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91.
This study broaches in a novel way the analysis of cognitive impairment characteristic of the early stages of Alzheimer's Disease (AD). Specifically, we attempt to determine the acoustic speech parameters that are sensitive to the onset of the disease, and their association with the language deficit characteristic of AD. Speech analysis was carried out on 21 elderly patients with AD using Praat software, which analyzes the acoustic components of speech. The data obtained were subjected to stepwise regression, using the overall scores obtained in the test as the criterion variable, and the scores on the frequency, amplitude and periodicity variables as predictors of performance. We found that the percentage of voiceless segments explains a significant portion of the variance in the overall scores obtained in the neuropsychological test. This component seems to be related mainly to the patient's ability in phonological fluency. This finding could permit the creation of a diagnostic test for AD through analysis of the acoustic speech parameters at very low cost in terms of both time and resources.  相似文献   
92.
This study used depression (CDI - Kovacs, 1981), anxiety (MASC - March, 1997) and coping strategy (CRI-Y - Moos, 1993) scales and studied the fitness and discriminant validity of reduced versions. The sample consisted of 916 Portuguese pupils, 54.3% feminine, aged 10 to 21 years old. The participants were selected from a set of public schools nation-wide. Two classes were chosen from the 5th to the 12th grades. A set of principal component analyses was carried out in a randomly chosen sample (n = 394) and all the three reduced measures were found to be strongly correlated with the previous. Confirmatory factor analyses (CFA) using the other part of the sample (n = 522) revealed adjustment indexes suggesting a good fit for both the whole model and gender and age groups separately. All scales revealed a good internal consistency. Globally, girls were more anxious and developed more coping strategies than boys. Older students tended to be less depressed, while younger adolescents present higher scores in depression and anxiety and less coping strategies. Reduced scales are sensitive to gender and age differences and can be used in school settings in order to establish a baseline and roadmaps for both universal and selective mental health school based programs.  相似文献   
93.
This study analyzes the prevalence and characteristics of childhood and adolescence sexual abuse suffered by a sample of university students, as well as the variables associated with the nature of abuse. Participants anonymously completed the Questionnaire on Child Sexual Abuse, in order to obtain information about experience of sexual abuse. Of a total of 2,375 students, 289 (12.2%) declared having suffered sexual abuse before the age of 18. The invasiveness, continuity, and severity of abuse was related to the location where the abuse took place (the more severe cases were committed in the homes of the victim and perpetrator) and to the circumstances of abuse (relationships with partners/at a party or while caring for a child predicted more severe abuse). The age of the victim (preschool) and an intrafamilial relationship between victim and perpetrator were also related to more invasive, continuous, and severe sexual abuse. The knowledge of characteristics of perpetrator and victim and the context in which sexual abuse occurs can help to better comprehend the nature and correlates of sexual abuse. The results of the present study may contribute to the design of programs for the prevention of sexual abuse to minors.  相似文献   
94.
Accumulating evidence suggests that evening-type adolescents are exposed to a number of determinants that might have a negative impact on their health condition. Given that few studies have investigated the association between chronotype and quality of life measures in large samples of adolescents, the aim of this study was to assess the relationship between morningness-eveningness and health-related quality of life among 1600 adolescents (aged 12-16 years). Adolescents completed the Ve?u et Santé Per?ue de L'adolescent (VSP-A) and the Morningness-Eveningness Scale for Children (MESC). Girls and older adolescents reported worse health indicators and were more evening oriented. Evening-type adolescents obtained lower scores on vitality, physical and psychological well-being, body image, relations with parents, relations with teachers, school work and global health scale.  相似文献   
95.
The aim of this study was to analyse the screening utility of the Social Anxiety Screening Scale (SASS/EDAS) in a sample of 227 adolescents with social anxiety disorder and 156 Without it (14-17 years). Results showed that the EDAS subscales (Avoidance, Distress and Interference) scores were reliable in terms of internal consistency (alpha > .80). All the subscales discriminated between adolescents with and without the disorder. They also showed a positive and significant correlation with other empirically validated measures of social anxiety. The three subscales indicated relevant sensitivity (69.16-84.14%), specificity (63.46-66.03%) and areas under the curve (.74-.81%). Binary logistic regression analyses indicated the adequate predictive utility of EDAS subscales, with the Distress subscale as the best diagnostic predictor. The data provide empirical evidence of the usefulness of EDAS as a screener for adolescent social anxiety disorder in terms of reliability, convergent and discriminant validity, diagnostic accuracy and clinical usefulness.  相似文献   
96.
This study investigated prospective links between quality of the early caregiving environment and children's subsequent executive functioning (EF). Sixty-two families were met on five occasions, allowing for assessment of maternal interactive behavior, paternal interactive behavior, and child attachment security between 1 and 2 years of age, and child EF at 2 and 3 years. The results suggested that composite scores of parental behavior and child attachment were related to child performance on EF tasks entailing strong working memory and cognitive flexibility components (conflict-EF). In particular, child attachment security was related to conflict-EF performance at 3 years above and beyond what was explained by a combination of all other social antecedents of child EF identified thus far: child verbal ability and prior EF, family SES, and parenting behavior. Attachment security may thus play a meaningful role in young children's development of executive control.  相似文献   
97.
Brain event-related potentials are a useful tool for investigating visual processing and action planning. This technique requires extremely accurate synchronization of stimulus delivery with recordings. The precision of the onset time of visual stimulus delivery is a major challenge when attempting to use real, three-dimensional objects as stimuli. Here, we present an innovative device, the “box for interaction with objects” (BIO), that is designed to synchronize the presentation of objects with electroencephalographic (EEG) recordings. To reach the required resolution of stimulus-onset timing, the BIO system features an interface with reflective glass and light-emitting diodes (LEDs). When the LEDs inside the BIO are turned on, the object inside becomes visible, and a synchronizing pulse is sent to the recording systems. The BIO was tested in a motivational study that focused on visual and motor event-related potentials. EEG signals were recorded during the presentation of an emotion-laden object that could be grasped and brought close to the participant’s chest. BIO successfully synchronized the appearance of a three-dimensional object with EEG recordings, which would allow for an analysis of visual and motor event-related potentials in the same experiment. The BIO device, through a high-quality psychophysiological approach, offers a new perspective for the study of the motivational factors that drive actions toward relevant stimuli.  相似文献   
98.
This experiment investigated social referencing as a form of discriminative learning in which maternal facial expressions signaled the consequences of the infant's behavior in an ambiguous context. Eleven 4- and 5-month-old infants and their mothers participated in a discrimination-training procedure using an ABAB design. Different consequences followed infants' reaching toward an unfamiliar object depending on the particular maternal facial expression. During the training phases, a joyful facial expression signaled positive reinforcement for the infant reaching for an ambiguous object, whereas a fearful expression signaled aversive stimulation for the same response. Baseline and extinction conditions were implemented as controls. Mothers' expressions acquired control over infants' approach behavior for all participants. All participants ceased to show discriminated responding during the extinction phase. The results suggest that 4- and 5-month-old infants can learn social referencing via discrimination training.  相似文献   
99.
We studied the acquisition of the ordinal meaning of number words and examined its development relative to the acquisition of the cardinal meaning. Three groups of 3-, 4-, and 5-year-old children were tested in two tasks requiring the use of number words in both cardinal and ordinal contexts. Understanding of the counting principles was also measured by asking the children to assess the correctness of a cartoon character's counting in both contexts. In general, the children performed cardinal tasks significantly better than ordinal ones. Tasks requiring the production of the number for a given quantity or position were solved more accurately than those testing the ability to select a set of n objects or the object in the nth position. Different profiles were obtained for the principles; those principles shared by the two contexts were mastered earlier in the cardinal context. Regarding order (ir)relevance, older children adhered to rigid ways of counting, producing better results in the ordinal context and incorrect rejections in the cardinal trials. Altogether, our data indicate that the acquisitions of cardinal and ordinal meanings of numbers are related, and cardinality precedes the development of ordinality.  相似文献   
100.
Researchers often use very abbreviated (e.g., 1-item, 2-item) measures of personality traits due to their convenience and ease of use as well as the belief that such measures can adequately capture an individual's personality. Using data from 2 samples (N = 437 employees, N = 355 college students), we show that this practice, particularly the use of single-item measures, can lead researchers to substantially underestimate the role that personality traits play in influencing important behaviors and thereby overestimate the role played by new constructs. That is, the use of very short measures of personality may substantially increase both the Type 1 and Type 2 error rates. We argue that even slightly longer measures can substantially increase the validity of research findings without significant inconvenience to the researcher or research participants.  相似文献   
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