Biomedical subjects

Klaus Oberauer

Publications and source records attributed to Klaus Oberauer.

13 recordsLinked to original sources

PubMed2005

Working memory and intelligence--their correlation and their relation: comment on Ackerman, Beier, and Boyle (2005).

On the basis of a meta-analysis of pairwise correlations between working memory tasks and cognitive ability measures, P. L. Ackerman, M. E. Beier, and M. O. Boyle (2005; see record 2004-22408-002) claimed that working memory capacity (WMC) shares less than 25% of its variance with general intelligence (g) and with reasoning ability. In this comment, the authors argue that this is an underestimation because of several methodological shortcomings and biases. A reanalysis of the data reported in Ackerman et al. using the correct statistical procedures demonstrates that g and WMC are very highly correlated. On a conceptual level, the authors point out that WMC should be regarded as an explanatory construct for intellectual abilities. Theories of working memory do not claim that WMC is isomorphic with intelligence factors but that it is a very strong predictor of reasoning ability and also predicts general fluid intelligence and g.

Humans↗

PubMed2005

Binding and inhibition in working memory: individual and age differences in short-term recognition.

Two studies investigated the relationship between working memory capacity (WMC), adult age, and the resolution of conflict between familiarity and recollection in short-term recognition tasks. Experiment 1 showed a specific deficit of young adults with low WMC in rejecting intrusion probes (i.e., highly familiar probes) in a modified Sternberg task, which was similar to the deficit found in old adults in a parallel experiment (K. Oberauer, 2001). Experiment 2 generalized these results to 3 recognition paradigms (modified Sternberg, local recognition, and n back tasks). Old adults showed disproportional performance deficits on intrusion probes only in terms of reaction times, whereas young adults with low WMC showed them only in terms of errors. The generality of the effect across paradigms is more compatible with a deficit in content-context bindings subserving recollection than with a deficit in inhibition of irrelevant information in working memory. Structural equation models showed that WMC is related to the efficiency of recollection but not of familiarity.

Adolescent↗

PubMed2005

Control of the contents of working memory--a comparison of two paradigms and two age groups.

Two experiments investigated whether young and old adults can temporarily remove information from a capacity-limited central component of working memory (WM) into another component, the activated part of long-term memory (LTM). Experiment 1 used a modified Sternberg recognition task (S. Sternberg, 1969); Experiment 2 used an arithmetic memory-updating task. In both paradigms, participants memorized 2 lists, one of which was cued as temporarily irrelevant. Removal of the irrelevant list from capacity-limited WM was indexed by the disappearance of list-length effects of that list on latencies for concurrent processing tasks. Young adults could outsource the irrelevant list within 2-3 s and retrieve it back into the central part of WM later. Old adults showed the same flexibility in the arithmetic updating task but seemed somewhat less able or inclined to temporarily move information into the activated part of LTM in the modified Sternberg task.

Adult↗

PubMed2005

Effects of directionality in deductive reasoning: II. Premise integration and conclusion evaluation.

Previous research (Oberauer & Wilhelm, 2000) has shown an inherent directionality between the two terms linked in premises of typical deductive reasoning tasks. With three experiments we investigated the effect of inherent directionality on the time to integrate two premises and for the derivation of a conclusion. We varied figure (i.e., order of terms in the premises) and direction of inference (i.e., order of terms in the conclusion) in deduction tasks from various domains (propositional reasoning, syllogisms, spatial, temporal, and linear order reasoning). Effects of figure on premise reading times varied with the directionality of the relations. Effects of direction of inference reflected the same directionality for a subset of relations. We propose that two factors are jointly responsible for a large part of observed directionality effects in premise integration: the inherent directionality of relational statements and a general advantage for a given-new order of terms in the second premise. Difficulty of deriving a conclusion is affected by the directionality or relations if and only if the relation is semantically asymmetric, so that the directionality must be preserved in the integrated mental model.

Humans↗

PubMed2005

Memory for fact, fiction, and misinformation: the Iraq War 2003.

Media coverage of the 2003 Iraq War frequently contained corrections and retractions of earlier information. For example, claims that Iraqi forces executed coalition prisoners of war after they surrendered were retracted the day after the claims were made. Similarly, tentative initial reports about the discovery of weapons of mass destruction were all later disconfirmed. We investigated the effects of these retractions and disconfirmations on people's memory for and beliefs about war-related events in two coalition countries (Australia and the United States) and one country that opposed the war (Germany). Participants were queried about (a) true events, (b) events initially presented as fact but subsequently retracted, and (c) fictional events. Participants in the United States did not show sensitivity to the correction of misinformation, whereas participants in Australia and Germany discounted corrected misinformation. Our results are consistent with previous findings in that the differences between samples reflect greater suspicion about the motives underlying the war among people in Australia and Germany than among people in the United States.

Adolescent↗

PubMed2005

Two principles of premise integration in spatial reasoning.

We propose two principles that facilitate integration of two relational premises in spatial reasoning. Integration is easier if the anaphor in the second premise, P2, bears the role of the relatum (relatum = given). Moreover, integration is easier if, in P2, the anaphor is mentioned before the new element (given-new). In premises with canonical word order (grammatical subjects mentioned first), these principles always conflict with one another. In topicalized statements mentioning the prepositional phrase first, the two principles work in tandem. By varying word order, we tested the two principles by measuring P2 comprehension times. Comprehension times indicated that integration was easiest when P2 obeyed both principles and most difficult when both principles were violated. Canonical premises were of intermediate difficulty. This pattern emerged regardless of whether the anaphor was a definite description or a pronoun.

Adolescent↗

PubMed2004

Simultaneous cognitive operations in working memory after dual-task practice.

The authors tested the hypothesis that with adequate practice, people can execute 2 cognitive operations in working memory simultaneously. In Experiment 1, 6 students practiced updating 2 items in working memory through 2 sequences of operations (1 numerical, 1 spatial). In different blocks, imperative stimuli for the 2 sequences of operations were presented either simultaneously or sequentially. Initially, most participants experienced substantial dual-task costs. After 24 sessions of practice, operation latencies for simultaneous presentation were equal to the maximum of times for the 2 operations in the sequential condition, suggesting perfect timesharing. Experiment 2 showed that a reduction of dual-task costs requires practice on the combination of the 2 updating tasks, not just practice on each individual task. Hence, the reduction of dual-task costs cannot be explained by shortening or automatization of individual operations.

Cognition↗

PubMed2004

Logical reasoning and probabilities: a comprehensive test of Oaksford And Chater (2001).

We report two experiments testing a central prediction of the probabilistic account of reasoning provided by Oaksford and Chater (2001): Acceptance of standard conditional inferences, card choices in the Wason selection task, and quantifiers chosen for conclusions from syllogisms should vary as a function of the frequency of the concepts involved. Frequency was manipulated by a probability-learning phase preceding the reasoning tasks to simulate natural sampling. The effects predicted by Oaksford and Chater (2001) were not obtained with any of the three paradigms.

Adolescent↗

PubMed2003

Selective attention to elements in working memory.

Three experiments with an arithmetic working memory task examine the object switch effect first reported by Garavan (1998), which was interpreted as evidence for a focus of attention within working memory. Experiments 1a and 1b showed object switch costs with a task that requires selective access to items in working memory, but did not involve counting, and did not require updating of working memory contents, thus ruling out two alternative explanations of Garavan's results. Experiment 2 showed object switch costs with a task that required no selective access to working memory contents, but involved updating, thus providing evidence for a second component to the overall object switch costs. Further analyses revealed that the object switch cost increased with memory set size; that there were (smaller) switch costs when the switch was to an item of the same type; that repeating an arithmetic operation does not have the same effect as repeating the object it is applied to; and that object switching is not mediated by backward inhibition of the previously focused object.

Adult↗

PubMed2003

The meaning(s) of conditionals: conditional probabilities, mental models, and personal utilities.

Five experiments were conducted to test the hypothesis that people understand conditional statements ("if p then q") as indicating a high conditional probability P(q/p). Participants estimated the probability that a given conditional is true (Experiments 1A, 1B, and 3) or judged whether a conditional was true or false (Experiments 2 and 4) given information about the frequencies of the relevant truth table cases. Judgments were strongly influenced by the ratio of pq to p not q cases, supporting the conditional probability account In Experiments 1A, 1B, and 3, judgments were also affected by the frequency of pq cases, consistent with a version of mental model theory. Experiments 3 and 4 extended the results to thematic conditionals and showed that the pragmatic utility associated with believing a statement also affected the degree of belief in conditionals but not in logically equivalent quantified statements.

Adolescent↗

PubMed2003

Age differences in working memory--the roles of storage and selective access.

Twenty-four young (23 years) and 24 old (71 years) adults performed arithmetic tasks with working memory loads ranging from 1 to 4. Age groups were equivalent in mean accuracy and speed of arithmetic operations under minimal working memory load, but old adults were slower than young with memory demands >1. Access to a new object in working memory as the basis of computation required additional time. This object-switching cost increased with increases in memory demand, but was unaffected by age, indicating that old adults have no deficit in selective access to working memory.

Adult↗

PubMed2002

Access to information in working memory: exploring the focus of attention.

Participants memorized briefly presented sets of digits, a subset of which had to be accessed as input for arithmetic tasks (the active set), whereas another subset had to be remembered independently of the concurrent task (the passive set). Latencies for arithmetic operations were a function of the setsize of active but not passive sets. Object-switch costs were observed when successive operations were applied to different digits within an active set. Participants took 2 s to encode a passive set so that it did not affect processing latencies (Experiment 2). The results support a model distinguishing 3 states of representations in working memory: the activated part of long-term memory, a capacity limited region of direct access, and a focus of attention.

Adult↗

PubMedDate not supplied

Overwriting of phonemic features in serial recall.

We tested two explanations of the phonological similarity effect in verbal short-term memory: The confusion hypothesis assumes that serial positions of similar items are confused. The overwriting hypothesis states that similar items share feature representations, which are overwritten. Participants memorised a phonologically dissimilar list of CVC-trigrams (Experiment 1) or words (Experiment 2 and 3) for serial recall. In the retention interval they read aloud other items. The material of the distractor task jointly overlapped one item of the memory list. The recall of this item was impaired, and the effect was not based on intrusions from the distractor task alone. The results provide evidence for feature overwriting as one potential mechanism contributing to the phonological similarity effect.

Humans↗