Atypical Hemispheric Specialization in Intellectual Deficiency

In order to determine the relation between hemispheric specialization for language and intellectual deficiency, two groups of lower-IQ subjects were compared to normal-IQ controls on word-dichotic listening tasks. Two conditions in which stimuli differed by their level of phonological complexity were used. Normal controls showed the expected right-ear advantage in both conditions. Moreover, they showed a greater magnitude of ear difference on the condition requiring higher-order phonological processing. In the mentally deficient group, almost half the subjects exhibited a left-ear advantage and they showed no difference between the two conditions in terms of the magnitude of ear difference. These results point to the presence of atypical hemispheric specialization in mentally deficient subjects.     

II Sensory feedback influences on keytapping motor tasks

Subjects were trained to tap a key continuously at a specific rate, and with a specific amount of pressure (regularity task). Performance of this task was studied under conditions of: (a) decreased auditory feedback (masking noise through earphones), (b) decreased visual feedback (tapping hand screened from view), (c) vibration (vibrators applied to forearm in order to “mask” proprioceptive feedback), (d) digital block of tapping finger, and (e) combination of all four conditions. Significant changes in rate and intensity of tapping resulted under conditions of decreased auditory feedback, vibration, and the combined condition.

In the second part of the study, the effects of different delayed sensory events on keytapping were examined. The five conditions of delayed sensory feedback were: (a) delayed auditory feedback, (b) delayed visual feedback, (c) delayed tactile feedback, (d) the first three delayed sensory events presented simultaneously, and (e) condition (d) repeated with digital block of the tapping finger.

The conditions of delayed sensory feedback did not markedly alter performance of the regularity task. The same conditions of delayed sensory feedback did, however, produce highly significant changes in the performance of a more complex pattern task. All of these delay conditions produced parallel changes in the pattern task, namely increased intensity and decreased rate of tapping. The fact that the pattern task is more disturbed by delayed sensory feedback than the regularity task suggests that temporal complexity of the task is one determinant of the degree to which it will be disturbed by a delay in sensory feedback.     

Adult Parent–Child Relationships: Relationship Quality, Support, and Reciprocity

A partir du modèle de la solidarité intergénérationnelle de Bengston ( Bengston & Roberts, 1991 ), on a étudié, chez 265 femmes entre deux âges vivant en Allemagne, les interrelations entre leurs valeurs familiales, leur perception de qualité de la relation avec leurs parents, le soutien qu’elles disent leur apporter et recevoir de leur part, ainsi que leur appréhension de l’entraide entre les générations. On s’est aussi demandé si l’aide apporté aux parents et la réciprocité perçu étaient en rapport avec la charge que les filles ressentaient suite au soutien accordé. Les données des diverses rubriques, fournies par les sujets, ont été traitées avec des analyses de régression logistiques multiple et multinomiale. Les analyses ont débouché sur des liaisons positives entre les valeurs familiales, la qualité des relations et le soutien aux parents. La réciprocité perçue était reliée aux aides mutuelles entre les générations et un soutien déséquilibré avait des effets négatifs sur la qualité de la relation. La charge ressentie pouvait ­être prédite à partir de la réciprocité perçue et de l’importance de l’aide. Cependant, sont apparus des modèles corrélationnels spécifiques dépendant à la fois du type d’aide et du niveau d’importance relatif du père et de la mère. Les résultats sont discutés dans le contexte du sens de la réciprocité et des obligations familiales dans une culture occidentale. In accordance with Bengtson's model of intergenerational solidarity (e.g. Bengtson & Roberts, 1991 ), the interrelations between adult daughters’ family values, their perception of the relationship quality with their parents, the support they reported to give to and to receive from their parents, and their perception of reciprocity in intergenerational support exchange were investigated for N= 265 middle‐aged women in Germany. It was also asked whether the support given to parents and perceived reciprocity are related to daughters’ felt burden as a result of their support. Cross‐sectional, self‐report data were examined with multiple and multinomial logistic regression analyses. The analyses revealed positive relations between family values, relationship quality, and support to parents. Perceived reciprocity was associated with the exchange of intergenerational support, and imbalance in support had negative effects on the relationship quality. Felt burden was predicted by the extent of support and the perceived reciprocity. However, specific correlational patterns depending on the kind of support as well as differences in the importance of mother and father occurred. The findings are discussed against the background of the meaning of family obligations and reciprocity in a Western culture.     

The onset and mastery of spatial language in children acquiring British Sign Language

In the course of language development children must solve arbitrary form-to-meaning mappings, in which semantic components are encoded onto linguistic labels. Because sign languages describe motion and location of entities through iconic movements and placement of the hands in space, child signers may find spatial semantics-to-language mapping easier to learn than child speakers. This hypothesis was tested in two studies: a longitudinal analysis of a native signing child's use of British Sign Language to describe motion and location events between the ages 1–10 and 3–0, and performance of 18 native signing children between the ages of 3–0 and 4–11 on a motion and location sentence comprehension task. The results from both studies argue against a developmental advantage for sign language learners for the acquisition of motion and location forms. Early forms point towards gesture and embodied actions followed by protracted mastery of the use of signs in representational space. The understanding of relative spatial relations continues to be difficult, despite the iconicity of these forms in the language, beyond 5 years of age.     

Geographic vocal variation and perceptual discrimination abilities in male Australian sea lions

Vocal characteristics can vary among and within populations. In species with geographic variation in the structure of vocalizations, individuals may have the ability to discriminate between calls from local and non-local individuals. The ability to distinguish differences in acoustic signals is likely to have a significant influence on the outcome of social interactions between individuals, including potentially mate selection and breeding success. Pinnipeds (seals, fur seals, sea lions and walruses) are highly vocal yet the Australian sea lion (Neophoca cinerea) is the only eared seal known to show geographic vocal variation in male barks. Barks are produced in many social interactions and encode sufficient information for both individual and colony identity to be discriminable. Yet until now, whether males could themselves discriminate these bark differences was unclear. We performed playback experiments in four breeding colonies to investigate whether males can discriminate local from non-local barks. Overall, males responded more strongly to barks from their own colony compared to barks from other colonies regardless of whether those other colonies were close or distant. Competition for females is high in Australian sea lions, but mating periods are asynchronous across colonies. The ability to correctly assess whether a male is from the same colony, thus representing a potential competitor for mates, or merely a visitor from elsewhere, may influence how males interact with others. Given the high cost of fighting, the ability to discern competitors may influence the nature of male–male interactions and ultimately influence how they allocate reproductive effort.     

Maternal-Related Predictors of Self-Regulation Among Low-Income Youth

The association between self-regulation and various adaptive outcomes has become a topic of growing interest to researchers. Yet, there is not much research on predictors of self-regulation in children. Using a cross-sectional design and an array of psychometrically sound scales and measures from multiple informants, this study examined whether maternal characteristics, namely maternal mental health, substance abuse, parenting practices, and child monitoring predicted self-regulation in children. Participants included a culturally diverse group of 155 youths (ages 8–17) and their mothers, all of whom were part of a larger investigation of low-income families in a mid-sized Northeastern city in the United States. Results showed that maternal substance abuse, parenting practices and parental monitoring independently predicted children’s self-regulation, accounting for 23% of the variance. Additional analyses indicated that parenting practices may partly mediate the effect of maternal mental health on children’s self-regulation. Implications for intervention and practice, especially those aimed to mitigate the detrimental effects of maternal mental health problems on children’s self-regulation, are discussed. Further research, both longitudinal and experimental, is warranted in order to extend this line of investigation.     

Snakes, spiders, guns, and syringes: how specific are evolutionary constraints on the detection of threatening stimuli?

In three experiments, the efficiency in detecting fear-relevant and fear-irrelevant visual stimuli are compared. A visual search paradigm is used where participants are presented with matrices of different sizes (4 objects/9 objects) and must determine whether all objects are taken from the same category or whether there is a discrepant one. Results from all experiments were consistent with the threat-superiority effect. Participants were quicker when the target was threatening than when it was not. Other indicators confirmed that the detection of threatening targets involves more efficient processes (reduced slopes, absence of position effects). A crucial aspect of these experiments was the comparison of evolutionary-relevant (snakes, spiders, etc.) and modern (guns, syringes, etc.) threats. The threat-superiority effect was repeatedly found for both types of target. Stronger effects were sometimes observed for modern than for evolutionary-relevant threats. The implications for evolutionary explanations of the effect of fear on visual attention are discussed.