Differential neuropsychological profiles in children and adolescents with motor disability in an inclusive educational setting.

The aim of this study was to determine the potential cognitive impairment associated with motor disability in a group of children attending regular schools and to analyze whether there were different cognitive profiles according to the type of motor disability they presented. The study had 87 participants, 31 healthy and 56 with three types of motor disability: Neuromuscular Diseases (NMD Group), Cerebral Palsy-Hemiparesis (CP- HPx Group) and Cerebral Palsy-Diplegia (CP-DP). Ages ranged from 6 to 18 years and they had medium and medium-high socioeconomic and cultural levels. All participants attended regular state-funded and independent schools in an inclusive modality. The neuropsychological assessment included the following cognitive domains: processing speed, working memory, verbal and visual episodic memory, language, visuo-perception and constructive praxis and executive functioning. A second analysis was performed with the groups with CP: one based on the severity of gross motor impairment (GMFCS-E&R scale) and the other based on the levels of manual dexterity (MACS scale). ANCOVAs were performed controlling for age and processing speed in the three analyses. The group with CP-HPx was shown to be the most cognitively impaired of the three groups, with significant deficits in visuo-perception, verbal working memory, and visuo-spatial memory. Subjects with greater gross motor dysfunction (GMFCS-E&R) did not show the greatest cognitive impairment, while those with worse manual dexterity (MACS) exhibited greater cognitive impairment. Children and adolescents with motor disabilities, a priori cognitively normal, present different levels of cognitive impairment. This should be considered when planning educational adaptations for this infant-juvenile population.

Analysis of Convergent Validity of Performance-Based Activities of Daily Living Assessed by PA-IADL Test in Relation to Traditional (Standard) Cognitive Assessment to Identify Older Adults with Mild Cognitive Impairment.

Difficulty in performing instrumental activities of daily living (IADLs) is currently considered an important indicator of cognitive impairment in the elderly. A non-experimental case-control investigation was conducted to assess the convergent validity of the PA-IADL with traditional (standard) cognitive assessment tests in its ability to identify adults with mild cognitive impairment. The analysis of the data was carried out by means of various multivariate statistical tests, and the sequence in its execution led to the conclusion that 8 of the 12 Tasks that make up the PA-IADL allow for the identification of people with mild cognitive impairment (MCI) to the same extent as traditional cognitive assessment tests and regardless of age. Age was found to be a moderating variable in the performance of the eight tasks; however, the results allow us to hypothesize that people with MCI experience a significant decline when it happens but thereafter, the deterioration that occurs does so at the same rate as the deterioration experienced by healthy people. They also allow us to hypothesize that the difference in the cognitive skills required by the eight functional tasks, and therefore also in the cognitive skills required by the traditional (standard) tests of a person with MCI compared to a person of the same age without MCI (Healthy), is approximately 10 years. These hypotheses have remarkable relevance and should be tested via longitudinal research. In the meantime, the results highlight the importance of the IADL assessment for the diagnosis of MCI as a complement to the standard cognitive assessment.

Aging Does Not Enhance Social Contagion Effect.

Studies on the social contagion of memory show that it is possible to create false memories from the wrong responses from other people without requiring their physical presence. The current study examined age differences between false memories via the modified social contagion paradigm. Twenty older and twenty younger adults were shown six household scenes and were exposed to the erroneous memory reports of an implied confederate who was not physically present. The presentation time of the scenes and the typicality of the contagion items were manipulated. The participants watched each scene individually and then took turns giving their recall responses with the responses belonging to a fictional participant provided by written cards. The results in a final individual recall test indicated a significant contagion effect in both groups of participants. Additionally, an effect of the typicality of the contagion items was observed, such that the more typical items produced more contagion than the less typical items. In relation to true recall, the older adults remembered significantly fewer items from the scenes than the younger ones and obtained a lower score in the word list subtest of the Weschler Memory Scale. Although the older group had an episodic memory deficit, they were not more susceptible to being affected by the wrong responses of other people than younger group.

ERP and behavioural measures of cognitive effort associated to forget negative and neutral words.

The cognitive effort associated with remembering (R) vs forgetting (F) neutral and negative words was analyzed through a visual detection task integrated in an item-method directed forgetting task. Thirty-three younger adults participated in the experiment while their electrophysiological activity was registered in the study phase. The results shown: (1) negative words evoked more positive ERPs than neutral words on frontal regions, suggesting a preferential processing of negative words. (2) F-cues evoked more positive ERPs than R-cues did for neutral rather than negative words between 500 and 900 ms. This effect could reflect the difficulty in implementing inhibitory mechanisms on negative words. (3) At visual detection task, RTs for post-F probes were longer than for post-R probes. In 350-550 ms time window, ERPs were more positive for post-F probes than post-R probes in over right frontal regions and left medial parietal regions. Additionally, larger P2 were evoked by post-F negative probes than by post-R negative and post-F neutral ones. (4) In recognition test, participants recognized more negative TBF words than neutral ones. The ERP and behavioral results indicate that forgetting is more difficult than remembering, especially when words have a negative content, which implies a greater recruitment of parietal and frontal regions.

Atividade antibacteriana de plantas úteis e constituintes químicos da raiz de Copernicia prunifera / Antibacterial activity of useful plants and chemical constituents of the roots of Copernicia prunifera

Extratos etanólicos de Qualea grandiflora e Copernicia prunifera e extrato hexânico de Dipteryx lacunifera foram avaliados quanto a atividade antibacteriana, utilizando ensaios de difusão a partir de orifício e concentração inibitória mínima (CIM), frente a cepas Gram positivas e Gram-negativas, incluindo espécies multidroga resistentes. O extrato de Q. grandiflora apresentou atividade moderada para as cepas de Staphylococcus epidermidis (CIM = 500 µg/mL) e atividade fraca sobre as demais bactérias Gram-positivas testadas e inativo sobre bactérias Gram-negativas. Os resultados obtidos com S. epidermidis apesar de moderados são importantes, uma vez que este microorganismo é o principal causador de bacteremias e sepse associada com dispositivos médicos implantados. gama-Tocoferol e a mistura de sitosterol e estigmasterol foram isolados do extrato etanólico de raiz de C. prunifera e as estruturas destes compostos foram identificadas com base na análise dos dados espectrais de RMN e comparação com a literatura.

Ethanol extracts of Qualea grandiflora and Copernicia prunifera and hexane extract of Dipteryx lacunifera were evaluated by diffusion in agar and minimum inhibitory concentration (MIC) against Gram-positive and Gram-negative bacteria including multiresistant drug strains. The extract of Q. grandiflora presented moderate activity for Staphylococcus epidermidis (MIC = 500 µg/mL) and weak activity against other Gram-positive strains and inactive for Gram-negative species. The results obtained for S. epidermidis despite being moderate are important because this pathogen is often recovered from bacteremia and sepsis from infections of implanted devices. gamma-Tocopherol and the mixture of sitosterol and stigmasterol were isolated from the ethanol extract of the roots of C. prunifera. The structures of these compounds were identified by NMR spectroscopy and comparison with literature data.

Attentional dysfunction of the central executive in AD: evidence from dual task and perseveration errors.

This study examined the capacity of 27 Alzheimer's disease (AD) patients to divide attention between two simultaneous tasks, as compared to 27 elderly controls. In order to determine whether distribution of attention is affected by age, a younger group was included. The results showed a marked impairment in the capacity of the AD patients to combine performance in two simultaneous tasks compared to the elderly controls, but the latter group did not differ from the younger participants, indicating a disease rather than an age effect, and replicating the results of Baddeley et al. (2001). The present study also analysed whether perseverations committed in a previous study (Sebastian et al., 2001) by some AD and elderly control participants in the Brown-Peterson (B-P) task (Brown, 1958; Peterson and Peterson, 1959) were related to their attentional capacity in the dual task. Although the elderly controls committed perseveration errors, a negative correlation was only found in the AD group between the index of attention distribution in the dual task and the frequency of perseverations in the B-P task. Our results would therefore suggest that AD patients show a dysfunction of the central executive and/or a deficit in their ability to allocate cognitive resources. This could be interpreted in terms of problems in updating the contents of working memory and suppressing activation of no-longer-relevant information in the early stages of AD, leading to perseveration errors in the B-P task.

Predictive validity of event-related potentials (ERPs) in relation to the directed forgetting effects.

OBJECTIVE: A directed forgetting paradigm (word method) was used to assess the relationships between the event-related potentials (ERPs) recorded during the study phase and the subsequent forgetting effects. METHODS: In the study phase 100 words were presented each followed by either an instruction to remember (R) or to forget (F). Then these 100 words, together with another 100 new words, were presented and subjects had to perform an old/new decision task. The forgetting effect was considered as the difference between the rate of R- and F-words correctly recognised. Based on this difference, the whole sample was divided into two 10-subject groups with high and low forgetting effect. RESULTS: From 300 to 600 msec post-instruction differences in ERPs between R and F instructions were similar in both groups. In contrast, in the 100-300 msec epoch, ERP differences only appeared in the high-effect group and consisted of an enhanced positive activity elicited by F instruction at frontal and prefrontal areas and a larger positivity associated to R instruction at parietal area. CONCLUSIONS: The findings suggest that the processing of the word is kept on stand-by until the instruction is provided. Instruction to remember would reactivate this processing, which would mainly involve the parietal area, whereas instruction to forget appears to trigger frontal and prefrontal mechanisms trying to inhibit such processing.

Patterns of errors in short-term forgetting in AD and ageing.

This study examined whether the low performance of 40 AD patients in the Brown-Peterson task could be explained by a pattern of errors that differed from 55 elderly controls. Our quantitative results showed that AD patients had a lower performance level in the three retention intervals than controls but a significant interaction between group and interval was not found, indicating that the rate of forgetfulness was similar in the two groups. In our qualitative analysis, errors were categorised as confusions, perseverations, omissions, and order alterations. Contrary to other studies (Dannenbaum, Parkinson, & Inman, 1988; Kopelman, 1985) where an AD forgetfulness tendency of omissions was observed, our data showed an excess of perseveration (even more than five repetitions), indicating problems in the central executive. This could be interpreted in terms of problems in updating the contents of working memory.