Body image perceptions among Chinese children and adolescents

In order to investigate the body image self-perception and the prevalence of body dissatisfaction among Chinese children and adolescents, 9100 children aged 3-15 years living in four cities completed a questionnaire assessing body image self-percepts and ideals by figural stimuli. The results indicate that (1) children's body ratings started to be significantly related to their BMIs at age 5 and correlations increased with age; (2) a wide range of current body sizes was chosen by Chinese boys and girls; (3) the ideal body sizes of boys and girls selected by boys and girls, respectively, were "boys by boys">"boys by girls">"girls by boys">"girls by girls" and (4) the satisfaction, mild dissatisfaction, and moderate dissatisfaction rates were 40.1%, 36.4% and 23.5%, respectively. Differences as a function of gender and age were identified. It was concluded that the prevalence of body dissatisfaction among children and adolescents of urban China was striking, and that the Chinese boys were not immune to body dissatisfaction.     

Directed forgetting in working memory: age-related differences

This study explored the effects of ageing on working memory by means of the directed forgetting procedure designed by Reed (1970). Memory for a letter trigram was compared in conditions where it was either presented alone (single-item), or followed by a second trigram to be recalled (interference), or followed by a second trigram to be forgotten (directed forgetting). The results clearly indicated that elderly participants inhibited the no-longer-relevant information less efficiently (recall in the single-item condition - recall in the directed forgetting condition), as predicted by the model of Hasher and Zacks (1988). However, the results also demonstrated that sensitivity to interference (recall in the single-item condition - recall in the interference condition) increased in the condition in which no inhibition was directly required.     

Spatial learning in rats is impaired by microinfusions of protein kinase C-gamma antisense oligodeoxynucleotide within the nucleus accumbens

The nucleus accumbens (NAcc) has been shown to play a role in motor and spatial learning. Protein kinase C (PKC) has been implicated in the mechanisms of initiation and maintenance of long-term potentiation that is thought to be involved in the storage of long-term memory. In the present study, the importance of de novo synthesis of PKC-gamma within the NAcc in the acquisition and retention of spatial discrimination learning was assessed using an antisense knockdown approach. Separate groups of Long-Evans rats were exposed to acute microinfusions (6microg/microl) of PKC-gamma antisense oligodeoxynucleotide (AS-ODN), control oligodeoxynucleotide (C-ODN) or vehicle into the NAcc at 24 and 3h before each training session. Behavioral findings showed that the blockade of NAcc-PKC-gamma translation caused impairments in the early phase of learning and retention of spatial information. Biochemical experiments showed that PKC-gamma expression was reduced and Ca(2+)/phospholipid-dependent protein kinase C (PKC) activity was blocked significantly in the AS-ODN-treated rats in comparison with control rats. The present findings suggest that NAcc-PKC-gamma plays a role during the early acquisition of spatial learning. Also, retention test results suggest that NAcc-PKC-gamma may be working as an intermediate factor involved in the onset of molecular mechanisms necessary for spatial memory consolidation within the NAcc.     

Acquisition, learning, or development of language? Skinner's "Verbal Behavior" revisited

In 1957, Skinner, in his "Verbal Behavior", proposed an explanation on how a language is learned. In 1959, Chomsky strongly argued the non-learnability of language, establishing in the field of developmental psycholinguistics the substitution of the term "learning" for that of "acquisition". Currently, the constructivist models describe language acquisition as a process of ontogenetic, gradual, complex, and adaptive change. This new theoretical framework has been especially useful for rereading Verbal Behavior because it facilitates recovering the Skinnerian learning mechanisms. This can be observed in the recent research trends that recapture reinforcement and imitation (echoic responses), although they are now located in the initial phases of the process and are included in a cognitive dynamic that, by gradually increasing its complexity, can achieve grammar. The new constructivist theoretical framework, by retrieving the functional and referential aspects of language, can also take advantage of the classic Skinnerian proposal about the pragmatic types of verbal behavior, providing it with new meaning.     

The language-specific nature of grammatical development: evidence from bilingual language learners

The fact that early lexical and grammatical acquisition are strongly correlated has been cited as evidence against the view that the language faculty is composed of dissociable and autonomous modules (Bates & Goodman, 1997). However, previous studies have not yet eliminated the possibility that lexical-grammar associations may be attributable to language-general individual differences (e.g. children who are good at learning words are good at learning grammar). Parent report assessments of toddlers who are simultaneously learning English and Spanish (n = 113) allow an examination of the specificity of lexical-grammar relationships while holding child factors constant. Within-language vocabulary-grammar associations were stronger than cross-language relationships, even after controlling for age, proportion of language exposure, general language skill and reporter bias. Similar patterns were found based on naturalistic language samples (n = 22), ruling out a methodological artifact. These results are consistent with the view that grammar learning is specifically tied to lexical progress in a given language and provide further support for strong lexical-grammatical continuity early in acquisition.     

Death anxiety and death obsession in Spanish students

This study examined the dimensional structure of Templer's Death Anxiety Scale and Abdel-Khalek's Death Obsession Scale. The responses of 289 Spanish students to the Spanish forms of both scales were evaluated by means of a principal components analysis with varimax rotation. Three significant factors were identified: Death Obsession, Cognitive-Affective, and Death Anxiety. The distribution of the factor loadings for the items of both scales on Factors 1 and 3 supported the discriminant validity of the constructs specific to each of the scales, while Factor 2 showed a common component in both scales characterized by cognitive and affective aspects in relation to the idea of death.     

Iberian rock lizards (Lacerta monticola) assess short-term changes in predation risk level when deciding refuge use

Prey might assess that risk level estimated in the first encounter with a predator was fixed in subsequent responses, whereas prey using flexible behavior would track short-term changes in risk. The authors examined, in the field, refuge use of Iberian rock lizards (Lacerta monticola) after simulated predator attacks and tested (a) how risk was assessed when multiple sources of risk were present simultaneously, (b) how short-term changes in risk level of successive attacks affected refuge use, and (c) whether the interval between attacks was important, insofar as attacks were considered to be coming from the same or different predators. Results suggest that lizards have a flexible estimate of risk that is based on multiple sources and flexibly dependent on previous estimates.     

An application of item response theory analysis to alcohol, cannabis, and cocaine criteria in DSM-IV

Item response theory (IRT) is supplanting classical test theory as the basis for measures development. This study demonstrated the utility of IRT for evaluating DSM-IV diagnostic criteria. Data on alcohol, cannabis, and cocaine symptoms from 372 adult clinical participants interviewed with the Composite International Diagnostic Interview--Expanded Substance Abuse Module (CIDI-SAM) were analyzed with Mplus (B. Muthen & L. Muthen, 1998) and MULTILOG (D. Thissen, 1991) software. Tolerance and legal problems criteria were dropped because of poor fit with a unidimensional model. Item response curves, test information curves, and testing of variously constrained models suggested that DSM-IV criteria in the CIDI-SAM discriminate between only impaired and less impaired cases and may not be useful to scale case severity. IRT can be used to study the construct validity of DSM-IV diagnoses and to identify diagnostic criteria with poor performance.     

Exploring the structure of Zuckerman's Sensation Seeking Scale, Form V in a Spanish sample

The psychometric properties of the original version of the Sensation Seeking Scale (Form V) were analyzed in a sample of 1,006 Spanish university students. The total sample was randomly split into two halves. Exploratory factor analyses were conducted on the calibration sample (n=504), whereas confirmatory factor analysis procedures were performed on the validation sample (n=502). As previous studies have suggested, exploratory factor structure indicated that several items load on a different factor or have loadings lower than .30. Those problems were surpassed when the best five items per factor were factor analyzed again. The confirmatory factor analyses showed that a 4-factor simple structure model gave a clearly imperfect fit. A model of 20 items (5 items per factor) gave a better fit, although with similar problems regarding the low reliabilities of the Experience Seeking and Boredom Susceptibility subscales. The need for improvement of the four-factor structure is discussed.     

Effects of suppressing neutral and obsession-like thoughts in normal subjects: beyond frequency

Recent cognitive-behavioral theories on obsessive-compulsive disorder (OCD) show that deliberate attempts to suppress intrusive and undesirable thoughts lie at the genesis of clinical obsessions. In this paper the results of an experimental study on the suppression of neutral and obsession-like thoughts in normal subjects are presented. Eighty-seven university students performed in three experimental periods: (1) base-line monitoring, (2) experimental instruction, and (3) monitoring. For each of these periods, the frequency of the occurrence of a "white bear" thought or a personally relevant intrusive thought was registered. Half of the subjects received instructions to suppress the target-thought in period 2, and the other half were instructed to only monitor the target-thought in each of the experimental periods. Several measures were also obtained before and after the experiment: annoyance caused by the intrusion, suppression effort, subjective success, and evaluative appraisals of the target-thought. The results showed neither immediate nor delayed frequency increases of the target thought. However, evidence was found that deliberate thought suppression efforts, regardless of their content, had greater negative consequences than did non suppression. These results are discussed in relation to the recent cognitive proposals about OCD.