TMS in cognitive plasticity and the potential for rehabilitation

Cognitive neuroscientists use transcranial magnetic stimulation (TMS) in several ways, from aiming to increase understanding of brain-behavior relationships to transiently improving performance, both in normals and in patients with neurological and neuropsychological deficits. Different types of TMS (single-pulse, paired-pulse, repetitive) are able to interfere with higher brain functions that require the cooperation of different brain areas and complex neuronal networks. Currently, behavioral TMS effects on the brain are usually short-lived and their underlying mechanisms not yet wholly understood. However, the aim of using TMS to develop rehabilitative strategies for motor, perceptive and cognitive functions represents an intriguing challenge.     

Convergence of the Integration Dynamics of the Construction-Integration Model

The connectionist network corresponding to the nonlinear integration dynamical system associated with Kintsch's construction-integration (CI) model is analysed with linear algebra tools. This addresses some theoretical questions raised and left unanswered by Rodenhausen (1992, Psychological Review 99, 547-549). A mathematical characterization for equilibrium points, which allows an a priori enumeration of all possible asymptotic states for the integration dynamical system, given a connectivity matrix, is given. The dynamics of convergence of the integration dynamical system is characterized in some detail as well. This provides a tool for understanding CI simulations and helps in particular to let us know to what extent the outcome will depend on the initial conditions. The criteria also provide a new mathematical analysis which allows for the explicit calculation of asymptotic states of the integration process without requiring computer simulation experiments. The new mathematical analysis should facilitate comparisons of the model's predictions with behavioural data. Copyright 2001 Academic Press.     

Hypothesis testing in a rule discovery problem: when a focused procedure is effective.

We investigated individuals' ability to use negative evidence in hypothesis testing. We compared performance in two versions of Wason's (1960) rule discovery problem. In the original version, a triple of numbers--(2, 4, 6)--was presented as an example of a rule that the experimenter had in mind (i.e., "increasing numbers"). Participants had to discover the rule by proposing new triples. In the other version, the same triple was presented as a counter-example to the experimenter's rule (i.e., "decreasing numbers"). We predicted that, in both conditions, participants would form hypotheses based on the features of the triple, and test only instances of the hypothesized rule. However, in the counter-example condition, such focused testing would invariably produce negative evidence. As a consequence, participants would be forced to revise their hypotheses. The reported results corroborated our predictions: Participants solved the counter-example version significantly better than the original problem.     

Age Neutrality of Categorically and Dimensionally Measured DSM–5 Section II Personality Disorder Symptoms

Studies on the face validity of DSM–5 Section II categorical personality disorder (PD) symptoms indicate a bias against older adults. To extend these results, this article explores whether categorically and dimensionally scored PD symptoms of DSM–5 Section II, as measured in the Assessment of DSM–IV Personality Disorders (ADP–IV; Schotte & de Doncker, 1994), corroborate potential age bias across younger (aged 18–34), middle-aged (35–59 years), and older adults (aged 60–75). Differential item functioning (DIF) analyses, following a classical test theory approach, showed that 2 of the 79 symptoms were measured differently across 3 age groups when categorically assessed, and 4 when dimensionally measured. Nevertheless, subsequent differential test functioning analyses supported a low aggregated impact of DIF on the dimensional scales, justifying mean-level comparisons across age groups. Generalizability of the results is discussed in light of methodological issues concerning the research of age neutrality of PD symptoms, including the employed measurement instrument, PD symptom measurement approach, and sample and age range used to describe older adults.     

Adding a Conditional to Kripke’s Theory of Truth

Kripke’s theory of truth (Kripke, The Journal of Philosophy72(19), 690–716; 1975) has been very successful but shows well-known expressive difficulties; recently, Field has proposed to overcome them by adding a new conditional connective to it. In Field’s theories, desirable conditional and truth-theoretic principles are validated that Kripke’s theory does not yield. Some authors, however, are dissatisfied with certain aspects of Field’s theories, in particular the high complexity. I analyze Field’s models and pin down some reasons for discontent with them, focusing on the meaning of the new conditional and on the status of the principles so successfully recovered. Subsequently, I develop a semantics that improves on Kripke’s theory following Field’s program of adding a conditional to it, using some inductive constructions that include Kripke’s one and feature a strong evaluation for conditionals. The new theory overcomes several problems of Kripke’s one and, although weaker than Field’s proposals, it avoids the difficulties that affect them; at the same time, the new theory turns out to be quite simple. Moreover, the new construction can be used to model various conceptions of what a conditional connective is, in ways that are precluded to both Kripke’s and Field’s theories.     

Attentional control in the attentional blink is modulated by odor

Increasing evidence suggests that `aromas have distinctive effects on the allocation of attention in space: Arousing olfactory fragrances (e.g., peppermint) are supposed to induce a more focused state, and calming olfactory fragrances (e.g., lavender) a broader attentional state. Here, we investigate whether odors have similar effects on the allocation of attention in time. Participants performed the attentional blink (AB) task, known to produce a deficit in reporting the second of two target stimuli presented in close succession in a rapid sequence of distractors, while being exposed to either a peppermint or a lavender aroma. In two experiments using a between-subjects and a within-subjects design, respectively, we show that the two odors have specific effects on attentional control: As compared with the calming lavender aroma, the arousing peppermint condition yielded a larger AB. Our results demonstrate that attentional control is systematically modulated by factors that induce a more or a less distributed state of mind.     

Factorial Validity of the Personality Adjective Checklist in a Dutch-Speaking Sample

We examined the factorial structure of the Dutch version of the Personality Adjective Checklist (PACL–D) in a Belgian sample of 3,012 community-dwelling adults. Exploratory factor analyses revealed a 5-factor structure (Neurotic, Aggressive/Dominant, Introverted vs. Extraverted, Conscientious, and Cooperative), that showed considerable overlap with 3 of the Big Five factors (i.e., Neuroticism, Extraversion, and Conscientiousness). Moreover, the 5-factor structure closely resembled the structure found in the original American PACL and was equivalent across gender and age.     

Brain functional connectivity correlates of coping styles

Coping abilities represent the individual set of mental and behavioral strategies adopted when facing stress or traumatic experiences. Coping styles related to avoidance have been linked to a disposition to develop psychiatric disorders such as PTSD, anxiety, and major depression, whereas problem-oriented coping skills have been positively correlated with well-being and high quality of life. Even though coping styles constitute an important determinant of resilience and can impact many aspects of everyday living, no study has investigated their brain functional connectivity underpinnings in humans. Here we analyzed both psychometric scores of coping and resting-state fMRI data from 102 healthy adult participants. Controlling for personality and problem-solving abilities, we identified significant links between the propensity to adopt different coping styles and the functional connectivity profiles of regions belonging to the default mode (DMN) and anterior salience (AS) networks—namely, the anterior cingulate cortex, left frontopolar cortex, and left angular gyrus. Also, a reduced negative correlation between AS and DMN nodes explained variability in one specific coping style, related to avoiding problems while focusing on the emotional component of the stressor at hand, instead of relying on cognitive resources. These results might be integrated with current neurophysiological models of resilience and individual responses to stress, in order to understand the propensity to develop clinical conditions (e.g., PTSD) and predict the outcomes of psychotherapeutic interventions.     

Association Between Gait and Dual Task With Cognitive Domains in Older People With Cognitive Impairment

The authors investigated whether impaired gait and dual-task performances are associated with specific cognitive domains among older people with preserved cognition (PC), mild cognitive impairment (MCI), and mild Alzheimer's disease (AD). The sample comprised 40 older adults with PC, 40 with MCI, and 38 with mild AD. The assessment consisted of gait (measured by 10-m walk test and Timed Up and Go Test [TUGT]), dual task (measured by TUGT associated with a cognitive-motor task of calling a phone number), and cognition (domains of the Addenbrooke Cognitive Examination–Revised and Frontal Assessment Battery [FAB]). For data analysis, the Pearson product-moment correlation and the backward stepwise linear regression were conducted. Language, fluency, and visuospatial domains predicted the 10-m walk test measure specifically in PC, MCI, and AD groups. Only the visuospatial domain was independently associated with the TUGT measure in the MCI and AD groups. FAB score, language domain, and FAB score and fluency domain were the strongest predictors for the isolated cognitive-motor task measure in the PC, MCI, and AD groups, respectively. The visuospatial domain was independently associated with the dual-task test measure in all 3 groups. The study findings demonstrate the influence of specific cognitive domains in daily mobility tasks in people with different cognitive profiles.