Exploration in free word association networks: models and experiment

Free association is a task that requires a subject to express the first word to come to their mind when presented with a certain cue. It is a task which can be used to expose the basic mechanisms by which humans connect memories. In this work, we have made use of a publicly available database of free associations to model the exploration of the averaged network of associations using a statistical and the adaptive control of thought–rational (ACT-R) model. We performed, in addition, an online experiment asking participants to navigate the averaged network using their individual preferences for word associations. We have investigated the statistics of word repetitions in this guided association task. We find that the considered models mimic some of the statistical properties, viz the probability of word repetitions, the distance between repetitions and the distribution of association chain lengths, of the experiment, with the ACT-R model showing a particularly good fit to the experimental data for the more intricate properties as, for instance, the ratio of repetitions per length of association chains.     

Assessment of perception of morphed facial expressions using the Emotion Recognition Task: Normative data from healthy participants aged 8–75

The ability to recognize and label emotional facial expressions is an important aspect of social cognition. However, existing paradigms to examine this ability present only static facial expressions, suffer from ceiling effects or have limited or no norms. A computerized test, the Emotion Recognition Task (ERT), was developed to overcome these difficulties. In this study, we examined the effects of age, sex, and intellectual ability on emotion perception using the ERT. In this test, emotional facial expressions are presented as morphs gradually expressing one of the six basic emotions from neutral to four levels of intensity (40%, 60%, 80%, and 100%). The task was administered in 373 healthy participants aged 8–75. In children aged 8–17, only small developmental effects were found for the emotions anger and happiness, in contrast to adults who showed age‐related decline on anger, fear, happiness, and sadness. Sex differences were present predominantly in the adult participants. IQ only minimally affected the perception of disgust in the children, while years of education were correlated with all emotions but surprise and disgust in the adult participants. A regression‐based approach was adopted to present age‐ and education‐ or IQ‐adjusted normative data for use in clinical practice. Previous studies using the ERT have demonstrated selective impairments on specific emotions in a variety of psychiatric, neurologic, or neurodegenerative patient groups, making the ERT a valuable addition to existing paradigms for the assessment of emotion perception.     

Older Workers with Disabilities: Job Satisfaction Differences in the Public and Private Sectors in Europe

This study analyzes the differences in job satisfaction of older European people (aged 50-64), with or without disabilities, who are employed in either the public or the private sector. Using the data taken from the Survey of Health, Ageing and Retirement in Europe (SHARE) for the years 2004, 2007 and 2011, job satisfaction equations are estimated for workers from both the public and private sectors, with panel data techniques that include variables related to the worker's degree of disability (nondisabled, non-limited disabled, and limited disabled), among others. The results show that the disabled workers who are limited in their everyday activities are less satisfied in both the public and private sectors than those who are non-disabled and non-limited. In addition, the levels of job satisfaction for non-limited disabled people are higher than their non-disabled counterparts but only in the public sector. From a point of view of public policies, it is necessary to design and undertake measures and actions that would contribute to improving the levels of job satisfaction of older workers with disabilities, especially among those who are limited in their everyday activities.     

Cities and Immigration: A Reply

In my book, Cities and Immigration, I suggest shifting responsibilities for the integration of immigrants from the state to the city level. The articles in this issue challenge some of my suggestions. I discuss these challenges with regard to three questions: should a city enjoy greater autonomy to decide who, and how many, immigrants should settle within its borders? Should immigrants enjoy local voting rights even before naturalization? And is there a morally preferable model for integrating immigrants into the city?     

The update of semantic memories in amnestic mild cognitive impairment

It is still controversial to what extent neocortical consolidated memories are susceptible of change by processes of reconsolidation and transformation throughout experience, and whether the medial temporal lobes are necessary for this update of semantic consolidated memories, as they are for episodic remembering. We hypothesize that patients with amnestic mild cognitive impairment (aMCI) who have deficits in episodic memory may also have difficulties in updating information on added new features of objects. Sixteen participants with aMCI and 20 healthy control participants performed a semantic word-to-picture task, in which they were asked to identify as belonging to a given semantic category NEW objects, that have incorporated novel features, as well as OLD items, semantically and visually SIMILAR items and UNRELATED items. Patients with aMCI made a greater percentage of errors than healthy controls. Participants globally made greater percentages of errors in difficult types of items, namely NEW and SIMILAR, as compared to easier ones, OLD and UNRELATED. Importantly, an item by diagnostic group interaction effect was observed, and post hoc analysis showed that patients with aMCI made a higher percentage of errors than controls in NEW items only. In conclusion, patients with aMCI had a particular difficulty in identifying the NEW items of the word-to-picture task as compared to the control participants, supporting the concept of a flexible and dynamic conceptual knowledge system, involving the update of semantic memories and the integration of new attributes in a constant transformation process, which is impaired in these patients.     

An empirical Q-matrix validation method for the sequential generalized DINA model

As a core component of most cognitive diagnosis models, the Q-matrix, or item and attribute association matrix, is typically developed by domain experts, and tends to be subjective. It is critical to validate the Q-matrix empirically because a misspecified Q-matrix could result in erroneous attribute estimation. Most existing Q-matrix validation procedures are developed for dichotomous responses. However, in this paper, we propose a method to empirically detect and correct the misspecifications in the Q-matrix for graded response data based on the sequential generalized deterministic inputs, noisy ‘and’ gate (G-DINA) model. The proposed Q-matrix validation procedure is implemented in a stepwise manner based on the Wald test and an effect size measure. The feasibility of the proposed method is examined using simulation studies. Also, a set of data from the Trends in International Mathematics and Science Study (TIMSS) 2011 mathematics assessment is analysed for illustration.     

Early pathways to bullying: A prospective longitudinal study examining the influences of theory of mind and social preference on bullying behaviour during the first 3 years of school

Research has focused on the role of theory of mind (ToM) for positive social behaviour, while the association between ToM and negative social behaviours is less well understood. This longitudinal study compares two mediation models examining the role of ToM and peer-rated social preference at ages 5 and 6 for bullying at age 7. Participants were 114 children (58 boys, M_age = 67 months) at entry to primary school (T1). At Time 2 (T2), 106 children and, at Time 3 (T3), 96 children remained. Teacher-rated externalizing problems and children’s language ability were controlled at T1. Poor ToM was found to indirectly predict later bullying via poor social preference, while for boys only, greater earlier ToM directly predicted greater bullying 2 years later. These results suggest that there are different pathways to bullying via ToM and social preference , which has implications for interventions to prevent the development of bullying behaviour.