The sounds of dominance.

A study was conducted to determine the effects of vocal cues on judgements of dominance in an interpersonal influence context. Physical measures of human vocal cues and participant ratings of dominance were obtained from videotapes of actors delivering short influence messages. After controlling for linguistic and visual content of messages, results indicated that mean amplitude and amplitude standard deviation were positively associated with dominance judgments, whereas speech rate was negatively associated with dominance judgments. An unexpected interaction revealed that mean fundamental frequency (F₀) was positively associated with dominance judgments for male speakers but not significantly associated with dominance judgments for female speakers. F₀ standard deviation was not significantly associated with dominance judgments. Results support the conclusion that dominance judgments are inferred from multiple sources of information and that some vocal markers of dominance are more influential than others.     

Differentiating insight from non-insight problems

This study aimed to investigate whether a range of tasks that have been generally classed as requiring insight form an empirically separable group of tasks distinct from tasks generally classed as non-insight. In this study, 24 insight tasks, 10 non-insight tasks, and tests of individual differences in cognitive abilities and working memory were administered to 60 participants. Cluster analysis of the problem-solving tasks indicated that the presumed insight problems did tend to cluster with other presumed insight problems, and similarly the presumed non-insight problems tended to cluster with other presumed non-insight tasks. Performance on presumed insight problems was particularly linked to measures of ideational flexibility with a different pattern of results for the non-insight tasks. Spatial insight problems were linked to spatial flexibility and verbal insight tasks were linked to vocabulary scores. The results are discussed in relation to recent developments of dual process theories of thinking.     

The development of explicit memory for basic perceptual features

In three experiments with 164 individuals between 4 and 80 years old, we examined age-related changes in explicit memory for three perceptual features--item identity, color, and location. In Experiments 1-2, feature recognition was assessed in an incidental learning, gamelike task resembling the game Concentration. In Experiment 3, feature recognition was assessed using a pencil-and-paper task after intentional learning instructions. The form of the explicit memory function across the life span varied with the particular perceptual feature tested and the type of task. Item recognition was excellent at all ages but was significantly poorer for older adults than children, color recognition peaked in late childhood on the gamelike task, and location recognition peaked in early adulthood on the pencil-and-paper task. These findings indicate that performance on explicit memory tests is not a consistent inverted U-shaped function of age across various features. Explicit memory performance depends on what is measured and how. Because explicit memory typically reflects a composite of different features, age-related changes in explicit memory will not necessarily correspond to the function for any single one.