Bianca van Bers
Queen's University Belfast, Psychology, Department Member
This study tested the hypothesis that individuals with dyscalculia have an order processing deficit. The ordering measures included both numerical and non-numerical ordering tasks, and ordering of both familiar and novel sequences was... more
This study tested the hypothesis that individuals with dyscalculia have an order processing deficit. The ordering measures included both numerical and non-numerical ordering tasks, and ordering of both familiar and novel sequences was assessed. Magnitude processing/estimation tasks and measures of inhibition
skills were also administered. The participants were 20 children with developmental dyscalculia, and 20 children without maths difficulties. The two groups were closely matched on age, gender, socio-economic status, educational experiences, IQ and reading ability. The findings revealed differences between the groups in both ordering and magnitude processing skills. Nevertheless, diagnostic status was best predicted by order processing abilities.
skills were also administered. The participants were 20 children with developmental dyscalculia, and 20 children without maths difficulties. The two groups were closely matched on age, gender, socio-economic status, educational experiences, IQ and reading ability. The findings revealed differences between the groups in both ordering and magnitude processing skills. Nevertheless, diagnostic status was best predicted by order processing abilities.
Research Interests:
Mathematics difficulties are common in both children and adults, and they can have a great impact on people's lives. A specific learning disorder in mathematics (SLDM or developmental dyscalculia) is a special case of persistent... more
Mathematics difficulties are common in both children and adults, and they can have a great impact on people's lives. A specific learning disorder in mathematics (SLDM or developmental dyscalculia) is a special case of persistent mathematics difficulties, where the problems with maths cannot be attributed to environmental factors, intellectual disability, or mental, neurological or physical disorders. The aim of the current study was to estimate the prevalence rate of SLDM, any gender differences in SLDM, and the most common comorbid conditions. The DSM-5 provides details regarding these only for specific learning disorders in general, but not specifically for SLDM. We also compared the prevalence rates obtained on the basis of the DSM-IV and DSM-5 criteria. We investigated the performance of 2,421 primary school children on standardized tests of mathematics, English, and IQ, and several demographic factors over the primary school years. We applied the DSM-5 diagnostic criteria to identify children with a potential diagnosis of SLDM. Six per cent of our sample had persistent, severe difficulties with mathematics, and, after applying the exclusion criteria, 5.7% were identified as having an SLDM profile. Both persistent maths difficulties and consistently exceptionally high performance in maths were equally common in males and females. About half of the children with an SLDM profile had some form of language or communication difficulty. Some of these children also had a diagnosis of autism, social, emotional, and behavioural difficulties or attention deficit and hyperactivity disorder. Our findings have important implications for research and intervention purposes, which we discuss in the study.
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What is important for feedback learning in preschoolers Maartje Raijmakers Learning form feedback is an important ability in daily life, but develops at least until late childhood (e.g., van Duijvenvoorde et al., 2006; Minda, Desroches &... more
What is important for feedback learning in preschoolers Maartje Raijmakers Learning form feedback is an important ability in daily life, but develops at least until late childhood (e.g., van Duijvenvoorde et al., 2006; Minda, Desroches & Church, 2008; Schmittmann et al., 2012). However, very little is known about the underlying abilities that are related to feedback learning in preschoolers. For example, cognitive flexibility seems crucial to test hypotheses, but also inhibitory control and short-term memory might be important (Zelazo, 2006). Another important aspect might be the way feedback is provided (Bohlman & Fenson, 2005; Espinet, Anderson & Zelazo, 2013; van Bers et al., 2014). In the current research we tested several hypotheses regarding preschoolers’ difficulty in hypothesis testing. To this end, we designed a very easy hypothesis-testing task, such that performance differences of 3- and 4 years old children would consist of their solution efficiency. The hypotheses were ...
This study investigated the effect of evidence conflicting with preschoolers' naive theory on the patterns of their free exploratory play. The domain of shadow size was used-a relatively complex, ecologically valid domain that allows... more
This study investigated the effect of evidence conflicting with preschoolers' naive theory on the patterns of their free exploratory play. The domain of shadow size was used-a relatively complex, ecologically valid domain that allows for reliable assessment of children's knowledge. Results showed that all children who observed conflicting evidence performed an unconfounded informative experiment in the beginning of their play, compared with half of the children who observed confirming evidence. Mainly, these experiments were directed at investigating a dimension that was at the core of children's initial theory. Thus, preschoolers were flexible in the type of experiments they performed, but they were less flexible in the content of their investigations.
Research Interests:
Research Interests:
Background: The ability to inhibit motor responses, as assessed by the stop-signal reaction time (SSRT), is impaired in children and adolescents with attention-deficit/hyperactivity disorder (ADHD). However, the between-study variation in... more
Background: The ability to inhibit motor responses, as assessed by the stop-signal reaction time (SSRT), is impaired in children and
adolescents with attention-deficit/hyperactivity disorder (ADHD). However, the between-study variation in effect sizes is large. The aim of
this study was to investigate whether this variability can be explained by between-study variation in Go task complexity.
Method: Forty-one studies comparing children or adolescents diagnosed with ADHD to normal control subjects were incorporated in a
random-effects meta-regression analysis. The independent variables were a global index of Go task complexity (i.e., mean reaction time in
control subjects [RTc]) and a more specific index (i.e., spatial compatibility of the stimulus-response mapping). The dependent variable was
the SSRT difference between ADHD and control subjects.
Results: The SSRT difference increased significantly with increasing RTc. Moreover, the SSRT difference was significantly increased in
studies that employed a noncompatible, that is, arbitrary, mapping compared with studies that incorporated a spatially compatible
stimulus-response mapping.
Conclusions: These results indicate that inhibitory dysfunction in children and adolescents with ADHD varies with task complexity:
inhibitory dysfunction in ADHD is most pronounced for spatially noncompatible responses. Explanations in terms of inhibition and working
memory deficits and a tentative neurobiological explanation are briefly discussed.
adolescents with attention-deficit/hyperactivity disorder (ADHD). However, the between-study variation in effect sizes is large. The aim of
this study was to investigate whether this variability can be explained by between-study variation in Go task complexity.
Method: Forty-one studies comparing children or adolescents diagnosed with ADHD to normal control subjects were incorporated in a
random-effects meta-regression analysis. The independent variables were a global index of Go task complexity (i.e., mean reaction time in
control subjects [RTc]) and a more specific index (i.e., spatial compatibility of the stimulus-response mapping). The dependent variable was
the SSRT difference between ADHD and control subjects.
Results: The SSRT difference increased significantly with increasing RTc. Moreover, the SSRT difference was significantly increased in
studies that employed a noncompatible, that is, arbitrary, mapping compared with studies that incorporated a spatially compatible
stimulus-response mapping.
Conclusions: These results indicate that inhibitory dysfunction in children and adolescents with ADHD varies with task complexity:
inhibitory dysfunction in ADHD is most pronounced for spatially noncompatible responses. Explanations in terms of inhibition and working
memory deficits and a tentative neurobiological explanation are briefly discussed.
Research Interests:
A widely used paradigm to study cognitive flexibility in preschoolers is the Dimensional Change Card Sorting (DCCS) task. The developmental dynamics of DCCS performance was studied in a cross-sectional design (N = 93, 3 to 5 years of age)... more
A widely used paradigm to study cognitive flexibility in preschoolers is the Dimensional Change Card Sorting (DCCS) task.
The developmental dynamics of DCCS performance was studied in a cross-sectional design (N = 93, 3 to 5 years of age) using
a computerized version of the standard DCCS task. A model-based analysis of the data showed that development on the DCCS
task is best described as a discontinuous change in performance on the post-switch phase of the task. In addition to a
perseveration group and a switch group, a transitional group that showed shifts between perseverating and switching during the
post-switch trials could be distinguished. Computational models of performance and development on the DCCS task cannot, in
their current forms, explain these results. We discuss how a catastrophe model of the developmental changes in task performance
could be used to generate specific hypotheses about the variables that control development of DCCS performance.
The developmental dynamics of DCCS performance was studied in a cross-sectional design (N = 93, 3 to 5 years of age) using
a computerized version of the standard DCCS task. A model-based analysis of the data showed that development on the DCCS
task is best described as a discontinuous change in performance on the post-switch phase of the task. In addition to a
perseveration group and a switch group, a transitional group that showed shifts between perseverating and switching during the
post-switch trials could be distinguished. Computational models of performance and development on the DCCS task cannot, in
their current forms, explain these results. We discuss how a catastrophe model of the developmental changes in task performance
could be used to generate specific hypotheses about the variables that control development of DCCS performance.
Research Interests:
Training cognitive flexibility in preschoolers is of great interest but is not easy to achieve. In three experiments, we studied the effects of feedback on preschoolers’ switch behavior with a computerized version of the Dimensional... more
Training cognitive flexibility in preschoolers is of great interest but
is not easy to achieve. In three experiments, we studied the effects
of feedback on preschoolers’ switch behavior with a computerized
version of the Dimensional Change Card Sorting (DCCS) task. The
task was designed such that feedback was connected to the stimulus
and causally related to children’s behavior. Experiments 1 and 2
showed that children receiving feedback on their post-switch
behavior performed better than children administered a standard
(no feedback) DCCS task. This effect transferred to a subsequent
standard DCCS task after 5 min and after 1 week. Experiment 3
showed that children switched to the new post-switch sorting
rules and not to rules that oppose the pre-switch sorting rules.
These results highlight preschoolers’ sensitivity to the design of
feedback in learning an abstract rule.
is not easy to achieve. In three experiments, we studied the effects
of feedback on preschoolers’ switch behavior with a computerized
version of the Dimensional Change Card Sorting (DCCS) task. The
task was designed such that feedback was connected to the stimulus
and causally related to children’s behavior. Experiments 1 and 2
showed that children receiving feedback on their post-switch
behavior performed better than children administered a standard
(no feedback) DCCS task. This effect transferred to a subsequent
standard DCCS task after 5 min and after 1 week. Experiment 3
showed that children switched to the new post-switch sorting
rules and not to rules that oppose the pre-switch sorting rules.
These results highlight preschoolers’ sensitivity to the design of
feedback in learning an abstract rule.
Research Interests:
The abstractness of rule representations in the pre-switch phase of the Dimensional Change Card Sorting (DCCS) task was studied by letting 3- and 4-year-old children perform a standard DCCS task and a separate generalization task. In the... more
The abstractness of rule representations in the pre-switch phase of
the Dimensional Change Card Sorting (DCCS) task was studied by
letting 3- and 4-year-old children perform a standard DCCS task
and a separate generalization task. In the generalization task, children
were asked to generalize their sorting rules to novel stimuli in
one of three conditions. In the relevant change condition, values of
the relevant dimension changed; in the irrelevant change condition,
values of the irrelevant dimension changed; and in the total change
condition, values of both dimensions changed. All children showed
high performance on the generalization task in the relevant change
condition, implying an abstract rule representation at the level of
dimensions (‘‘same colors go together’’). Performance in the relevant
change condition was significantly better (and faster) than
performance in the other two conditions. Children with high cognitive
flexibility (switchers on the DCCS task) more often switched
their attention to the irrelevant dimension in the generalization
task only if values of the irrelevant dimension changed. Children
with low cognitive flexibility (perseverators) were more often
inconsistent in their sorting on the generalization task if values
of both dimensions changed. The difference in performance on
the DCCS task between switchers and perseverators seems to result
from the processes that operate on the learned sorting rules and
not from the abstractness of the rule representations children have.
the Dimensional Change Card Sorting (DCCS) task was studied by
letting 3- and 4-year-old children perform a standard DCCS task
and a separate generalization task. In the generalization task, children
were asked to generalize their sorting rules to novel stimuli in
one of three conditions. In the relevant change condition, values of
the relevant dimension changed; in the irrelevant change condition,
values of the irrelevant dimension changed; and in the total change
condition, values of both dimensions changed. All children showed
high performance on the generalization task in the relevant change
condition, implying an abstract rule representation at the level of
dimensions (‘‘same colors go together’’). Performance in the relevant
change condition was significantly better (and faster) than
performance in the other two conditions. Children with high cognitive
flexibility (switchers on the DCCS task) more often switched
their attention to the irrelevant dimension in the generalization
task only if values of the irrelevant dimension changed. Children
with low cognitive flexibility (perseverators) were more often
inconsistent in their sorting on the generalization task if values
of both dimensions changed. The difference in performance on
the DCCS task between switchers and perseverators seems to result
from the processes that operate on the learned sorting rules and
not from the abstractness of the rule representations children have.
Research Interests:
This study investigated the effect of evidence conflicting with preschoolers' naive theory on the patterns of their free exploratory play. The domain of shadow size was used-a relatively complex, ecologically valid domain that allows... more
This study investigated the effect of evidence conflicting with preschoolers' naive theory on the patterns of their free exploratory play. The domain of shadow size was used-a relatively complex, ecologically valid domain that allows for reliable assessment of children's knowledge. Results showed that all children who observed conflicting evidence performed an unconfounded informative experiment in the beginning of their play, compared with half of the children who observed confirming evidence. Mainly, these experiments were directed at investigating a dimension that was at the core of children's initial theory. Thus, preschoolers were flexible in the type of experiments they performed, but they were less flexible in the content of their investigations.
Research Interests:
Research Interests:
De Nederlandse versie van de Wechsler Intelligence Scale for Children (wisc) werd in 2002 in een nieuwe versie op de markt gebracht als wisc-iii nl. Deze versie werd al snel onderwerp van discussie en kreeg heftige kritieken te verduren.... more
De Nederlandse versie van de Wechsler Intelligence Scale for Children (wisc) werd in 2002 in een nieuwe versie op de markt gebracht als wisc-iii nl. Deze versie werd al snel onderwerp van discussie en kreeg heftige kritieken te verduren. Normering en validiteit werden door de cotan als onvoldoende beoordeeld. In dit onderzoek is nagegaan hoe de wisc-iii nl in de praktijk gebruikt wordt. Kopers van deze intelligentietest (n = 876) werden in april 2004 benaderd met een daartoe ontworpen enquête. Onderzocht is het feitelijk gebruik van de wisc in de periode 2002-2003 en de prognose van het gebruik in 2004. Verder is gebruikers gevraagd naar hun oordeel over de kwaliteit van de test en hun opinie over de discussie en publiekelijk geuite kritiek. Uit de resultaten van het onderzoek (n = 476) kwam naar voren dat de meeste respondenten een tot twintig kinderen per jaar testten, de meesten in de leeftijd van negen tot elf jaar en vooral voor diagnose van leermoeilijkheden, toewijzing tot speciale onderwijsprogramma’s of voor klinische diagnose. De algemene indruk van de gebruikers betreffende de kwaliteit de wisc-iii nl was goed. Op specifieke punten oordeelde men overeenkomstig de cotan. Tot slot werd er opvallend veel gebruik gemaakt van de mogelijkheid om aanvullende opmerkingen te maken over de discussie rond de wisc-iii nl en over het gebruik van de test.