Effects of vision and haptics on categorizing common objects

Most research on object recognition and categorization centers on vision. However, these phenomena are likely influenced by the commonly used modality of touch. The present study tested this notion by having participants explore three-dimensional objects using vision and haptics in naming and sorting tasks. Results showed greater difficulty naming (recognizing) and sorting (categorizing) objects haptically. For both conditions, error increased from the concrete attribute of size to the more abstract quality of predation, providing behavioral evidence for shared object representation in vision and haptics.     

Telling stories: The structure of adults' narratives

Abstract

Adults' narratives were analysed to study life-span changes in their structure. The narratives were collected from a group of adults in their 60s, 70s, and 80s. Four separate analyses were performed on the narratives' (1) hierarchical structure, (2) syntactic structure, (3) propositional content, and (4) cohesion. Age-group differences were obtained for the measures of hierarchical structure, syntactic structure, and cohesion. Further analyses revealed that the structural complexity of the narratives influenced their syntactic structure and cohesion. Interactions between the effects of age group and structural complexity suggest that elderly adults minimise the syntactic complexity of their narratives, reducing their cohesion, when producing structurally complex narratives. Finally, ratings of the quality of the narratives were strongly correlated with their structural complexity, suggesting that telling a “good” story involves constructing complex plots.     

Locomotor analysis of the taiep rat

Locomotor activity (tremor, ataxia, immobility, epilepsy, and paralysis) in the taiep rat, which suffers from a myelin deficient disorder, has not been previously documented. This study used walking track analysis of footprints to analyze locomotor activity in the taiep rat in comparison to normal, age-matched controls. The results confirmed differences between normal and taiep rats in terms of stride length, step length, and stride width. In addition, we found significant interactions between age and condition for stride and step length. The results suggest that locomotor analysis is a sensitive indicator of myelin deficiency. The results are discussed in terms of the underlying myelin deficiency and possible treatment regimens.     

Equipment malfunctions and attribution of causality

The purpose of this study was to test whether individuals would be more likely to attribute the cause for the malfunction of a new piece of equipment as a manufacturing problem in the equipment or as an inability on their part to properly work with the equipment. The subjects were 600 residents of Florida, selected by a stratified random sample and interviewed in a statewide telephone survey. Subjects were more likely to attribute the cause to themselves rather than the machine. Overall, 71% attributed the cause to themselves, while only 24% said the machine was at fault. There was also an interaction effect in terms of income, with middle-income users more likely to blame the machine and upper-income users more likely to blame themselves. Further, there was also a significant relationship between attribution of cause and age, with older respondents being more likely to attribute cause to themselves. These results imply that attribution may differ when the potential object of attribution is a machine rather than another person.     

The use of schematic knowledge about sources in source monitoring

Source monitoring refers to mental processes leading to attributions regarding the origin of information. We tested Johnson, Hashtroudi, and Lindsay's (1993) assumption that prior source-relevant knowledge is used in some source-monitoring tasks. In two experiments using different domains of schematic knowledge, two sources presented information that was expected for one source and somewhat unexpected for the other. In a later source-monitoring test, participants decided whether items had been presented by Source A, by Source B, or were new. The results of both experiments show that source identification is better for expected items than for somewhat unexpected items. Multinomial modeling analyses revealed that when participants do not remember the source of information, they guess that it was presented by the expected source. These results provide evidence for the claim that source monitoring can be based on prior knowledge and support a guessing hypothesis.     

Chronically increased Gsalpha signaling disrupts associative and spatial learning

The cAMP/PKA pathway plays a critical role in learning and memory systems in animals ranging from mice to Drosophila to Aplysia. Studies of olfactory learning in Drosophila suggest that altered expression of either positive or negative regulators of the cAMP/PKA signaling pathway beyond a certain optimum range may be deleterious. Here we provide genetic evidence of the behavioral and physiological effects of increased signaling through the cAMP/PKA pathway in mice. We have generated transgenic mice in which the expression of a constitutively active form of Gsalpha (Gsalpha* Q227L), the G protein that stimulates adenylyl cyclase activity, is driven in neurons within the forebrain by the promoter from the CaMKIIalpha gene. Despite significantly increased adenylyl cyclase activity, Gsalpha* transgenic mice exhibit PKA-dependent decreases in levels of cAMP due to a compensatory up-regulation in phosphodiesterase activity. Interestingly, Gsalpha* transgenic mice also exhibit enhanced basal synaptic transmission. Consistent with a role for the cAMP/PKA pathway in learning and memory, Gsalpha* transgenic mice show impairments in spatial learning in the Morris water maze and in contextual and cued fear conditioning tasks. The learning deficits observed in these transgenic mice suggest that associative and spatial learning requires regulated Gsalpha protein signaling, much as does olfactory learning in Drosophila.     

Effects of counseling Ashkenazi Jewish women about breast cancer risk

The goal of this study was to determine whether genetic counseling or psychosocial group counseling provided to Ashkenazi women can reduce breast cancer worry, cancer risk perception, and interest in having genetic testing. Women (N=211) were randomized to receive individual genetic risk counseling, to receive a group psychosocial group counseling, or to serve as a control group. The authors found that both counseling methods reduced cancer worry, lowered perceptions of breast cancer risk, and decreased interest in having genetic testing. Counseling can help women gain a more accurate perception of their risk, expose them to the benefits and limitations of genetic testing, and reduce their worry about cancer.