Biomedical subjects

Walter J Perrig

Publications and source records attributed to Walter J Perrig.

5 recordsLinked to original sources

PubMed2006

The influence of intention on masked priming: a study with semantic classification of words.

Unconscious perception is commonly described as a phenomenon that is not under intentional control and relies on automatic processes. We challenge this view by arguing that some automatic processes may indeed be under intentional control, which is implemented in task-sets that define how the task is to be performed. In consequence, those prime attributes that are relevant to the task will be most effective. To investigate this hypothesis, we used a paradigm which has been shown to yield reliable short-lived priming in tasks based on semantic classification of words. This type of study uses fast, well practised classification responses, whereby responses to targets are much less accurate if prime and target belong to a different category than if they belong to the same category. In three experiments, we investigated whether the intention to classify the same words with respect to different semantic categories had a differential effect on priming. The results suggest that this was indeed the case: Priming varied with the task in all experiments. However, although participants reported not seeing the primes, they were able to classify the primes better than chance using the classification task they had used before with the targets. When a lexical task was used for discrimination in experiment 4, masked primes could however not be discriminated. Also, priming was as pronounced when the primes were visible as when they were invisible. The pattern of results suggests that participants had intentional control on prime processing, even if they reported not seeing the primes.

Decision Making↗

PubMed2006

Decomposing intuitive components in a conceptual problem solving task.

Research into intuitive problem solving has shown that objective closeness of participants' hypotheses were closer to the accurate solution than their subjective ratings of closeness. After separating conceptually intuitive problem solving from the solutions of rational incremental tasks and of sudden insight tasks, we replicated this finding by using more precise measures in a conceptual problem-solving task. In a second study, we distinguished performance level, processing style, implicit knowledge and subjective feeling of closeness to the solution within the problem-solving task and examined the relationships of these different components with measures of intelligence and personality. Verbal intelligence correlated with performance level in problem solving, but not with processing style and implicit knowledge. Faith in intuition, openness to experience, and conscientiousness correlated with processing style, but not with implicit knowledge. These findings suggest that one needs to decompose processing style and intuitive components in problem solving to make predictions on effects of intelligence and personality measures.

Adult↗

PubMed2006

Retrieval experience in prospective memory: strategic monitoring and spontaneous retrieval.

According to the multi-process model of prospective memory (McDaniel & Einstein, 2000), performance in a prospective memory task may be due to spontaneous retrieval processes or due to strategic monitoring. Spontaneous retrieval is typically accompanied by a pop up experience and strategic monitoring by a search experience. In this study we report two experiments with young adults in which we systematically investigated whether retrieval experience differed across experimental conditions. In Experiment 1 some prospective memory targets were preceded by associated primes. We expected that presenting primes would enhance performance by an automatic activation of the intention and hence lead to an increase in pop up experiences. In Experiment 2 half of the participants received instructions containing information about the specific context in which the prospective memory task would occur, whereas the other half of the participants received no such information. We expected that specific context instructions would enhance performance by legitimate anticipation of the prospective memory task and hence would lead to an increase in search experiences. The results confirmed these expectations. They indicate that the assessment of retrieval experience can provide valuable insights into the processes underlying prospective memory performance. They also suggest that retrieval experience can vary systematically across experimental situations as predicted by the multi-process model.

Adult↗

PubMed2006

Impact of physical and psychological resources on functional autonomy in old age.

Functional autonomy is a core condition of successful ageing. To maximize autonomous functioning is not only a claim of social policy but also primarily an individual need. Part of the challenge of preventing unnecessary dependence in old age is to recognize the diversity among the elderly and the different availability of their physical, psychological and social resources. The aim of this study is to examine the age- and time-related changes in functional autonomy (activities of daily living, ADL, and instrumental activities of daily living, IADL) and the psychophysical resources correlated with these changes in a sample of 441 healthy elderly persons aged 65-95. Furthermore, we are interested in the long-term predictive power of physical resources (objective and subjective health, physical strength) and psychological resources (memory) on functional autonomy. Results show significant age- and time-related deteriorations in functional autonomy and in most psychophysical resources. Structural equation model analyses were performed to test the long-term predictive power of these resources. Results suggest that ADL is better predicted by physical resources than by psychological ones, but for IADL the reverse is the case; here memory variables play a dominant role. Physical and psychological variables are thus specifically related to different components of functional autonomy. This has to be taken into account in the development of preventive and intervention programmes.

Activities of Daily Living↗

PubMed2005

Unconscious word-stem completion priming in a mirror-masking paradigm.

The aim of this study was to investigate unconscious priming by the use of a spatial mirror-masking paradigm. Words and nonwords with no under-length letters are mirrored at their horizontal axis. The results are figures of geometric-like forms that contain letters in their upper part. In the three experiments reported in this study, a priming procedure used such mirrored words and nonwords as primes. Participants were ignorant of the nature of the construction of the stimuli. Perceptual reports of the participants revealed that they did not realize that words were hidden in the primes. Nevertheless, they showed priming in all three experiments. Priming effects were replicated with prime-target SOAs of between 1 and 3 s. Functional dissociations were found between ignorant and informed participants. Informed groups showed perceptual and semantic priming, while ignorant groups showed only perceptual priming.

Female↗