Articles de revues : « "training latencies" »

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Stankovic, Ivana, Nela Ilic, Tihomir Ilic, Ljiljana Jelicic, Mirjana Sovilj, Vesna Martic, Silvana Punisic et Miodrag Stokic. « Sensorimotor rhythm neurofeedback training and auditory perception ». Vojnosanitetski pregled, n^o 00 (2022) : 33. http://dx.doi.org/10.2298/vsp210902033s.

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Background/Aim. This study aimed to investigate the effect of sensorimotor rhythm (SMR) (12-15 Hz) neurofeedback (NFB) training on auditory cognition measured by achievement on the QuickSIN test, changes in the amplitudes and latencies of evoked potentials in auditory oddball discrimination task and changes in the spectral power of the sensorimotor rhythm. Methods. Each of 16 healthy participants aged 25-40 years (8 male) had 20 daily sessions of SMR neurofeedback training. Auditory cognitive functions and electrophysiological correlates of cognitive processing were recorded 5 times: before NFB, after 5, 10, and 20 sessions, and one month after the last session. Results. The results showed a statistically significant decrease in N200 and P300 latencies at Fz, Cz, and Pz regions, improvement on the QuickSIN test and increase in EEG SMR rhythm spectral power in Cz region as a result of NFB SMR training. No significant effect of NFB training on the amplitude of N100, N200 and P300 on Fz, Cz and Pz was found. Conclusion.The obtained results suggest that sensorimotor rhythm training (SMR) neurofeedback (NFB) affects auditory perception in terms of shorter latencies of evoked potentials and better performance on QuickSIN test.

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Choi, Chul-Hee, et Hea-Sung Cho. « Effect of Music Training on Auditory Brainstem and Middle Latency Responses ». Audiology and Speech Research 16, n^o 1 (31 janvier 2020) : 41–47. http://dx.doi.org/10.21848/asr.190098.

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Purpose: The auditory system has potentials to reorganize its structure and function in response to environmental changes such as training, experience, learning, injury, and disease. This is called neuroplasticity. A typical example of neuroplasticity is the music training, which demands cognitive and neural challenges resulting in enhanced auditory perception. This study investigated the effect of music training on auditory evoked responses, particularly auditory brainstem and middle latency responses. Methods: Forty college students consisting of twenty students with music training (musicians) and twenty students without music training (non-musicians) participated in the study. All participants have normal ranges in terms of pure tone audiometry, speech audiometry, and tympanometry. Auditory brainstem response (ABR) and auditory middle latency response (AMLR) from both ears were tested. Absolute latencies and amplitudes of waves in ABR and AMLR were obtained and analyzed.Results: The absolute latencies of wave I and V significantly differed between musicians and non-musicians. They were shorter for musicians than for non-musicians. Significant differences were found in the interpeak latencies of wave III-V and I-V between musicians and non-musicians. They were also shorter in musicians than for non-musicians. In addition, there were only significant differences in the latency of Na in AMLR between musicians and non-musicians. It was shorter for a musician than for non-musician.Conclusion: ABR was more sensitive to the efficacy of the music training.

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O’Brien, Jennifer L., Dee A. Nikjeh et Jennifer J. Lister. « Interaction of Musicianship and Aging : A Comparison of Cortical Auditory Evoked Potentials ». Behavioural Neurology 2015 (2015) : 1–12. http://dx.doi.org/10.1155/2015/545917.

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Objective. The goal of this study was to begin to explore whether the beneficial auditory neural effects of early music training persist throughout life and influence age-related changes in neurophysiological processing of sound.Design. Cortical auditory evoked potentials (CAEPs) elicited by harmonic tone complexes were examined, including P1-N1-P2, mismatch negativity (MMN), and P3a.Study Sample. Data from older adult musicians (n=8) and nonmusicians (n=8) (ages 55–70 years) were compared to previous data from young adult musicians (n=40) and nonmusicians (n=20) (ages 18–33 years).Results. P1-N1-P2 amplitudes and latencies did not differ between older adult musicians and nonmusicians; however, MMN and P3a latencies for harmonic tone deviances were earlier for older musicians than older nonmusicians. Comparisons of P1-N1-P2, MMN, and P3a components between older and young adult musicians and nonmusicians suggest that P1 and P2 latencies are significantly affected by age, but not musicianship, while MMN and P3a appear to be more sensitive to effects of musicianship than aging.Conclusions. Findings support beneficial influences of musicianship on central auditory function and suggest a positive interaction between aging and musicianship on the auditory neural system.

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McLoughlin, Shane, Ian Tyndall et Antonina Pereira. « Piloting a brief relational operant training program : analyses of response latencies and intelligence test performance ». European Journal of Behavior Analysis 19, n^o 2 (3 juillet 2018) : 228–46. http://dx.doi.org/10.1080/15021149.2018.1507087.

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Šída, Pavel, Marie Koupilová, Sixtus Hynie et Věra Klenerová. « Effects of Two Types of Restraint Stress on the Learned Behaviour in Rats ». Acta Medica (Hradec Kralove, Czech Republic) 46, n^o 4 (2003) : 153–56. http://dx.doi.org/10.14712/18059694.2019.25.

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To study the effects of stress on cognitive functions, Wistar and Lewis rats were exposed to restraint (immobilization stressor) (IMO) or restraint combined with partial immersion into water (IMO+C). Learned discriminatory avoidance response in Y-maze, with foot-shock as an unconditioned stimulus, was used as a memory test. The latency to enter the correct arm and number of wrong entries were daily recorded during the training period (20 days) until the criterion was reached, which was set at 90 % avoidances (choosing the correct arm). After exposure of rats to one of the stressors for 60 min, the rats were returned to the home cage; the latency to enter the safe arm was recorded in 6 daily trials that started 1 h after application of stressor. Both stressors significantly prolonged the avoidance latencies for 2 or 3 days in Wistar and Lewis rats, respectively; then the latencies returned to the values obtained before the stress exposure. In Lewis rats, the latencies more increased after IMO+C than after IMO stressor, and the maximal increase in latencies was higher in Lewis rats than in Wistar rats. The latency did not reach the time limit for foot-shock delivery, and the number of correct choices remained unchanged in both strains. The results indicate that the used restraint stressors did not affect the long-term memory; rather a transient impairment of retrieval can be considered. Further, differences in response of Lewis and Wistar rats may be interpreted by different activity of hypothalamic-pituitary-adrenal axis activity in used strains.

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Dickstein, Ruth, Yael Heffes, Yocheved Laufer, Nir Abulaffio et Esther L. Shabtai. « Repetitive Practice of a Single Joint Movement for Enhancing Elbow Function in Hemiparetic Patients ». Perceptual and Motor Skills 85, n^o 3 (décembre 1997) : 771–85. http://dx.doi.org/10.2466/pms.1997.85.3.771.

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The primary goal of this study was to assess whether repetitive practice of flexion-extension movements of the affected elbow in hemiparetic patients enhances performance and to compare the effects of this practice mode to the effects of the physical therapy variable exercise program which is routinely applied during sessions. Subjects were 27 poststroke hemiparetic patients, residents of a rehabilitation institute, divided into an experimental ( n= 15) and a control group ( n = 12). The former were treated with 800 repeated elbow movements in a maximal predetermined amplitude of 80°, provided in 8 equal sessions every other day. The latter received 10 min. of conventional physical therapy for the paretic upper extremity at similar time intervals. Pre- and posttreatment assessments included the bilateral measurements of kinematic variables and activation latencies of the biceps and triceps brachi muscles as well as motor and functional tests. For all criterion variables, the findings pointed to comparable improvement in both groups. It was concluded that repetitive elbow movements had no unique training effect on the kinematics of movement and on activation latencies of the primary muscles controlling elbow function in hemiparetic patients. Further, transfer of the effects of training to execution of movements towards and from the mouth was also comparable in both groups, pointing again to there being no particular advantage in using repetitive movements as a training mode for enhancement of elbow function in hemiparetic patients.

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Rongzhu, L., W. Suhua, X. Guangwei, H. Fangan, C. Ziqiang, J. Fusheng et S. Kacew. « Neurobehavioral alterations in rats exposed to acrylonitrile in drinking water ». Human & ; Experimental Toxicology 26, n^o 3 (mars 2007) : 179–84. http://dx.doi.org/10.1177/0960327107070563.

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This study was carried out on rodents, to explore the neurobehavioral effects of acrylonitrile (AN) administered in drinking water. Thirty, male, Sprague-Dawley rats were randomly divided into three groups: two exposure groups (50 and 200 ppm AN), and one control group (tap water without AN). Three tests, including the open field test, rotarod test and spatial water maze, were applied to evaluate locomotor activities, motor co-ordination and learning and memory, respectively, prior to initiation of the treatment, and at Week 4, 8 and 12 postexposure. There were no consistent changes in the open field test, except for locomotion and grooming episodes. In the rotarod test, AN significantly decreased the latencies to fall in a dose and time-dependent manner. In the spatial water maze test, rats exposed to AN for 12 weeks had significantly more training times and longer escape latencies than control animals. These findings indicate that oral exposure to AN induces neurobehavioral alterations in rats.

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Covey, Thomas J., Janet L. Shucard, Ralph HB Benedict, Bianca Weinstock-Guttman et David W. Shucard. « Improved cognitive performance and event-related potential changes following working memory training in patients with multiple sclerosis ». Multiple Sclerosis Journal - Experimental, Translational and Clinical 4, n^o 1 (janvier 2018) : 205521731774762. http://dx.doi.org/10.1177/2055217317747626.

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Background Few studies of cognitive rehabilitation in multiple sclerosis (MS) have targeted working memory specifically. Objective We examined the effects of n-back working memory training on cognitive performance and brain function in patients with MS. Methods Patients with MS ( n = 12) and healthy controls (HC; n = 12) underwent 20 sessions of n-back working memory training. Before and after training (pre- and posttest) cognitive event-related potential (ERP) measures were obtained during a 3-back task. In addition, a battery of cognitive tests was administered. Results Following n-back training, both MS patients and HCs showed significant improvement on tests of working memory, processing speed, complex attention, and reasoning ability. MS and HCs also exhibited an enhancement of N2 ERP component amplitude, and earlier N2 and P3 latencies, following n-back training. Conclusions Targeted training of working memory with the n-back task may improve cognitive function in MS. Enhancement of N2 ERP component amplitude and shorter N2 and P3 latency following training in patients with MS is consistent with plasticity of neural processes that are involved in working memory.

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Fonseca, Maria Luiza A., et Angélica S. Vasconcellos. « Can Dogs’ Origins and Interactions with Humans Affect Their Accomplishments ? A Study on the Responses of Shelter and Companion Dogs during Vocal Cue Training ». Animals 11, n^o 5 (11 mai 2021) : 1360. http://dx.doi.org/10.3390/ani11051360.

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The inclusion of life history as a possible influential factor is pivotal in studies on behavior, welfare, and cognition. Shelter dogs have usually experienced a life involving poor social interactions with humans. Thus, we aimed to investigate the behavioral responses of shelter dogs (SDs) and companion dogs (CDs) during the training of two vocal cues (“sit”, “paw”), as well as the possible associations between their responses and the behaviors of trainers. We studied 15 SDs and 15 CDs in up to eight five-minute training sessions. Dogs’ and trainers’ behaviors were recorded and analyzed (through GLM, GLMM, correlation and Mann–Whitney tests). Shelter dogs responded to more cues per session, with shorter latencies and fewer repetitions of cues. Moreover, SDs spent more time wagging their tails. Dogs’ sex and trainers’ behaviors were also associated with differences in dogs’ responses. The use of a reproachful tone of voice was associated with a greater number of cues responded to, shorter latencies, and fewer repetitions of cues. However, this type voice/discourse was also linked to a greater exhibition of non-training behaviors (e.g., exploring the room or jumping on the trainer), and to dogs spending less time next to the trainer and wagging their tails. On the other hand, the use of a neutral tone of voice and laughter, besides being linked to performance, was also associated with longer durations of tail wagging. Furthermore, the duration of the trainers’ orientation to dogs was correlated with the orientation of the dogs to the trainers. Our data suggest that, even when having experienced social deprivation from humans, SDs’ capacities to learn vocal cues were preserved, possibly due to ontogenic homeostasis processes. Shelter dogs’ greater interest in the sessions may be also credited to their socially-deprived routine. Our outcomes also point to an association between friendly interactions during training and dog performance and excitement, which suggests that such interactions may have the potential to improve SD welfare.

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Ballesteros, Soledad, Jennifer Rieker, josé M. Reales, julia Mayas, María Pilar Jiménez, Antonio Prieto et Pilar Toril. « IS COMBINED TRAINING MORE EFFECTIVE THAN SINGLE-DOMAIN TRAINING : A RANDOMIZED CONTROLLED TRIAL WITH OLDER ADULTS ». Innovation in Aging 3, Supplement_1 (novembre 2019) : S721. http://dx.doi.org/10.1093/geroni/igz038.2644.

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Abstract Previous research suggests that both cognitive training and physical exercise help to maintain brain health and cognitive functions that decline with age. The main objectives of this four-arms RCT are (1) to investigate the synergetic effects of a group-based multidomain training program that combines cognitive video-game training with physical exercise, in comparison to those produced by cognitive training combined with physical control activity, physical training combined with cognitive control activity, or a combination of both control activities; (2) to investigate in a memory-based task switching task whether event Related Potential (ERP) latencies of the P2 component are shorter, and N2 and P3b components are enhanced after training; and (3) to find out whether possible enhancements persist after a 3-month period without training. One hundred and twenty participants will be randomly assigned to one of the four combinations of cognitive training and physical exercise. The cognitive component will be either video-game training (cognitive intervention, CI) or video games not specifically designed to train cognition (cognitive control, CC). The physical exercise component will either emphasize endurance, strength, and music-movement coordination (exercise intervention, EI) or stretching, toning and relaxation (exercise control, EC). This RCT will investigate the short and long-term effects of combined multi-domain training compared to cognitive training and physical training alone, on executive control and memory functions of healthy older adults, in comparison with the performance of an active control group. This trial is an ongoing project started in 2018. Trial registration: Clinicaltrials.gov ID: NCT03823183; https://register.clinicaltrials.gov/

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HORSWILL, MARK S., KAARIN J. ANSTEY, CHRISTOPHER G. HATHERLY et JOANNE M. WOOD. « The crash involvement of older drivers is associated with their hazard perception latencies ». Journal of the International Neuropsychological Society 16, n^o 5 (28 mai 2010) : 939–44. http://dx.doi.org/10.1017/s135561771000055x.

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AbstractHazard perception in driving is the one of the few driving-specific skills associated with crash involvement. However, this relationship has only been examined in studies where the majority of individuals were younger than 65. We present the first data revealing an association between hazard perception and self-reported crash involvement in drivers aged 65 and over. In a sample of 271 drivers, we found that individuals whose mean response time to traffic hazards was slower than 6.68 s [the receiver operating characteristic (ROC) curve derived pass mark for the test] were 2.32 times [95% confidence interval (CI), 1.46, 3.22) more likely to have been involved in a self-reported crash within the previous 5 years than those with faster response times. This likelihood ratio became 2.37 (95% CI, 1.49, 3.28) when driving exposure was controlled for. As a comparison, individuals who failed a test of useful field of view were 2.70 (95% CI, 1.44, 4.44) times more likely to crash than those who passed. The hazard perception test and the useful field of view measure accounted for separate variance in crash involvement. These findings indicate that hazard perception testing and training could be potentially useful for road safety interventions for this age group. (JINS, 2010, 16, 939–944.)

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Pinto, Maria, Francisco Javier Navas González, Camie Heleski et Amy McLean. « Judgement Bias in Miniature Donkeys : Conditioning Factors and Personality Links ». Animals 11, n^o 9 (19 septembre 2021) : 2737. http://dx.doi.org/10.3390/ani11092737.

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Expectation-related bias may configure individuals’ perception of their surrounding environment and of the elements present in it. This study aimed to determine the repercussions of environmental (weather elements) or subject-inherent factors (sex, age, or personality features) on judgment bias. A cognitive bias test was performed in eight Miniature jennies and four jacks. Test comprised habituation, training and testing phases during which subjects were trained on how to complete the test and scored based on their latency to approach an ambiguous stimulus. A questionnaire evaluating eleven personality features was parallelly completed by three caretakers, five operators and two care assistants to determine the links between personality features and judgment bias. Adjusted latencies did not significantly differ between sexes (Mann–Whitney test, p > 0.05). Although Miniature donkeys can discriminate positive/negative stimuli, inter-individual variability evidences were found. Such discrimination is evidenced by significant latency differences to approach positive/negative stimuli (33.7 ± 43.1 vs. 145.5 ± 53.1 s) (Mann–Whitney test, p < 0.05). Latencies significantly increased with patience, indicative of an expression of pessimism. Better understanding judgement bias mechanisms and implications may help optimize routine handling practices in the framework of animal welfare.

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Vicens, Paloma, M. Carmen Carrasco et Rosa Redolat. « Effects of Early Training and Nicotine Treatment on the Performance of Male NMRI Mice in the Water Maze ». Neural Plasticity 10, n^o 4 (2003) : 303–17. http://dx.doi.org/10.1155/np.2003.303.

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This research aimed to evaluate the effect of nicotine treatment and prior training on a spatial learning task in differently aged NMRI male mice. In a longitudinal study, mice were randomly assigned to one of 14 experimental groups receiving different combinations of chronically injected nicotine (0.35 mg/kg) administered for 10 days (5 days before and during 5 days acquisition of task) or control treatments and training in the water maze at different ages. The mice displayed shorter escape latencies when evaluated at 6 and 10 months than when tested in this task at 2 months for the first time, demonstrating that early training preserves performance in the water maze up to 8 months after the initial experience. Nicotine treatment did not significantly change performance in the water maze at any age tested. Early practice in a spatial reference memory task appears to have lasting consequences and can potentially contribute to preventing some age-related spatial learning deficits.

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Bugos, Jennifer A., Gavin M. Bidelman, Sylvain Moreno, Dawei Shen, Jing Lu et Claude Alain. « Music and Visual Art Training Increase Auditory-Evoked Theta Oscillations in Older Adults ». Brain Sciences 12, n^o 10 (27 septembre 2022) : 1300. http://dx.doi.org/10.3390/brainsci12101300.

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Music training was shown to induce changes in auditory processing in older adults. However, most findings stem from correlational studies and fewer examine long-term sustainable benefits. Moreover, research shows small and variable changes in auditory event-related potential (ERP) amplitudes and/or latencies in older adults. Conventional time domain analysis methods, however, are susceptible to latency jitter in evoked responses and may miss important information of brain processing. Here, we used time-frequency analyses to examine training-related changes in auditory-evoked oscillatory activity in healthy older adults (N = 50) assigned to a music training (n = 16), visual art training (n = 17), or a no-treatment control (n = 17) group. All three groups were presented with oddball auditory paradigms with synthesized piano tones or vowels during the acquisition of high-density EEG. Neurophysiological measures were collected at three-time points: pre-training, post-training, and at a three-month follow-up. Training programs were administered for 12-weeks. Increased theta power was found pre and post- training for the music (p = 0.010) and visual art group (p = 0.010) as compared to controls (p = 0.776) and maintained at the three-month follow-up. Results showed training-related plasticity on auditory processing in aging adults. Neuroplastic changes were maintained three months post-training, suggesting music and visual art programs yield lasting benefits that might facilitate encoding, retention, and memory retrieval.

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Buriti, Ana Karina Lima, et Daniela Gil. « Mild Traumatic Brain Injury : Long-Term Follow-Up of Central Auditory Processing After Auditory Training ». Journal of Audiology and Otology 26, n^o 1 (10 janvier 2022) : 22–30. http://dx.doi.org/10.7874/jao.2021.00360.

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Background and Objectives: Even a mild traumatic brain injury can impair the peripheral and central parts of the auditory system. The objective was to compare the performance of individuals with mild traumatic brain injury in behavioral and electrophysiological central auditory tests before and after formal auditory training, and to verify the stability of these measures over time. Subjects and Methods: Ten 16- to 64-year-old individuals diagnosed with mild traumatic brain injury underwent behavioral and electrophysiological assessment of the central auditory processing in three stages: before, right after, and six months after formal auditory training. Results: Statistically significant differences were observed for speech by white noise, synthetic sentence identification, sound localization, verbal sequential memory, and duration pattern tests in the assessment six months after formal auditory training. No statistically significant differences were observed between the P300 assessments, either with tone-burst or speech stimulus, in N2 and P3 latencies, and P3 amplitude. Conclusions: The results of the behavioral assessment of the central auditory processing improved, while the P300 remained stable with both stimuli, six months after completing formal auditory training. This demonstrates that auditory training has long-term benefits for people with mild traumatic brain injury.

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Marquez, Bicky A., Matthew J. Filipovich, Emma R. Howard, Viraj Bangari, Zhimu Guo, Hugh D. Morison, Thomas Ferreira De Lima, Alexander N. Tait, Paul R. Prucnal et Bhavin J. Shastri. « Silicon photonics for artificial intelligence applications ». Photoniques, n^o 104 (septembre 2020) : 40–44. http://dx.doi.org/10.1051/photon/202010440.

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Artificial intelligence enabled by neural networks has enabled applications in many fields (e.g. medicine, finance, autonomous vehicles). Software implementations of neural networks on conventional computers are limited in speed and energy efficiency. Neuromorphic engineering aims to build processors in which hardware mimic neurons and synapses in brain for distributed and parallel processing. Neuromorphic engineering enabled by silicon photonics can offer subnanosecond latencies, and can extend the domain of artificial intelligence applications to high-performance computing and ultrafast learning. We discuss current progress and challenges on these demonstrations to scale to practical systems for training and inference.

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Chen, Ji-Hong, Qian Zhang, Xin Liu, Zhixin Li, Cuizhen Zhang, Kongling Li, Jonathan Paul et al. « Noninvasive measurements to evaluate the effects of military training on the human autonomic nervous system ». Asian Biomedicine 8, n^o 4 (1 août 2014) : 453–61. http://dx.doi.org/10.5372/1905-7415.0804.314.

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AbstractBackground: Chinese university freshmen receive 4-weeks military training that involved moderate to intense physical exercise. Studies have demonstrated heterogeneous effects of exercise on the autonomic nervous system.Objective: To evaluate the effects of training on the autonomic nervous system noninvasively using electrogastrograms, heart rate variability (HRV), pulse rate, and the sympathetic skin response (SSR).Methods: Twenty freshmen received all assessments in the fasting state and after a standard meal: (1) one week before the training, (2) at the end of the second week of the training, and (3) one week after the training.Results: (1) The training had a significant effect on meal-induced gastric pacemaker activity. Before the training, a standard meal did not increase the dominant frequency of gastric slow waves, but the frequency increased during and after the training; (2) The preprandial high frequency (HF), low frequency (LF), and very low frequency (VLF) components of heart rate variability decreased significantly after the training. The ratio of the LF and HF (LF/HF) of the heart rate variability (HRV) did not significantly change after a meal or training condition. The basal pulse rate did not change. The latencies of the sympathetic skin response (SSR), as measured in the arm muscle, increased in response to the training.Conclusion: Military training affects meal-induced changes in gastric pacemaker activity, causes a marked reduction of the vagal tone to the heart with maintenance of the vagal-sympathetic balance, and its effects on SSR may reflect a reduction in sympathetic tone.

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Vollmer, Maike, Ralph E. Beitel, Christoph E. Schreiner et Patricia A. Leake. « Passive stimulation and behavioral training differentially transform temporal processing in the inferior colliculus and primary auditory cortex ». Journal of Neurophysiology 117, n^o 1 (1 janvier 2017) : 47–64. http://dx.doi.org/10.1152/jn.00392.2016.

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In profoundly deaf cats, behavioral training with intracochlear electric stimulation (ICES) can improve temporal processing in the primary auditory cortex (AI). To investigate whether similar effects are manifest in the auditory midbrain, ICES was initiated in neonatally deafened cats either during development after short durations of deafness (8 wk of age) or in adulthood after long durations of deafness (≥3.5 yr). All of these animals received behaviorally meaningless, “passive” ICES. Some animals also received behavioral training with ICES. Two long-deaf cats received no ICES prior to acute electrophysiological recording. After several months of passive ICES and behavioral training, animals were anesthetized, and neuronal responses to pulse trains of increasing rates were recorded in the central (ICC) and external (ICX) nuclei of the inferior colliculus. Neuronal temporal response patterns (repetition rate coding, minimum latencies, response precision) were compared with results from recordings made in the AI of the same animals (Beitel RE, Vollmer M, Raggio MW, Schreiner CE. J Neurophysiol 106: 944–959, 2011; Vollmer M, Beitel RE. J Neurophysiol 106: 2423–2436, 2011). Passive ICES in long-deaf cats remediated severely degraded temporal processing in the ICC and had no effects in the ICX. In contrast to observations in the AI, behaviorally relevant ICES had no effects on temporal processing in the ICC or ICX, with the single exception of shorter latencies in the ICC in short-deaf cats. The results suggest that independent of deafness duration passive stimulation and behavioral training differentially transform temporal processing in auditory midbrain and cortex, and primary auditory cortex emerges as a pivotal site for behaviorally driven neuronal temporal plasticity in the deaf cat. NEW & NOTEWORTHY Behaviorally relevant vs. passive electric stimulation of the auditory nerve differentially affects neuronal temporal processing in the central nucleus of the inferior colliculus (ICC) and the primary auditory cortex (AI) in profoundly short-deaf and long-deaf cats. Temporal plasticity in the ICC depends on a critical amount of electric stimulation, independent of its behavioral relevance. In contrast, the AI emerges as a pivotal site for behaviorally driven neuronal temporal plasticity in the deaf auditory system.

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Jóhannesson, Ómar I., Jay A. Edelman, Bjarki Dalsgaard Sigurþórsson et Árni Kristjánsson. « Effects of saccade training on express saccade proportions, saccade latencies, and peak velocities : an investigation of nasal/temporal differences ». Experimental Brain Research 236, n^o 5 (26 février 2018) : 1251–62. http://dx.doi.org/10.1007/s00221-018-5213-7.

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Coelho, Lucimara de Almeida, Marielli Fernanda Bezerra de Morais, Priscila de Araújo Lucas Rodrigues, Gabriela Coelho Pereira DeLuccia, Taina Maiza Bilinski Nardez, Adriana Bergamasco Vieira Futigami et Martha Takishima. « Home auditory training for children with impairment hearing due to cleft lip and palate ». Revista CEFAC 20, n^o 2 (avril 2018) : 154–65. http://dx.doi.org/10.1590/1982-0216201820220417.

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ABSTRACT Purpose: to verify the impact of home auditory training performed by parents for 30 days and the contribution to a better performance of the central auditory processing in children with auditory disorders resulting from cleft lip and palate. Methods: case studies were carried out with three children above seven years of age, presented with operated cleft lip and palate. Tests to assess peripheral hearing, behavioral and electrophysiological tests for central hearing assessment and Sustained Attention Auditory Ability ones, before and after the auditory training, were performed. Those responsible for the children answered a questionnaire which verified the auditory and attention behaviors altered by the impairment of the auditory processing. Results: improvement was seen in the majority of the behavioral tests of the auditory processing disorders, and in those which did not show variation after the training, the performance was maintained. Improvement was observed in the sustained attention as well as in the monitoring of all children of the study, post training. Improvement of the auditory behavior and also the decrease of latencies and the increase of amplitude of Na and Pa waves, after the training, were found. Conclusion: there was an enhancement in the performance of the central auditory processing of all children with operated cleft lip and palate, following auditory stimulation.

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Alkire, Michael T., Almira Vazdarjanova, Heather Dickinson-Anson, Nathan S. White et Larry Cahill. « Lesions of the Basolateral Amygdala Complex Block Propofol-induced Amnesia for Inhibitory Avoidance Learning in Rats ». Anesthesiology 95, n^o 3 (1 septembre 2001) : 708–15. http://dx.doi.org/10.1097/00000542-200109000-00025.

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Background As the unitary theory of anesthesia gives way to the "multiple sites, multiple mechanisms" concept, the sites involved in mediating the components of anesthesia must be identified. In the current study, we test the hypothesis that the basolateral amygdala complex (BLAC) is a brain site involved with mediating propofol-induced amnesia. Methods Male Sprague-Dawley rats were divided into two groups, sham-operated control animals and rats given bilateral excitotoxic N-methyl-D-aspartate lesions of the BLAC. For each group, animals were given intraperitoneal saline or propofol (25 mg/kg) 5 min before inhibitory avoidance learning. Rats were given a foot shock (0.4 mA) upon entering the dark side of a two-sided apparatus. Rats could escape additional shock by returning to and staying in the light side. Training ended after shock avoidance for greater than 60 s. Memory was tested at 24 h. Longer latencies to enter the dark side 24 h after training imply better memory. Results Sham-saline-treated animals had a robust memory latency (median latency [interquartile range] = 300 [163-567] s). Sham-propofo-treated animals exhibited a significant anterograde amnesia (latency = 63 [14-111] s) (P < 0.05 vs. sham-saline-treated animal). Both the saline-injected and propofol-injected animals with BLAC lesions showed robust memory (latency = 300 [264-485] and 323 [143480] s, respectively). These latencies did not differ from performance in the sham-saline-treated group and were significantly higher than the latency of the sham-propofol-treated group (both P < 0.05). Conclusions Discrete BLAC lesions blocked the amnestic effect of propofol. BLAC activity appears to be a requirement for propofol-induced amnesia. This finding suggests that the BLAC is a key brain site mediating anesthetic-induced amnesia.

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Leung, Joan H., Suzanne C. Purdy et Paul M. Corballis. « Improving Emotion Perception in Children with Autism Spectrum Disorder with Computer-Based Training and Hearing Amplification ». Brain Sciences 11, n^o 4 (8 avril 2021) : 469. http://dx.doi.org/10.3390/brainsci11040469.

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Individuals with Autism Spectrum Disorder (ASD) experience challenges with social communication, often involving emotional elements of language. This may stem from underlying auditory processing difficulties, especially when incoming speech is nuanced or complex. This study explored the effects of auditory training on social perception abilities of children with ASD. The training combined use of a remote-microphone hearing system and computerized emotion perception training. At baseline, children with ASD had poorer social communication scores and delayed mismatch negativity (MMN) compared to typically developing children. Behavioral results, measured pre- and post-intervention, revealed increased social perception scores in children with ASD to the extent that they outperformed their typically developing peers post-intervention. Electrophysiology results revealed changes in neural responses to emotional speech stimuli. Post-intervention, mismatch responses of children with ASD more closely resembled their neurotypical peers, with shorter MMN latencies, a significantly heightened P2 wave, and greater differentiation of emotional stimuli, consistent with their improved behavioral results. This study sets the foundation for further investigation into connections between auditory processing difficulties and social perception and communication for individuals with ASD, and provides a promising indication that combining amplified hearing and computer-based targeted social perception training using emotional speech stimuli may have neuro-rehabilitative benefits.

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Garner, Kelly G., Natasha Matthews, Roger W. Remington et Paul E. Dux. « Transferability of Training Benefits Differs across Neural Events : Evidence from ERPs ». Journal of Cognitive Neuroscience 27, n^o 10 (octobre 2015) : 2079–94. http://dx.doi.org/10.1162/jocn_a_00833.

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Humans can show striking capacity limitations in sensorimotor processing. Fortunately, these limitations can be attenuated with training. However, less fortunately, training benefits often remain limited to trained tasks. Recent behavioral observations suggest that the extent to which training transfers may depend on the specific stage of information processing that is being executed. Training benefits for a task that taps the consolidation of sensory information (sensory encoding) transfer to new stimulus–response mappings, whereas benefits for selecting an appropriate action (decision-making/response selection) remain specific to the trained mappings. Therefore, training may have dissociable influences on the neural events underlying subsequent sensorimotor processing stages. Here, we used EEG to investigate this possibility. In a pretraining baseline session, participants completed two four-alternative-choice response time tasks, presented both as a single task and as part of a dual task (with another task). The training group completed a further 3,000 training trials on one of the four-alternative-choice tasks. Hence, one task became trained, whereas the other remained untrained. At test, a negative-going component that is sensitive to sensory-encoding demands (N2) showed increased amplitudes and reduced latencies for trained and untrained mappings relative to a no-train control group. In contrast, the onset of the stimulus-locked lateralized readiness potential, a component that reflects the activation of motor plans, was reduced only for tasks that employed trained stimulus–response mappings, relative to untrained stimulus–response mappings and controls. Collectively, these results show that training benefits are dissociable for the brain events that reflect distinct sensorimotor processing stages.

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Budzynski, C. A., F. C. Dyer et V. P. Bingman. « Partial experience with the arc of the sun is sufficient for all-day sun compass orientation in homing pigeons, Columba livia ». Journal of Experimental Biology 203, n^o 15 (1 août 2000) : 2341–48. http://dx.doi.org/10.1242/jeb.203.15.2341.

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The ability of animals to learn to use the sun for orientation has been explored in numerous species. In birds, there is conflicting evidence about the experience needed for sun compass orientation to develop. The prevailing hypothesis is that birds need entire daytime exposure to the arc of the sun to use the sun as an orientation cue. However, there is also some evidence indicating that, even with limited exposure to the arc of the sun, birds, like insects, can use the sun to orient at any time of day. We re-examine this issue in a study of compass orientation in a cue-controlled arena. Two groups of young homing pigeons received different exposure to the sun. The control group experienced the sun throughout the day; the experimental group experienced only the apparent descent of the sun. After 8 weeks of sun exposure, we trained both groups in the afternoon to find food in a specific compass direction in an outdoor arena that provided a view of the sun but not landmarks. We then tested the pigeons in the morning for their ability to use the morning sun as an orientation cue. The control group and the experimental group, which was exposed to the morning sun for the first time, succeeded in orienting in the training direction during test 1. The orientation of the experimental group was no different from that of the control group, although the experimental first trial directional response latencies were greater than the control latencies. Subsequently, we continued training both groups in the afternoon and then tested the pigeons during the morning under complete cloud cover. Both groups displayed random directional responses under cloud cover, indicating that the observed orientation was based on the visibility of the sun. The data indicate that pigeons with limited exposure to the arc of the sun can, like insects, use the sun for orientation at any time of day.

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Zanesco, Anthony P., Brandon G. King, Chivon Powers, Rosanna De Meo, Kezia Wineberg, Katherine A. MacLean et Clifford D. Saron. « Modulation of Event-related Potentials of Visual Discrimination by Meditation Training and Sustained Attention ». Journal of Cognitive Neuroscience 31, n^o 8 (août 2019) : 1184–204. http://dx.doi.org/10.1162/jocn_a_01419.

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The ability to discriminate among goal-relevant stimuli tends to diminish when detections must be made continuously over time. Previously, we reported that intensive training in shamatha (focused-attention) meditation can improve perceptual discrimination of difficult-to-detect visual stimuli [MacLean, K. A., Ferrer, E., Aichele, S. R., Bridwell, D. A., Zanesco, A. P., Jacobs, T. L., et al. Intensive meditation training improves perceptual discrimination and sustained attention. Psychological Science, 21, 829–839, 2010]. Here we extend these findings to examine how discrimination difficulty and meditation training interact to modulate event-related potentials of attention and perceptual processing during vigilance. Training and wait-list participants completed a continuous performance task at the beginning, middle, and end of two 3-month meditation interventions. In the first intervention (Retreat 1), the continuous performance task target was adjusted across assessments to match training-related changes in participants' perceptual capacity. In the second intervention (Retreat 2), the target was held constant across training, irrespective of changes in discrimination capacity. No training effects were observed in Retreat 1, whereas Retreat 2 was associated with changes in the onset of early sensory signals and an attenuation of within-task decrements at early latencies. In addition, changes at later stimulus processing stages were directly correlated with improvements in perceptual threshold across the second intervention. Overall, these findings demonstrate that improvements in perceptual discrimination can modulate electrophysiological markers of perceptual processing and attentional control during sustained attention, but likely only under conditions where an individual's discrimination capacity is allowed to exceed the demand imposed by the difficulty of a visual target. These results contribute to basic understanding of the dependence of perceptual processing and attentional control to contextual demands and their susceptibility to directed mental training.

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Antoniaci Mariane Richetto da Silva, Andrade Adriana Neves de, Suriano Italo Capraro, Avila Clara Regina Brandão de et Gil Daniela. « Electrophysiological and behavioral evaluation of auditory processing before and after speech therapy intervention in children after traumatic brain injury : Case reports ». World Journal of Biology Pharmacy and Health Sciences 5, n^o 3 (30 mars 2021) : 064–74. http://dx.doi.org/10.30574/wjbphs.2021.5.3.0025.

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Objectives: to verify the effects of a speech therapy intervention program in children after moderate and severe traumatic brain injury using electrophysiological and behavioral assessment of central auditory processing. Method: Five children aged 9 to 11 years old who suffered closed brain trauma of moderate or severe degree for at least 6 months, right-handed, literate before the injury, diagnosed with Central Auditory Processing and Reading and Writing Disorders. Ten speech therapy intervention sessions were held, covering the area of language and auditory training activities. Children were submitted to electrophysiological evaluation with Long Latency Auditory Evoked Potential and behavioral assessment of central auditory processing, pre and post intervention. Results: Statistically significant, after speech therapy intervention, in the LLAEP with tone burst, there was an improvement in the latencies of the N2 component in both ears and P3 in the right ear. CAPD improves the memory test for verbal sounds in sequence and the speech test with white noise in the right ear. Conclusion: After the speech therapy intervention program in individuals with TBI it was observed: reduction of the latency of the N1 component in the left ear, in the LLAEP with tone burst; reduction of the latencies of the components N1, P2 and N2 in the right and left ears, and for the latency of the P3 only in the right ear, in the LLAEP with complex stimuli and performance improvement in the behavioral tests of central auditory memory processing for verbal sounds in sequence and speech with white noise.

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Brown, Valerie, Dale Huey et John M. Findlay. « Face Detection in Peripheral Vision : Do Faces Pop Out ? » Perception 26, n^o 12 (décembre 1997) : 1555–70. http://dx.doi.org/10.1068/p261555.

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We examined whether faces can produce a ‘pop-out’ effect in visual search tasks. In the first experiment, subjects' eye movements and search latencies were measured while they viewed a display containing a target face amidst distractors. Targets were upright or inverted faces presented with seven others of the opposite polarity as an ‘around-the-clock’ display. Face images were either photographic or ‘feature only’, with the outline removed. Naive subjects were poor at locating an upright face from an array of inverted faces, but performance improved with practice. In the second experiment, we investigated systematically how training improved performance. Prior to testing, subjects were practised on locating either upright or inverted faces. All subjects benefited from training. Subjects practised on upright faces were faster and more accurate at locating upright target faces than inverted. Subjects practised on inverted faces showed no difference between upright and inverted targets. In the third experiment, faces with ‘jumbled’ features were used as distractors, and this resulted in the same pattern of findings. We conclude that there is no direct rapid ‘pop-out’ effect for faces. However, the findings demonstrate that, in peripheral vision, upright faces show a processing advantage over inverted faces.

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Bento-Torres, Natáli Valim Oliver, João Bento-Torres, Alessandra Mendonça Tomás, Luís Gustavo Torres de Souza, Jéssica Oliveira de Freitas, Jefferson Anderson dos Santos Pantoja et Cristovam Wanderley Picanço-Diniz. « WATER-BASED EXERCISE AND RESISTANCE TRAINING IMPROVE COGNITION IN OLDER ADULTS ». Revista Brasileira de Medicina do Esporte 25, n^o 1 (février 2019) : 71–75. http://dx.doi.org/10.1590/1517-869220192501190627.

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ABSTRACT Introduction: Physical exercise has been associated with maintenance of physical abilities and the reduction of age-related cognitive decline, and is considered both a low-cost primary prevention strategy and a non-pharmacological treatment of cognitive dysfunction in older people. However, the contribution of each type of physical exercise to the cognitive health of the elderly population has not yet been fully investigated. Objective: This study investigated the possible influences of water-based and resistance training exercises on the cognitive performance of healthy older adults in automated tests, and investigated which test(s) would be the most effective indicator of differences in aging cognitive performance. Methods: Three groups of community-dwelling healthy older adults: water-based exercise group, resistance training group and sedentary group, were assessed using an automated set of neuropsychological tests (CANTAB) and tests to assess functional exercise capacity. Results were compared by one-way analysis of variance (ANOVA) and Pearson linear correlation. Results: The water-based exercise group had the best functional exercise capacity scores and the best performance in the reaction time evaluation (response and movement latencies). The resistance training group had less movement latency than the sedentary group. Functional mobility was positively correlated with response and movement latency. Conclusions: Taken together our findings show that physical exercise contributes to the preservation of cognitive function in healthy older adults and that water-based exercise has better results than resistance training in terms of reaction time. Moreover, the changes related to reaction time function were detected before the changes in working memory functions, sustained attention and learning in the sedentary participants, suggesting that this variable could be an early sensitive indicator of subtle cognitive changes associated with aging. Level of Evidence II; Retrospective study.

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Semba, Kazunori, Naoto Adachi et Tatsuru Arai. « Facilitation of Serotonergic Activity and Amnesia in Rats Caused by Intravenous Anesthetics ». Anesthesiology 102, n^o 3 (1 mars 2005) : 616–23. http://dx.doi.org/10.1097/00000542-200503000-00021.

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Background Midazolam and propofol often provoke retrograde amnesia after recovery from anesthesia in humans. Because an increase in central serotonergic activity impairs learning and memory, the authors examined the relation between changes in the serotonergic activity caused by intravenous anesthetics and memory. Methods Changes in extracellular concentrations of monoamines and their metabolites were investigated in rat striatum by a microdialysis procedure, and the effects of intraperitoneal injections of midazolam (5 mg/kg), propofol (60 mg/kg), and pentobarbital (15 mg/kg) were then examined. To evaluate the behavioral alteration with these agents, the authors used a step-through passive avoidance test. Results Midazolam and propofol slightly increased the extracellular concentration of 5-hydroxytryptamine in the striatum, although pentobarbital did not produce any changes. Midazolam and propofol increased the extracellular concentration of 5-hydroxyindoleacetic acid, a metabolite of 5-hydroxytryptamine, with the peak values each 138% and 138% of that in saline-injected animals, respectively. However, pentobarbital decreased the 5-hydroxyindoleacetic acid concentration to 61% of that in the saline group. Administration of midazolam or propofol immediately after the completing the passive avoidance learning reduced step-through latencies after 24 h, although pentobarbital-injected animals maintained a consistent performance. The effects of midazolam and propofol on step-through latencies were completely antagonized by intracerebroventricular administration of spiroxatrine (5 microg), a 5-hydroxytryptamine 1A antagonist, 30 min before training. Conclusions Midazolam and propofol increased central serotonergic activity and provoked retrograde amnesia. Because amnesia was completely diminished by a 5-hydroxytryptamine antagonist, facilitation of the serotonergic system may be involved in retrograde amnesia caused by these agents.

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Failing, Michel, Tom Nissens, Daniel Pearson, Mike Le Pelley et Jan Theeuwes. « Oculomotor capture by stimuli that signal the availability of reward ». Journal of Neurophysiology 114, n^o 4 (octobre 2015) : 2316–27. http://dx.doi.org/10.1152/jn.00441.2015.

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It is well known that eye movement patterns are influenced by both goal- and salience-driven factors. Recent studies, however, have demonstrated that objects that are nonsalient and task irrelevant can still capture our eyes if moving our eyes to those objects has previously produced reward. Here we demonstrate that training such an association between eye movements to an object and delivery of reward is not needed. Instead, an object that merely signals the availability of reward captures the eyes even when it is physically nonsalient and never relevant for the task. Furthermore, we show that oculomotor capture by reward is more reliably observed in saccades with short latencies. We conclude that a stimulus signaling high reward has the ability to capture the eyes independently of bottom-up physical salience or top-down task relevance and that the effect of reward affects early selection processes.

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HAHN, CHRISTIAN G. K., HENRIK SAALBACH et ROLAND H. GRABNER. « Language-dependent knowledge acquisition : investigating bilingual arithmetic learning ». Bilingualism : Language and Cognition 22, n^o 1 (5 octobre 2017) : 47–57. http://dx.doi.org/10.1017/s1366728917000530.

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Previous studies revealed language-switching costs (LSC) in bilingual learning settings, consisting of performance decreases when problems are solved in a language different from that of instruction. Strong costs have been found for arithmetic fact knowledge. The aim of the present study was to investigate whether LSC in arithmetic also emerge in an auditory learning task and in pure fact learning. Furthermore, we tested whether LSC are influenced by the direction of language-switching. Thirty-three university students learned arithmetic facts of three different operations (i.e., multiplication, subtraction, artificial facts) over a period of four days. The training was either in German or English. On day five, participants solved problems in both languages. Results revealed LSC in response latencies for all three types of problems, independent of the direction of language-switching. These findings suggest that LSC are modality-unspecific and occur independent of the type of arithmetic fact knowledge.

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Ma, Ada W. W., Hsing-Kuo Wang, Duan-Rung Chen, Ya-Mei Chen, Yvonne T. C. Chak, Joan W. Y. Chan, Timothy T. T. Yam, Yoyo T. Y. Cheng, Balasankar Ganesan et Shirley S. M. Fong. « Chinese Martial Art Training Failed to Improve Balance or Inhibit Falls in Older Adults ». Perceptual and Motor Skills 126, n^o 3 (25 février 2019) : 389–409. http://dx.doi.org/10.1177/0031512518824945.

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This randomized controlled trial explored the effects of a Ving Tsun (VT) Chinese martial art training program on reactive standing balance performance, postural muscle reflex contraction latency, leg muscle performance, balance confidence and falls in community-dwelling older adults. We randomly assigned 33 healthy older adults to either a VT group (mean age = 67.5 years) or a control group (mean age = 72.1 years). The VT group received two 1-hour VT training sessions per week for three months (24 sessions). Primary outcome measures collected before and after the intervention period were electromyographic muscle activation onset latencies of the hamstring and gastrocnemius and the center of pressure path, length and movement velocity in standing (reactive balance performance). Secondary outcome measures included isometric peak force and time to isometric peak force of the knee extensors and flexors, the Activities-Specific Balance Confidence Scale score, and fall history. Results revealed that the mean gastrocnemius muscle activation onset latency was significantly longer (22.53 ms) in the VT group after the intervention. The peak force of the knee flexors significantly increased (by 1.58 kg) in the control group over time but not in the VT group. The time to reach peak force in the knee flexors was significantly longer (by 0.51 s) in the control group (but not the VT group) at posttest compared with the pretest value. No other significant group, time, or group-by-time interaction effects were noted. We discussed possible reasons for the failure of three months of martial art training to benefit fall risks among these older adults.

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Vollmer, Maike, et Ralph E. Beitel. « Behavioral training restores temporal processing in auditory cortex of long-deaf cats ». Journal of Neurophysiology 106, n^o 5 (novembre 2011) : 2423–36. http://dx.doi.org/10.1152/jn.00565.2011.

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Temporal auditory processing is poor in prelingually hearing-impaired patients fitted with cochlear prostheses as adults. In an animal model of prelingual long-term deafness, we investigated the effects of behavioral training on temporal processing in the adult primary auditory cortex (AI). Neuronal responses to pulse trains of increasing frequencies were recorded in three groups of neonatally deafened cats that received a cochlear prosthesis after >3 yr of deafness: 1) acutely implanted animals that received no electric stimulation before study, 2) animals that received chronic-passive stimulation for several weeks to months before study, and 3) animals that received chronic-passive stimulation and additional behavioral training (signal detection). A fourth group of normal adult cats that was deafened acutely and implanted served as controls. The neuronal temporal response parameters of interest included the stimulus rate that evoked the maximum number of phase-locked spikes [best repetition rate (BRR)], the stimulus rate that produced 50% of the spike count at BRR (cutoff rate), the peak-response latency, and the first spike latency and timing-jitter. All long-deaf animals demonstrated a severe reduction in spiral ganglion cell density (mean, <6% of normal). Long-term deafness resulted in a significantly reduced temporal following capacity and spike-timing precision of cortical neurons in all parameters tested. Neurons in deaf animals that received only chronic-passive stimulation showed a gain in BRR but otherwise were similar to deaf cats that received no stimulation. In contrast, training with behaviorally relevant stimulation significantly enhanced all temporal processing parameters to normal levels with the exception of minimum latencies. These results demonstrate the high efficacy of learning-based remodeling of fundamental timing properties in cortical processing even in the adult, long-deaf auditory system, suggesting rehabilitative strategies for patients with long-term hearing loss.

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Hung, Ching-Hsia, Po-Ching Huang, Jann-Inn Tzeng, Jhi-Joung Wang et Yu-Wen Chen. « Therapeutic Ultrasound and Treadmill Training Suppress Peripheral Nerve Injury–Induced Pain in Rats ». Physical Therapy 96, n^o 10 (1 octobre 2016) : 1545–53. http://dx.doi.org/10.2522/ptj.20140379.

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AbstractBackgroundAlthough evidence suggests that therapeutic ultrasound (TU) in combination with treadmill training (TT) suppresses nerve injury–associated pain, the molecular mechanisms for this action are not clear.ObjectiveThe purpose of this research was to study the possible beneficial effects of TU and TT, alone and in combination, on 2 clinical indicators of neuropathic pain and correlate these findings with changes in inflammatory mediators within the spinal cord. Our experimental model used the well-known chronic constriction injury (CCI) of the rat sciatic nerve.DesignThis was an experimental study.MethodsEach group contained 10 rats. Group 1 underwent only the CCI procedure. Group 2 underwent a sham operation where the sciatic nerve was exposed but not ligated. Group 3 had the sham operation followed by both TT and TU. Groups 4, 5, and 6 underwent the CCI procedure followed by TT alone, TU alone, and both the TT and TU interventions, respectively. Heat and mechanical sensitivity, interleukin-6 (IL-6), interleukin-10 (IL-10), and ionized calcium binding adaptor molecule 1 (Iba1) were evaluated.ResultsCompared with group 1 animals, TT or TU, or both, produced smaller decreases in mechanical withdrawal threshold and heat withdrawal latencies. The combination of TT and TU was more effective than either treatment alone. In addition, rats that received these treatments did not express the upregulation of IL-6 and Iba1 in their spinal cords on postoperative days 14 and 28, as was found in the group 1 animals.LimitationsThese experimental findings may not be generalizable to humans.ConclusionsThe combination of TU and TT reduces neuropathic pain more than either modality alone. This beneficial effect appears related to downregulation of proinflammatory IL-6 and Iba1, while upregulating the anti-inflammatory IL-10.

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Lin, Chiao-I., Mina Khajooei, Tilman Engel, Alexandra Nair, Mika Heikkila, Hannes Kaplick et Frank Mayer. « The effect of chronic ankle instability on muscle activations in lower extremities ». PLOS ONE 16, n^o 2 (22 février 2021) : e0247581. http://dx.doi.org/10.1371/journal.pone.0247581.

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Background/Purpose Muscular reflex responses of the lower extremities to sudden gait disturbances are related to postural stability and injury risk. Chronic ankle instability (CAI) has shown to affect activities related to the distal leg muscles while walking. Its effects on proximal muscle activities of the leg, both for the injured- (IN) and uninjured-side (NON), remain unclear. Therefore, the aim was to compare the difference of the motor control strategy in ipsilateral and contralateral proximal joints while unperturbed walking and perturbed walking between individuals with CAI and matched controls. Materials and methods In a cross-sectional study, 13 participants with unilateral CAI and 13 controls (CON) walked on a split-belt treadmill with and without random left- and right-sided perturbations. EMG amplitudes of muscles at lower extremities were analyzed 200 ms after perturbations, 200 ms before, and 100 ms after (Post100) heel contact while walking. Onset latencies were analyzed at heel contacts and after perturbations. Statistical significance was set at alpha≤0.05 and 95% confidence intervals were applied to determine group differences. Cohen’s d effect sizes were calculated to evaluate the extent of differences. Results Participants with CAI showed increased EMG amplitudes for NON-rectus abdominus at Post100 and shorter latencies for IN-gluteus maximus after heel contact compared to CON (p<0.05). Overall, leg muscles (rectus femoris, biceps femoris, and gluteus medius) activated earlier and less bilaterally (d = 0.30–0.88) and trunk muscles (bilateral rectus abdominus and NON-erector spinae) activated earlier and more for the CAI group than CON group (d = 0.33–1.09). Conclusion Unilateral CAI alters the pattern of the motor control strategy around proximal joints bilaterally. Neuromuscular training for the muscles, which alters motor control strategy because of CAI, could be taken into consideration when planning rehabilitation for CAI.

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Wang, Danping, Gael Mahe, Junying Fang, Julien Piscione, Serge Couvet, Didier Retiere, Sébastien Laporte et Pierre-Paul Vidal. « Inconsistent anticipatory postural adjustments (APAs) in rugby players : a source of injuries ? » BMJ Open Sport & ; Exercise Medicine 4, n^o 1 (juin 2018) : e000303. http://dx.doi.org/10.1136/bmjsem-2017-000303.

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BackgroundWe are developing since 2010 with Thales and theFédération Française de Rugby(FFR) M-Rex, a new kind of rugby scrum simulator. The study questioned whether it could improve safety and protect players from injury by using it as a tool for training/coaching the packs.AimTo explore the anticipatory postural adjustments (APAs) during the engagement of the ruck, because these predictive neck and back muscles contractions protect the spinal cord at the time of impacts, which is crucial to prevent injuries.MethodsWe quantified the kinematics and the EMG activities in high-level front row players during their initial engagement, when scrummaging with M-Rex. All studies were performed with one player interacting with the robot, at first, and then with the three players acting together.ResultsFor most of the tested high-level players, the APA latencies were highly variable from trial to trial even though the engagement resulted in similar impacts. At time, the onset of the electromyography activity in the neck and back muscles showed latencies inferior to 50 ms or even close to zero prior to the impact , which rendered muscle contractions inefficient as APAs. We were also unable to identify clear muscular synergies underlying the APAs because of their great variability on a trial-to-trial basis. Finally, the APAs were not related to the amplitude of the ensuing impact and were asymmetric in most trials. All these characteristics held true, whether the player was playing alone or with two other frontline players.ConclusionOur result suggest that APAs should be systematically tested in high-level rugby players as well as in any high-level sport men at risk of neck and back injuries. Because APAs can be efficiently trained, our study paves the way to design individual position-specific injury prevention programme.

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Bosse, Stefan, Armin Lechleiter et Dirk Lehmhus. « Data Evaluation in Smart Sensor Networks Using Inverse Methods and Artificial Intelligence (AI) : Towards Real-Time Capability and Enhanced Flexibility ». Advances in Science and Technology 101 (octobre 2016) : 55–61. http://dx.doi.org/10.4028/www.scientific.net/ast.101.55.

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Data evaluation is crucial for gaining information from sensor networks. Main challenges include processing speed and adaptivity to system change, both prerequisites for SHM-based weight reduction via relaxed safety factors. Our study looks at soft real time solutions providing feedback within defined but flexible, application-controlled intervals. These can rely on minimizing computation/communication latencies e.g. by parallel computation. Strategies towards this aim can be model-based, including inverse FEM, or model-free, including machine learning, which in practice bases training on a defined system state, too, hence also facing challenges at state changes. We thus introduce hybrid data evaluation combining multi-agent based systems (MAS) with inverse FEM, mainly relying on matrix operations that can be partially distributed: The MAS perform sensor data acquisition, aggregation, pre-computation, and finally application (the LM/SHM itself and higher information processing and visualization layers, i.e., WEB interfaces). System capabilities are evaluated against a virtual test case, demonstrating enhanced stability and reliability. Besides, we analyze system performance under conditions of in-service change and discuss system layouts suited to improve coverage of this issue.

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Liu, Huanhuan, Susan Dunlap, Lijuan Liang et Baoguo Chen. « The effect of inhibitory control and its training on L1 and a new learned language switching ». International Journal of Bilingualism 22, n^o 6 (1 février 2017) : 653–74. http://dx.doi.org/10.1177/1367006916688335.

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Aims: This study aimed to investigate how individuals’ inhibitory control (IC) ability affects language switching in the initial period of language learning. Design: Using a pretest/posttest design and event-related potential (ERP) methodology, we investigated the effect of IC on Chinese–English bilinguals during their language switching between Chinese (L1) and Korean (a language new to the participants, Lnew). All participants were required to name pictures (picture-naming task) in their L1 and Lnew in the pretest and posttest. Low-IC participants received an IC task training between the pretest and the posttest, while the high-IC group did not. Data and analysis: Analyses of both response latencies and ERP data were conducted by repeated-measures ANOVA. Findings: Results showed that the high-IC group exhibited symmetrical switch costs in both the pretest and the posttest. Besides, a more obvious late positive component (LPC) was observed when the high-IC participants switched from L1 to Lnew than the other way around, indicating their ability to inhibit cross-language interference. In contrast, the low-IC group exhibited asymmetrical switch costs, and no amplitude difference when switching between Lnew and L1 in the pretest. However, in the posttest, the switch costs pattern and the LPC results of the low-IC group became similar to those of the high-IC group. Innovation: The present study was a first attempt to provide electrophysiological evidence that IC ability plays an important role during L1–Lnew switching. Significance: These findings support the hypothesis that individuals’ IC ability plays a role of suppressing the non-target lexical access during language switching in the initial period of second language learning. The results also indicate that the relevant training in IC ability could contribute to the improvement of the language-switching efficiency in the initial period of language learning.

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Blake, David T., Fabrizio Strata, Richard Kempter et Michael M. Merzenich. « Experience-Dependent Plasticity in S1 Caused by Noncoincident Inputs ». Journal of Neurophysiology 94, n^o 3 (septembre 2005) : 2239–50. http://dx.doi.org/10.1152/jn.00172.2005.

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Prior work has shown that coincident inputs became corepresented in somatic sensory cortex. In this study, the hypothesis that the corepresentation of digits required synchronous inputs was tested, and the daily development of two-digit receptive fields was observed with cortical implants. Two adult primates detected temporal differences in tap pairs delivered to two adjacent digits. With stimulus onset asynchronies of ≥100 ms, representations changed to include two-digit receptive fields across the first 4 wk of training. In addition, receptive fields at sites responsive to the taps enlarged more than twofold, and receptive fields at sites not responsive to the taps had no significant areal change. Further training did not increase the expression of two-digit receptive fields. Cortical responses to the taps were not dependent on the interval length. Stimuli preceding a hit, miss, false positives, and true negatives differed in the ongoing cortical rate from 50 to 100 ms after the stimulus but did not differ in the initial, principal, response to the taps. Response latencies to the emergent responses averaged 4.3 ms longer than old responses, which occurs if plasticity is cortical in origin. New response correlations developed in parallel with the new receptive fields. These data show corepresentation can be caused by presentation of stimuli across a longer time window than predicted by spike-timing–dependent plasticity and suggest that increased cortical excitability accompanies new task learning.

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Hauer, Daniela, Patrizia Ratano, Maria Morena, Sergio Scaccianoce, Isabel Briegel, Maura Palmery, Vincenzo Cuomo, Benno Roozendaal, Gustav Schelling et Patrizia Campolongo. « Propofol Enhances Memory Formation via an Interaction with the Endocannabinoid System ». Anesthesiology 114, n^o 6 (1 juin 2011) : 1380–88. http://dx.doi.org/10.1097/aln.0b013e31821c120e.

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Background Propofol is associated with postoperative mood alterations and induces a higher incidence of dreaming compared with other general anesthetics. These effects might be mediated by propofol's inhibitory action on fatty acid amide hydrolase, the enzyme that degrades the endocannabinoid anandamide. Because propofol is also associated with a higher incidence of traumatic memories from perioperative awareness and intensive care unit treatment and the endocannabinoid system is involved in regulating memory consolidation of emotional experiences, the authors investigated whether propofol, at anesthetic doses, modulates memory consolidation via an activation of the endocannabinoid system. Methods Male Sprague-Dawley rats were trained on an inhibitory avoidance task in which they received an inescapable foot shock upon entering the dark compartment of the apparatus. Drugs were administered intraperitoneally immediately or 30, 90, or 180 min after training. On the retention test 48 h later, the latency to reenter the dark compartment was recorded and taken as a measure of memory retention. Results The anesthetic doses of propofol administered after training significantly increased latencies of 48-h inhibitory avoidance performance (483.4 ± 181.3, 432.89 ± 214.06, 300 and 350 mg/kg, respectively; mean ± SD) compared with the corresponding vehicle group (325.33 ± 221.22, mean ± SD), which is indicative of stronger memory consolidation in propofol treated rats. Administration of a nonimpairing dose of the cannabinoid receptor antagonist rimonabant blocked the memory enhancement induced by propofol (123.39 ± 133.10, mean ± SD). Delayed administration of propofol 90 and 180 min after training or immediate posttraining administration of the benzodiazepine midazolam or the barbiturate pentobarbital did not significantly alter retention. Conclusions These findings indicate that propofol, in contrast to other commonly used sedatives, enhances emotional memory consolidation when administered immediately after a stressful event by enhancing endocannabinoid signaling.

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Jaquerod, Manon E., Sarah K. Mesrobian, Alessandro E. P. Villa, Michel Bader et Alessandra Lintas. « Early Attentional Modulation by Working Memory Training in Young Adult ADHD Patients during a Risky Decision-Making Task ». Brain Sciences 10, n^o 1 (9 janvier 2020) : 38. http://dx.doi.org/10.3390/brainsci10010038.

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Background: Working memory (WM) deficits and impaired decision making are among the characteristic symptoms of patients affected by attention deficit/hyperactivity disorder (ADHD). The inattention associated with the disorder is likely to be due to functional deficits of the neural networks inhibiting irrelevant sensory input. In the presence of unnecessary information, a good decisional process is impaired and ADHD patients tend to take risky decisions. This study is aimed to test the hypothesis that the level of difficulty of a WM training (WMT) is affecting the top-down modulation of the attentional processes in a probabilistic gambling task. Methods: Event-related potentials (ERP) triggered by the choice of the amount wagered in the gambling task were recorded, before and after WMT with a the dual n-back task, in young ADHD adults and matched controls. For each group of participants, randomly assigned individuals were requested to perform WMT with a fixed baseline level of difficulty. The remaining participants were trained with a performance-dependent adaptive n-level of difficulty. Results: We compared the ERP recordings before and after 20 days of WMT in each subgroup. The analysis was focused on the time windows with at least three recording sites showing differences before and after training, after Bonferroni correction ( p < 0.05 ). In ADHD, the P1 wave component was selectively affected at frontal sites and its shape was recovered close to controls’ only after adaptive training. In controls, the strongest contrast was observed at parietal level with a left hemispheric dominance at latencies near 900 ms, more after baseline than after adaptive training. Conclusion: Partial restoration of early selective attentional processes in ADHD patients might occur after WMT with a high cognitive load. Modified frontal sites’ activities might constitute a neural marker of this effect in a gambling task. In controls, conversely, an increase in late parietal negativity might rather be a marker of an increase in transfer effects to fluid intelligence.

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Hopper, Lydia M., Matthias Allritz, Crystal L. Egelkamp, Sarah M. Huskisson, Sarah L. Jacobson, Jesse G. Leinwand et Stephen R. Ross. « A Comparative Perspective on Three Primate Species’ Responses to a Pictorial Emotional Stroop Task ». Animals 11, n^o 3 (24 février 2021) : 588. http://dx.doi.org/10.3390/ani11030588.

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The Stroop effect describes interference in cognitive processing due to competing cognitive demands. Presenting emotionally laden stimuli creates similar Stroop-like effects that result from participants’ attention being drawn to distractor stimuli. Here, we adapted the methods of a pictorial Stroop study for use with chimpanzees (N = 6), gorillas (N = 7), and Japanese macaques (N = 6). We tested all subjects via touchscreens following the same protocol. Ten of the 19 subjects passed pre-test training. Subjects who reached criterion were then tested on a standard color-interference Stroop test, which revealed differential accuracy in the primates’ responses across conditions. Next, to test for an emotional Stroop effect, we presented subjects with photographs that were either positively valenced (a preferred food) or negatively valenced (snakes). In the emotional Stroop task, as predicted, the primates were less accurate in trials which presented emotionally laden stimuli as compared to control trials, but there were differences in the apes’ and monkeys’ response patterns. Furthermore, for both Stroop tests, while we found that subjects’ accuracy rates were reduced by test stimuli, in contrast to previous research, we found no difference across trial types in the subjects’ response latencies across conditions.

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Ku, Bon Woong, Catherine D. Schuman, Md Musabbir Adnan, Tiffany M. Mintz, Raphael Pooser, Kathleen E. Hamilton, Garrett S. Rose et Sung Kyu Lim. « Unsupervised Digit Recognition Using Cosine Similarity In A Neuromemristive Competitive Learning System ». ACM Journal on Emerging Technologies in Computing Systems 18, n^o 2 (30 avril 2022) : 1–20. http://dx.doi.org/10.1145/3473036.

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This work addresses how to naturally adopt the l 2 -norm cosine similarity in the neuromemristive system and studies the unsupervised learning performance on handwritten digit image recognition. Proposed architecture is a two-layer fully connected neural network with a hard winner-take-all (WTA) learning module. For input layer, we propose single-spike temporal code that transforms input stimuli into the set of single spikes with different latencies and voltage levels. For a synapse model, we employ a compound memristor where stochastically switching binary-state memristors connected in parallel, which offers a reliable and scalable multi-state solution for synaptic weight storage. Hardware-friendly synaptic adaptation mechanism is proposed to realize spike-timing-dependent plasticity learning. Input spikes are sent out through those memristive synapses to each and every integrate-and-fire neuron in the fully connected output layer, where the hard WTA network motif introduces the competition based on cosine similarity for the given input stimuli. Finally, we present 92.64% accuracy performance on unsupervised digit recognition with only single-epoch MNIST dataset training via high-level simulations, including extensive analysis on the impact of system parameters.

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Kurylo, Daniel D., Ram L. Pandey Vimal et Peter H. Hartline. « Effects of Multiple Stimuli on Ocular Orientation by Cats ». Journal of Cognitive Neuroscience 4, n^o 2 (avril 1992) : 165–74. http://dx.doi.org/10.1162/jocn.1992.4.2.165.

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We investigated the characteristics of saccades made by cats in response to single and double stimuli. Stimuli were either visual, auditory, or bimodal. We initially trained cats to look toward the location of briefly presented single visual or single auditory targets that were extinguished before the initiation of eye movements. Following training, we monitored eye movements during and after the presentation of double targets, either two visual, two auditory, or bimodal, that were at disparate spatial locations. Cats made saccadic eye movements to positions that ranged between the location of the two targets. If the eye position at the start of a saccade was near the mid point of the targets, cats were less likely to initiate a saccade, and saccadic latencies were longer, compared to when starting eye position was at a distance from this location. These behavioral results are consistent with the hypothesis that the neural representations of briefly presented targets are combined and treated as a unitary, low resolution stimulus from which an orienting motor program is derived. The similarity of responses to double visual, double auditory, and bimodal stimuli suggests that a common sensorimotor mechanism applies within and between these sensory modalities.

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Stagg, Nicola J., Heriberto P. Mata, Mohab M. Ibrahim, Erik J. Henriksen, Frank Porreca, Todd W. Vanderah et T. Philip Malan. « Regular Exercise Reverses Sensory Hypersensitivity in a Rat Neuropathic Pain Model ». Anesthesiology 114, n^o 4 (1 avril 2011) : 940–48. http://dx.doi.org/10.1097/aln.0b013e318210f880.

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Background Exercise is often prescribed as a therapy for chronic pain. Short-term exercise briefly increases the production of endogenous analgesics, leading to transient antinociception. In limited studies, exercise produced sustained increases in endogenous opioids, sustained analgesia, or diminished measures of chronic pain. This study tests the hypothesis that regular aerobic exercise leads to sustained reversal of neuropathic pain by activating endogenous opioid-mediated pain modulatory systems. Methods After baseline measurements, the L5 and L6 spinal nerves of male Sprague-Dawley rats were tightly ligated. Animals were randomized to sedentary or 5-week treadmill exercise-trained groups. Thermal and tactile sensitivities were assessed 23 h after exercise, using paw withdrawal thresholds to von Frey filaments and withdrawal latencies to noxious heat. Opioid receptor antagonists were administered by subcutaneous, intrathecal, or intracerebroventricular injection. Opioid peptides were quantified using immunohistochemistry with densitometry. Results Exercise training ameliorated thermal and tactile hypersensitivity in spinal nerve-ligated animals within 3 weeks. Sensory hypersensitivity returned 5 days after discontinuation of exercise training. The effects of exercise were reversed by using systemically or intracerebroventricularly administered opioid receptor antagonists and prevented by continuous infusion of naltrexone. Exercise increased β-endorphin and met-enkephalin content in the rostral ventromedial medulla and the mid-brain periaqueductal gray area. Conclusions Regular moderate aerobic exercise reversed signs of neuropathic pain and increased endogenous opioid content in brainstem regions important in pain modulation. Exercise effects were reversed by opioid receptor antagonists. These results suggest that exercise-induced reversal of neuropathic pain results from an up-regulation of endogenous opioids.

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Cameron, Kristie Elizabeth, Jane De Garnham, Kristeen Jensen et Lewis A. Bizo. « Food Preference Predicts Speed of Approach on a Runway Task by Dogs ». Pet Behaviour Science, n^o 8 (5 juillet 2019) : 1–10. http://dx.doi.org/10.21071/pbs.v0i8.11179.

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The effective and quick assessment of food preference is important when attempting to identify foods that might function as effective reinforcers in dogs. In the current experiment a food preference assessment was conducted where more highly preferred foods were expected to be associated with faster approaches in a subsequent runway task. Eight dogs were tested in a paired preference assessment offering combinations of two of six types of raw food, including the dog’s staple diet, to identify a rank order of preference for the foods. A different raw food was offered as the staple in two preference tests. The results showed that the staple foods were not preferred as highly as the other foods and that each dog displayed unique and stable preferences for the different foods. In the runway task the dogs were required to walk five metres to obtain a small amount of their most preferred, least preferred or staple foods and latency of approach to the foods was recorded. The approach latencies were faster for their most preferred food compared to their least preferred and the staple foods. The use of a runway to assess reinforcer effectiveness combined an effortful behaviour to obtain food while also requiring the dogs to make a choice, thus precluding the need for more complicated and time-consuming methods of preference assessment. The application of this method for fast and effective identification of preferred reinforcers is currently being investigating further to inform pet owners of simple methods to increase their training successes. Owners of raw food fed dogs are advised to conduct a preference assessment to identify their dogs most preferred food for use as a reinforcer during training.

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Grangeon, Murielle, Kathleen Charvier, Aymeric Guillot, Gilles Rode et Christian Collet. « Using Sympathetic Skin Responses in Individuals With Spinal Cord Injury as a Quantitative Evaluation of Motor Imagery Abilities ». Physical Therapy 92, n^o 6 (8 mars 2012) : 831–40. http://dx.doi.org/10.2522/ptj.20110351.

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Background Motor imagery (MI) ability should be evaluated in selected individuals with spinal cord injury (SCI) who can benefit from MI training in their rehabilitation program. Electrodermal activity seems to be a reliable indicator for assessing MI ability. However, individuals with SCI have a variety of autonomic dysfunctions. Objective This study aimed to investigate electrodermal responses (EDRs) elicited by MI. Design A cost-utility analysis of EDR above and below the lesion level in individuals with complete or incomplete SCI (n=30) versus a control group of individuals who were healthy (n=10) was used. Method The EDR was recorded above and below the lesion level during MI of a drinking action. Duration, latency, and amplitude of EDR were the outcome measures. Results Hand and foot EDR in the control group occurred with the same pattern and similar latencies, suggesting a common efferent sympathetic pathway to sweat glands of the hand and foot mediating a sympathetic skin response. Individuals with SCI elicited responses above the lesion level. The EDR amplitude was correlated to the lesion level and autonomic dysreflexia history. No foot response was recorded in individuals with complete cervical and thoracic motor lesions. Foot response with a lower amplitude and higher latency occurred in participants with incomplete motor lesion, suggesting a link between the descending motor pathway and sympathetic function. Limitations The small sample of individuals with incomplete SCI limits the generalization of the results obtained at the foot site. Conclusions Electrodermal response above the lesion level may be a reliable index for assessing MI ability in individuals with SCI. It is a noninvasive, user-friendly method for clinicians to consider before enrolling individuals in MI training.

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Christou, C. G., et H. H. Bülthoff. « Scene Recognition after Active and Passive Learning ». Perception 26, n^o 1_suppl (août 1997) : 109. http://dx.doi.org/10.1068/v970374.

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Most research on visual recognition has been carried out on isolated objects with the main finding being that for certain classes of objects recognition strongly depends on the views learned during training. Recognition of scenes, ie structured environments, is rarely studied, possibly because of the difficulty involved in isolation and control of pertinent cues. We can overcome such problems by using computer graphics to model structured environments where training or learning is facilitated by active explorations with the use of VR technology. We are trying to determine whether there exists the same degree of view-dependence in scenes as has been found for objects. We do this by using a single, sparsely decorated, yet structured room with which subjects familiarise themselves. This learning process can take two forms: either active or passive. In the active case, subjects can manoeuvre in a restricted set of directions in order to find ‘hidden’ coded targets. In the passive case, fifty 2-D views of the room are presented to them in random sequence with some views containing embedded targets which they have to acknowledge. Correct responses and response latencies of eighteen subjects in each condition were recorded in subsequent (old/new) recognition tests. Performance for recognition from familiar directions was similar after active and passive learning (eg approx. 80% hits). However, we found that active learning facilitates recognition from unfamiliar directions ( d' active = 0.96; passive = 0.22). This superior performance after active learning could be due to the increased availability of 3-D information (eg from motion parallax during movement). We are therefore testing this using binocular disparity as a depth cue during passive learning.

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Gusev, Pavel A., et Daniel L. Alkon. « Intracellular Correlates of Spatial Memory Acquisition in Hippocampal Slices : Long-Term Disinhibition of CA1 Pyramidal Cells ». Journal of Neurophysiology 86, n^o 2 (1 août 2001) : 881–99. http://dx.doi.org/10.1152/jn.2001.86.2.881.

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Despite many advances in our understanding of synaptic models of memory such as long-term potentiation and depression, cellular mechanisms that correlate with and may underlie behavioral learning and memory have not yet been conclusively determined. We used multiple intracellular recordings to study learning-specific modifications of intrinsic membrane and synaptic responses of the CA1 pyramidal cells (PCs) in slices of the rat dorsal hippocampus prepared at different stages of the Morris water maze (WM) task acquisition. Schaffer collateral stimulation evoked complex postsynaptic potentials (PSP) consisting of the excitatory and inhibitory postsynaptic potentials (EPSP and IPSP, respectively). After rats had learned the WM task, our major learning-specific findings included reduction of the mean peak amplitude of the IPSPs, delays in the mean peak latencies of the EPSPs and IPSPs, and correlation of the depolarizing-shifted IPSP reversal potentials and reduced IPSP-evoked membrane conductance. In addition, detailed isochronal analyses revealed that amplitudes of both early and late IPSP phases were reduced in a subset of the CA1 PCs after WM training was completed. These reduced IPSPs were significantly correlated with decreased IPSP conductance and with depolarizing-shifted IPSP reversal potentials. Input-output relations and initial rising slopes of the EPSP phase did not indicate learning-related facilitation as compared with the swim and naı̈ve controls. Another subset of WM-trained CA1 PCs had enhanced amplitudes of action potentials but no learning-specific synaptic changes. There were no WM training-specific modifications of other intrinsic membrane properties. These data suggest that long-term disinhibition in a subset of CA1 PCs may facilitate cell discharges that represent and record the spatial location of a hidden platform in a Morris WM.

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Pereira, Talmo D., Nathaniel Tabris, Arie Matsliah, David M. Turner, Junyu Li, Shruthi Ravindranath, Eleni S. Papadoyannis et al. « SLEAP : A deep learning system for multi-animal pose tracking ». Nature Methods 19, n^o 4 (avril 2022) : 486–95. http://dx.doi.org/10.1038/s41592-022-01426-1.

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AbstractThe desire to understand how the brain generates and patterns behavior has driven rapid methodological innovation in tools to quantify natural animal behavior. While advances in deep learning and computer vision have enabled markerless pose estimation in individual animals, extending these to multiple animals presents unique challenges for studies of social behaviors or animals in their natural environments. Here we present Social LEAP Estimates Animal Poses (SLEAP), a machine learning system for multi-animal pose tracking. This system enables versatile workflows for data labeling, model training and inference on previously unseen data. SLEAP features an accessible graphical user interface, a standardized data model, a reproducible configuration system, over 30 model architectures, two approaches to part grouping and two approaches to identity tracking. We applied SLEAP to seven datasets across flies, bees, mice and gerbils to systematically evaluate each approach and architecture, and we compare it with other existing approaches. SLEAP achieves greater accuracy and speeds of more than 800 frames per second, with latencies of less than 3.5 ms at full 1,024 × 1,024 image resolution. This makes SLEAP usable for real-time applications, which we demonstrate by controlling the behavior of one animal on the basis of the tracking and detection of social interactions with another animal.

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