Littérature scientifique sur le sujet « "training latencies" »

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.

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.

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.

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.

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.

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.

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.

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.

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/

SUMMARY This work is part of research on early childhood education and it takes up and develops studies that have investigated the relationships between adults (parents and educators) and between children and adults in ECEC settings in particular. The aim was to investigate the interactive dynamics that develop between parents, educators and children during transitions from the family to the school context (morning arrival and early afternoon leaving), linking microanalytical interaction analysis with the exploration of interpretation processes by the educators involved. The assumption is that moments of "ecological transition" (Bronfenbrenner, 1979), when parents and educators share and negotiate the transfer of educational responsibilities regarding the child, are atypical moments in the daily routines at school, creating the opportunity for focusing on the interactions between parents and educators in the presence of children, thus creating privileged educational opportunities that make the ideas and meanings attributed to these interactions by the protagonists themselves emerge in a more "natural" way. Numerous studies have focused on teaching the specificity of these transition events (Barbieri et al., 1983, Angelini et al., 1983, Maltempi, 1986, Comotti, Varin, 1988, Varin, Crugnola Riva, 1996) and their central role in building good relationships between services and families (Milani, 2009), drawing attention to the role of observing interaction in teacher training. Research in the ECEC, in particular, has highlighted the need to support educators so that they are builders of rituals and routines which support the separation between parent and child, consistent with the relationship style (Mantovani, Saitta, Bove, 2000, Carli, 2002). However, in theory, almost all studies that have investigated this dimension refer to dyadic relational types (i.e. focused on the parent-child or teacher-child pair), often based on studies which refer to attachment theory (Bowlby, 1973, Ainsworth et al.,1978) and rarely have they included observing behavior to reveal the subjective ideas of the adults involved. The challenge is to go back and study these moments, guided by the theoretical and methodological indications that emerge from the most recent psychological research on how to analyze the micro-processes involved in interaction dynamics in educational settings, adopting a triadic, process-oriented perspective (Fivaz-Depeursinge, Corboz-Warnery, 1999, Tremblay- Leveau, 1999; Simonelli et al., 2012). The authors suggest reinterpreting micro-analytic observation in a pedagogical perspective, since it can help expand educational research regarding these issues in a situated, rigorous yet relevant way for training the teachers involved. Through observing interactions in a triadic perspective, this thesis considers the educationally relevant possibility of focusing not so much, or not only, on the (temporary) separation of the parent-child pair. The micro-processes of transition and confidence in the teacher-parent-child triad, their mutual positions, alliances, or dis-alliances are considered educational. Attention is also placed on the factors that make transition dynamics more or less smooth. At the same time, the study adopts a phenomenological, micro-pedagogical perspective (Bertolini, 1997, Mortari, 2007, Caronia, 2011) (Demetrio, 1992) and describes the interactive dynamics in light of the micro-analytical meanings assigned to them by the protagonists (Stern, 1995, 2004) in an attempt to put the observed behavior in relation to the more "hidden" ideas and educational models. From a methodological point of view, the study follows the field research tradition in education (Lumbelli, 1980, Mantovani, 1998) and combines qualitative research tools (focus groups, interviews, observations) with some recent methodological innovations, developed in the field of video research, using video in educational contexts (Goldman et al., 2007, Bove, 2008, 2009). In this sense, the study can be understood as a "pilot study on the method", since it explores the "training latencies" (Bove, 2009) of the tools and methods used, examining the importance of pedagogical training microanalysis and video, and in particular the microanalysis of interaction. These tools seem to offer interesting implications for extended reflection and research in educational services. Perhaps they can focus attention on micro-interactive processes, thereby bringing out the ideas of educators, facilitating the detailed study of reflexivity process practices which can link knowing-observing with the cognitive-interpretive-reflective sphere. This idiographic study was conducted at an ECEC in Parma with the following objectives: to observe, describe and analyze the interactive and relational dynamics patterns that developed between adults (parents, teachers) and children during transition to school from a microanalytical perspective; to gather the ideas of educators on some specific transition episodes, stimulating microanalytical reconstruction processes; to explore the educational potential of a mixed methodological approach (visual and narrative) based on behavior observation descriptions and reflection regarding the meanings ascribed to them by educators, who were the protagonists. In general, we aimed at pedagogically focusing on moments of "home-school transition" to help reduce the distance that often separates the discourses of educators regarding the relationship with the family from the daily practices put into effect in contexts, re-centering the attention of educators on their roles and their responsibilities and to observe the interactive competence of children and parents. Empirically, the research was divided into three phases, each involving the teachers in the ECEC, which was the research context, during different moments of observation and reflection on their individual and intersubjective behaviors. In the first stage, we explored the ideas and conceptions of the teachers about education by conducting informal interviews, group discussions and participant observations. During the second phase, we explored the teachers' ideas regarding interaction with children and parents in greater depth through microanalytic interviews - echoing the method originally developed by Stern (1995) - aimed at fostering the narration of transition episodes deemed more or less "positive" by the teachers themselves. At the same time, were observed and videotaped 100 episodes of the "input and output" of the children and their parents, 40 hours of which were subsequently selected as a representative sample for the microanalysis of the interactions observed, in an effort to identify patterns or recurring patterns of interaction. Finally, during the third phase of research, the teachers involved in the video recordings were invited to participate in an exercise in order to reconstruct their critical-reflexive behaviors mediated by images, to make them more aware by observing and analyzing the dynamic interaction processes and reflecting on their behavior and their assumptions. The data analysis (visual and narrative) made it possible to highlight the following aspects: - First, the microanalysis of the observed situations focused on the complexity of these transition moments, highlighting the role of teachers and the often non-verbal interactive skills of very young children; - Analysis of discourses, and therefore the meanings, collected during the interviews and the subsequent discussion with the teachers about the videos showed the changes in how the protagonist-teachers commented on and interpreted their roles in welcoming the children to school, including their reconsideration of the competences of children and parents. Overall, the results of this study allow us to confirm the educational value of the videomicroanalysis of interactions, which could also be further developed with respect to its impact on the behavior of educators.