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Paul van den Broek

Publications and source records attributed to Paul van den Broek.

17 recordsLinked to original sources
PubMed2006

Hemispheric processing of inferences: the effects of textual constraint and working memory capacity.

In this study, we investigated hemispheric differences in the generation of bridging and predictive inferences. Participants read texts that provided either strong or weak causal constraints for a particular bridging (Experiment 1) or predictive (Experiment 2) inference and performed a lexical decision task to inference-related targets presented to the left or the right hemisphere. Facilitation for strongly constrained bridging and predictive inferences was found in both hemispheres. In contrast, facilitation for weakly constrained inferences was stronger in the right than in the left hemisphere for both bridging and predictive inferences, although for the latter there was some facilitation in the left hemisphere as well. We also considered whether these effects differ as a function of the working memory capacity of the reader. High working memory capacity readers showed greater facilitation for strongly constrained inferences than for weakly constrained inferences in both hemispheres, whereas low working memory capacity readers showed this same pattern in the left hemisphere but showed equal facilitation for strongly and weakly constrained inferences in the right hemisphere. These results suggest that hemispheric processing, textual constraint, and working memory capacity interact to affect how readers generate causal inferences.

Adolescent↗
PubMed2005

Evidence for dissociable neural mechanisms underlying inference generation in familiar and less-familiar scenarios.

In this study, we investigated whether the left and right hemispheres are differentially involved in causal inference generation. Participants read short inference-promoting texts that described either familiar or less-familiar scenarios. After each text, they performed a lexical decision on a letter string (which sometimes constituted an inference-related word) presented directly to the left or right hemisphere. Response-time results indicated that hemisphere of direct presentation interacted with type of inference scenario. When test stimuli were presented directly to the left hemisphere, lexical decisions were facilitated following familiar but not following less-familiar inference scenarios, whereas when test stimuli were presented directly to the right hemisphere, facilitation was observed in both familiar and less-familiar conditions. Thus, inferences may be generated in different ways depending on which of two dissociable neural subsystems underlies the activation of background information.

Adult↗
PubMed2005

The computational implementation of the landscape model: modeling inferential processes and memory representations of text comprehension.

The complexity of text comprehension demands a computational approach to describe the cognitive processes involved. In this article, we present the computational implementation of the landscape model of reading. This model captures both on-line comprehension processes during reading and the off-line memory representation after reading is completed, incorporating both memory-based and coherence-based mechanisms of comprehension. The overall architecture and specific parameters of the program are described, and a running example is provided. Several studies comparing computational and behavioral data indicate that the implemented model is able to account for cycle-by-cycle comprehension processes and memory for a variety of text types and reading situations.

Cognition↗
PubMed2005

Causal coherence and the availability of locations and objects during narrative comprehension.

The aim of this study was to examine whether locations of objects are encoded and available to the reader at different points in a narrative, depending on their causal relevance. Participants in five experiments read narratives in which the spatial relation between an object and its location either did or did not provide a causal explanation for a later critical event. Object and location target words were presented to the participants immediately before or after the critical event. Speeded recognition response times to target words demonstrated that both locations and objects were reactivated, but only after they became causally relevant. The results suggest that the causal structure of a text can influence the availability of spatial information and that at least some spatial relations are encoded during reading and are available to the reader when they are needed to build coherence.

Cognition↗
PubMed2004

Hemispheric processing of anaphoric inferences: the activation of multiple antecedents.

This research investigates the hemispheric processing of anaphors when readers activate multiple antecedents. Participants read texts promoting an anaphoric inference and performed a lexical decision task to inference-related target words that were consistent (Experiment 1) or inconsistent (Experiment 2) with the text. These targets were preceded by constrained or less constraining text and were presented to participants' right visual field-left hemisphere or to their left visual field-right hemisphere. In Experiment 1, both hemispheres showed facilitation for consistent antecedents and the right hemisphere showed an advantage over the left hemisphere in processing antecedents when preceded by less constrained text. In Experiment 2, the left hemisphere only showed negative facilitation for inconsistent antecedents. When readers comprehend text with multiple antecedents: both hemispheres process consistent information, the left hemisphere inhibits inconsistent information, and the right hemisphere processes less constrained information.

Cerebral Cortex↗
PubMed2004

Policy relevance of Bayesian statistics overestimated?

OBJECTIVES: The observed posterior probability distributions regarding the benefits of surgery for otitis media with effusion (OME) with expected probability distributions, using Bayes' theorem are compared. METHODS: Postal questionnaires were used to assess prior and posterior probability distributions among ear-nose-throat (ENT) surgeons in the Netherlands. RESULTS: In their prior probability estimates, ENT surgeons were quite optimistic with respect to the effectiveness of tube insertion in the treatment of OME. The trial showed no meaningful benefit of tubes on hearing and language development. Posterior probabilities calculated on the basis of prior probability estimates and trial results differed widely from those, elicited empirically 1 year after completion of the trial and dissemination of the results. CONCLUSIONS: ENT surgeons did not adjust their opinion about the benefits of surgical treatment of glue ears to the extent that they should have done according to Bayes' theorem. Users of the results of Bayesian analyses, notably policy-makers, should realize that Bayes' theorem is prescriptive and not necessarily descriptively correct. Health policy decisions should not be based on the untested assumption that health-care professionals use new evidence to adjust their subjective beliefs in a Bayesian manner.

Attitude of Health Personnel↗
PubMed2004

Difficulties in comprehending causal relations among children with ADHD: the role of cognitive engagement.

The present study examined whether time spent in long looks (i.e., >or=15 s), an index of cognitive engagement, would account for differences between children with attention deficit hyperactivity disorder (ADHD) and comparison children in understanding causal relations. Children viewed two televised stories, once in the presence of toys and once in their absence. Dependent variables were visual attention and questions tapping factual information and causal relations. Comparison children answered significantly more causal relations questions than did the children with ADHD, but only in the toys-present condition. Four lines of evidence revealed that the difficulties children with ADHD had in answering causal relations questions in the toys-present condition could be linked specifically to this group's decreased time spent in long looks.

Attention↗
PubMed2004

Development of auditory processing in 6-12-year-old children: a longitudinal study.

The development of auditory processing in children was investigated in a longitudinal study. A group of 20 children with normal cognitive and language development underwent several auditory tests at the ages of 6, 7, 8, 10 and 12 years. At the age of 10 years, three subjects were lost to follow-up, as was one more subject at the age of 12 years. The auditory performance of the children was compared to the performance of a group of 20 adults. The auditory test battery consisted of a speech-in-noise test, a filtered speech test, a binaural fusion test and two auditory sequencing tests. At the ages of 6, 7 and 8 years, data on the performance on an auditory word discrimination test, an auditory synthesis test, an auditory closure test and a number recall test were also obtained. All auditory tests except the speech-in-noise test showed a clear effect of age on the performance of children. Our data suggest that maturational effects play an important role in auditory processing (at least) up to an age of 12-13 years. Correlations between the tests are in general not indicative of large amounts of overlap between the different tests. Factor analysis shows that three factors account for 68-70% of explained variance, with the three factors contributing equally. A composite score obtained by averaging all (sub)test scores can be used next to the individual test scores to describe the development of auditory processing abilities in children.

Adult↗
PubMed2004

Development of an auditory test battery for young children: a pilot study.

This article describes the development and results of a pilot study with a recently developed auditory test battery for 4-6-year-old Dutch children. The test battery consisted of a sustained auditory attention (SAA) test, a dichotic words (DW) test, a binaural masking-level difference (BMLD) test, an auditory word discrimination (AWD) test, a gap detection (GD) test and a test of phonemic awareness, the Lindamood Auditory Conceptualization (LAC) test. Our results show that this test battery can be administered successfully to children aged 4 years and older. Most tests showed a clear effect of chronological age; the strongest age effects were found for the DW test and the LAC test. The BMLD test was the only test for which no significant age effect was found in this group of children. A small, but significant right-ear advantage was found on the DW test, for the 4- and the 6-year-olds. Correlations between subtests were in general rather high, suggesting that several tests in this test battery may be tapping into similar auditory abilities.

Age Factors↗
PubMed2003

Comparison of different speech coding strategies using a disability-based inventory and speech perception tests in quiet and in noise.

OBJECTIVE: Intraindividual comparison of two cochlear implant speech coding strategies implemented in the Nucleus 24M system (SPEAK versus ACE). Reasons for subjective preference were evaluated using a combination of speech perception scores and a disability-based inventory. STUDY DESIGN: Cross-over study with two groups of cochlear implant subjects, assigned to first receive ACE or SPEAK strategy. SETTING: Cochlear implant program. SUBJECTS: Twelve postlingually deaf adults using a Nucleus 24M cochlear implant system. INTERVENTION: Subjects consecutively used the two different speech coding strategies and completed speech perception tests in quiet and in noise and a disability-based inventory (Abbreviated Profile of Hearing Aid Benefit). MAIN OUTCOME MEASURES: Individual differences between the two different speech coding strategies and the relation with subjective strategy preference. RESULTS: The ACE strategy produced somewhat better speech recognition scores in quiet and in noise, although the difference in the scores in noise did not reach the 95% level of significance. The first coding strategy chosen did not affect the results or subjective preference. Preference according to the APHAB results were not a priori in conformity with the speech recognition scores. CONCLUSION: Most subjects preferred the ACE strategy. Subjective preference was in agreement with the APHAB results in three subjects, in agreement with speech recognition in two subjects, and in agreement with both in seven subjects. The present results support the use of both speech recognition tests and questionnaires to evaluate different speech coding strategies.

Adult↗
PubMed2003

Auditory processing in patients with Charcot-Marie-Tooth disease type 1A.

HYPOTHESIS: It is unclear whether Charcot-Marie-Tooth (CMT) disease, type 1A, causes auditory processing disorders. Therefore, auditory processing abilities were investigated in five CMT1A patients with normal hearing. BACKGROUND: Previous studies have failed to separate peripheral from central auditory processing disorders. MATERIALS AND METHODS: Five genetically confirmed CMT1A cases in patients with normal hearing underwent behavioral and objective testing. Pure tone audiometry, speech audiometry, and OAE assessment were followed-up by an auditory processing test battery comprising sentences-in-noise test, pattern recognition tests, words-in-noise test, dichotic digit test, filtered speech test, binaural fusion test, and categorical speech perception test. Subsequently, ABR and ERP measurements were conducted. RESULTS: Either the behavioral or objective test scores of 4 out of the 5 CMT1A patients did not differ significantly from those of subjects with normal hearing. Significantly lower scores of one patient on auditory processing tests and ABR measurements could be ascribed to subnormal hearing. CONCLUSION: The authors conclude that CMT1A patients with normal peripheral hearing have auditory processing abilities that were not indicative for an auditory processing disorder. Furthermore, the presence of a peripheral hearing loss complicates the interpretation of auditory processing abilities.

Acoustic Stimulation↗
PubMed2003

Auditory processing disorders in adults and children: evaluation of a test battery.

A Dutch test battery comprising six different tests for auditory processing disorders was evaluated in a group of 49 adults and children (age 8-57 years) with auditory complaints despite normal audiometric thresholds. Percentile scores were derived from normal control groups (n = 132) to determine whether a subject passed or failed a test. A composite score was computed to reflect a general score on all the auditory processing tests. In order to gain insight into underlying auditory processes, factor analysis was performed. Normal scores on all the tests were seen in five subjects. The remaining 44 subjects had at least one test score that was below the cut-off point (10th percentile). Factor analysis provided evidence for a model comprising four auditory components: auditory sequencing, word recognition in noise, auditory closure, and auditory patterning. This model could be useful in the interpretation of scoring patterns. Although there were some differences in scoring patterns between the children and adults, the test battery proved to be useful in both groups.

Acoustic Stimulation↗
PubMed2003

Assessment of auditory processing in 6-year-old language-impaired children.

The performance of a group of twenty 6-year-old children with specific language impairment (SLI) on several behavioural auditory tests was compared to that of a group of twenty age-matched control children. The auditory test battery used in this study consisted of the following tests: a speech-in-noise test, a filtered speech test, a binaural fusion test, a frequency pattern test, a duration pattern test, a temporal integration test, an auditory word discrimination test, an auditory synthesis test, an auditory closure test and a number recall test. Our results show that the SLI children obtained scores on almost all tests that were significantly lower than those of the control group. Many of the basic auditory processing measures in our test battery correlated significantly with receptive and language scores, suggesting a (causal) relationship between auditory processing and language proficiency. Results from discriminant function analyses do not warrant deleting one or more tests from the test battery yet (with the exception of the auditory synthesis test and the temporal integration test, for which we did not find significant group effects). At present, we are conducting experiments with older (SLI and control) children and adults to find whether the significant performance deficits of the SLI children are also found in older SLI children, and to determine the influence of maturational effects on these auditory tests.

Case-Control Studies↗
PubMed2002

Age effects and normative data on a Dutch test battery for auditory processing disorders.

A test battery compiled to diagnose auditory processing disorders (APDs) in an adult population was used on a population of 9-16-year-old children. The battery consisted of eight tests (words -in noise, filtered speech, binaural fusion, dichotic digits, frequency and duration patterns, backward masking, categorical perception, digit span) and a questionnaire. Descriptive statistics were computed on data obtained from 75 children from primary school (age 9-12 years) and 30 adolescents from secondary school (age 14-16 years) with normal hearing and normal intelligence. Most test scores did not follow a normal distribution. Age effects were present in most tests, within the group as well as when children and adolescents were compared to adults. This suggests that maturation of auditory processing abilities takes place even during adolescence. Relative measures regarding ear differences and binaural versus monaural scores did not appear to be age-related. These measures might be useful in diagnosing APD, supplementary to the absolute measures. Factor analysis showed four components that address underlying processes. However, these results must be interpreted cautiously because the study did not include any subjects with APD.

Adolescent↗
PubMed2002

Evaluation of cochlear implant benefit with auditory cortical evoked potentials.

Endogenous P300 and exogenous slow vertex potentials were obtained with tone and speech stimuli in a group of five children using a cochlear implant (CI) with poor speech recognition (group A) and compared with those from another group of five children using a CI with good speech recognition (group B). The responses were also compared to those of children with normal hearing (n= 14) and a group of adult CI users (n=9). N1 and P2 latencies of CI group A and group B were prolonged compared to those of normally-hearing children. In group A, P300 was present when contrasts with tone stimuli were used. When speech stimuli were used, P300 potentials were absent or delayed. P300 potentials obtained in group B were no different from those obtained in normally-hearing children. It is suggested that the poor results evoked with speech stimuli in contrast to those evoked with pure-tone stimuli in group A are due to the immaturity of (sub) cortical generators associated with acoustical and phonetic processing. In contrast to the children in group B, all children in group A suffered from congenital deafness.

Adolescent↗
PubMed2000

Comprehension of televised stories in boys with attention deficit/hyperactivity disorder and nonreferred boys.

Two studies compared comprehension of televised stories by 7- to 12-year-old boys with attention deficit/hyperactivity disorder (ADHD) and nonreferred comparison boys. Boys watched one show with toys present and one with toys absent. Visual attention was continuously recorded, and recall was tested after each show. Across studies, visual attention was high with toys absent but decreased sharply with toys present for boys with ADHD. Groups showed similar levels of cued recall of discrete units of information regardless of differences in attention. When recall tasks and television story structure required knowledge of relations among events, the reduced attention of boys with ADHD interfered with recall. Although visual attention of comparison boys also decreased to some extent with toys present, there was no such decrement in recall. Implications of the difficulties children with ADHD have in integrated story comprehension are discussed.

Attention↗