Henrik Danielsson

The Ease of Language Understanding (ELU) model: theoretical, empirical, and clinical advances

Working memory is important for online language processing during conversation. We use it to maintain relevant information, to inhibit or ignore irrelevant information, and to attend to conversation selectively. Working memory helps us to keep track of and actively participate in conversation, including taking turns and following the gist. This paper examines the Ease of Language Understanding model (i.e., the ELU model, Rönnberg, 2003; Rönnberg et al., 2008) in light of new behavioral and neural findings concerning the role of working memory capacity (WMC) in uni-modal and bimodal language processing. The new ELU model is a meaning prediction system that depends on phonological and semantic interactions in rapid implicit and slower explicit processing mechanisms that both depend on WMC albeit in different ways. It is based on findings that address the relationship between WMC and (a) early attention processes in listening to speech, (b) signal processing in hearing aids and its effects on short-term memory, (c) inhibition of speech maskers and its effect on episodic long-term memory, (d) the effects of hearing impairment on episodic and semantic long-term memory, and finally, (e) listening effort. New predictions and clinical implications are outlined. Comparisons with other WMC and speech perception models are made.

Strengths and weaknesses in executive functioning in children with intellectual disability

Children with intellectual disability (ID) were given a comprehensive range of executive functioning measures, which systematically varied in terms of verbal and non-verbal demands. Their performance was compared to the performance of groups matched on mental age (MA) and chronological age (CA), respectively. Twenty-two children were included in each group. Children with ID performed on par with the MA group on switching, verbal executive-loaded working memory and most fluency tasks, but below the MA group on inhibition, planning, and non-verbal executive-loaded working memory. Children with ID performed below CA comparisons on all the executive tasks. We suggest that children with ID have a specific profile of executive functioning, with MA appropriate abilities to generate new exemplars (fluency) and to switch attention between tasks, but difficulties with respect to inhibiting pre-potent responses, planning, and non-verbal executive-loaded working memory The development of different types of executive functioning skills may, to different degrees, be related to mental age and experience.

Executive functions in individuals with intellectual disability

The aim of the present study was to investigate executive functions in adults with intellectual disability, and compare them to a closely matched control group longitudinally for 5 years. In the Betula database, a group of adults with intellectual disability (ID, n=46) was defined from measures of verbal and non-verbal IQ. A control group, with two people for every person with intellectual disability (n=92), was chosen by matching on the following criterion in order of priority: IQ higher than 85, age, sex, sample, level of education, and years of education. Three types of tasks of executive functions were included on two occasions, with 5 years between testing sessions: The Tower of Hanoi, executively loaded dual task versions of word recall, and verbal fluency. Adults with ID showed significant impairments on verbal fluency and on the executively loaded dual task word recall task (at encoding but not at recall). There were no group differences on the Tower of Hanoi. No significant differences between the two test occasions were found. The results are interpreted in terms of individuals with ID having problems with speed of accessing lexical items and difficulties with working memory-related executive control at encoding, which includes shifting between tasks. There are, however, not necessarily problems with inhibition. The dual task results additionally imply that the adults with intellectual disability were more sensitive to strategy interruptions at encoding, but that dividing attention at recall did not have such detrimental effects.

Empathy among students in engineering programs

Engineers face challenges when they are to manage project groups and be leaders for organisations because such positions demand skills in social competence and empathy. Previous studies have shown that engineers have low degrees of social competence skills. In this study, the level of empathy as measured by the four subscales of the Interpersonal Reactivity Index, perspective taking, fantasy, empathic distress and empathic concern, among engineering students was compared to students in health care profession programmes. Participants were undergraduate students at Linköping University, 365 students from four different health care profession programmes and 115 students from two different engineering programmes. When the empathy measures were corrected for effects of sex, engineering students from one of the programmes had lower empathy than psychology and social worker students on the fantasy and perspective-taking subscales. These results raise questions regarding opportunities for engineering students to develop their empathic abilities. It is important that engineering students acquire both theoretical and practical knowledge and skills regarding empathy.

Visual acuity in adults with Asperger's syndrome: no evidence for "eagle-eyed" vision.

BACKGROUND Autism spectrum conditions (ASC) are defined by criteria comprising impairments in social interaction and communication. Altered visual perception is one possible and often discussed cause of difficulties in social interaction and social communication. Recently, Ashwin et al. suggested that enhanced ability in local visual processing in ASC was due to superior visual acuity, but that study has been the subject of methodological criticism, placing the findings in doubt. METHODS The present study investigated visual acuity thresholds in 24 adults with Aspergers syndrome and compared their results with 25 control subjects with the 2 Meter 2000 Series Revised ETDRS Chart. RESULTS The distribution of visual acuities within the two groups was highly similar, and none of the participants had superior visual acuity. CONCLUSIONS Superior visual acuity in individuals with Aspergers syndrome could not be established, suggesting that differences in visual perception in ASC are not explained by this factor. A continued search for explanations of superior ability in local visual processing in persons with ASC is therefore warranted.

Hearing impairment, cognition and speech understanding: exploratory factor analyses of a comprehensive test battery for a group of hearing aid users, the n200 study

Abstract Objective: The aims of the current n200 study were to assess the structural relations between three classes of test variables (i.e. HEARING, COGNITION and aided speech-in-noise OUTCOMES) and to describe the theoretical implications of these relations for the Ease of Language Understanding (ELU) model. Study sample: Participants were 200 hard-of-hearing hearing-aid users, with a mean age of 60.8 years. Forty-three percent were females and the mean hearing threshold in the better ear was 37.4 dB HL. Design: LEVEL1 factor analyses extracted one factor per test and/or cognitive function based on a priori conceptualizations. The more abstract LEVEL 2 factor analyses were performed separately for the three classes of test variables. Results: The HEARING test variables resulted in two LEVEL 2 factors, which we labelled SENSITIVITY and TEMPORAL FINE STRUCTURE; the COGNITIVE variables in one COGNITION factor only, and OUTCOMES in two factors, NO CONTEXT and CONTEXT. COGNITION predicted the NO CONTEXT factor to a stronger extent than the CONTEXT outcome factor. TEMPORAL FINE STRUCTURE and SENSITIVITY were associated with COGNITION and all three contributed significantly and independently to especially the NO CONTEXT outcome scores (R2 = 0.40). Conclusions: All LEVEL 2 factors are important theoretically as well as for clinical assessment.

Justify your alpha

In response to recommendations to redefine statistical significance to P ≤ 0.005, we propose that researchers should transparently report and justify all choices they make when designing a study, including the alpha level.

Prospective Memory, Working Memory, Retrospective Memory and Self-Rated Memory Performance in Persons with Intellectual Disability

The purpose of the present study was to examine the relationship between prospective memory, working memory, retrospective memory and self-rated memory capacity in adults with and without intellect ...

Using developmental trajectories to examine verbal and visuospatial short-term memory development in children and adolescents with Williams and Down syndromes.

Williams (WS) and Down (DS) syndromes have been associated with specifically compromised short-term memory (STM) subsystems. Individuals with WS have shown impairments in visuospatial STM, while individuals with DS have often shown problems with the recall of verbal material. However, studies have not usually compared the development of STM skills in these domains, in these populations. The present study employed a cross-sectional developmental trajectories approach, plotting verbal and visuospatial STM performance against more general cognitive and chronological development, to investigate how the domain-specific skills of individuals with WS and DS may change as development progresses, as well as whether the difference between STM skill domains increases, in either group, as development progresses. Typically developing children, of broadly similar cognitive ability to the clinical groups, were also included. Planned between- and within-group comparisons were carried out. Individuals with WS and DS both showed the domain-specific STM weaknesses in overall performance that were expected based on the respective cognitive profiles. However, skills in both groups developed, according to general cognitive development, at similar rates to those of the TD group. In addition, no significant developmental divergence between STM domains was observed in either clinical group according to mental age or chronological age, although the general pattern of findings indicated that the influence of the latter variable across STM domains, particularly in WS, might merit further investigation.

A probabilistic fracture mechanics method and strength analysis of glulam beams with holes

A probabilistic fracture mechanics method is presented and applied to glulam beams with holes. The method is based on a combination of Weibull weakest link theory and a mean stress method which is a generalization of linear elastic fracture mechanics. Combining these two methods means that the global strength will be governed by both fracture energy and material strength and also that the stochastic nature of the material properties are taken into account. The probabilistic fracture mechanics method is evaluated by comparison to experimental test results. The method shows good ability to predict strength, with the exception of very small beams where the capacity is overestimated. The comparison to experimental tests deals also with other methods for strength analysis including code design methods.ZusammenfassungEin probabilistisches Bruchmechanikverfahren wird vorgestellt und auf Brettschichtholzträgern mit Durchbrüchen angewandt. Grundlage dieser Methode ist eine Kombination der Weibull Theorie des schwächsten Gliedes und der Methode der mittleren Spannung, einer Verallgemeinerung der linear-elastischen Bruchmechanik. Die Kombination dieser beiden Methoden bedeutet, dass die globale Festigkeit sowohl von der Bruchenergie als auch der Materialfestigkeit bestimmt wird und dass die stochastische Natur der Materialeigenschaften berücksichtigt wird. Das probabilistische Bruchmechanikverfahren wird durch Vergleich mit Versuchsergebnissen überprüft. Das Verfahren erweist sich als gut geeignet zur Vorhersage der Festigkeit mit Ausnahme von sehr kleinen Trägern, deren Tragfähigkeit überschätzt wird. Mit den Versuchsergebnissen werden auch andere Methoden der Festigkeitsanalyse einschließlich normierter Bemessungsverfahren verglichen.