977 resultados para mental performance


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It has been shown that mental rotation of objects and human body parts is processed differently in the human brain. But what about body parts belonging to other primates? Does our brain process this information like any other object or does it instead maximize the structural similarities with our homologous body parts? We tried to answer this question by measuring the manual reaction time (MRT) of human participants discriminating the handedness of drawings representing the hands of four anthropoid primates (orangutan, chimpanzee, gorilla, and human). Twenty-four right-handed volunteers (13 males and 11 females) were instructed to judge the handedness of a hand drawing in palm view by pressing a left/right key. The orientation of hand drawings varied from 0º (fingers upwards) to 90º lateral (fingers pointing away from the midline), 180º (fingers downwards) and 90º medial (finger towards the midline). The results showed an effect of rotation angle (F(3, 69) = 19.57, P < 0.001), but not of hand identity, on MRTs. Moreover, for all hand drawings, a medial rotation elicited shorter MRTs than a lateral rotation (960 and 1169 ms, respectively, P < 0.05). This result has been previously observed for drawings of the human hand and related to biomechanical constraints of movement performance. Our findings indicate that anthropoid hands are essentially equivalent stimuli for handedness recognition. Since the task involves mentally simulating the posture and rotation of the hands, we wondered if "mirror neurons" could be involved in establishing the motor equivalence between the stimuli and the participants' own hands.

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This study was aimed to evaluate the behaviour of eighteen clones of Hevea brasiliensis (rubber) against South American leaf blight and tostudy progress of the disease. The experiment was conducted in Cachoeiro de Itapemirim-ES, where 18 clones were evaluated. The experi-mental design was a randomized block with four replicates; each experimental unit consisted of three plants. Evaluations were performed at15-day intervals on 30 leaflets per tree. Disease incidence was quantified and infection classified according to the stages of development andtype of damage. Leaf blight occurred during the entire experimental period; however, disease intensity varied with the resistance level of theclones and the time of year. Clones FX 3864, RRIM 725, RRIM 711, IAC 300 and IAN 873 exhibited the highest resistance to leaf blight.

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Background: Studies on functional capacity in community-dwelling older people have shown associations between declines in instrumental activities of daily living (IADL) and several factors. Among these, age has been the most consistently related to functional capacity independent of other variables. We aimed at evaluating the performance of a sample of healthy and cognitively intact Brazilian older people on activities of daily living and to analyze its relation to social-demographic variables. Methods: We conducted a secondary analysis of data collected for previous epidemiological studies with community-dwelling subjects aged 60 years or more. We selected subjects who did not have dementia or depression, and with no history of neurological diseases, heart attack, HIV, hepatitis or arthritis (n = 1,111). Functional capacity was assessed using the Brazilian version of the Older American Resources and Services Questionnaire (BOMFAQ). ADL performance was analyzed according to age, gender, education, and marital status (Pearson's chi(2), logistic regression). Results: IADL difficulties were present in our sample, especially in subjects aged 80 years or more, with lower levels of education, or widowed. The logistic regression analysis results indicated that "higher age" and "lower education" (p <= 0.001) remained significantly associated with IADL difficulty. Conclusions: Functional decline was present in older subjects even in the absence of medical conditions and cognitive impairment. Clinicians and researchers could benefit from knowing what to expect from older people regarding IADL performance in the absence of medical conditions.

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Objective: To provide normative data for healthy middle-aged and elderly Brazilians' performance on the Addenbrooke Cognitive Examination-Revised (ACE-R) and to investigate the effects of age, sex, and schooling on test performance. Background: The ACE-R is a brief cognitive battery that assesses various aspects of cognition. Its 5 subdomains (Attention and Orientation, Memory, Verbal Fluency, Language, and Visuospatial Abilities) are commonly impaired in Alzheimer disease or frontotemporal dementia. Methods: We evaluated 144 cognitively healthy volunteers (50% men, 50% women) aged 50 to 93 years, with 4 to 24 years of schooling. We divided the participants into 4 age groups, each of which was then stratified into 3 groups according to years of education. We assessed all participants with the ACE-R, the Mattis Dementia Rating Scale, and the Cornell Scale for Depression in Dementia. Results: Years of education affected all ACE-R subscores. Age influenced the Verbal Fluency subscore (P < 0.001) and the ACE-R total score (P < 0.05). Sex affected the Attention and Orientation (P = 0.037) and Mini-Mental State Examination subscores (P = 0.048), but not the ACE-R total score (P > 0.05). Conclusions: The performance of healthy middle-aged and elderly individuals on the ACE-R battery is strongly influenced by education and, to a lesser extent, by age. These findings are of special relevance in countries with populations that have marked heterogeneity in educational levels.

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The aim of this study was to compare behavioral profile and school performance of school-age children living with a mother who presents clinical history of recurrent depression, diagnosed according to CID-10 criteria in order to verify the influences of such adversity. Thirty-eight mother-child dyads were evaluated using tests, interviews and questionnaires. Approximately two-thirds of the children presented behavioral and school performance difficulties with predominance of emotional and relationship problems, and impairment in the three areas of school performance which were assessed (writing, arithmetic and reading). Such difficulties may be associated with the negative impact of maternal depression. One-third of the children did not present difficulties, which suggests the use of protective mechanisms. The study highlights the importance of considering differences in children's profiles for the planning of mental health practices.

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Objectives: To assess the relationship between the CHS frailty criteria (Fried et al., 2001) and cognitive performance. Design: Cross sectional and population-based. Setting: Ermelino Matarazzo, a poor sub district of the city of Sao Paulo, Brazil. Participants: 384 community dwelling older adults, 65 and older. Measurements: Assessment of the CHS frailty criteria, the Brief Cognitive Screening Battery (memorization of 10 black and white pictures, verbal fluency animal category, and the Clock Drawing Test) and the Mini-Mental State Examination (MMSE). Results: Frail older adults performed significantly lower than non-frail and pre frail elderly in most cognitive variables. Grip strength and age were associated to MMSE performance, age was associated to delayed memory recall, gait speed was associated to verbal fluency and CDT performance, and education was associated to CDT performance. Conclusion: Being frail may be associated with cognitive decline, thus, gerontological assessments and interventions should consider that these forms of vulnerability may occur simultaneously.

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Determinants of cognitive performance in old age have received limited attention in Latin America. We investigated the association of socio-demographic and health-related variables with cognitive performance in a sample of older adults with limited educational experience living in a poor subdistrict of the city of Sao Paulo. This was a cross-sectional population-based study which included a sample of 384 seniors 65 years and older. Cognition was assessed by the Mini-Mental State Examination (MMSE) and the Brief Cognitive Screening Battery (BCSB) (episodic memory test with 10 pictures, verbal fluency (VF), Clock Drawing Test (CDT)). Results indicated that age, sex, schooling, depressive symptoms, and systolic blood pressure (SBP) level had a significant impact on the cognitive performance of the sample. Therefore, pharmacological and psychosocial interventions with a focus on improving mood and controlling hypertension may have beneficial effects on cognition among seniors with similar socio-demographic characteristics. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

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Background: In normal aging, the decrease in the syntactic complexity of written production is usually associated with cognitive deficits. This study was aimed to analyze the quality of older adults' textual production indicated by verbal fluency (number of words) and grammatical complexity (number of ideas) in relation to gender, age, schooling, and cognitive status. Methods: From a probabilistic sample of community-dwelling people aged 65 years and above (n = 900), 577 were selected on basis of their responses to the Mini-Mental State Examination (MMSE) sentence writing, which were submitted to content analysis; 323 were excluded as they left the item blank or performed illegible or not meaningful responses. Education adjusted cut-off scores for the MMSE were used to classify the participants as cognitively impaired or unimpaired. Total and subdomain MMSE scores were computed. Results: 40.56% of participants whose answers to the MMSE sentence were excluded from the analyses had cognitive impairment compared to 13.86% among those whose answers were included. The excluded participants were older and less educated. Women and those older than 80 years had the lowest scores in the MMSE. There was no statistically significant relationship between gender, age, schooling, and textual performance. There was a modest but significant correlation between number of words written and the scores in the Language subdomain. Conclusions: Results suggest the strong influence of schooling and age over MMSE sentence performance. Failing to write a sentence may suggest cognitive impairment, yet, instructions for the MMSE sentence, i.e. to produce a simple sentence, may limit its clinical interpretation.

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INTRODUCTION: Schizophrenia is a chronic mental disorder associated with impairment in social functioning. The most widely used scale to measure social functioning is the GAF (Global Assessment of Functioning), but it has the disadvantage of measuring at the same time symptoms and functioning, as described in its anchors. OBJECTIVES:Translation and cultural adaptation of the PSP, proposing a final version in Portuguese for use in Brazil. METHODS: We performed five steps: 1) translation; 2) back translation; 3) formal assessment of semantic equivalence; 4) debriefing; 5) analysis by experts. Interrater reliability (Intraclass correlation, ICC) between two raters was also measured. RESULTS: The final version was applied by two independent investigators in 18 adults with schizophrenia (DSM-IV-TR). The interrater reliability (ICC) was 0.812 (p < 0.001). CONCLUSION: The translation and adaptation of the PSP had an adequate level of semantic equivalence between the Portuguese version and the original English version. There were no difficulties related to understanding the content expressed in the translated texts and terms. Its application was easy and it showed a good interrater reliability. The PSP is a valid instrument for the measurement of personal and social functioning in schizophrenia.

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Microcredit, a small lending system, invests on an individual's creativity by stimulating the development of their own potential. This process leads to the attainment of various objectives which in turn allow individuals to develop their skill awareness. Consequently, this process also increases an individual’s self-esteem and self-confidence. These factors play an important role in the aetiology of a number of mental disorders. Namely, those characterized by a series of psychological conditions which impede the full development of a person’s personal, relational and social sphere. Furthermore, since Microcredit is thought to produce tangible goods, such as income, and intangible goods, such as self-esteem and mutual trust, it could also represent an innovative socio-economic tool. We therefore also hypothesize that, Microcredit would be valuable in maximizing abilities/skills in those subjects who are financially excluded and rarely perceived as a ‘resource’ for the Community The longitudinal study set the impact of the Grameen Bank microcredit program on new borrowers women from Noakhali District at the south Bangladesh. The impact evaluation assessment has been structured to detect individual, family and social changes. Manova Analysis allowed distinguishing from women with positive or negative outcomes related to the loan performance. Data revealed consistent differences in terms of economical outcomes and psychological well being amongst the groups of subject analyzed. The data gathered in relation to the changes arisen in the individuals should be looked into through future, continuous and systematic, monitoring.

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The monitoring of cognitive functions aims at gaining information about the current cognitive state of the user by decoding brain signals. In recent years, this approach allowed to acquire valuable information about the cognitive aspects regarding the interaction of humans with external world. From this consideration, researchers started to consider passive application of brain–computer interface (BCI) in order to provide a novel input modality for technical systems solely based on brain activity. The objective of this thesis is to demonstrate how the passive Brain Computer Interfaces (BCIs) applications can be used to assess the mental states of the users, in order to improve the human machine interaction. Two main studies has been proposed. The first one allows to investigate whatever the Event Related Potentials (ERPs) morphological variations can be used to predict the users’ mental states (e.g. attentional resources, mental workload) during different reactive BCI tasks (e.g. P300-based BCIs), and if these information can predict the subjects’ performance in performing the tasks. In the second study, a passive BCI system able to online estimate the mental workload of the user by relying on the combination of the EEG and the ECG biosignals has been proposed. The latter study has been performed by simulating an operative scenario, in which the occurrence of errors or lack of performance could have significant consequences. The results showed that the proposed system is able to estimate online the mental workload of the subjects discriminating three different difficulty level of the tasks ensuring a high reliability.

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Most people intuitively understand what it means to “hear a tune in your head.” Converging evidence now indicates that auditory cortical areas can be recruited even in the absence of sound and that this corresponds to the phenomenological experience of imagining music. We discuss these findings as well as some methodological challenges. We also consider the role of core versus belt areas in musical imagery, the relation between auditory and motor systems during imagery of music performance, and practical implications of this research.

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Active head turns to the left and right have recently been shown to influence numerical cognition by shifting attention along the mental number line. In the present study, we found that passive whole-body motion influences numerical cognition. In a random-number generation task (Experiment 1), leftward and downward displacement of participants facilitated small number generation, whereas rightward and upward displacement facilitated the generation of large numbers. Influences of leftward and rightward motion were also found for the processing of auditorily presented numbers in a magnitude-judgment task (Experiment 2). Additionally, we investigated the reverse effect of the number-space association (Experiment 3). Participants were displaced leftward or rightward and asked to detect motion direction as fast as possible while small or large numbers were auditorily presented. When motion detection was difficult, leftward motion was detected faster when hearing small number and rightward motion when hearing large number. We provide new evidence that bottom-up vestibular activation is sufficient to interact with the higher-order spatial representation underlying numerical cognition. The results show that action planning or motor activity is not necessary to influence spatial attention. Moreover, our results suggest that self-motion perception and numerical cognition can mutually influence each other.

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Identifying a human body stimulus involves mentally rotating an embodied spatial representation of one's body (motoric embodiment) and projecting it onto the stimulus (spatial embodiment). Interactions between these two processes (spatial and motoric embodiment) may thus reveal cues about the underlying reference frames. The allocentric visual reference frame, and hence the perceived orientation of the body relative to gravity, was modulated using the York Tumbling Room, a fully furnished cubic room with strong directional cues that can be rotated around a participant's roll axis. Sixteen participants were seated upright (relative to gravity) in the Tumbling Room and made judgments about body and hand stimuli that were presented in the frontal plane at orientations of 0°, 90°, 180° (upside down), or 270° relative to them. Body stimuli have an intrinsic visual polarity relative to the environment whereas hands do not. Simultaneously the room was oriented 0°, 90°, 180° (upside down), or 270° relative to gravity resulting in sixteen combinations of orientations. Body stimuli were more accurately identified when room and body stimuli were aligned. However, such congruency did not facilitate identifying hand stimuli. We conclude that static allocentric visual cues can affect embodiment and hence performance in an egocentric mental transformation task. Reaction times to identify either hands or bodies showed no dependence on room orientation.

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Background Cardiopulmonary resuscitation (CPR) causes significant stress, which may cause deficiencies in attention and increase distractibility. This may lead to misjudgements of priorities and delays in CPR performance, which may further increase mental stress (vicious cycle). This study assessed the impact of a task-focusing strategy on perceived stress levels and performance during a simulated CPR scenario. Methods This prospective, randomized-controlled trial was conducted at the simulator-center of the University Hospital Basel, Switzerland. A total of 124 volunteer medical students were randomized to receive a 10 minute instruction to cope with stress by loudly posing two taskfocusing questions (“what is the patient’s condition?”, “what immediate action is needed?”) when feeling overwhelmed by stress (intervention group) or a control group. The primary outcome was the perceived levels of stress and feeling overwhelmed (stress/overload); secondary outcomes were hands-on time, time to start CPR and number of leadership statements. Results Participants in the intervention group reported significantly less stress/overload levels compared to the control group (mean difference: -0.6 (95%CI −1.3, -0.1), p=0.04). Higher stress/overload was associated with less hands-on time. Leadership statements did not differ between groups, but the number of leadership statements did relate to performance. Hands-on time was longer in the intervention- group, but the difference was not statistically different (difference 5.5 (95%CI −3.1, 14.2), p=0.2); there were no differences in time to start CPR (difference −1.4 (95%CI −8.4, 5.7), p=0.71). Conclusions A brief stress-coping strategy moderately decreased perceived stress without significantly affecting performance in a simulated CPR. Further studies should investigate more intense interventions for reducing stress.