward the epicardium, even though the surface ECG continues to exhibit a disorganized pattern. PFs appear to play an important role during this stage of VF.

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24

Osher, David E., James A. Brissenden, and David C. Somers. "Predicting an individual’s dorsal attention network activity from functional connectivity fingerprints." Journal of Neurophysiology 122, no. 1 (July 1, 2019): 232–40. http://dx.doi.org/10.1152/jn.00174.2019.

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The cortical dorsal attention network (DAN) is a set of parietal and frontal regions that support a wide variety of attentionally demanding tasks. Whereas attentional deployment reliably drives DAN activity across subjects, there is a large degree of variation in the activation pattern in individual subjects. We hypothesize that a subject’s own idiosyncratic pattern of cortical DAN activity can be predicted from that subject’s own unique pattern of functional connectivity. By modeling task activation as a function of whole brain connectivity patterns, we are able to define the connectivity fingerprints for the frontal and parietal DAN, and use it to predict a subject’s characteristic DAN activation pattern with high accuracy. These predictions outperform the standard group-average benchmark and predict a subject’s own activation pattern above and beyond predictions from another subject’s connectivity pattern. Thus an individual’s distinctive connectivity pattern accounts for substantial variance in DAN functional responses. Last, we show that the set of connections that predict cortical DAN responses, the frontal and parietal DAN connectivity fingerprints, is predominantly composed of other coactive regions, including regions outside of the DAN including occipital and temporal visual cortices. These connectivity fingerprints represent defining computational characteristics of the DAN, delineating which voxels are or are not capable of exerting top-down attentional bias to other regions of the brain. NEW & NOTEWORTHY The dorsal attention network (DAN) is a set of regions in frontoparietal cortex that reliably activate during attentional tasks. We designed computational models that predict the degree of an individual’s DAN activation using their resting-state connectivity pattern alone. This uncovered the connectivity fingerprints of the DAN, which define it so well that we can predict how a voxel will respond to an attentional task given only its pattern of connectivity, with outstanding accuracy.

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Tang, Jie, Qian Su, Xue Zhang, Wen Qin, Huaigui Liu, Meng Liang, and Chunshui Yu. "Brain Gene Expression Pattern Correlated with the Differential Brain Activation by Pain and Touch in Humans." Cerebral Cortex 31, no. 7 (March 10, 2021): 3506–21. http://dx.doi.org/10.1093/cercor/bhab028.

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Abstract Genes involved in pain and touch sensations have been studied extensively, but very few studies have tried to link them with neural activities in the brain. Here, we aimed to identify genes preferentially correlated to painful activation patterns by linking the spatial patterns of gene expression of Allen Human Brain Atlas with the pain-elicited neural responses in the human brain, with a parallel, control analysis for identification of genes preferentially correlated to tactile activation patterns. We identified 1828 genes whose expression patterns preferentially correlated to painful activation patterns and 411 genes whose expression patterns preferentially correlated to tactile activation pattern at the cortical level. In contrast to the enrichment for astrocyte and inhibitory synaptic transmission of genes preferentially correlated to tactile activation, the genes preferentially correlated to painful activation were mainly enriched for neuron and opioid- and addiction-related pathways and showed significant overlap with pain-related genes identified in previous studies. These findings not only provide important evidence for the differential genetic architectures of specific brain activation patterns elicited by painful and tactile stimuli but also validate a new approach to studying pain- and touch-related genes more directly from the perspective of neural responses in the human brain.

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Buchsbaum, Bradley R., Sabrina Lemire-Rodger, Candice Fang, and Hervé Abdi. "The Neural Basis of Vivid Memory Is Patterned on Perception." Journal of Cognitive Neuroscience 24, no. 9 (September 2012): 1867–83. http://dx.doi.org/10.1162/jocn_a_00253.

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When we have a rich and vivid memory for a past experience, it often feels like we are transported back in time to witness once again this event. Indeed, a perfect memory would exactly mimic the experiential quality of direct sensory perception. We used fMRI and multivoxel pattern analysis to map and quantify the similarity between patterns of activation evoked by direct perception of a diverse set of short video clips and the vivid remembering, with closed eyes, of these clips. We found that the patterns of distributed brain activation during vivid memory mimicked the patterns evoked during sensory perception. Using whole-brain patterns of activation evoked by perception of the videos, we were able to accurately classify brain patterns that were elicited when participants tried to vividly recall those same videos. A discriminant analysis of the activation patterns associated with each video revealed a high degree (explaining over 80% of the variance) of shared representational similarity between perception and memory. These results show that complex, multifeatured memory involves a partial reinstatement of the whole pattern of brain activity that is evoked during initial perception of the stimulus.

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Missig, Galen, James O. Robbins, Emery L. Mokler, Kenneth M. McCullough, Staci D. Bilbo, Christopher J. McDougle, and William A. Carlezon. "Sex-dependent neurobiological features of prenatal immune activation via TLR7." Molecular Psychiatry 25, no. 10 (January 4, 2019): 2330–41. http://dx.doi.org/10.1038/s41380-018-0346-4.

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Abstract Immune activation during pregnancy via infection or autoimmune disease is a risk factor for neuropsychiatric illness. Mouse models of prenatal immune activation often involve maternal administration of agents that activate toll-like receptors (TLRs), a class of pattern recognition receptors that initiate innate immune responses. Such studies have focused primarily on activating the TLR3 or TLR4 subtypes, to mimic immune responses to viral or bacterial infections, respectively. Here, we characterize the effects of prenatal activation of TLR7, which is implicated in the pathogenesis of autoimmune disease. Prenatal TLR7 activation via administration of the selective agonist imiquimod (5.0 mg/kg) induces a phenotype in offspring characterized by reduced anxiety-like behavior, fragmented social behavior, and altered ultrasonic vocalization patterns at 6–12 weeks of age. The characteristics of this phenotype are readily distinguishable from—and in some ways opposite to—those seen following prenatal activation of TLR3 and/or TLR4. Prenatal TLR7-activated mice have normal baseline locomotor activity, but are hyperresponsive to stimuli including social partners, circadian cues, and gonadal hormone fluctuations. These alterations are accompanied by decreases in microglia density but increases in ramifications. RNA-sequencing of dorsal striatum, a region showing profound changes in microglial markers, indicates that prenatal TLR7 activation induces differential expression of hundreds of genes at 13 weeks of age, with virtually no overlap in differentially expressed genes between males and females. Our findings demonstrate that prenatal immune activation can promote a wide range of developmental trajectories, depending on the type and/or pattern of TLR activation and the sex of the offspring.

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Gordon, Ian T., Mary J. Dunbar, Kimberly J. Vanneste, and Patrick J. Whelan. "Interaction Between Developing Spinal Locomotor Networks in the Neonatal Mouse." Journal of Neurophysiology 100, no. 1 (July 2008): 117–28. http://dx.doi.org/10.1152/jn.00829.2007.

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At birth, thoracosacral spinal cord networks in mouse can produce a coordinated locomotor-like pattern. In contrast, less is known about the cervicothoracic networks that generate forelimb locomotion. Here we show that cervical networks can produce coordinated rhythmic patterns in the brain stem-spinal cord preparation of the mouse. Segmentally the C5 and C8 neurograms were each found to be alternating left-right, and the ipsilateral C5 and C8 neurograms also alternated. Collectively these patterns were suggestive of locomotor-like activity. This pattern was not dependent on the presence of thoracosacral segments because they could be evoked following a complete transection of the spinal cord at T5. We next demonstrated that activation of thoracosacral networks either pharmacologically or by stimulation of sacrocaudal afferents could produce rhythmic activity within the C5 and C8 neurograms. On the other hand, pharmacological activation of cervical networks did not evoke alternating cervical rhythmic activity either in isolated cervicothoracic or -sacral preparations. Under these conditions, we found that activation of cervicothoracic networks could alter the timing of thoracosacral locomotor-like patterns. When thoracosacral networks were not activated pharmacologically but received rhythmic drive from cervicothoracic networks, a pattern of slow bursts with superimposed fast synchronous oscillations became the dominant lumbar neurogram pattern. Our data suggest that in neonatal mice the cervical CPG is capable of producing coordinated rhythmic patterns in the absence of input from lumbar segments, but caudorostral drive contributes to cervical patterns and rhythm stability.

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Kostraba, Britt, Yi-Ning Wu, Pei-Chun Kao, Caroline Stark, Sheng-Che Yen, and Jinsook Roh. "Muscle activation pattern during self-propelled treadmill walking." Journal of Physical Therapy Science 30, no. 8 (2018): 1069–72. http://dx.doi.org/10.1589/jpts.30.1069.

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30

Hirschmueller, Anja, Heiner Baur, Steffen Müller, Hans-Hermann Dickhuth, and Frank Mayer. "Neuromuscular Activation Pattern In Runners With Achilles Tendinopathy." Medicine & Science in Sports & Exercise 37, Supplement (May 2005): S312. http://dx.doi.org/10.1249/00005768-200505001-01623.

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Hirschmueller, Anja, Heiner Baur, Steffen M??ller, Hans-Hermann Dickhuth, and Frank Mayer. "Neuromuscular Activation Pattern In Runners With Achilles Tendinopathy." Medicine & Science in Sports & Exercise 37, Supplement (May 2005): S312. http://dx.doi.org/10.1097/00005768-200505001-01623.

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Miller, John M., Alden H. Harken, W. Clark Hargrove, and Mark E. Josephson. "Pattern of endocardial activation during sustained ventricular tachycardia." Journal of the American College of Cardiology 6, no. 6 (December 1985): 1280–87. http://dx.doi.org/10.1016/s0735-1097(85)80214-x.

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Brennan, Kiva, and Andrew G. Bowie. "Activation of host pattern recognition receptors by viruses." Current Opinion in Microbiology 13, no. 4 (August 2010): 503–7. http://dx.doi.org/10.1016/j.mib.2010.05.007.

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34

Segonzac, Cécile, and Cyril Zipfel. "Activation of plant pattern-recognition receptors by bacteria." Current Opinion in Microbiology 14, no. 1 (February 2011): 54–61. http://dx.doi.org/10.1016/j.mib.2010.12.005.

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Bolton, Thomas A. W., Constantin Tuleasca, Diana Wotruba, Gwladys Rey, Herberto Dhanis, Baptiste Gauthier, Farnaz Delavari, et al. "TbCAPs: A toolbox for co-activation pattern analysis." NeuroImage 211 (May 2020): 116621. http://dx.doi.org/10.1016/j.neuroimage.2020.116621.

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Mondal, Pritish, Mutasim Abu-Hasan, Abhishek Saha, Teresa Pitts, Melanie Rose, Donald C. Bolser, and Paul W. Davenport. "Effect of laparotomy on respiratory muscle activation pattern." Physiological Reports 4, no. 1 (January 2016): e12668. http://dx.doi.org/10.14814/phy2.12668.

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Sharma, Dinesh, Kumar Narayanan, Michael Shehata, and Charles Swerdlow. "Isthmus-dependent atrial flutter with unusual activation pattern." Heart Rhythm 11, no. 8 (August 2014): 1484–86. http://dx.doi.org/10.1016/j.hrthm.2014.04.034.

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38

BRENNEIS, C., W. N. LÖSCHER, K. E. EGGER, T. BENKE, M. SCHOCKE, M. F. GABL, G. WECHSELBERGER, et al. "Cortical Motor Activation Patterns Following Hand Transplantation and Replantation." Journal of Hand Surgery 30, no. 5 (October 2005): 530–33. http://dx.doi.org/10.1016/j.jhsb.2005.05.012.

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We studied cortical activation patterns by functional MRI in a patient who received bilateral hand transplantation after amputation 6 years ago and in a patient who had received unilateral hand replantation within 2 hours after amputation. In the early postoperative period, the patient who had had the hand transplantation revealed strong activation of a higher motor area, only weak activation of the primary sensorimotor motor cortex and no activation of the primary somatosensory cortex. At 1-year follow-up, a small increase in primary sensorimotor motor cortex activation was observed. Activation of the primary somatosensory cortex was only seen at the 2 year follow-up. By contrast, after hand replantation, the activation pattern was similar to that of the uninjured hand within 6 weeks. This included activation of the primary sensorimotor motor cortex, higher motor areas and primary somatosensory cortex. Transplantation after long-standing amputation results in cortical reorganization occurring over a 2-year period. In contrast, hand replantation within a few hours preserves a normal activation pattern.

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39

Koh, Young-Sang. "Pattern-recognition receptors and recognition of pathogens." Journal of Medicine and Life Science 6, no. 3 (June 1, 2009): 148–51. http://dx.doi.org/10.22730/jmls.2009.6.3.148.

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The mammalian host has evolved innate immune strategies to detect and respond to rapidly to diverse group of microorganisms. Microbial recognition is achieved by pattern-recognition receptors (PRRs) such as toll-like receptors (TLRs) and Nod-like receptor (NLRs). PRRs detect pathogen-associated molecular patterns (PAMPs) and activate downstream signalling pathways. NLRs have been proposed thal these cytosolic proteins regulate the cysteine protease caspase-1 within a multiprotein complex known as the inflammasome. Activation of caspase-1 leads to the cleavage and activation of proinflammatory cytokines such as interleukin-1β (lL-1β) and IL-18.

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40

Horak, F. B., and L. M. Nashner. "Central programming of postural movements: adaptation to altered support-surface configurations." Journal of Neurophysiology 55, no. 6 (June 1, 1986): 1369–81. http://dx.doi.org/10.1152/jn.1986.55.6.1369.

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We studied the extent to which automatic postural actions in standing human subjects are organized by a limited repertoire of central motor programs. Subjects stood on support surfaces of various lengths, which forced them to adopt different postural movement strategies to compensate for the same external perturbations. We assessed whether a continuum or a limited set of muscle activation patterns was used to produce different movement patterns and the extent to which movement patterns were influenced by prior experience. Exposing subjects standing on a normal support surface to brief forward and backward horizontal surface perturbations elicited relatively stereotyped patterns of leg and trunk muscle activation with 73- to 110-ms latencies. Activity began in the ankle joint muscles and then radiated in sequence to thigh and then trunk muscles on the same dorsal or ventral aspect of the body. This activation pattern exerted compensatory torques about the ankle joints, which restored equilibrium by moving the body center of mass forward or backward. This pattern has been termed the ankle strategy because it restores equilibrium by moving the body primarily around the ankle joints. To successfully maintain balance while standing on a support surface short in relation to foot length, subjects activated leg and trunk muscles at similar latencies but organized the activity differently. The trunk and thigh muscles antagonistic to those used in the ankle strategy were activated in the opposite proximal-to-distal sequence, whereas the ankle muscles were generally unresponsive. This activation pattern produced a compensatory horizontal shear force against the support surface but little, if any, ankle torque. This pattern has been termed the hip strategy, because the resulting motion is focused primarily about the hip joints. Exposing subjects to horizontal surface perturbations while standing on support surfaces intermediate in length between the shortest and longest elicited more complex postural movements and associated muscle activation patterns that resembled ankle and hip strategies combined in different temporal relations. These complex postural movements were executed with combinations of torque and horizontal shear forces and motions of ankle and hip joints. During the first 5-20 practice trials immediately following changes from one support surface length to another, response latencies were unchanged. The activation patterns, however, were complex and resembled the patterns observed during well-practiced stance on surfaces of intermediate lengths.(ABSTRACT TRUNCATED AT 400 WORDS)

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Deban, S. M., and U. Dicke. "Motor control of tongue movement during prey capture in plethodontid salamanders." Journal of Experimental Biology 202, no. 24 (December 15, 1999): 3699–714. http://dx.doi.org/10.1242/jeb.202.24.3699.

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Four species of salamander of the family Plethodontidae were examined using electromyographic (EMG) recording during prey-capture behavior to test the hypotheses that the tongue retractor, tongue protractor and jaw depressor muscles are activated simultaneously and in a stereotyped pattern, as was found in other salamanders, and to determine whether species with different tongue morphologies and tongue protraction abilities exhibit different motor control strategies. The results show that sequential activation was observed far more frequently than simultaneous activation; the jaw depressor muscle was activated first, followed by the tongue protractor and then the tongue retractor. Species with short, attached tongues (Desmognathus quadramaculatus and Plethodon jordani) showed simultaneous activation more often than species with long, free tongues (Pseudotriton ruber and Hydromantes supramontis), which showed strongly non-simultaneous activation. Most EMG variables showed no effect of prey-capture success, suggesting that sensory feedback is not involved in modulating the motor pattern during the prey-capture strike. Hydromantes supramontis was examined for modulation of its motor pattern in response to prey distance, and several EMG variables were found to be positively correlated with tongue protraction distance. The motor pattern of strongly non-simultaneous activation of antagonistic tongue muscles has evolved along with the evolution of long, free tongues in plethodontids. The variable motor patterns observed provide further evidence that amphibian feeding in general is not as highly stereotyped as has been previously thought.

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Karimi, Hamed, Haniyeh Marefat, Mahdiyeh Khanbagi, Chris Kalafatis, Mohammad Hadi Modarres, Zahra Vahabi, and Seyed-Mahdi Khaligh-Razavi. "Temporal dynamics of animacy categorization in the brain of patients with mild cognitive impairment." PLOS ONE 17, no. 2 (February 23, 2022): e0264058. http://dx.doi.org/10.1371/journal.pone.0264058.

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Electroencephalography (EEG) has been commonly used to measure brain alterations in Alzheimer’s Disease (AD). However, reported changes are limited to those obtained from using univariate measures, including activation level and frequency bands. To look beyond the activation level, we used multivariate pattern analysis (MVPA) to extract patterns of information from EEG responses to images in an animacy categorization task. Comparing healthy controls (HC) with patients with mild cognitive impairment (MCI), we found that the neural speed of animacy information processing is decreased in MCI patients. Moreover, we found critical time-points during which the representational pattern of animacy for MCI patients was significantly discriminable from that of HC, while the activation level remained unchanged. Together, these results suggest that the speed and pattern of animacy information processing provide clinically useful information as a potential biomarker for detecting early changes in MCI and AD patients.

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43

Ros, Jacqueline, Luc Pellerin, Fulvio Magara, Julien Dauguet, Françoise Schenk, and Pierre J. Magistretti. "Metabolic Activation Pattern of Distinct Hippocampal Subregions during Spatial Learning and Memory Retrieval." Journal of Cerebral Blood Flow & Metabolism 26, no. 4 (August 31, 2005): 468–77. http://dx.doi.org/10.1038/sj.jcbfm.9600208.

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Activation dynamics of hippocampal subregions during spatial learning and their interplay with neocortical regions is an important dimension in the understanding of hippocampal function. Using the (14C)-2-deoxyglucose autoradiographic method, we have characterized the metabolic changes occurring in hippocampal subregions in mice while learning an eight-arm radial maze task. Autoradiogram densitometry revealed a heterogeneous and evolving pattern of enhanced metabolic activity throughout the hippocampus during the training period and on recall. In the early stages of training, activity was enhanced in the CA1 area from the intermediate portion to the posterior end as well as in the CA3 area within the intermediate portion of the hippocampus. At later stages, CA1 and CA3 activations spread over the entire longitudinal axis, while dentate gyrus (DG) activation occurred from the anterior to the intermediate zone. Activation of the retrosplenial cortex but not the amygdala was also observed during the learning process. On recall, only DG activation was observed in the same anterior part of the hippocampus. These results suggest the existence of a functional segmentation of the hippocampus, each subregion being dynamically but also differentially recruited along the acquisition, consolidation, and retrieval process in parallel with some neocortical sites.

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44

Speed, Haley E., and Lynn E. Dobrunz. "Developmental Decrease in Short-Term Facilitation at Schaffer Collateral Synapses in Hippocampus Is mGluR1 Sensitive." Journal of Neurophysiology 99, no. 2 (February 2008): 799–813. http://dx.doi.org/10.1152/jn.00625.2007.

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Developmental changes can occur in the dynamic properties of synapses, known as short-term plasticity. Using rat acute hippocampal slices at room temperature, we have previously shown a decrease in short-term facilitation at Schaffer collateral synapses from young adults compared with juveniles in response to temporally complex natural stimulus patterns such as synapses receive in vivo. Here we show that this developmental decrease in facilitation is also seen at 32°C and investigate the underlying mechanism. Addition of the mGluR1 antagonist LY367385 increases short-term facilitation in response to the natural stimulus pattern, showing that mGluR1 is activated by synaptically released glutamate. Although synaptic activation of mGluR1 occurs at both ages, the effect is larger in young adults. Furthermore, blocking mGluR1 eliminates most of the developmental decrease in short-term facilitation during the natural stimulus pattern. We investigated possible retrograde/downstream messengers involved after synaptic activation of mGluR1. Blocking cannabinoid receptors has no effect on the response during the natural stimulus pattern, indicating that the reduction in facilitation during synaptic activation of mGluR1 does not occur through release of endocannabinoids. We find that blocking GABAB receptors increases facilitation during the natural stimulus pattern and occludes the effect of the mGluR1 antagonist, indicating a role for the modulation of GABA release from inhibitory interneurons by mGluR1 activation. These data suggest a model where synaptic activation of mGluR1 on inhibitory interneurons causes an increase in GABA release by inhibitory interneurons, which activates GABAB receptors on Schaffer collateral synapses and inhibits short-term facilitation during the natural stimulus pattern.

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45

Xiang, Zhong, Yujia Shen, Zhitao Cheng, Miao Ma, and Feng Lin. "Periodic Pattern Detection of Printed Fabric Based on Deep Learning Algorithm." Journal of Physics: Conference Series 2148, no. 1 (January 1, 2022): 012013. http://dx.doi.org/10.1088/1742-6596/2148/1/012013.

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Abstract Printed fabric patterns contain multiple repeat pattern primitives, which have a significant impact on fabric pattern design in the textile industry. The pattern primitive is often composed of multiple elements, such as color, form, and texture structure. Therefore, the more pattern elements it contains, the more complex the primitive is. In order to segment fabric primitives, this paper proposes a novel convolutional neural network (CNN) method with spatial pyramid pooling module as a feature extractor, which enables to learn the pattern feature information and determine whether the printed fabric has periodic pattern primitives. Furthermore, by choosing pair of activation peaks in a filter, a set of displacement vectors can be calculated. The activation peaks that are most accordant with the optimum displacement vector contribute to pick out the final size of primitives. The results show that the method with the powerful feature extraction capabilities of the CNN can segment the periodic pattern primitives of complex printed fabrics. Compared with the traditional algorithm, the proposed method has higher segmentation accuracy and adaptability.

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46

Ding, Jun, Anthony S. Wexler, and Stuart A. Binder-Macleod. "Development of a mathematical model that predicts optimal muscle activation patterns by using brief trains." Journal of Applied Physiology 88, no. 3 (March 1, 2000): 917–25. http://dx.doi.org/10.1152/jappl.2000.88.3.917.

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Because muscles must be repetitively activated during functional electrical stimulation, it is desirable to identify the stimulation pattern that produces the most force. Previous experimental work has shown that the optimal pattern contains an initial high-frequency burst of pulses (i.e., an initial doublet or triplet) followed by a low, constant-frequency portion. Pattern optimization is particularly challenging, because a muscle's contractile characteristics and, therefore, the optimal pattern change under different physiological conditions and are different for each person. This work describes the continued development and testing of a mathematical model that predicts isometric forces from fresh and fatigued muscles in response to brief trains of electrical pulses. By use of this model and an optimization algorithm, stimulation patterns that produced maximum forces from each subject were identified.

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Albarrán-Juárez, Julián, Andras Iring, ShengPeng Wang, Sayali Joseph, Myriam Grimm, Boris Strilic, Nina Wettschureck, Till F. Althoff, and Stefan Offermanns. "Piezo1 and Gq/G11 promote endothelial inflammation depending on flow pattern and integrin activation." Journal of Experimental Medicine 215, no. 10 (September 7, 2018): 2655–72. http://dx.doi.org/10.1084/jem.20180483.

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The vascular endothelium is constantly exposed to mechanical forces, including fluid shear stress exerted by the flowing blood. Endothelial cells can sense different flow patterns and convert the mechanical signal of laminar flow into atheroprotective signals, including eNOS activation, whereas disturbed flow in atheroprone areas induces inflammatory signaling, including NF-κB activation. How endothelial cells distinguish different flow patterns is poorly understood. Here we show that both laminar and disturbed flow activate the same initial pathway involving the mechanosensitive cation channel Piezo1, the purinergic P2Y2 receptor, and Gq/G11-mediated signaling. However, only disturbed flow leads to Piezo1- and Gq/G11-mediated integrin activation resulting in focal adhesion kinase-dependent NF-κB activation. Mice with induced endothelium-specific deficiency of Piezo1 or Gαq/Gα11 show reduced integrin activation, inflammatory signaling, and progression of atherosclerosis in atheroprone areas. Our data identify critical steps in endothelial mechanotransduction, which distinguish flow pattern-dependent activation of atheroprotective and atherogenic endothelial signaling and suggest novel therapeutic strategies to treat inflammatory vascular disorders such as atherosclerosis.

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Gallardo-Moreno, Geisa B., Andrés A. González-Garrido, Esteban Gudayol-Ferré, and Joan Guàrdia-Olmos. "Type 1 Diabetes Modifies Brain Activation in Young Patients While Performing Visuospatial Working Memory Tasks." Journal of Diabetes Research 2015 (2015): 1–9. http://dx.doi.org/10.1155/2015/703512.

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In recent years, increasing attention has been paid to the effects of Type 1 Diabetes (T1D) on cognitive functions. T1D onset usually occurs during childhood, so it is possible that the brain could be affected during neurodevelopment. We selected young patients of normal intelligence with T1D onset during neurodevelopment, no complications from diabetes, and adequate glycemic control. The purpose of this study was to compare the neural BOLD activation pattern in a group of patients with T1Dversushealthy control subjects while performing a visuospatial working memory task. Sixteen patients and 16 matched healthy control subjects participated. There was no significant statistical difference in behavioral performance between the groups, but, in accordance with our hypothesis, results showed distinct brain activation patterns. Control subjects presented the expected activations related to the task, whereas the patients had greater activation in the prefrontal inferior cortex, basal ganglia, posterior cerebellum, and substantia nigra. These different patterns could be due to compensation mechanisms that allow them to maintain a behavioral performance similar to that of control subjects.

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Torres, Gonzalo, David Chorro, Archit Navandar, Javier Rueda, Luís Fernández, and Enrique Navarro. "Assessment of Hamstring: Quadriceps Coactivation without the Use of Maximum Voluntary Isometric Contraction." Applied Sciences 10, no. 5 (February 29, 2020): 1615. http://dx.doi.org/10.3390/app10051615.

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This study aimed to study the coactivation patterns of the hamstring and quadriceps muscle groups during submaximal strength exercises commonly used in injury prevention in soccer without the use of maximum voluntary isometric contraction testing. This was used to compare: (i) the inter-limb differences in muscle activation; (ii) the intra-muscular group activation pattern and (iii) the activation pattern during different phases of the exercise. Muscle activation was recorded by surface electromyography in 19 elite, male, youth soccer players. Participants performed the following: Bulgarian squat, lunge and squat. Electrical activity was recorded for the rectus femoris, vastus medialis, vastus lateralis, biceps femoris and semitendinosus. No significant inter-limb differences were found (F1, 13 = 619; p = 0.82; η2 = 0.045). Significant differences were found in the muscle activation between individual muscles within the quadriceps and hamstrings muscle group for each of the exercises: Bulgarian squat (F1,18 = 331: p < 0.001; η2 = 0.80), lunge (F4,72 = 114.5; p < 0.001; η2 = 0.86) and squat (F1,16 = 247.31; p < 0.001; η2 = 0.93). Differences were found between the different phases of each of the exercises (F2,26 = 52.27; p = 0.02; η2 = 0.80). The existence of an activation pattern of each of the muscles in the three proposed exercises could be used for muscle assessment and as a tool for reconditioning post-injury.

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Vidhya, L., S. Saranya, and S. Poonguzhali. "Analysis of Lower Extremity Muscle Activation Using EMG." Applied Mechanics and Materials 573 (June 2014): 797–802. http://dx.doi.org/10.4028/www.scientific.net/amm.573.797.

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Electromyography (EMG) has been widely used as a tool to understand and distinguish between normal and pathological gait. This study aims at understanding the activation patterns of lower limb muscles viz. Gastrocnemius and Tibialis Anterior in the dominant leg of subjects with normal (n=5) as well as pathological (n=2) gait patterns. The paper presents a normative pattern of these muscles during normal walking condition from which the deviation of affected group from the control group is observed. For this analysis, Surface EMG signals along with Force Sensitive Resistor values are acquired. These surface EMG signals picked up during the muscle activity are interfaced with a PC via EMG acquisition system. The acquired signals were processed and analyzed which can be used for rehabilitative therapy planning.

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