Behavioral lateralization during spontaneous smelling tasks

The smelling behavior of 52 right-handed subjects was videotaped during tasks involving identification and recognition of different odors. Analysis showed that men more often used the right nostril than the left whatever the odor. There was no significant difference for the women. These results support a more marked cerebral asymmetry in men than in women and a main involvement of the right cerebral hemisphere in the olfactory processes at least by right-handed men.     

Conditioned and unconditioned fear organized in the periaqueductal gray are differentially sensitive to injections of muscimol into amygdaloid nuclei

The lateral and basolateral nuclei of the amygdala (LaA and BLA, respectively) serve as a filter for unconditioned and conditioned aversive information that ascends to higher structures from the brainstem, whereas the central nucleus of the amygdala (CeA) is considered to be the main output for the defense reaction. It has been shown that the dorsal periaqueductal gray (dPAG) is activated by threatening stimuli and has important functional links with the amygdala through two-way anatomical connections. In this work, we examined the influence of chemical inactivation of these nuclei of amygdala on the freezing and escape responses induced by electrical stimulation through electrodes implanted in the dPAG of Wistar rats. Each rat also bore a cannula implanted in the LaA, BLA or CeA for injections of muscimol (0.5 microg/0.5 microL) or its vehicle. The duration of freezing behavior that outlasts electrical stimulation of the dPAG was also measured. On the following day, these animals were submitted to a contextual fear-conditioning using foot shocks as unconditioned stimulus. Conditioned freezing to contextual cues previously associated with foot shocks was also inhibited by injections of muscimol into these amygdaloid nuclei. The contextual conditioned freezing behavior is generated in the neural circuits of conditioned fear in the amygdala. The data obtained also show that injections of muscimol into the three amygdaloid nuclei did not change the aversive threshold of freezing, but disrupted the dPAG post-stimulation freezing. Previous findings that the latter freezing results directly from dPAG stimulation and that it is not sensitive to a context shift suggest that it is unconditioned in nature. Thus, the amygdala can affect some, but not all, aspects of unconditioned freezing. Post-stimulation freezing may reflect the process of transferring aversive information from dPAG to higher brain structures.     

Length effect in reading and lexical decision: evidence from skilled readers and a developmental dyslexic participant

A number of experimental data have shown that naming latency increases with length for pseudo-words but not for frequent real words. Different interpretations have been proposed by current models of reading to account for such a length effect. The aim of the present study was to assess the impact of lexicality on length effect in both the reading and lexical decision tasks. For this purpose, skilled readers were asked to either name or make a lexical decision on words and pseudo-words differing in length from one to three syllables. Skilled readers' results show that length effect is modulated by lexicality in the reading task but no length effect was found in the lexical decision task. The tasks were further proposed to a well-compensated dyslexic participant who exhibited a visual attentional disorder in the absence of any associated phonological problems. A length effect on RTs was found for both words and pseudo-words in lexical decision but naming latencies were affected by length for the pseudo-words only. The present results largely conform to the predictions of the ACV98 model of reading. They are not compatible with the PDP models of reading and can only be partially accounted for by dual route models.     

False memories: young and older adults think of semantic associates at the same rate, but young adults are more successful at source monitoring

Two experiments explored whether the higher vulnerability to false memories in the DRM (J. Deese, 1959; H. L. Roediger & K. B. McDermott, 1995) paradigm in older compared to young adults reflects a deficit in source monitoring. In both experiments, adding together the number of falsely recalled critical lures and the number of critical lures produced on a post-recall test asking participants to report items that they had thought of but did not recall, indicated that the critical lures were activated during the experiment equally often in young and older adults. However, older adults were more likely than young adults to say that they had actually heard the lures. When strongly encouraged to examine the origin of memories (Experiment 2), the warning substantially reduced false recall in young but not older adults. These results are consistent with the idea that older adults have more difficulty later identifying the source of information that was activated as a consequence of intact semantic activation processes.     

Recognising the usual orientation of one's own face: the role of asymmetrically located details

Our ability to recognise the usual horizontal orientation of our own face (mirror orientation) as compared with another very familiar face (normal orientation) was examined in experiment 1. Participants did not use the same kind of information in determining the orientation of their own face as in determining the orientation of the other familiar face. The proportion of participants who reported having based their judgment on the location of an asymmetric feature (eg a mole) was higher when determining the orientation of their own face than when determining that of the other familiar face. In experiment 2, participants were presented with pairs of manipulated images of their own face and of another familiar face showing conflicting asymmetric features and configural information. Each pair consisted of one picture showing asymmetric features of a given face in a mirror-reversed position, while the facial configuration was left unchanged; and one picture in which the location of the asymmetric features was left unchanged, while the facial configuration was mirror-reversed. As expected from the hypothesis that asymmetric local features are more frequently used for the judgment of one's own face, participants chose the picture showing mirror-reversed asymmetric features when determining the usual orientation of their own face significantly more often than they chose the picture showing normally oriented asymmetric features when determining the orientation of the other face. These results are explained in terms of competing forward and mirror-reversed representations of one's own face.     

Impact of situational legitimacy and assertiveness-related anxiety/discomfort on motivation and ability to generate effective criticism responses

This study compares the motivation and the quality of criticism responses of 697 undergraduates who were divided into three levels of situation legitimacy (high, moderate, and low) and two levels (top versus bottom 40 percent) of anxiety related to previous generalized assertiveness behaviours. The impact of gender was also studied. The results showed the legitimacy of the situation for a critical response (preassessed with peer hold-out groups) significantly affected participants' motivation to criticize as well as the quality of their critical responses, notwithstanding the poor quality of all criticism responses. Anxiety related to previous global assertiveness was related to high motivation but not to quality of criticism responses. There were no gender effects. Results are interpreted within an avoidance learning paradigm wherein the connotative meaning of criticism is incongruent with harmonious long-term relationships so that it is suppressed until virtually forced by the specifics of highly legitimate situations.     

Six Years in the Cognitive and Metacognitive Life of 71 Families

Seventy-one families from a low socio-economic background, each with a son at risk of developing psychosocial problems at the onset of the study, were observed three times over a six-year period while solving a combinatorial task presented on a microcomputer. The permutations task was used to gather information with regard to cognitive functioning and cognitive self-regulation of the families, which were observed as a developmental unit. Cognitive functioning was assessed according to three variables: cognitive strategies, performance, and completion of the task. Six self-regulatory activities were assessed: task definition, planning, supervision, evaluation, parental support, and sharing of responsibilities. Although inefficient strategies were mainly used across the six years, the cognitive level of functioning improved over the years. Cognitive self-regulatory activities most often used across time were supervision and parental support. Differences were observed in the three time periods for supervision, task definition, parental support, and individual involvement. Results indicated a link between cognitive strategies used by the families to solve the task and their self-regulatory activities. Results are interpreted within both the Piagetian and Vygotskian perspectives. Families' cognitive self-regulatory activities observed in this study are an example of parental disengagement and children's growing involvement in a joint activity.     

Use of the Hereford Parent Attitude Survey as an outcome measure in parent education research

Research on outcome evaluation published since 1980 on the Hereford Parent Attitude Survey was reviewed in terms of sample size, type of parent training program used, and the scales' sensitivity to change in parental attitudes after intervention. Some support for the sensitivity of the Hereford was found, and, as an evaluation device to assess whether program goals have been achieved, the scale proved to be a useful instrument. The Hereford scale can be applied with reasonable confidence in research on parenting and in strategies to enhance effective parenting.