Biomedical subjects

J A Groeger

Publications and source records attributed to J A Groeger.

6 recordsLinked to original sources

PubMed2006

Youthfulness, inexperience, and sleep loss: the problems young drivers face and those they pose for us.

Young inexperienced drivers are more likely to be involved in road traffic crashes than drivers who are older and more experienced. This paper argues that neither age nor inexperience are, in and of themselves, sufficient explanations of the association between age, experience, and casualty rates. The aim here is to consider what it is about inexperienced young drivers in particular that may increase crash risk. Evidence is reviewed showing differential sleep loss among different teenage groups, which may relate to recently presented evidence that young teenagers are more crash involved than drivers in their early twenties. Potential acute and chronic effects of sleep loss among teenagers and young adults are described.

Accidents, Traffic↗

PubMed2006

Attention-memory interactions in scene perception.

The perception of natural scenes relies on the integration of pre-existing knowledge with the immediate results of attentional processing, and what can be remembered from a scene depends in turn on how that scene is perceived and understood. However, there are conflicting results in the literature as to whether people are more likely to remember those objects that are consistent with the scene or those that are not. Moreover, whether any discrepancy between the likelihood of remembering schema-consistent or schema-inconsistent objects should be attributed to the schematic effects on attention or on memory remains unclear. To address this issue, the current study attempted to directly manipulate attention allocation by requiring participants to look at (i) schema-consistent objects, (ii) schema-inconsistent objects, or (iii) to share attention equally across both. Regardless of the differential allocation of attention or object fixation, schema-consistent objects were better recalled whereas recognition was independent of schema-consistency, but depended on task instruction. These results suggest that attention is important both for remembering low-level object properties, and information whose retrieval is not supported by the currently active schema. Specific knowledge of the scenes being viewed can result in the recall of non-fixated objects, but without such knowledge attention is required to encode sufficient detail for subsequent recognition. Our results demonstrate therefore that attention is not critical for the retrieval of objects that are consistent with a scene's schematic content.

Attention↗

PubMed2004

Sleep quantity, sleep difficulties and their perceived consequences in a representative sample of some 2000 British adults.

Sleep problems and sleep restriction are popular topics of discussion, but few representative data are available. We document Britain's sleep based on a nationally representative sample of 1997, 16-93 year olds, who participated in face-to-face interviews. Fifty-eight per cent of respondents reported sleep problems on one or more nights the previous week and 18% reported that the sleep they obtained was insufficient on the majority of nights. Sleep durations were longest in the youngest participants (16-24 years), who slept on average 1 h longer than the 7.04 (SD 1.55) sample average. Sleep duration showed no appreciable change beyond middle age. Men and women reported sleeping similar amounts but women reported more sleep problems. Men reported sleeping less when there were more children in their household. Workers (i.e. employees) reported sleeping less on workdays than on non-workdays, but those based at home and those not employed did not. Inability to switch off from work was related to sleep duration on non-workdays. Across all participants average sleep duration exhibited a non-monotonic association with quality of life (i.e. contribution of sleep to energy, satisfaction and success in work, home and leisure activities). Quality of life was positively associated with sleep duration, for durations up to 9 h, but negatively associated with quality of life beyond this. Comparison of our data with the US national sleep poll revealed that Britain sleeps as little or less, whereas a comparison with data reported 40 years ago revealed no statistically reliable reductions. Although we may not sleep less than four decades ago, when we report sleeping less we also tend to associate that lack of sleep with poor performance and quality of life.

Adolescent↗

PubMed2003

Working-memory and auditory localization: demand for central resources impairs performance.

Four experiments explored possible roles for working memory in sound localization. In each experiment, the angular error of localization was assessed when performed alone, or concurrently with a working-memory task. The role of the phonological slave systems in auditory localization was ruled out by Experiments 1 and 2, while an engagement of central resources was suggested by the results of Experiment 3. Experiment 4 examined the involvement of visuo-spatial systems in auditory localization and revealed impairment of localization by the concurrent spatial working-memory task. A comparison of dual-task decrement across all four studies suggests that localization places greater demand on central than on spatial resources.

Adult↗

PubMed1989

Assessing one's own and others' driving ability: influences of sex, age, and experience.

Observational studies of drivers' involvements in dangerous situations suggest that young males drive differently from other road users. Studies of drivers' assessments of their own ability appear to show that they believe they drive better than their peers and that, while young males equate their ability with that of older male drivers, the latter group see themselves as superior to their younger counterparts but of equivalent ability to peers. It is unclear from previous studies what the influence of driving experience is on such assessments and, indeed, what female drivers feel about their ability. The present studies suggest that the widely reported tendency for people to overestimate their ability may be largely artifactual, that males and females describe their performance similarly, and that previously reported age differences disappear when driving experience is controlled. Among the differences that remain is the reported greater "recklessness" and comparative lack of "smoothness" of young males' driving. The implications of these findings for our understanding of risk assessment and acceptance are discussed.

Adult↗

PubMed1984

Evidence of unconscious semantic processing from a forced error situation.

A study was carried out to determine whether subjects extracted information from words presented below their recognition and awareness thresholds. A series of target words was used to generate the word matrix, which was a set of 24 words related to the target in specified ways. Following subthreshold exposure of a target word, subjects chose the word they thought had been shown from the word matrix for that particular target. It was held that the alternative chosen was a function of the type of processing the target was receiving. Results showed that structural analysis of the target predominated below recognition threshold, whereas semantic analysis predominated below awareness threshold.

Adolescent↗