Cognitive and behavioral profiles of pediatric surgical candidates with frontal and temporal lobe epilepsy.

BACKGROUND: We aimed to prospectively analyze memory and executive and social cognitive functioning in patients with drug-resistant frontal lobe epilepsy (FLE) and temporal lobe epilepsy (TLE) with focal lesions and isolate the impact of intellectual ability on specific deficits. METHODS: A neuropsychological evaluation was performed in 23 children with FLE, 22 children with TLE, and 36 healthy pediatric controls (HCs). Patients in the epilepsy groups had a range of lesions, including low-grade epilepsy-associated tumors (LEAT), focal cortical dysplasia (FCD) type II, and mesial temporal sclerosis (MS). RESULTS: There were no significant differences between children with FLE and TLE regarding memory, executive, or social cognitive functioning. General Ability Index (GAI) was a predictor of memory, executive function, and social cognition scores and was influenced by age at onset, duration of epilepsy, and number of antiepileptic drugs (AEDs) prescribed at the time of assessment. Working Memory Index scores of patients with TLE, which measure verbal mnesic processing, were significantly lower than those of HCs and patients with TLE. The greatest differences in both clinical groups compared to HCs were recorded in cognitive executive functions, and patients with FLE had lower scores in this domain. Regarding behavioral executive functions, patients with TLE presented impaired emotional control and impulse inhibition and patients with FLE exhibited decreased flexibility. CONCLUSION: Consistent with previous research, our findings provide further detailed evidence of small differences in cognitive performance among children with FLE and TLE. These differences emerge on analysis of the factors with which deficits are associated.

[Types of semantic category and stimulus modality in procedural learning: implications for models of semantic memory]. / Tipos de categoría semántica y modalidad de los estímulos en el aprendizaje procedimental: implicaciones sobre los modelos de memoria semántica.

The present work attempts to determine whether procedural learning of a semantic categorisation task is influenced by the type of semantic category of the stimuli (biological and non-biological elements). It is also an attempt to determine the effect of the stimulus presentation modality on the categorisation task. A semantic categorisation task (4 series of 40 stimuli) was administered to 256 participants (128 classifying pictures, and 128 classifying words). Biological categories were responded to faster than non-biological ones although there were no significant differences between the interaction of the category type and the stimulus presentation modality. Reaction times progressively decreased with practice. However, the initial differences disappeared when subjects were trained. The way that current models account for these investigation findings is discussed. In addition, it is suggested that there is an attentional bias in favor of biological elements, which disappears when presumably less relevant elements become more relevant as a function of the task characteristics.

Schoolchildren's Compensatory Strategies and Skills in Relation to Attention and Executive Function App Training.

BACKGROUND: Given the importance of attention and executive functions (EF) in children's behavior, programs aimed at improving these processes are of special interest. Nexxo-training combines the use of the Nexxo touchscreen application (inhibition and vigilance tasks) with procedural metacognitive strategies (imparted by an instructor) for all the individuals using the app, regardless of their level of ability, plus compensatory strategies based on individual child performance. This study presents an analysis of the compensatory strategies that schoolchildren (aged 6-8 years old) receive when experiencing difficulties with EF tasks, in addition to an analysis of the developmental factors and cognitive skills that may modulate EF task performance. METHODS: For this study, we use data from a previous randomized active-controlled study (under review), in which forty-six typically developing children aged between 6 and 8 years old (24 girls/22 boys) were enrolled in the training group. The selected children were in the 1st grade (n = 28, x ¯ = 78.32 ± 4.037 months) and 3rd grade of primary education (n = 18, x ¯ = 102.11 ± 3.445). We collected data on EF training performance, compensatory strategies needed and neuropsychological assessments. RESULTS: A total of 80.43% participants required some form of compensatory strategy during training. Regarding required compensatory strategies, those who had lower scores in EF training needed more compensatory strategies, in particular, instructional comprehension (r = -0.561, p < 0.001 for inhibition-tasks; r = -0.342, p < 0.001 for vigilance-tasks). Concerning developmental factors, age significantly predicted better performance in both EF tasks (ß = 0.613, p < 0.001 for inhibition; ß = 0.706, p < 0.001 for attention). As regards task performance, those with better performance in inhibition tasks also had better performance in vigilance tasks (r = 0.72, p < 0.001). Finally, regarding cognitive skills, participants with higher performance in fluid intelligence (Q1, n = 12) had higher scores (U = 14.5, p < 0.05) than the group with the lowest performance (Q4, n = 11) in vigilance. CONCLUSION: As previous literature suggests, inhibition is one of the core processes of EF. Therefore, we should focus training on the core EF processes. Inhibition and vigilance are closely related processes. In terms of the use of compensatory strategies, these are more needed for participants with lower levels of performance in inhibition or vigilance. Regarding strategy analysis, instructional comprehension and self-instruction (goal setting and planning) seem to be the most useful strategies for those with difficulties in inhibitory and vigilance task performance. Regarding development, as expected, age moderates task performance in inhibition and attention. Finally, cognitive skills, such as fluid intelligence and cognitive flexibility, predicted better results in attention. EF training using not only an app, but also compensatory strategies based on user performance, is a new research direction offering more opportunities to generalize EF training in everyday life.

Brain Training in Children and Adolescents: Is It Scientifically Valid?

Background: Brain training products are becoming increasingly popular for children and adolescents. Despite the marketing aimed at their use in the general population, these products may provide more benefits for specific neurologically impaired populations. A review of Brain Training (BT) products analyzing their efficacy while considering the methodological limitations of supporting research is required for practical applications. Method: searches were made of the PubMed database (until March 2017) for studies including: (1) empirical data on the use of brain training for children or adolescents and any effects on near transfer (NT) and/or far transfer (FT) and/or neuroplasticity, (2) use of brain training for cognitive training purposes, (3) commercially available training applications, (4) computer-based programs for children developed since the 1990s, and (5) relevant printed and peer-reviewed material. Results: Database searches yielded a total of 16,402 references, of which 70 met the inclusion criteria for the review. We classified programs in terms of neuroplasticity, near and far transfer, and long-term effects and their applied methodology. Regarding efficacy, only 10 studies (14.2%) have been found that support neuroplasticity, and the majority of brain training platforms claimed to be based on such concepts without providing any supporting scientific data. Thirty-six studies (51.4%) have shown far transfer (7 of them are non-independent) and only 11 (15.7%) maintained far transfer at follow-up. Considering the methodology, 40 studies (68.2%) were not randomized and controlled; for those randomized, only 9 studies (12.9%) were double-blind, and only 13 studies (18.6%) included active controls in their trials. Conclusion: Overall, few independent studies have found far transfer and long-term effects. The majority of independent results found only near transfer. There is a lack of double-blind randomized trials which include an active control group as well as a passive control to properly control for contaminant variables. Based on our results, Brain Training Programs as commercially available products are not as effective as first expected or as they promise in their advertisements.

A randomized placebo controlled clinical trial to evaluate the efficacy and safety of minocycline in patients with Angelman syndrome (A-MANECE study).

BACKGROUND: Minocycline is an old tetracycline antibiotic that has shown antiinflammatory and antiapoptotic properties in different neurological disease mouse models. Previous single arm study in humans demonstrated benefits in individuals with Angelman Syndrome (AS); however, its efficacy in patients with Angelman Syndrome has not been assessed in a controlled trial. This was a randomized, double-blind, placebo-controlled, crossover trial in individuals with AS, aged 6 years to 30 years (n = 32, mean age 12 [SD 6·29] years). Participants were randomized to minocycline or placebo for 8 weeks and then switched to the other treatment (a subset of 22 patients) or to receive minocycline for up to 16 weeks (10 patients). After week 16, all patients entered a wash-out 8-week follow-up period. RESULTS: Thirty-six subjects were screened and 34 were randomized. Thirty two subjects (94·1%) completed at least the first period and all of them completed the full trial. Intention-to-treat analysis demonstrated the lack of significantly greater improvements in the primary outcome, mean changes in age equivalent of the development index of the Merrill-Palmer Revised Scale after minocycline compared with placebo (1·90 ± 3·16 and 2·00 ± 3·28, respectively, p = 0·937). Longer treatment duration up to 16 weeks did not result in better treatment outcomes (1·86 ± 3·35 for 8 weeks treatment vs 1·20 ± 5·53 for 16 weeks treatment, p = 0·667). Side effects were not significantly different during minocycline and placebo treatments. No serious adverse events occurred on minocycline. CONCLUSIONS: Minocycline treatment for up to 16 weeks in children and young adults with AS resulted in lack of significant improvements in development indexes compared to placebo treatment. Treatment with minocycline appears safe and well tolerated; even if it cannot be completely ruled out that longer trials might be required for a potential minocycline effect to be expressed, available results and lack of knowledge on the actual mechanism of action do not support this hypothesis. TRIAL REGISTRATION: European Clinical Trial database ( EudraCT 2013-002154-67 ), registered 16th September 2013; US Clinical trials database ( NCT02056665 ), registered 6th February 2014.

Brain dynamics of Arabic reading: a magnetoencephalographic study.

Arabic writing differs greatly from western scripts. To evaluate the influence of written Arabic on the pattern of language-related brain activation, a group of native Arab speakers and a control group of native Spanish speakers were scanned with magnetoencephalography during a reading task. In both groups, brain activity was strongly left lateralized during the time window between 200 and 500 ms after stimulus onset. During late latencies (beyond 500 ms), however, the right and the left hemispheres reached a similar activation level in the Arabic but not in the Spanish group. This suggests a time-dependent role of both hemispheres during Arabic language reading.

Prefrontal brain magnetic activity: effects of memory task demands.

Changes in spatiotemporal profiles of brain magnetic activity were investigated in healthy volunteers as a function of varying demands for phonological storage of spoken pseudowords. Greater activity for the phonological memory task was restricted to the dorsolateral prefrontal cortex (DLPFC) in the left hemisphere. During performance of the memory task, activity was initially found in the left superior temporal gyrus (between 100 and 200 ms), followed by activity in the ventrolateral prefrontal, motor, and premotor cortices (between 200 and 300 ms). Activity in DLPFCs was first observed consistently across participants later, between 300 and 400 ms. The data are consistent with the purported role of posterior temporal cortices in phonological analysis and in the online storage of phonological information, the contribution of ventrolateral and motor processing areas in establishment and short-term maintenance of articulatory representations through rehearsal, and the role of DLPFCs in the executive control of the maintenance operation.

Modulation of brain magnetic activity by different verbal learning strategies.

In this study we examined spatiotemporal profiles of brain activity in the context of tasks designed to engage different verbal learning strategies (serial order, phonological, and semantic). The profile of activation associated with the serial-order strategy, which resulted in poor recall performance, featured early activation of the inferior frontal, sensorimotor, and insular region in the left hemisphere, between 200 and 400 ms after stimulus onset. Subsequently, activation was more prominent in dorsolateral prefrontal cortices bilaterally. In contrast, activation profiles associated with the phonological strategy featured predominantly activation of the superior temporal gyrus in the left hemisphere between 500 and 600 ms. Predominant activation of the left middle temporal gyrus, between 500 and 700 ms, was the key feature of the activation profile observed when the semantic elaboration strategy was utilized. These results suggest that different brain circuits are engaged to support learning of new verbal information as a function of the level and type of initial processing applied to the stimuli.